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  • evolution  (202)
  • RFLP  (201)
  • Springer  (403)
  • 1990-1994  (403)
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 57 (1990), S. 143-150 
    ISSN: 1570-7458
    Keywords: Bruchidae ; Callosobruchus maculatus ; competition ; development ; evolution ; fecundity ; growth rates ; host preferences ; life tables ; mortality ; natural selection ; net reproductive rate ; oviposition traits
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Le taux partiel de reproduction nette (R inf0 sup* ) dépend de l'espèce de la plante sur laquelle les œufs sont pondus et du nombre de larves entrant dans la graine. La survie larvaire est réduite par 1/(le nombre de larves par graine) parce qu'une seule larve se développe dans une graine. La fécondité n'est pas modifiée par la compétition subie par les larves, la mortalité larvaire a l'effet le plus important sur R inf0 sup* . Les femelles éliminent ou réduisent la compétition larvaire en dispersant leurs œufs uniformément et font si peu d'erreurs avec une hyperdispersion que l'évolution d'un comportement plus précis n'accroîtrait R inf0 sup* que de 4% au maximum. Des femelles retournant à une distribution des œufs au hasard provoqueraient une réduction de R inf0 sup* de 25% au moins. Les légumineuses généralement cultivées dans l'Inde du Sud sont des hôtes acceptables quand elles sont présentées seules. Le choix des femelles entre 2 hôtes élève R inf0 sup* de 30% ou plus par rapport à une distribution au hasard. Les préférences les plus nettes concernent des combinaisons présentant la plus grande différence de R inf0 sup* . Les femelles qui hyperdispersent leurs œufs, choisissent leurs hôtes et évitent les pertes par compétition en empêchant que les œufs ne donnent plus de descendants que ne le ferait une ponte au hasard. Les particularités de la ponte sont variables et héritables. Les lignées se sélectionnent bien, en fonction de la dispersion de leurs œufs sur les graines, de la discrimination des plantes hôtes, et de la modulation de leur taux de ponte. La sélection naturelle maintient ces particularités du comportement d'une façon sédentaire.
    Notes: Abstract The deposition of eggs by this strain of Callosobruchus maculatus (Fab.) (Bruchidae: Coleoptera) departs from randomness in three ways; eggs are uniformly dispersed, oviposition rates drop when beans begin to carry 2 or more eggs, and there are sharp host preferences. Using random egg placement for the unspecialized condition, these traits are evaluated for their effect on a female's contributions of offspring to the next generation (R0, the net reproductive rate). The major increases in R0 result from females dispersing eggs so uniformly that larval competition is either reduced or eliminated. Females reduce their oviposition rate when the larva from an egg added to a bean is almost certain to die in competitive encounters. Host preferences and larval survival in a host are positively associated with the abundance of the host in South India. The three oviposition traits act together to give and R0 that is 25–50% than that of eggs placed at random. These traits are known to be variable and heritable, hence, the conditions necessary for natural selection are statisfied.
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  • 2
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    Entomologia experimentalis et applicata 60 (1991), S. 173-182 
    ISSN: 1570-7458
    Keywords: Genetics ; evolution ; host adaptation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract When populations are exposed to different environments, evolutionary processes can lead either to genetically differentiated strains or to the appearance of increased generalism at the individual level. For evolution to occur, genetic variability in performance in different environments is required. Here, intraspecific genetic variation across environments was estimated in the flour beetle Tribolium castaneum (Herbst) by comparing the responses of two strains of T. castaneum to different flour types. Replicated groups from each strain were allowed to develop on either the standard whole wheat medium or on one of four novel flours (wheat, rice, corn and oat). In several of the novel flours, clear differences in mean development time or population size of one or both strains were seen relative to performance in the standard medium. Moreover, the strains differed significantly in their phenotypic responses to the flours. One strain did particularly poorly on oat flour. Reduced oviposition, reduced larval survivorship and increased larval cannibalism were examined as possible causes of the low productivity on oat flour. These three factors accounted for about 70% of the reduction in population size when this strain oviposited and developed in oat flour. The difference between these two outbred strains in response to these five flours suggests that genetic variation in resource use is present within T. castaneum and may also be present within strains and natural populations in grain storage facilities. Such variation would permit an evolutionary response to selection in multiple environments (flours). This process has agricultural implications when several types of grain are stored in a single location because it could eventually lead to the evolution of highly generalized populations of T. castaneum, an important pest of stored products.
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  • 3
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    Journal of insect behavior 6 (1993), S. 715-735 
    ISSN: 1572-8889
    Keywords: Aphrodisiac ; cockroach ; evolution ; mating behavior ; sex pheromone ; sternal glands ; tergal glands
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two chemical signals are essential in all cockroach sexual behavioral sequences: the sex pheromone released by one partner, generally the female (for long distance attraction), and an aphrodisiac sex pheromone produced exclusively by male tergal glands (for female mounting and tergal contact or “feeding” behavior). Unlike the other cockroach groups, the males of the Oxyhaloinae species produce both chemical signals: the pheromone and the aphrodisiac. The occurrence of three patterns of mating behavior (A, B, and C), the production of male sex pheromones, and the existence in the male of developed sternal and tergal glands in seven related Oxyhaloinae species, make these cockroaches a useful model for studying the evolution of mating behavior patterns. The various types of mating behavior were not classified in the previous studies by Roth and Barth. In this report, they have been named type A (female in upper position), B (male in upper position), and C (male and female end to end). In type A mating, the male tergal glands, which are licked by the females, are well developed, whereas in types B and C, there is no licking of the male's tergal secretion by the females and the tergal glands are much less developed; the aphrodisiacs secreted by the tergal glands may no longer act in this case through contact chemoreception, but through an olfactory process involving volatile components. One common sex pheromone component seems to be acetoin. I suggest that the mating behavior tends from A toward B and C during the evolutionary process with a concomitant regression of the tergal glands and changes in the aphrodisiac emission levels. The mating behavioral sequences of cockroaches (Dictyoptera) and crickets (Orthoptera) show a striking degree of similarity and are probably examples of convergent evolution.
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  • 4
    ISSN: 1572-8889
    Keywords: Belostomatidae ; giant water bugs ; paternal care ; eggs ; reproduction ; behavior ; brooding ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Males of the giant water bug Lethocerus medius(Guerin) typify their monobasic subfamily, the Lethocerinae, in that they do not brood eggs attached to their backs as do males of all members of the subfamily Belostomatinae. Exclusive male parental investment as expressed in the Belostomatinae is extremely rare behavior among animals, and evolution of the trait is obscure. Lethocerus mediusmales apparently remain with their mates through oviposition and are consistently found in attendance of eggs after the female has departed. This behavior may enhance paternity assurance at no cost in opportunity for polygyny. Two double clutches of eggs were found, from which we infer the potential for polygynous matings and shared parental investment. Male L. mediusbrood attended egg clutches above the surface of the water, where they may moisten them, shade them, and defend them against predation. Egg attendance/brooding by L. mediusand other Lethocerusspecies may represent a plesiomorphic state from which paternal back- brooding evolved in the Belostomatinae.
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  • 5
    ISSN: 1420-9071
    Keywords: Mitochondrial DNA ; RFLP ; Leptinotarsa decemlineata ; Colorado potato beetle ; population genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This study demonstrates variability in restriction enzyme cleavage sites of mitochondrial DNA (mtDNA) among four popalations of Colorado potato beetle (CPB). A suite of three enzymes (EcoRI,HpaI,PstI) was sufficient to discriminate among the populations tested. Individuals heteroplasmic for restriction enzyme patterns were found in some populations. Variability in CPB mtDNA should prove useful in efforts to trace the origin and dispersal of the species in North America.
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  • 6
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    Cellular and molecular life sciences 50 (1994), S. 521-523 
    ISSN: 1420-9071
    Keywords: Ancient DNA ; evolution ; conservation ; biology ; anthropology ; plant biology ; PCR (polymerase chain reaction)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
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  • 7
    ISSN: 1420-9071
    Keywords: Insect ; behaviour ; high-speed cinematography ; jumping ; electrophysiology ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The Indian antHarpegnathos saltator may be unique among insects in using its jumping capacity not only as an escape mechanism but also as a normal means of locomotion, and for catching its prey in flight. High-speed cinematography used to analyse the various phases of the jump suggests thatHarpegnathos employs a novel jumping mechanism to mediate these behaviours: namely the synchronous activation of its middle and hindlegs. Electrophysiological recordings from muscles or nerves in pairs of middle and hindlegs show remarkably synchronous activity during fictive jumping, supporting the synchronous activation hypothesis.Harpegnathos is not the only ant to jump, and a cladistic analysis suggests that jumping behaviour evolved independently three times during ant evolutionary history.
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  • 8
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    Cellular and molecular life sciences 46 (1990), S. 1106-1117 
    ISSN: 1420-9071
    Keywords: Genetic code ; eucaryotic cell ; evolution ; code ambiguity ; code universality ; convergence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This article is a review of the rules used by eucaryotic cells to translate a nuclear messenger RNA into a polypeptide chain. The recent observation that these rules are not identical in two species of a same phylum indicates that they have changed during the course of evolution. Possible scenarios for such changes are presented.
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  • 9
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    Cellular and molecular life sciences 49 (1993), S. 1027-1036 
    ISSN: 1420-9071
    Keywords: Archaea (archaebacteria) ; extreme halophiles ; archaeol phospholipids ; archaeol glycolipids ; membrane function ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Archaebacteria (archaea) are comprised of three groups of prokaryotes: extreme halophiles, methanogens and thermoacidophiles (extreme thermophiles). Their membrane phospholipids and glycolipids are derived entirely from a saturated, isopranoid glycerol diether,sn-2,3-diphytanylglycerol (‘archaeol’) and/or its dimer, dibiphytanyldiglyceroltetraether (‘caldarchaeol’). In extreme halophiles, the major phospholipid is the archaeol analogue of phosphatidylglycerolmethylphosphate (PGP-Me); the glycolipids are sulfated and/or unsulfated glycosyl archaeols with diverse carbohydrate structure characteristic of taxons on the generic level. Biosynthesis of these archaeol-derived polar lipids occurs in a multienzyme, membrane-bound system that is absolutely dependent on high salt concentration (4 M). The highly complex biosynthetic pathways involve intermediates containing glycerol ether-linked C20-isoprenyl groups which are reduced to phytanyl groups to give the final saturated polar lipids. In methanogens, polar lipids are derived both from archaeol and caldarchaeol, and thermoacidophiles contain essentially only caldarchaeol-derived polar lipids. The function of these membrane polar lipids in maintaining the stability, fluidity and ionic properties of the cell membrane of extreme halophiles, as well as the evolutionary implications of the archaeol and caldarchaeol-derived structures will be discussed.
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  • 10
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    Cellular and molecular life sciences 48 (1992), S. 729-731 
    ISSN: 1420-9071
    Keywords: Urea cycle ; leech ; botryoidal tissue ; hirudineans ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Ornithine carbamoyltransferase (OCT) and arginase, but not arginine synthetase (AS), were detected in the body wall and gut tissues of the leech. The activities of these enzymes were not altered by starvation. The high activity of arginase in body wall is probably due to the association of the latter with botryoidal tissue. Hirudineans, which evolved from oligochaete ancestors, appear to have lost the citrulline-arginine segment of the urea cycle due to their ammonotelic mode of nitrogen excretion.
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  • 11
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    Cellular and molecular life sciences 50 (1994), S. 987-1001 
    ISSN: 1420-9071
    Keywords: Hsp70 ; evolution ; gene duplication ; gene homology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The family of genes encoding heat shock proteins of about 70 kDa (hsp70) in vertebrates is reviewed under genetic aspects. After a detailed description of the various hsp70 genes more general characteristics of the organization and evolution of the multigene family are discussed.
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  • 12
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    Cellular and molecular life sciences 49 (1993), S. 317-319 
    ISSN: 1420-9071
    Keywords: Chitin ; cuticle ; evolution ; vertebrates ; bony fish ; Blenniidae ; Paralipophrys trigoides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Lectin binding, endo-chitinase binding and enzymatic degradation studies show that the epidermal cuticle of the bony fishParalipophrys trigloides (Blenniidae) is chitinous. This is the first evidence that a vertebrate species possesses a chitinous tissue. Recently aXenopus gene has been identified which has significant sequence similarity to the catalytic domain of yeast chitin synthase III, a chitin producing enzyme1,2. Taken together these two findings imply that chitin synthesis capability may be a basic vertebrate feature.
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  • 13
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    Cellular and molecular life sciences 50 (1994), S. 429-437 
    ISSN: 1420-9071
    Keywords: Genetics ; ecology ; DNA-transfer ; conjugation ; transformation ; transduction ; transposons ; dormant cells ; epilithon ; microbial colonisation ; symbiosis ; virus resistance ; biosafety ; release of genes ; insults to humanity ; evolution ; biodiversity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Genetic ecology is the extension of our modern knowledge in molecular genetics to studies of viability, gene expression and gene movements in natural environments like soils, aquifers and digestive tracts. In such milieux, the horizontal transfer of plasmid-borne genes between phylogenetically distant species has already been found to be much more frequent than had been expected from laboratory experience. For the study of exchanges involving chromosomally-located genes, more has to be learned about the behaviour of transposons in such environments. The results expected from studies in genetic ecology are relevant for considerations of evolution, biodiversity and biosafety. The role of this new field of research in restoring popular confidence in science and in its biotechnological applications is stressed.
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  • 14
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    Journal for general philosophy of science 21 (1990), S. 231-257 
    ISSN: 1572-8587
    Keywords: basic rules ; change ; discipline-neutral ; evolution ; analogy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Nature of Science, Research, Systems of Higher Education, Museum Science
    Notes: Summary A small step is made in the direction of defining some general basic rules which can serve as a framework for research in several fields of the social sciences. The method of working with analogies asks for a more accurate approach. Starting from the concept of evolution in the form of a basic rule another basic rule is formulated. This rule shows what are the most important factors in long term developments and what types of development one can expect.
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  • 15
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    Journal for general philosophy of science 22 (1991), S. 133-141 
    ISSN: 1572-8587
    Keywords: evolution ; teleology ; chance ; purpose ; anthropomorphism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Nature of Science, Research, Systems of Higher Education, Museum Science
    Notes: Summary Revaluation of the problem of natural teleology seems an important precondition for elucidating our environmental crisis and for formulating an ‘ecological ethics’, because it calls for a recognition of an intrinsic value in nature and organisms. Therefore, it is necessary to show that the concept of natural teleology is not in contradiction with scientific theories, in particular not with the theory of evolution. In this paper I shall argue that there is a fundamental misunderstanding about the concepts of teleology and chance in modern thinking. This as a result of a radical transformation of the Aristotelian concept of teleology by Christian theologians during the Middle Ages. This confusion resulted in the rejection of teleology from evolution and in an exaggeration of the role of chance. However, not a solution for the problem of teleology is given here, but only an attempt to prove that neither the fossil-record, nor the role of chance in evolution can give adequate arguments for the negation of teleology in evolution. That is not to say that, therefore there exists teleology in evolution, but the problem of teleology in nature cannot, be solved by the scientific theory of evolution, but only be elucidated by philosophical analysis. At the end of the paper it is argued that teleology must be rather presupposed in evolution.
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  • 16
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    Journal for general philosophy of science 23 (1992), S. 85-103 
    ISSN: 1572-8587
    Keywords: life ; teleology ; evolution ; reality ; representation ; experience
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Nature of Science, Research, Systems of Higher Education, Museum Science
    Notes: Summary A comprehensive definition of the phenomenon called “life” led to the addition of many dimensions to the natural sciences, and especially the conscious mental dimension. Historical attention is paid not only to those employing the natural philosophical paradigms, but also to evolutionary theories and to the Kantian teleological philosophy. The belief that science can solve the riddle of life is a category of purposal thinking. A revised version of critical teleology is essential for comprehension of life.
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  • 17
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    Entomologia experimentalis et applicata 66 (1993), S. 3-12 
    ISSN: 1570-7458
    Keywords: evolution ; coevolution ; selection ; insect attack ; plant defense ; competition ; enemy free space ; chemoreception ; specialization ; plant recognition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Most hypotheses concerning the evolution of insect-plant relationships are based on the assumptions that, (1) phytophagous insects reduce plant fitness, and that (2) insect-plant relationships are the result of unconstrained selection. It can be shown, however, that there is little evidence to support these assumptions. As an alternative, it is proposed that the evolution of insect-plant relationships results primarily from autonomous evolutionary events; namely from heritable functional changes within the insects' nervous system that determine plant recognition and ultimately host plant specificity. These changes cannot be evoked by selective ecological agents. They originate from intrinsic changes (mutationssensu lato) within the insect genome. Ecological factors play a secondary role: by either supporting or preventing the establishment of the new genotype with the novel food preference.
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  • 18
    ISSN: 1570-7458
    Keywords: Cryptomyzus ; aphid ; hybridization ; host plant preference ; reproductive performance ; host-alternation ; speciation ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé C. galeopsidis Kaltenbach contient plusieurs formes qui ont différentes relations avec des plantes hôtes et des cycles distincts. Des croisements ont permis d'élucider la taxonomie de ces formes et d'étudier l'hérédité de préférences d'hôtes, des performances reproductives et de l'alternance d'hôtes. Une des formes apparaît comme une espèce distincte par suite de la valeur adaptative réduite des hybrides. Les autres formes avec alternance ou non des hôtes sont considérées comme conspécifiques et représentant deux stratégies vitales différentes. Les performances reproductives sont probablement polygéniques puisque les hybrides ont des performances intermédiaires. Les préférences d'hôtes des hybrides montrent certains degrés de dominance et semblent déterminées par quelques gènes seulement. L'alternance des hôtes est envisagée comme ayant une hérédité monofactorielle. Les conséquences sur la spéciation sont discutées.
    Notes: Abstract The aphid species Cryptomyzus galeopsidis (Kaltenbach) includes several distinct forms which have different host plant relationships and life cycles. Cross breeding was used to elucidate the taxonomic status of these forms and to investigate the inheritance of host preference, reproductive performance and host-alternation. One of the forms appeared to be a distinct species because of the reduced fitness of the hybrids. Other host-alternating and non host-alternating forms are considered conspecific and represent two life cycle strategies. Reproductive performance is probably controlled polygenically, since hybrids show an intermediate performance. Host preference in hybrids showed some degree of dominance and seemed to be determined by only a few genes. Host-alternation is presumed to be inherited monofactorially. The implications for speciation are discussed.
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  • 19
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    Journal of paleolimnology 10 (1994), S. 43-52 
    ISSN: 1573-0417
    Keywords: Charophyta ; evolution ; gyrogonite morphology ; ecology-paleoecology ; Argentina ; South America
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Charophyta are common algae in limnic waters from many regions and are an interesting group from an evolutionary point-of-view, as they are believed to be related to the Chlorophyceae and land plants. Paleontological-botanical systematics are discussed, taking into consideration some new advances. Charophytes live in all types of inland waters and are sensitive to ecological change, and so they are very useful paleolimnological markers. Gaps concerning gyrogonite morphology in extant taxa and their responses to different environmental conditions must be described. This paper discusses data concerning ecological factors affecting the distribution of Argentinian Charophyta (principally distributed between 30°S and 40°S), gyrogonite morphology related to different ecological conditions, and the way that Charophyta can modify the environment.
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  • 20
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    Journal of paleolimnology 10 (1994), S. 53-58 
    ISSN: 1573-0417
    Keywords: Charophyta ; evolution ; gyrogonite morphology ; ecology-paleoecology ; Argentina ; South America
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract The Pleistocene charophytes from Arroyo Perucho Verna, Province of Entre Ríos, were analyzed.Chara contraria Br. ex Kütz.,C. contraria var.longilinea Cáceres,C. globularis Thuill. andTolypella intricata (Trent. ex Roth.) Leonh. var.apiculata (A. Br.) Wood were described and illustrated with scanning electron microscope. The assemblage indicates fresh alkaline to slightly saline waters, not very deep, in a lentic or sometimes lotic environment. Extant assemblages provide data for this paleoecological reconstruction.
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  • 21
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    Antonie van Leeuwenhoek 61 (1992), S. 1-33 
    ISSN: 1572-9699
    Keywords: Paracoccus denitrificans ; denitrification ; methylotrophy ; cytochromec ; cytochrome oxidase ; phylogeny ; evolution ; lateral gene transfer ; nitrogen fixation ; Thiosphaera pantotropha
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Denitrification and methylotrophy inParacoccus denitrificans are discussed. The properties of the enzymes of denitrification: the nitrate-nitrite antiporter, nitrate reductase, nitrite reductase, nitric oxide reductase and nitrous oxide reductase are described. The genes for none of these proteins have yet been cloned and sequenced fromP. denitrificans. A number of sequences are available for enzymes fromEscherichia coli, Pseudomonas stutzeri andPseudomonas aeruginosa. It is concluded that pathway specificc-type cytochromes are involved in denitrification. At least 40 genes are involved in denitrification. In methanol oxidation at least 20 genes are involved. In this case too pathway specificc-type cytochromes are involved. The sequence homology between the quinoproteins methanol dehydrogenase, alcoholdehydrogenase and glucose dehydrogenase is discussed. This superfamily of proteins is believed to be derived from a common ancestor. ThemoxFJGI operon determines the structural components of methanol dehydrogenase and the associatedc-type cytochrome. Upstream of this operon 3 regulatory proteins were found. The mox Y protein shows the general features of a sensor protein and the moxX protein those of a regulatory protein. Thus a two component regulatory system is involved in both denitrification and methylotrophy. The phylogeny of prokaryotes based on 16S rRNA sequence is discussed. It is remarkable that the 16S rRNA ofThiosphaera pantotropha is identical to that ofP. denitrificans. Still these bacteria show a number of differences.T. pantotropha is able to denitrify under aerobic circumstances and it shows heterotrophic nitrification. Nitrification and heterotrophic nitrification are found in species belonging to the β-and γ-subdivisions of purple non-sulfur bacteria. Thus the occurrence of heterotrophic nitrification inT. pantotropha which belongs to the α-subdivision of purple non-sulfur bacteria is a remarkable property. FurthermoreT. pantotropha contains two nitrate reductases of which the periplasmic one is supposed to be involved in aerobic denitrification. The nitrite reductase is of the Cu-type and not of the cytochromecd 1 type as inP. denitrificans. Also the cytochromeb of theQbc complex ofT. pantotropha is highly similar to its counterpart inP. denitrificans. It is hypothesized that the differences between these two organisms which both contain large megaplasmids is due to a combination of loss of genetic information and plasmid-coded properties. The distribution of a number of complex metabolic systems in eubacteria and in a number of species belonging to the α-group of purple non sulphur bacteria is reviewed. Two possibilities to explain this haphazard distribution are considered: 1. Lateral gene transfer between distantly related micro organisms occurs frequently. 2. The eubacterial ancestors must have possessed already these properties. The distribution of these properties is due to sporadic loss during evolutionary divergence. With respect to the occurrence and frequency of lateral gene transfer two opposing views exist. According to molecular biologists lateral gene transfer occurs frequently and is very easy. Bacteria are supposed to form one large gene pool. On the other hand population geneticists have provided evidence that strong systems operate that establish reproductive isolation between diverged species and even between closely related cell lines. Data on amino acid sequences of nitrogenase proteins, cytochromesc, cytochrome oxidases, β-subunits of ATP synthase and tryptophan biosynthetic enzymes of various micro organisms were reviewed. In all these cases phylogenetic trees could be constructed based on the amino acid sequence data. In all cases this phylogenetic tree was similar to the one based on 16S rRNA homology. Only in one case evidence for the occurrence of lateral gene transfer was obtained. Therefore it is concluded that lateral gene transfer played a minor role in the distribution of complex metabolic systems among prokaryotes. It must be stressed that this does not exclude the possibility that lateral gene transfer occurred frequently in the initial stage of bacterial evolution. It is hypothesized that the appearance of nitrogen fixation, denitrification and cytochrome oxidase formation were early events in the evolution of micro organisms. Both systems are supposed to have evolved only once. Subsequently the capacity to fix nitrogen or to denitrifymust have been lost many times, just as photosynthetic capacity is supposed to have been lost many times. During evolution many systems have been lost leading to a haphazard distribution of metabolic characters among bacteria. As an example it is suggested that organisms with a respiratory chain similar to that ofEscherichia coli arose by loss of the capacity to form the Qbc complex andc-type cytochromes. The remaining systems could be controlled much better however than in the ancestral organisms.
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  • 22
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    Biodegradation 5 (1994), S. 195-217 
    ISSN: 1572-9729
    Keywords: Aromatic catabolism ; by bacteria (Pseudomonas) ; evolution ; of catabolic pathways ; hydrocarbons ; catabolism of aromatic ; Pseudomonas ; evolution of catabolism in ; oxygenases ; evolution of
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The organisation and nucleotide sequences coding for the catabolism of benzene, toluene (and xylenes), naphthalene and biphenylvia catechol and the extradiol (meta) cleavage pathway inPseudomonas are reviewed and the various factors which may have played a part in their evolution are considered. The data suggests that the complete pathways have evolved in a modular way probably from at least three elements. The commonmeta pathway operons, downstream from the ferredoxin-like protein adjacent to the gene for catechol 2,3-dioxygenase, are highly homologous and clearly share a common ancestry. This common module may have become fused to a gene or genes the product(s) of which could convert a stable chemical (benzoate, salicylate, toluene, benzene, phenol) to catechol, thus forming the lower pathway operons found in modern strains. The upper pathway operons might then have been acquired as a third module at a later stage thus increasing the catabolic versatility of the host strains.
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  • 23
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    Development genes and evolution 204 (1994), S. 62-69 
    ISSN: 1432-041X
    Keywords: Cell determination ; direct development dorsoventral axis ; echinoids ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the direct-developing sea urchinHeliocidaris erythrogramma the first cleavage division bisects the dorsoventral axis of the developing embryo along a frontal plane. In the two-celled embryo one of the blastomeres, the ventral cell (V), gives rise to all pigmented mesenchyme, as well as to the vestibule of the echinus rudiment. Upon isolation, however, the dorsal blastomere (D) displays some regulation, and is able to form a small number of pigmented mesenchyme cells and even a vestibule. We have examined the spatial and temporal determination of cell fates along the dorsoventral axis during subsequent development. We demonstrate that the dorsoventral axis is resident within both cells of the two-celled embryo, but only the ventral pole of this axis has a rigidly fixed identity this early in development. The polarity of this axis remains the same in half-embryos developing from isolated ventral (V) blastomeres, but it can flip 180° in half-embryos developing from isolated dorsal (D) blastomeres. We find that cell fates are progressively determined along the dorsoventral axis up to the time of gastrulation. The ability of dorsal half-embryos to differentiate ventral cell fates diminishes as they are isolated at progressively later stages of development. These results suggest that the determination of cell fates along the dorsoventral axis inH. erythrogramma is regulated via inductive interactions organized by cells within the ventral half of the embryo.
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  • 24
    ISSN: 1420-9098
    Keywords: Leptothorax acervorum ; mtDNA ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary 27 nests ofLeptothorax acervorum were analysed for restriction fragment-length polymorphism (RFLP) in mitochondrial DNA (mtDNA), using four endonucleases. A substantial degree of variation was found between nests in the population (13 composite haplotypes). Intra-nest variation was detected in 15 % of the nests. The presence of occasional alien inseminated females indicates that polygyny in this species is caused by adoption of mated females. The occasional acceptance of alien females is difficult to explain, but interesting, since this behaviour could have given rise to inquilinism. Our results suggest that analysis of mtDNA RFLP is a method well suited for investigations of the population structure of ants.
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  • 25
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    Insectes sociaux 38 (1991), S. 263-272 
    ISSN: 1420-9098
    Keywords: Isoptera ; Kalotermitidae ; Neotermes papua ; termites ; caste differentiation ; division of labour ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The direct development ofNeotermes papua (Isoptera: Kalotermitidae) comprises four larval and three nymphal instars before the alate. The first five instars can be easily characterized. The second stage nymphs come morphologically close to the pseudergates, characterized by reduced wing buds. These nymphs can moult stationarily, i.e. with little morphological change, or to presoldiers, or proceed to the alate via the third nymphal stage. Pseudergates originate through a late and reversible deviation from the straight development to the alate. Presoldiers may derive from several stages, up to the last nymphal one; their production is subject to an inhibition by extant soldiers. This developmental schema is congruent with those described in other Kalotermitidae and the Termopsidae. By pinpointing the existence of a large pool of pluripotent individuals, in which the penultimate nymphal stage mingles with pseudergates, the present study also reveals a great similarity betweenNeotermes andProrhinotermes, and suggests that this developmental schema might be generally applicable to termites devoid of a permanent worker caste.
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  • 26
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    Insectes sociaux 40 (1993), S. 325-335 
    ISSN: 1420-9098
    Keywords: Formicidae ; social parasitism ; PCR ; 18 S ribosomal RNA ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The evolutionary relationship between socially parasitic ants and their hosts is still an unsolved problem. We have compared a 1.2 kb sequence of the 18 S ribosomal RNA genes of the parasitic antsDoronomyrmex kutteri, Harpagoxenus sublaevis andChalepoxenus muellerianus to the sequence of the host speciesLeptothorax acervorum andL. recedens (all subfamily Myrmicinae, tribe Leptothoracini) and to an out-group antCamponotus ligniperda (Formicinae). We found that parasitic species and the host species and alsoCamponotus ligniperda differ at less than 1% of the base positions of the 1.2 kb segment of the 18S rRNA gene. The sequences showed 80.3% identity to the 18 S ribosomal RNA genes of the beetleTenebrio molitor and only 66.5% to that of the dipteranDrosophila melanogaster.
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  • 27
    ISSN: 1420-9098
    Keywords: Isoptera ; Termitidae ; Nasutitermitinae ; caste differentiation ; phylogeny ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The developmental pattern of the neuter castes was studied in the mandibulate nasute generaCornitermes, Embiratermes andRhynchotermes. InCornitermes walkeri, all the workers and soldiers are male. There are two larval and a single worker instar. Workers can molt into presoldiers. InEmbiratermes chagresi andRhynchotermes perarmatus, both sexes are present among the neuters. A slight sexual dimorphism (males 〉 females) is discernible among both larval instars and among workers ofE. chagresi; female workers can molt into presoldiers. InR. perarmatus, the sexual dimorphism is conspicuous from the first larval instar on. Male larvae go through two instars, then give rise to workers, which do not molt. InR. perarmatus, there is no worker stage in females, but a third larval instar, preceding the presoldier. Hypotheses are proposed as to the evolution of these caste patterns, attempting to conciliate present knowledge of Nasutitermitinae phylogeny and known evolutionary trends affecting termite caste patterns, according to the species' ecology.
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  • 28
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    Insectes sociaux 39 (1992), S. 425-438 
    ISSN: 1420-9098
    Keywords: Formicidae ; Nothomyrmecia ; evolution ; sociogram ; ethogram ; recognition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Results of laboratory-based ethological studies on twoNothomyrmecia macrops colonies with individually marked workers are reported. Interactive behavioural acts constituted less than 1% of all those recorded, revealing a strong tendency by the ants not to engage in social contact. Very few workers performed queen-directed acts. They stayed near the queen, though seldom in direct contact. Division of labour was otherwise barely apparent, except that some individuals showed a propensity to guard the nest entrance. No exchange of food was observed between workers, workers and queen, or adults and larvae (apart from worker placement of prey items with larvae). A queen fed from aDrosophila carcass retrieved from the nest floor, without assistance from workers. Systematic scanned observations confirmed levels of inactivity higher than previously observed in ants (comprising almost 2/3 of recorded behavioural acts). The time budget for activities directed toward the immature stages was the same in both colonies, and fluctuated during the circadian period. Non-nestmate larvae added to worker groups were more frequently licked than nestmate larvae, but this might not involve the particular recognition of nestmateversus non-nestmate brood. These observations support the hypothesis thatNothomyrmecia is primitively eusocial, and of special significance in myrmecology.
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  • 29
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    Cellular and molecular life sciences 46 (1990), S. 1117-1126 
    ISSN: 1420-9071
    Keywords: Genetic code ; mitochondria ; evolution ; organelles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The universal genetic code is used without changes in chloroplasts and in mitochondria of green plants. Non-plant mitochondria use codes that include changes from the universal code. Chloroplasts use 31 anticodons in translating the code; a number smaller than that used by bacteria, because chloroplasts have eliminated 10 CNN anticodons that are found in bacteria. Green plant mitochondria (mt) obtain some tRNAs from the cytosol, and genes for some other tRNAs have been acquired from chloroplast DNA. The code in non-plant mt differs from the universal code in the following usages found in various organisms: UGA for Trp, AUA for Met, AGR for Ser and stop, AAA for Asn, CUN for Thr, and possibly UAA for Tyr. CGN codons are not used byTorulopsis yeast mt. Non-plant mt, e.g. in vertebrates, may use a minimum of 22 anticodons for complete translation of mRNA sequences. The following possible causes are regarded as contributing to changes in the non-plant mt: directional mutation pressure, genomic economization, changes in charging specificity of tRNAs, loss of release factor RF2, changes in RF1, changes in anticodons, loss of lysidine-forming enzyme system, and disappearance of codons from coding sequences.
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  • 30
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    Cellular and molecular life sciences 46 (1990), S. 251-254 
    ISSN: 1420-9071
    Keywords: Bronchial tree ; evolution ; fractal ; lung airway ; morphogenesis ; renormalization group theory
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    Topics: Biology , Medicine
    Notes: Summary The mammalian lung exhibits features of a fractal tree: heterogeneity, self-similarity and the absence of a characteristic scale. The finite nature of the lung ultimately limits the range over which self-similarity scaling characteristics are applicable. However, generalization based on the scaling features of fractals, provides unique insight into geometric organization of anatomic structures. Furthermore, the mathematical theory of renormalization groups provides a description of the harmonically-modulated inverse power-law scaling observed for bronchial tree dimensions observed in different species. Compared to several mammalian species (dog, rat, hamster), the human lung shows marked differences in the phase of the harmonic modulation for both length and diameter measurements. These inter-species scaling differences suggest that evolutionary factors modify certain universal features of morphogenesis.
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  • 31
    ISSN: 1420-9071
    Keywords: Biological clock ; cell division cycle ; diaminopimelate ; evolution ; FSu ; lysine ; muramate ; muramyl dipeptide ; peptidoglycan ; sleep muropeptide ; tumor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Degradation products of peptidoglycan, the universal bacterial cell wall constituent, were previously found in animal tissues and urine. Reassessment and quantitative analysis of available data lead to an original concept, i.e. that eukaryotic cells synthesize peptidoglycan. We present a model in which this endogenously synthesized peptidoglycan is essential for the processes of eukaryotic cell division and sleep induction in animals. Genes for peptidoglycan metabolism, like those for lysine biosynthesis in plants, are probably inherited from endosymbiotic bacteria, the ancestors of mitochondria and chloroplasts. Corollaries of this concept, i.e. roles for peptidoglycan metabolism in tumor formation and in the biological clock, are supported by abundant evidence. We propose that many interactions between bacteria and eukaryotes are conditioned by their common genetic heritage.
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  • 32
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    Development genes and evolution 204 (1994), S. 62-69 
    ISSN: 1432-041X
    Keywords: Cell determination ; direct development dorsoventral axis ; echinoids ; evolution
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    Topics: Biology
    Notes: Abstract In the direct-developing sea urchin Heliocidaris erythrogramma the first cleavage division bisects the dorsoventral axis of the developing embryo along a frontal plane. In the two-celled embryo one of the blastomeres, the ventral cell (V), gives rise to all pigmented mesenchyme, as well as to the vestibule of the echinus rudiment. Upon isolation, however, the dorsal blastomere (D) displays some regulation, and is able to form a small number of pigmented mesenchyme cells and even a vestibule. We have examined the spatial and temporal determination of cell fates along the dorsoventral axis during subsequent development. We demonstrate that the dorsoventral axis is resident within both cells of the two-celled embryo, but only the ventral pole of this axis has a rigidly fixed identity this early in development. The polarity of this axis remains the same in half-embryos developing from isolated ventral (V) blastomeres, but it can flip 180° in half-embryos developing from isolated dorsal (D) blastomeres. We find that cell fates are progressively determined along the dorsoventral axis up to the time of gastrulation. The ability of dorsal half-embryos to differentiate ventral cell fates diminishes as they are isolated at progressively later stages of development. These results suggest that the determination of cell fates along the dorsoventral axis in H. erythrogramma is regulated via inductive interactions organized by cells within the ventral half of the embryo.
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  • 33
    ISSN: 1423-0445
    Keywords: defensive secretion ; hot secretion ; elytral flanges ; evolution ; benzoquinones ; hydrocarbons ; bombardier beetle ; Coleoptera ; Carabidae ; Paussinae
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    Topics: Biology
    Notes: Summary The Australian bombardier beetle,Mystropomus regularis, sprays a mixture of quinones (1,4-benzoquinone, 2-methyl-1,4-benzoquinone, 2-ethyl-1,4-benzoquinone) and hydrocarbons (principallyn-pentadecane). The defensive fluid ist generated explosively in two-chambered glands, and is ejected audibly and hot (maximal recorded temperature = 59°C).Mystropomus is a member of the paussoid lineage of bombardiers. In common with other members of the group, it has a pair of elytral flanges (flanges of Coanda), associated with the gland openings, that serve as launching guides for anteriorly-aimed ejections of spray. It is argued thatMystropomus may be the least derived of flanged paussoids, and the closest living relative of the most primitive of extant bombardiers (Metriini).
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  • 34
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    Cellular and molecular life sciences 47 (1991), S. 791-803 
    ISSN: 1420-9071
    Keywords: Phytotoxins ; ecology ; phylogeny ; evolution ; biosynthesis ; coronatine ; phaseolotoxin ; rhizobitoxine ; syringomycin ; syringotoxin ; syringostatin ; tabtoxin ; tagetitoxin ; tropolone ; fireblight toxin ; thaxtomin ; 3-methylthiopropionic acid ; carboxylic acids ; Pseudomonas ; Xanthomonas ; Xanthomonas ; Streptomyces ; Erwinia ; Bradyrhizobium
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    Topics: Biology , Medicine
    Notes: Abstract This review attempts to rationalise what is known about bacterial phytotoxins and associate it with the ecology and possible evolution of the producing organisms. Study of non-toxin producing variants gives insight into the ecological role of the toxin. Elucidation of chemical structures of phytotoxins has shown that many exist as families of analogous compounds. Studies on the variation of chemical structures and how they are distributed across species and genera can lead to development of hypotheses on evolutionary relationships. Knowledge on biosynthetic pathways to tosins allows recognition of specific enzymatic steps involved in developing the characteristic features of the structures. Phytotoxins often have a potent biochemical activity, and in some cases the producing organism has associated mechanisms to prevent action of the toxin upon itself; in such cases toxigenesis is clearly not a chance event. The various aspects of bacterial toxigenesis indicate that bacterial phytotoxins are special secondary metabolic products that play beneficial roles to the producing organisms in their various ecological niches.
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  • 35
    ISSN: 1420-9071
    Keywords: Molluscan insulin-related peptides ; schistosomin ; neuropeptide gene family ; generation of neuropeptide diversity ; stimulus-dependent expression ; information-handling capacity ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We review recent experiments showing that the cerebral neuroendocrine Light Green Cells (LGCs) of the freshwater snail,Lymnaea stagnalis, express a family of distinct though related molluscan insulin-related peptide (MIP) genes. The LGCs are involved in the regulation of a wide range of interrelated life processes associated with growth, (energy) metabolism and reproduction. We consider the mechanism of generation of diversity among MIPs, and present evidence that conditions with distinct effects on growth, metabolism and reproduction also can induce distinct patterns of expression of the MIP and schistosomin genes. The stimulus-dependent expression of multiple neuropeptide genes enormously increases the adaptive potential of a peptidergic neuron. We suggest that this contributes significantly to the information-handling capacity of the brain.
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  • 36
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    Cellular and molecular life sciences 50 (1994), S. 5-14 
    ISSN: 1420-9071
    Keywords: parental investment ; juvenile survival ; evolution ; gastropods ; molluscs ; ovoviviparity ; viviparity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Parental care in terrestrial gastropods includes the of oviposition sites, production of large, heavily-yolked eggs supplied with calcium carbonate, provisioning of hatchings with eggs in specis with facultative sibling cannibalism, egg retention, and ovoviviparity. Evidence for true viviparity is scarce in terrestrial gastropods, as it is for postlaying care of eggs, though external egg carrying on the shell occurs in a few species. Care of young has not been observed in any terrestrial gastropod species. Provisioning of eggs with nutrients and calcium carbonate might be the most common form of parental investment. Ovoviviparity allows terrestrial gastropods to persist in habitats otherwise unsuitable for oviparous species (e.g. exposed rock walls). An interspecific comparison demonstrates that egg-retaining and ovoviviparous species produce smaller clutches than oviparous species and suggests a cost of parental care.
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  • 37
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    Plant cell reports 12 (1993), S. 293-297 
    ISSN: 1432-203X
    Keywords: Lycopersicon esculentum ; Genetic marker ; Intraspecific genetic map ; DNA polymorphism ; Isozyme ; RFLP ; RAPD
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The existing molecular genetic maps of the tomato, Lycopersicon spp, are constructed based on isozyme and RFLP polymorphisms between tomato species. These maps are useful for certain applications but have few markers that exhibit sufficient polymorphisms for intraspecific analysis and manipulations within the cultivated tomato. The purpose of this study was to investigate the relative potential of RAPD technology, as compared to isozymes and RFLPs, to generate polymorphic DNA markers within cultivated tomatoes. Sixteen isozymes and 25 RFLP clones that were known to detect polymorphism between L. esculentum and L. pennellii, and 313 random oligonucleotide primers were examined. None of the isozymes and only four of the RFLP clones (i.e., 16%) revealed polymorphism between the cultivated varieties whereas up to 63% of the RAPD primers detected one or more polymorphic DNA fragments between these varieties. All RAPD primers detected polymorphism between L. esculentum and L. pennellii genotypes. These results clearly indicate that RAPD technology can generate sufficient genetic markers exploiting sequence differences within cultivated tomatoes to facilitate construction of intraspecific genetic maps.
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  • 38
    ISSN: 1432-203X
    Keywords: Protoplast fusion ; RFLP ; Mitochondrial DNA ; Chloroplast DNA
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    Topics: Biology
    Notes: Summary Somatic hybrid plants were recovered following fusion of leaf mesophyll protoplasts isolated from tomato (Lycopersicon esculentum) cultivar UC82 with protoplasts isolated from suspension cultured cells of L. chilense, LA 1959. Iodoacetate was used to select against the growth of unfused tomato protoplasts. Two somatic hybrids were recovered in a population of 16 regenerants. No tomato regenerants were recovered; all of the non-hybrid regenerants were L. chilense. The L. chilense protoplast regenerants were tetraploid. The hybrid nature of the plants was verified using species-specific restriction fragment length polymorphisms for the nuclear, chloroplast and mitochondrial genomes. The somatic hybrids had inherited the chloroplast DNA of the tomato parent, and portions of the mitochondrial DNA of the L. chilense parent. The somatic hybrids formed flowers and developed seedless fruit.
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  • 39
    ISSN: 1432-2145
    Keywords: Gametophytic self incompatibilityself-compatibility ; Lycopersicon peruvianum Lycopersicon hirsutum ; S-associated proteins ; RFLP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Self-compatibility was investigated separately in two species of tomato, Lycopersicon peruvianum and L. hirsutum. The codominant expression of self-compatibility (SC)/self incompatibility (SI) was established using intraspecific hybrids of SC and SI hybrids. In SC L. peruvianum, a major stylar protein of approximately 29 kDa cosegregates with self-compatibility in the progeny of SC/SI hybrids. The SC/SI hybrids are self-fertile, but only partially so, since the SI allele present in the hybrids is capable of eliminating certain genotypes in the resultant progeny. In L. hirsutum, the majority of hybrids between one accession of SI L. hirsutum f. hirsutum and one of SC L. hirsutum f. glabratum are self-fertile. Analysis of the progeny revealed that the SC and SI alleles are codominant in this species as well. A protein product for the SC allele is not obvious in style extracts of L. hirsutum f. glabratum. Segregating progeny from SC/SI hybrids of L. hirsutum were used to map the S locus against five RFLP markers on chromosome 1, and estimated map distances are given. In addition, evidence is presented that indicates that one of the DNA markers, CD15, is duplicated in L. hirsutum f. glabratum, and the duplication is not linked to the S locus.
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  • 40
    ISSN: 1432-203X
    Keywords: Rice (Oryza sativa) ; Genetic Marker ; Genetic Map ; Integrated Linkage Map ; RFLP
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    Topics: Biology
    Notes: Abstract Application of genetic linkage maps in plant genetics and breeding can be greatly facilitated by integrating the available classical and molecular genetic linkage maps. In rice, Oryza sativa L., the classical linkage map includes about 300 genes which correspond to various important morphological, physiological, biochemical and agronomic characteristics. The molecular maps consist of more than 500 DNA markers which cover most of the genome within relatively short intervals. Little effort has been made to integrate these two genetic maps. In this paper we report preliminary results of an ongoing research project aimed at the complete integration and alignment of the two linkage maps of rice. Six different F2 populations segregating for various phenotypic and RFLP markers were used and a total of 12 morphological and physiological markers (Table 1) were mapped onto our recently constructed molecular map. Six linkage groups (i.e., chr. 1, 3, 7, 9, 11 and 12) on our RFLP map were aligned with the corresponding linkage groups on the classical map, and the previous alignment for chromosome 6 was further confirmed by RFLP mapping of an additional physiological marker on this chromosome. Results from this study, combined with our previous results, indicate that, for most chromosomes in rice, the RFLP map encompasses the classical map. The usefulness of an integrated genetic linkage map for rice genetics and breeding is discussed.
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    Current genetics 26 (1994), S. 456-460 
    ISSN: 1432-0983
    Keywords: Parasitella parasitica ; Zygomycetes ; RAPD ; PCR ; RFLP ; Electrophoretic karyotype ; Molecular taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In addition to conventional methods for the identification of fungi, molecular techniques at the DNA level are increasingly being employed. In order to check the validity of such experimental approaches, we have analyzed the well-defined species Parasitella parasitica, which belongs to the family Mucoraceae (Mucorales, Zygometes). The seven strains of this species, which are available from international strain collections, were analyzed by several molecular methods: restriction fragment length polymorphism analysis (RFLP), the random primer-dependent polymerase chain reaction (RAPD-PCR), and electrophoretic karyotyping. Unexpectedly, these strains are highly diverse at the molecular level. By these techniques they can be divided consistently into two different groups. Nevertheless, all seven strains belong to a single species. They show no morphological differences and sexual spores (zygospores) were found in all possible combinations either within or between the two groups. Southern-blot analysis of genomic DNA of all P. parasitica strains with RAPD-PCR-derived labelled probes shows the existence of repetitive elements characteristic for only one group of P. parasitica. In addition, chromosome sizes, which were separated by rotating-field electrophoresis, were highly divergent, and ranged from 3 to 6.5 Mb in one group and between 2 and 4.5 Mb in the other. The RAPD-PCR patterns also discriminate both groups of P. parasitica. However, they are very similar if strains of a single group are compared. Therefore, we propose that the determination of fungal species by molecular techniques should be vetted at least by morphological and physiological parameters and, whenever possible, by mating experiments.
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  • 42
    ISSN: 1432-0983
    Keywords: Cytoplasmic male sterility ; Antisense RNA ; RFLP ; Cybrids
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    Topics: Biology
    Notes: Abstract Asymmetric cell-fusion of the japonica cultivar ofOryza sativa (rice) with cytoplasmic-male-sterile (CMS) plants bearing cytoplasm derived from Chinsurah Boro II, resulted in two classes of cytoplasmic hybrids (cybrids), fertile and CMS. Southern-blot analysis of the mitochondrial DNA (mtDNA) indicates recombination events around a number of genes; however, the appearance of the CMS character is tightly correlated to reorganization around theatp6 gene, suggesting recombination downstream from theatp6 gene is involved in CMS. The nucleotide sequence downstream fromatp6 contains a pseudogene which was probably created by recombination of the mitochondrial genome. Sense and antisense transcripts of the downstream region ofatp6 were found in CMS-and restored CMS (fertile)-lines, but not in the normal (fertile) line. In the CMS line, several antisense transcripts of theatp6 gene were also found. However, in the restored line which contains a nuclear-encoded gene,Rf-1, the levels of these transcripts were lower than in the CMS line. These results suggest abnormal transcripts of theatp6 gene produced in the antisense direction may be involved in CMS, and that products of the nuclear-encoded restorer gene may reduce abnormal transcription in this region of the mitochondrial genome.
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  • 43
    ISSN: 1432-0983
    Keywords: DNA fingerprinting of Trichoderma ; Trichoderma reesei ; RFLP ; Strain classification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have analyzed nine different species of the filamentous fungus Trichoderma and three strains of T. reesei for the presence of hypervariable loci in their genomes by hybridization with simple repeat oligonucleotides [(CT)8, (GTG)5, and (GACA)4]. On the basis of the DNA-fingerprints obtained, the Trichoderma aggregate is re-classified into five groups: I (T. reesei, T. todica), II (T. polysporum, T. longibrachiatum, T. koningii, and T. pseudokoningii), III (T. virgatum), IV (T. saturnisporum) and V (T. harzianum). These results contradict the claim that T. reesei is a subspecies of T. longibrachiatum. Furthermore, hybridization with (CA)8 allowed a subdivision of group II, wherein T. pseudokoningii formed a subgroup, IIb, which is highly homologous with, but distinct from subgroup IIa. The results show that RFLP analysis may be used to re-classify the Trichoderma aggregate.
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    Molecular engineering 1 (1992), S. 377-399 
    ISSN: 1572-8951
    Keywords: Origin of life ; molecular engineering ; biology ; evolution ; genetic code ; translation machine ; self instruction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In attempting to understand how life originated, we search for a detailed sequence of experimentally testable physico-chemical steps in an appropriately structured system. This goal is approached in two stages. First we search for the organizational structure of processes leading to systems with the basic features of living organisms. This is an engineering problem: finding a certain construct by taking care of logical requirements and restrictions from physics. Then we face this construct with the chemical and geophysical reality, and this leads to the view that systems with the essential features of early living organisms evolve following a distinct pathway. Energy supply and the presence of a particular structure in space and time are necessary to induce and drive the processes triggered by stochastic events; but if these particular conditions are given, the broad line of the evolutionary processes is determined by logical requirements and by chemical and geophysical constrains and invariants. The genetic machinery considered to evolve in this manner agrees, in its organizational structure and in many details, with the actual genetic machinery of biosystems. A surprising simplicity and transparency is observed in the logic of the basic processes involved in the origin of life. In the present view, the processes leading to the origin of life begin in a very particular, highly structured, small region where the relevant chemistry can be quite different from overall prebiotic chemistry. Energy-rich compounds are present in ample amounts and a succession of physico-chemical processes, which are per se thermodynamically allowed, takes place. This is in contrast to popular views that the origin of life is connected with fundamental thermodynamic questions related to the problem of getting order out of chaos.
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  • 45
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    Behavior genetics 20 (1990), S. 109-126 
    ISSN: 1573-3297
    Keywords: Y chromosome ; DNA ; mammals ; evolution ; behavior
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract There is a predominant theory for the evolution of the mammalian Y chromosome. This theory hypothesizes that genes for sex determination and male-specific traits, as well as sequences for X-Y meiotic pairing, are conserved on the mammalian Y chromosome across all lineages and that all other Y chromosomal genes or sequences have been or will be lost in each mammalian lineage. There are effects of mouse Y chromosomal genes on behaviors and other traits that are not male specific. Under the predominant theory, these Y chromosomal genes could be the same as the conserved genes for sex determination or malespecific traits, or they could be genes that have been lost from the Y chromosomes of other mammalian lineages and that will eventually be lost from the Y chromosome of the rodent lineage. Recently, the evolution of the primate and rodent Y chromosomes has been studied at the DNA level. These studies are summarized and reviewed in this article. The findings of these studies are not fully consistent with the predominant theory for the evolution of the mammalian Y chromosome. Also, they imply that there are other possibilities for the phylogenetic history of Y chromosomal genes of mice with effects on behavior. These are that Y chromosomal genes with effects on mouse behaviors or other traits could be conserved genes other than those for sex determination or malespecific traits or that they could be novel genes on the Y chromosome of the rodent orMus lineage.
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  • 46
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    Biochemical genetics 28 (1990), S. 209-222 
    ISSN: 1573-4927
    Keywords: glycophorin A ; glycophorin B ; evolution ; primates ; chimpanzee ; gorilla ; orangutan ; gibbon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Analysis of nucleotide sequences of the human glycophorin A (GPA) and glycophorin B (GPB) genes has indicated that the GPA gene most closely resembles the ancestral gene, whereas the GPB gene likely arose from the GPA gene by homologous recombination. To study the evolution of the glycophorin gene family in the hominoid primates, restricted DNA on Southern blots from man, pygmy chimpanzee, common chimpanzee, gorilla, orangutan, and gibbon was probed with cDNA fragments encoding the human GPA and GPB coding and 3′-untranslated regions. This showed the presence in all of the hominoid primates of at least one GPA-like gene. In addition, at least one GPB-like gene was detected in man, both chimpanzee species, and gorilla, strongly suggesting that the event that produced the GPB gene occurred in the common ancestor of man-chimpanzee-gorilla. An unexpected finding in this study was the conservation ofEcoRI restriction sites relative to those of the other four enzymes used; the significance of this observation is unclear, but raises the question of nonrandomness ofEcoRI restriction sites in noncoding regions. Further analysis of the evolution of this multigene family, including nucleotide sequence analysis, will be useful in clarification of the evolutionary relationships of the hominoid primates, in correlation with the structure and function of the glycophorin molecules, and in assessment of the role of evolution in the autogenicity of glycophorin determinants.
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  • 47
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    Molecular and cellular biochemistry 138 (1994), S. 25-32 
    ISSN: 1573-4919
    Keywords: NAD ; evolution ; polymerase chain reaction ; zinc finger ; leucine zipper
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    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Poly(ADP-ribose) polymerase cDNAs have been isolated from different classes of animals. Cloning of genes from lower eukaryotes has allowed us to investigate directly the biological functions of poly(ADP-ribosyl)ationin vivo. The conservation of specific regions among mammals, chicken,Xenopus laevis, andDrosophila melanogaster reveals the essential structural elements required for recognition of breaks in DNA and for catalytic activity. Cys, His and basic residues in the zinc-finger consensus region are conserved. The carboxyl terminal region corresponding to an NAD-binding domain is strongly conserved. The dinucleotide-binding consensus sequence and β1-αA-β2, Rossmann fold structure, and β-sheet structures are completely conserved from mammals to insect. InDrosophila, a putative leucine-zipper motif has been identified, and other poly(ADP-ribose) polymerases also contain an α-helical, amphipathic structure in the auto-modification domain. In this article, we review the recent structural analyses of the functional domains of poly(ADP-ribose) polymerase in phylogenetically divergent species, and discuss the implications of structural conservation for its biological functions.
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  • 48
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    Biochemical genetics 28 (1990), S. 337-346 
    ISSN: 1573-4927
    Keywords: glutamate dehydrogenase ; Drosophila melanogaster ; gene expression ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract We have isolated theDrosophila melanogaster locus coding forl-glutamate dehydrogenase (EC 1.4.1.3) by virtue of its similarity to the corresponding human gene. There is only one copy of this gene in the fruit fly genome, located on the right arm of chromosome 3 (95D1-4). The transcript includes at least one large intron and matures to a ∼2.4-kb-long polyadenylated RNA whose expression is under developmental control.
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  • 49
    ISSN: 1573-4927
    Keywords: restriction fragment length polymorphisms ; glycophorin A ; glycophorin B ; MN blood group ; V-A-B-D blood group ; Vc antigen ; chimpanzee ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Twelve restriction fragment length polymorphisms (RFLPs) were detected in common chimpanzee using two restriction enzymes (HindIII andMspI) and four DNA probes to the coding regions of the human glycophorin A (GPA) and glycophorin B (GPB) genes and their 3′-untranslated regions. Seven RFLPs correlated with red cell expression of the Vc determinant of the MN blood group-related V-A-B-D system and five RFLPs correlated with nonexpression of this antigen. Animals heterozygous for theV allele that encodes the Vc determinant had all 12 polymorphic restriction fragments and appeared to show reduced intensity of probe hybridization to these fragments, consistent with the presence of aV and a non-V allele. No RFLPs were detected withEcoRI,SstI, orBamHI, in spite of the relatively large segment of DNA (at least 20 kb) involved in the polymorphisms. The RFLPs were chimpanzee specific and were not found in man, gorilla, orangutan, or gibbon. Multiple RFLPs distinguishing primate species are rare and may be useful markers for molecular evolution.
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    Molecular and cellular biochemistry 133-134 (1994), S. 245-262 
    ISSN: 1573-4919
    Keywords: creatine kinase ; arginine kinase ; protein sequence comparison ; evolution ; CK framework ; ‘diagnostic boxes’ ; secondary structure prediction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Comparisons of the protein sequences and gene structures of the known creatine kinase isoenzymes and other guanidino kinases revealed high homology and were used to determine the evolutionary relationships of the various guamidino kinases. A ‘CK framework’ is defined, consisting of the most conserved sequence blocks, and ‘diagnostic boxes’ are identified which are characteristic for anyone creatine kinase isoenzyme (e.g. for vertebrate B-CK) and which may serve to distinguish this isoenzyme from all others (e.g. from M-CKs and Mi-CKs). Comparison of the guanidino kinases by near-UV and far-UV circular dichroism further indicates pronounced conservation of secondary structure as well as of aromatic amino acids that are involved in catalysis.
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  • 51
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    Journal of chemical ecology 20 (1994), S. 231-238 
    ISSN: 1573-1561
    Keywords: Trichoplusia ni ; Lepidoptera ; Noctuidae ; sex pheromone ; behavior ; evolution ; sexual selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Male cabbage looper moths,Trichoplusia ni, from two colonies in which all females express an abnormal sex pheromone production phenotype were evaluated in a laboratory wind tunnel for upwind flight responses to the normal and abnormal sex pheromones. The abnormal sex pheromone blend consisted of 20 times as much (Z)-9-tetradecenyl acetate and 30-fold less (Z)-5-dodecenyl acetate compared to the normal pheromone blend. Initially, these males exhibited poor behavioral responses to the abnormal sex pheromone and maximum responses to the normal pheromone blend, indicating that there was no linkage between signal production and response. After 49 generations of laboratory rearing, males from the mutant colonies maintained good responses to the normal pheromone and increased their behavioral response to the abnormal sex pheromone to the same levels as for the normal pheromone. Over the same period, normal males maintained their preference for the normal pheromone. These results indicated that evolution had occurred in mutant colonies in favor of greater male responsiveness to the abnormal sex pheromone, resulting in the broadening of the response spectrum to pheromone blend ratios. This evolution presumably resulted from a mating advantage to those males that did not discriminate against mutant-type females in the mutant colonies.
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  • 52
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    Biochemical genetics 28 (1990), S. 337-346 
    ISSN: 1573-4927
    Keywords: glutamate dehydrogenase ; Drosophila melanogaster ; gene expression ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract We have isolated theDrosophila melanogaster locus coding forl-glutamate dehydrogenase (EC 1.4.1.3) by virtue of its similarity to the corresponding human gene. There is only one copy of this gene in the fruit fly genome, located on the right arm of chromosome 3 (95D1-4). The transcript includes at least one large intron and matures to a ∼2.4-kb-long polyadenylated RNA whose expression is under developmental control.
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  • 53
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    Behavior genetics 20 (1990), S. 563-568 
    ISSN: 1573-3297
    Keywords: personality ; fertility ; family size ; fitness ; extraversion ; neuroticism ; impulsivity ; genetic architecture ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract The relationship between reproductive success (number of biological children) and personality was explored in 1101 postmenopausal females from the Australian twin registry. The quadratic response surface relating fitness to extraversion (E) and neuroticism (N) showed a saddle point at intermediate levels of E and N. Selection was shown to be stabilizing, i.e.,having an intermediate optimum, along the axis low E, low N-high E, high N and more mildly disruptive, having greater fitness in the extremes, along the axis low N, high E-high N, low E. Neither dimension of personality considered by itself showed a significant linear or quadratic relationship to reproductive success. Sections through the fitness surface, however, show selection tends to favor high neuroticism levels in introverts and low neuroticism levels in extroverts.
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  • 54
    ISSN: 1573-5028
    Keywords: Angiopteris lygodiifolia ; atpB ; chloroplast genome ; evolution ; rbcL ; trnR
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    Topics: Biology
    Notes: Abstract To elucidate the evolutionary relationship between the Spermatophyta, Pteridophyta and Bryophyta, we cloned a fragment of chloroplast DNA from the fernAngiopteris lygodiifolia (Pteridophyta) and determined its nucleotide sequence. The fragment contained theatpB,rbcL,trnR-CCG,dedB andpsaI genes. Comparisons of the deduced amino acid and nucleotide sequences of these genes from the three plant groups indicate thatAngiopteris sequences are more closely related to those of Bryophyta species (85% identity on average) than to those of seed plants (76% identity on average), supporting a hypothesis that the Bryophyta and Pteridophyta diverged more recently from one another than their common progenitor diverged from that of the Spermatophyta.
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  • 55
    ISSN: 1573-5028
    Keywords: translation elongation factor genes ; promoter analysis ; evolution
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    Topics: Biology
    Notes: Abstract In Arabidopsis thaliana, the activation process of the A1 EF-1α gene depends on several elements. Using the GUS reporter gene, transient expression experiments have shown that mutations of upstream cis-acting elements of the A1 promoter, or the deletion of an intron located within the 5′ non-coding region, similarly affect expression in dicot or monocot protoplasts. The results reported here strongly suggest that this 5′ intron is properly spliced in Zea mays. We show that two trans-acting factors, specifically interacting with an upstream activating sequence (the TEF 1 box), are present in nuclear extracts prepared from A. thaliana, Brassica rapa, Nicotiana tabacum and Z. mays. In addition, a DNA sequence homologous to the TEF 1 box, found at approximately the same location within a Lycopersicon esculentum EF-1α promoter, interacts with the same trans-acting factors. Homologies found between the A. thaliana and L. esculentum TEF 1 box sequences have allowed us to define mutations of this upstream element which affect the interaction with the corresponding trans-acting factors. These results support the notion that the activation processes of A. thaliana EF-1α genes have been conserved among angiosperms and provide interesting data on the functional structure of the TEF 1 box.
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  • 56
    ISSN: 1573-5028
    Keywords: carboxy-terminal processing ; glycosylation ; Hordeum vulgare L. ; Prx locus ; RFLP ; signal peptide ; targeting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The major peroxidase of barley seed BP 1 was characterized. Previous studies showed a low carbohydrate content, low specific activity and tissue-specific expression, and suggested that this basic peroxidase could be particularly useful in the elucidation of the structure-function relationship and in the study of the biological roles of plant peroxidases (S.K. Rasmussen, K.G. Welinder and J. Hejgaard (1991) Plant Mol Biol 16: 317–327). A cDNA library was prepared from mRNA isolated from seeds 15 days after flowering. Full-length clones were obtained and showed 3′ end length variants, a G+C content of 69% in the translated region, a 90% G or C preference in the wobble position of the codons and a typical signal peptide sequence. N-terminal amino acid sequencing and sequence analysis of tryptic peptides verified 98% of the sequence of the mature BP 1 which contains 309 amino acid residues. BP 1 is the first characterized plant peroxidase which is not blocked by pyroglutamate. BP 1 polymorphism was observed. BP 1 is less than 50% identical to other plant peroxidases which, taken together with its developmentally dependent expression in the endosperm 15–20 days after flowering, suggests a unique biological role of this enzyme. The barley peroxidase is processed at the C-terminus and might be targeted to the vacuole. The single site of glycosylation is located near the C-terminus in the N-glycosylation sequon -Asn-Cys-Ser- in which Cys forms part of a disulphide bridge. The major glycan is a typical plant modified-type structure, Manα1-6(Xylβ1-2)Manβ1-4GlcNAcβ1-4(Fucα1-3)GlcNAc. The BP 1 gene was RFLP-mapped on barley chromosome 3, and we propose Prx5 as the name for this new peroxidase locus.
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  • 57
    ISSN: 1573-5028
    Keywords: gene duplication ; photosynthesis ; RFLP ; Southern blots
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    Topics: Biology
    Notes: Abstract A second locus (Lhb1B) encoding Photosystem II Type I chlorophyll a/b-binding (CAB) polypeptides was identified in Arabidopsis thaliana. This locus carries two genes in an inverted orientation. The predicted sequences of the polypeptides encoded by these two genes show substantial divergence in their amino termini relative to each other and to the proteins encoded by the three Lhb1 CAB genes previously characterized [10], but little divergence within the predicted primary structure of the mature protein. DNA probes derived from seven additional types of tomato CAB genes, encoding chlorophyll a/b-binding polypeptides of several antenna systems of the photosynthetic apparatus, were tested against A. thaliana. Each of these hybridized in Southern blots to unique DNA fragment(s), demonstrating the existence of each of these different types of CAB genes in the genome of A. thaliana. The number of genes encoding each CAB type in A. thaliana was estimated to be similar to that of tomato.
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  • 58
    ISSN: 1573-5028
    Keywords: bark storage protein ; gene clustering ; RFLP ; systemic response
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two wound-inducible cDNAs from poplar leaves show sequence identity to vegetative storage proteins (VSP) that accumulate seasonally in poplar bark tissues. We have compared the genomic organization, cDNA sequences and expression of the genes encoding the wound-inducible cDNAs (win4) with that of a bark VSP (called bark storage protein, or BSP). There appear to be several win4 genes in the poplar genome which segregate as a single locus and are therefore likely to be clustered. The same is true of the BSP genes. The win4 locus is linked (map distance of 5 cM) to the BSP locus, consistent with a common evolutionary origin of the genes. A near full-length win4 cDNA shows 75% sequence identity to BSP cDNAs. Both win4 and BSP are systemically wound-inducible; win4 transcripts accumulate in leaves and stems, whereas BSP transcripts accumulate almost exclusively in stems. A phloem transport-dependent signaling mechanism appears to be involved in systemic win4 expression after wounding. In contrast to BSP gene expression, win4 genes are not expressed in response to short day conditions. The data indicate win4 and BSP genes are differentially regulated, and their products may play important roles in the storage and reallocation of nitrogen in perennial plants.
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    Plant molecular biology 23 (1993), S. 409-413 
    ISSN: 1573-5028
    Keywords: cDNA ; cloning ; rice ; L5 ; ribosomal 5 S RNA-binding protein ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A rice (Oryza sativa L.) cDNA clone coding for the cytoplasmic ribosomal protein L5, which associates with 5 S rRNA for ribosome assembly, was cloned and its nucleotide sequence was determined. The primary structure of rice L5, deduced from the nucleotide sequence, contains 294 amino acids and has intriguing features some of which are also conserved in other eucaryotic homologues. These include: four clusters of basic amino acids, one of which may serve as a nucleolar localization signal; three repeated amino acid sequences; the conservation of glycine residues. This protein was identified as the nuclear-encoded cytoplasmic ribosomal protein L5 of rice by sequence similarity to other eucaryotic ribosomal 5 S RNA-binding proteins of rat, chicken, Xenopus laevis, and Saccharomyces cerevisiae. Rice L5 shares 51 to 62% amino acid sequence identity with the homologues. A group of ribosomal proteins from archaebacteria including Methanococcus vanniellii L18 and Halobacterium cutirubrum L13, which are known to be associated with 5 S rRNA, also related to rice L5 and the other eucaryotic counterparts, suggesting an evolutionary relationship in these ribosomal 5 S RNA-binding proteins.
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  • 60
    ISSN: 1573-5028
    Keywords: Cyanidium caldarium Geitler ; evolution ; Galdieria sulphuraria ; inverted repeat ; plastid DNA ; psbD-psbC operon ; red algae ; 5S rRNA ; rpl21 ; rps16
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The four inverted repeat (IR) flanking regions of the Cyanidium caldarium plastid DNA were cloned. Southern blotting, transcript and sequence analyses of the border regions revealed the psbD-psbC operon and the rps16 gene within the large single-copy region upstream of the 16S rDNA gene and the rpl21 gene downstream of the 5S rDNA within the 16 kb small single-copy region. The size of the IR is ca. 5 kb. The nucleotide sequences of the psbD-psbC, rps16, rpl21 and 5S rRNA genes with the corresponding alignments and physical maps of the regions are presented. Northern analysis revealed a less complex psbD-psbC transcription pattern than has been found in higher plants. Comparisons to other red algal data point to structural diversity within red algal plastid DNA.
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  • 61
    ISSN: 1573-5028
    Keywords: higher plants ; sunflower ; chloroplast genome ; mitochondrial genome ; tRNAHis genes ; evolution
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  • 62
    ISSN: 1573-5028
    Keywords: aspartate aminotransferase ; gene structure ; nodule ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Genomic clones encoding two isozymes of aspartate aminotransferase (AAT) were isolated from an alfalfa genomic library and their DNA sequences were determined. The AAT1 gene contains 12 exons that encode a cytosolic protein expressed at similar levels in roots, stems and nodules. In nodules, the amount of AAT1 mRNA was similar at all stages of development, and was slightly reduced in nodules incapable of fixing nitrogen. The AAT1 mRNA is polyadenylated at multiple sites differing by more than 250 bp. The AAT2 gene contains 11 exons, with 5 introns located in positions identical to those found in animal AAT genes, and encodes a plastid-localized isozyme. The AAT2 mRNA is polyadenylated at a very limited range of sites. The transit peptide of AAT2 is encoded by the first two and part of the third exon. AAT2 mRNA is much more abundant in nodules than in other organs, and increases dramatically during the course of nodule development. Unlike AAT1, expression of AAT2 is significantly reduced in nodules incapable of fixing nitrogen. Phylogenetic analysis of deduced AAT proteins revealed 4 separate but related groups of AAT proteins; the animal cytosolic AATs, the plant cytosolic AATs, the plant plastid AATs, and the mitochondrial AATs.
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    Plant molecular biology 21 (1993), S. 99-108 
    ISSN: 1573-5028
    Keywords: fusion protein ; Oenothera ; plastome ; RFLP ; unidentified open reading frame
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The chloroplast DNA encodes genes for components of photosynthesis and the transcription-translation machinery; a number of unidentified open reading frames (ORFs) are also present. To determine whether a large ORF in the inverted repeat of chloroplast DNA of tobacco (ORF2280) encodes a chloroplast protein, a conserved region of the ORF was expressed in Escherichia coli. An antibody against the ORF protein was prepared using the purified fusion protein as an antigen. When incubated with proteins from the soluble fraction of tobacco, spinach and Oenothera chloroplasts, the antiserum detects relatively labile polypeptides, which have apparent molecular weights of 170 to 180 kDa. The ORF in tobacco and spinach is large enough to encode a protein of 240–250 kDa, thus it is possible that post-transcriptional or post-translational processing reduces the size of the expression product. Analysis of Oenothera chloroplasts representing four different plastome types revealed endonuclease restriction fragment length polymorphisms in chloroplast DNA indicative of insertion/deletion events in a region of the chloroplast DNA that shared significant sequence similarity with ORF2280. The ORF2280 antiserum was used to demonstrate that there are qualitative differences in the ORF proteins from different Oenothera plastome types.
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  • 64
    ISSN: 1573-5028
    Keywords: cDNA sequences ; evolution ; fructose-1,6-bisphosphate aldolase ; Spinacia oleracea ; transit peptide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We report the sequences of full-length cDNAs for the nuclear genes encoding the chloroplastic and cytosolic fructose-1,6-bisphosphate aldolase (EC 4.1.2.13) from spinach. A comparison of the deduced amino-acid sequences with one another and with published cytosolic aldolase sequences of other plants revealed that the two enzymes from spinach share only 54% homology on their amino acid level whereas the homology of the cytosolic enzyme of spinach with the known sequences of cytosolic aldolases of maize, rice and Arabidopsis range from 67 to 92%. The sequence of the chloroplastic enzyme includes a stroma-targeting N-terminal transit peptide of 46 amino acid residues for import into the chloroplast. The transit peptide exhibits essential features similar to other chloroplast transit peptides. Southern blot analysis implies that both spinach enzymes are encoded by single genes.
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  • 65
    ISSN: 1573-5028
    Keywords: C4 metabolism ; evolution ; GC content ; gene family ; PEPC ; Sorghum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Although housekeeping functions have been shown for the phosphoenolpyruvate carboxylase (EC 4.1.1.31, PEPC) in plants and in prokaryotes, PEPC is mainly known for its specific role in the primary photosynthetic CO2 fixation in C4 and CAM plants. We have shown that in Sorghum, a monocotyledonous C4 plant, the enzyme is encoded in the nucleus by a small multigene family. Here we report the entire nucleotide sequence (7.5 kb) of the third member (CP21) that completes the structure of the Sorghum PEPC gene family. Nucleotide composition, CpG islands and GC content of the three Sorghum PEPC genes are analysed with respect to their possible implications in the regulation of expression. A study of structure/function and phylogenetic relationships based on the compilation of all PEPC sequences known so far is presented. Data demonstrate that (1) the different forms of plant PEPC have very similar primary structures, functional and regulatory properties, (2) neither apparent amino acid sequences nor phylogenetic relationships are specific for the C4 and CAM PEPCs and (3) expression of the different genes coding for the Sorghum PEPC isoenzymes is differently regulated (i.e. by light, nitrogen source) in a spatial and temporal manner. These results suggest that the main distinguishing feature between plant PEPCs is to be found at the level of genes expression rather than in their primary structure.
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    Biochemical genetics 31 (1993), S. 473-484 
    ISSN: 1573-4927
    Keywords: hydroxyacyl glutathione hydrolase (glyoxalase II) ; chromosome mapping ; evolution ; Mus musculus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In man, the gene for hydroxyacyl glutathione hydrolase (HAGH; glyoxalase II) is closely linked to the α-globin locus (HBα) on Chromosome 16. HAGH polymorphism in the mouse has now enabled the mapping of the murine homologue. Deletion mapping, congenic strain studies, and characterization of 41 recombinant inbred strains establish that the mouseHagh locus lies very close to the α-globin pseudogene (Hba-ps4) in the vicinity of the major histocompatibility locus (H-2) on chromosome 17. Several other loci have been identified previously that are also closely linked to the human α-globin locus but near the α-globin pseudogeneHba-ps4 in the mouse. These linkage relationships suggest that during the evolution of mice a translocation occurred that subdivided the α-globin locus, leaving one inactive α-globin gene still associated with theHagh locus and linked sequences, while moving and inserting the active α-globin locus and all distal sequences into an internal location on another autosome, the predecessor to mouse chromosome 11.
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    Biochemical genetics 31 (1993), S. 329-341 
    ISSN: 1573-4927
    Keywords: actin superfamily ; Drosophila genetics ; ATPase domain ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Diverse proteins that are 35% to 55% identical to actins have been discovered recently in yeasts, nematodes, and vertebrates. In order to study these proteins systematically and relate their functions to those of conventional actins, we are isolating the corresponding genes from the genetically tractable eukaryote,Drosophila melanogaster. Here we report the isolation and partial characterization of aDrosophila homologue of theSchizosaccharomyces pombe act2 gene. Degenerate oligonucleotide primers specifying peptides that are highly conserved within the actin protein superfamily were used in conjunction with polymerase chain reaction (PCR) to amplify a portion of theDrosophila gene that we have namedactr66B. The corresponding full-length cDNA sequence encodes a protein of 418 residues that is 65% identical to the product of theS. pombe act2 gene, 80% identical to the bovineact2 homologue, but only 48% identical to the principalDrosophila cytoplasmic actin encoded by theAct5C actin gene. Alignment of the yeast, bovine, andDrosophila actin-related proteins shows that they have four peptide insertions, relative to conventional actins, three of which are well placed to modify actin polymerization and one that is likely to perturb the binding of myosin. Locations of two of the fiveactr66B introns are conserved betweenDrosophila and yeast genes, further attesting that they evolved from a common ancestor and are likely to encode proteins having similar functions. We demonstrate that theDrosophila gene is located on the left arm of chromosome 3, within subdivision 66B. Finally, we show by RNA blot-hybridization that the gene is expressed at low levels, relative to conventional nonmuscle actin, in all developmental stages. From these and other observations we infer that the actr66B protein is a minor component of all cells, perhaps serving to modify the polymerization, structure, and dynamic behavior of actin filaments.
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  • 68
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    Biochemical genetics 31 (1993), S. 473-484 
    ISSN: 1573-4927
    Keywords: hydroxyacyl glutathione hydrolase (glyoxalase II) ; chromosome mapping ; evolution ; Mus musculus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In man, the gene for hydroxyacyl glutathione hydrolase (HAGH; glyoxalase II) is closely linked to the α-globin locus (HBα) on Chromosome 16. HAGH polymorphism in the mouse has now enabled the mapping of the murine homologue. Deletion mapping, congenic strain studies, and characterization of 41 recombinant inbred strains establish that the mouseHagh locus lies very close to the α-globin pseudogene (Hba-ps4) in the vicinity of the major histocompatibility locus (H-2) on chromosome 17. Several other loci have been identified previously that are also closely linked to the human α-globin locus but near the α-globin pseudogeneHba-ps4 in the mouse. These linkage relationships suggest that during the evolution of mice a translocation occurred that subdivided the α-globin locus, leaving one inactive α-globin gene still associated with theHagh locus and linked sequences, while moving and inserting the active α-globin locus and all distal sequences into an internal location on another autosome, the predecessor to mouse chromosome 11.
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  • 69
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    Biochemical genetics 31 (1993), S. 329-341 
    ISSN: 1573-4927
    Keywords: actin superfamily ; Drosophila genetics ; ATPase domain ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Diverse proteins that are 35% to 55% identical to actins have been discovered recently in yeasts, nematodes, and vertebrates. In order to study these proteins systematically and relate their functions to those of conventional actins, we are isolating the corresponding genes from the genetically tractable eukaryote,Drosophila melanogaster. Here we report the isolation and partial characterization of aDrosophila homologue of theSchizosaccharomyces pombe act2 gene. Degenerate oligonucleotide primers specifying peptides that are highly conserved within the actin protein superfamily were used in conjunction with polymerase chain reaction (PCR) to amplify a portion of theDrosophila gene that we have namedactr66B. The corresponding full-length cDNA sequence encodes a protein of 418 residues that is 65% identical to the product of theS. pombe act2 gene, 80% identical to the bovineact2 homologue, but only 48% identical to the principalDrosophila cytoplasmic actin encoded by theAct5C actin gene. Alignment of the yeast, bovine, andDrosophila actin-related proteins shows that they have four peptide insertions, relative to conventional actins, three of which are well placed to modify actin polymerization and one that is likely to perturb the binding of myosin. Locations of two of the fiveactr66B introns are conserved betweenDrosophila and yeast genes, further attesting that they evolved from a common ancestor and are likely to encode proteins having similar functions. We demonstrate that theDrosophila gene is located on the left arm of chromosome 3, within subdivision 66B. Finally, we show by RNA blot-hybridization that the gene is expressed at low levels, relative to conventional nonmuscle actin, in all developmental stages. From these and other observations we infer that the actr66B protein is a minor component of all cells, perhaps serving to modify the polymerization, structure, and dynamic behavior of actin filaments.
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  • 70
    ISSN: 1573-4943
    Keywords: Calcium-binding lysozyme ; α-lactalbumin ; three-dimensional structure ; evolution
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    Topics: Chemistry and Pharmacology
    Notes: Abstract Similarities in amino acid sequences, three-dimensional structures, and the exon-intron patterns of their genes have indicated thatc-type lysozymes andα-lactalbumins are homologous proteins, i.e., descended by divergent evolution from a common ancestor. Like theα-lactalbumins, echidna milk, horse milk, and pigeon eggwhite lysozymes all bind Ca(II). Models of their three-dimensional structures, based on their amino acid sequences and the known crystal structures of domestic hen eggwhite and human lysozymes and baboon and humanα-lactalbumins, have been built. The several structures have been compared and their relationships discussed.
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  • 71
    ISSN: 1573-5028
    Keywords: retrotransposon ; Pisum ; segregation ; PCR ; RFLP ; mapping
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    Topics: Biology
    Notes: Abstract A DNA sequence between two legumin genes in Pisum is a member of the copia-like class of retrotransposons and represents one member of a polymorphic and heterogeneous dispersed repeated sequence family in Pisum. This sequence can be exploited in genetic studies either by RFLP analysis where several markers can be scored together, or the segregation of individual elements can be followed after PCR amplification of specific members.
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  • 72
    ISSN: 1573-5028
    Keywords: Agrobacterium tumefaciens ; Ti plasmid ; evolution ; IS elements ; host range
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    Topics: Biology
    Notes: Abstract The TA regions of biotype III octopine/cucumopine (OC) Ti plasmids are closely related to the TL region of the biotype I octopine Ti plasmids pTiAch5 and pTi15955. Sequence analysis shows that the limited and wide host range biotype III OC TA regions are derived from a common ancestor structure which lacked the 6a gene found in the biotype I octopine TL region. The TA region of the wide host range OC Ti plasmids has conserved most of the original TL-like structure. In most wide host range OC isolates the TA-iaaH gene is inactivated by the insertion of an IS866 element. However, the TA region of the wide host range isolate Hm1 carries an intact TA-iaaH gene. This gene encodes a biologically active product, as shown by root induction tests and indole-3-acetic acid measurements. The limited host range OC Ti plasmids pTiAB3 and pTiAg57 have shorter TA regions which are derived from a wide host range TA region. The AB3 type arose by an IS868-mediated, internal TA region deletion which removed the iaa genes and part of the ipt gene and left a copy of IS868 at the position of the deleted fragment. The pTiAB3 iaa/ipt deletion was followed by insertion of a second IS element, IS869, immediately 3′ of the ipt gene. pTiAg57 underwent the same iaa-ipt deletion as pTiAB3, but lacks the IS868 and IS869 elements. Analysis of the various TA region structures provides a detailed insight into the evolution of the biotype III OC strains.
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  • 73
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    Plant molecular biology 16 (1991), S. 335-337 
    ISSN: 1573-5028
    Keywords: Triticum ; wheat ; endosperm ; gliadin ; pseudogene ; duplication ; evolution
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  • 74
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    Plant molecular biology 18 (1992), S. 777-780 
    ISSN: 1573-5028
    Keywords: Cyanidium caldarium ; evolution ; Galdieria sulphuraria ; rRNA operon
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  • 75
    ISSN: 1573-5028
    Keywords: calcium-binding protein ; centrin ; EF hand ; evolution ; green algae
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    Topics: Biology
    Notes: Abstract Centrin (= caltractin) is a ubiquitous, cytoskeletal protein which is a member of the EF-hand superfamily of calcium-binding proteins. A centrin-coding cDNA was isolated and characterized from the prasinophyte green alga Scherffelia dubia. Centrin PCR amplification primers were used to isolate partial, homologous cDNA sequences from the green algae Tetraselmis striata and Spermatozopsis similis. Annealing analyses suggested that centrin is a single-copy-coding region in T. striata and S. similis and other green algae studied. Centrin-coding regions from S. dubia, S. similis and T. striata encode four colinear EF-hand domains which putatively bind calcium. Phylogenetic analyses, including homologous sequences from Chlamydomonas reinhardtii and the land plant Atriplex nummularia, demonstrate that the domains of centrins are congruent and arose from the two-fold duplication of an ancestral EF hand with Domains 1+3 and Domains 2+4 clustering. The domains of centrins are also congruent with those of calmodulins demonstrating that, like calmodulin, centrin is an ancient protein which arose within the ancestor of all eukaryotes via gene duplication. Phylogenetic relationships inferred from centrin-coding region comparisons mirror results of small subunit ribosomal RNA sequence analyses suggesting that centrin-coding regions are useful evolutionary markers within the green algae.
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  • 76
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    Plant molecular biology 26 (1994), S. 1065-1071 
    ISSN: 1573-5028
    Keywords: Brassica ; polyploid ; gene expression ; RT-PCR ; RFLP
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    Topics: Biology
    Notes: Abstract One of the essential issues regarding evolution of polyploid species is how duplicate genes are expressed. Most studies on gene expression in polyploids have been based on isozyme analyses; RNA analysis has not been widely used partially due to difficulties in distinguishing homologous transcripts which usually have the same length and similar or almost identical sequences. In this study, a method combining RT-PCR with RFLP was used to analyze transcripts of homologous genes in natural and synthetic Brassica amphidiploids. Sequences coding for several known genes were selected and used to synthesize gene-specific primers. Total RNAs were used as templates for RT-PCR to amplify homologous transcripts in three diploid parental species, three cultivated amphidiploid species and six synthetic amphidiploids. For each gene, initial PCR products amplified in all species had identical length; however, homologous transcripts in the diploid and amphidiploid species could be distinguished after digesting the PCR products with restriction enzymes. Preliminary results based on three genes indicated that both transcripts from the diploid parents were expressed in the synthetic and natural amphidiploids. This study represents the first application of RT-PCR and RFLP analysis to investigate expression of homologous genes in higher plants. The technique is a sensitive, simple and efficient method for distinguishing homologous transcripts in a mixed RNA population and can be applied to many types of studies on expression of homologous genes.
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  • 77
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    Plant molecular biology 16 (1991), S. 831-839 
    ISSN: 1573-5028
    Keywords: RFLP ; Oryza ; rice ; genome evolution ; allotetraploid
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    Topics: Biology
    Notes: Abstract Restriction fragment length polymorphisms (RFLPs) were studied in fourteen accessions of CCDD genome allotetraploid wild rice species (Oryza latifolia, O. alta and O. grandiglumis). Fourteen nuclear RFLP markers previously mapped in AA genome-cultivated rice were used as probes. A phylogenetic tree, constructed by parsimony analysis based on RFLPs, grouped the accessions according to their geographic origin from Central or South America. Oryza alta, O. grandiglumis and one accession of O. latifolia grouped together as a subgroup, and our results suggested that the three taxa should be considered as populations of a single complex species. Duplicate loci, representing the two constituent genomes of the allotetraploid, were observed for most RFLP markers. By comparing RFLPs from the allotetraploids with those from a CC genome diploid wild species (O. officinalis), it was possible to detect RFLPs specific for both the CC and DD genomes of the allotetraploid. In inter-accession F2 populations, independent segregation of RFLP markers for CC and DD genomes was observed.
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  • 78
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    Plant molecular biology 16 (1991), S. 537-546 
    ISSN: 1573-5028
    Keywords: Antithamnion sp. ; chloroplast ; Cyanidium caldarium Geitler ; evolution ; red algae ; rRNA operon ; rRNA spacer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The nucleotide sequences of the plastid 16S rDNA of the multicellular red alga Antithamnion sp. and the 16S rDNA/23S rDNA intergenic spacers of the plastid DNAs of the unicellular red alga Cyanidium caldarium and of Antithamnion sp. were determined. Sequence comparisons support the idea of a polyphyletic origin of the red algal and the higher-plant chloroplasts. Both spacer regions include the unsplit tRNAIle (GAU) and tRNAAla (UGC) genes and so the plastids of both algae form a homogeneous group with those of chromophytic algae and Cyanophora paradoxa characterized by ‘small-sized’ rDNA spacers in contrast to green algae and higher plants. Nevertheless, remarkable sequence differences within the rRNA and the tRNA genes give the plastids of Cyanidium caldarium a rather isolated position.
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  • 79
    ISSN: 1573-5028
    Keywords: algae ; endosymbiosis ; evolution ; plastidial DNA ; Rubisco operon
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    Topics: Biology
    Notes: Abstract The rbcS gene coding for the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) of the brown alga Pylaiella littoralis is located within the plastid genome and is transcribed as a single polycistronic mRNA with the gene for the large subunit of Rubisco, rbcL. The structure of the Rubisco operon from P. littoralis was determined. Molecular phylogenies for rbcS and rbcL with a wide range of prokaryotes and eukaryotes were constructed which are congruent with recent evidence for polyphyletic plastid origins. Both rbcL and rbcS of the β-purple bacterium Alcaligenes eutrophus clearly cluster with the rhodophyte and chromophyte proteins. The data suggest that the Rubisco operons of red algal and chromophytic plastids derive from β-purple eubacterial antecedents, rather than the cyanobacterial lineage of eubacteria from which other of their genes derive. This implies a lateral transfer of Rubisco genes from β-purple eubacterial ancestors to the cyanobacterial ancestor of rhodophyte and chromophyte plastids.
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  • 80
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    Plant molecular biology 17 (1991), S. 641-652 
    ISSN: 1573-5028
    Keywords: F-ATPase ; cyanobacteria ; operon ; evolution ; photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The two operons atp1 and atp2, encoding the subunits of the FOF1 ATP-synthase, have been cloned and sequenced from the cyanobacterium Synechocystis sp. PCC 6803. The organization of the different genes in the operons have been found to resemble that of the cyanobacteria Synechococcus sp. PCC 6301 and Anabaena sp. PCC 7120. The Synechocystis FOF1 ATP-synthase has nine subunits. A tenth open reading frame with unknown function was detected at the 5′ end of atp1, coding for a putative gene product similar to uncI in Escherichia coli. A promoter structure was inferred for the Synechocystis atp operons and compared to other known promoters of cyanobacteria. Even though the operon structure of atp1 and atp2 in Synechocystis resembles the corresponding operons of Synechococcus, the amino acid sequences of individual gene products show marked differences. Genetic distances between cyanobacterial genes and genes for ATP-synthase subunits from other species have been calculated and compiled into evolutionary trees.
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  • 81
    ISSN: 1573-5028
    Keywords: chromosome assignment ; dihaploid progenies ; heterozygosity ; potato ; rDNA ; RFLP
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    Notes: Abstract Restriction map and organization of rDNA was inferred from analysis of dihaploid progenies of two tetraploid genotypes of cultivated potato. Each tetraploid genotype was characterized by a specific distribution of different types of rDNA repetition units on their four homologous chromosomesII. The genotypes were heterozygous and differed by the kind of units carried by each chromosomeII. Models for the generation of the observed organization are discussed and supported by first cloning studies.
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    Molecular biology reports 20 (1994), S. 1-8 
    ISSN: 1573-4978
    Keywords: review ; zinc finger protein ; DNA recognition ; evolution ; development
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    Topics: Biology
    Notes: Abstract Complexity is one of the hallmarks that applies to C2H2 type zinc finger proteins (ZFPs). Structurally distinct clusters of zinc finger modules define an extremely large superfamily of nucleic acid binding proteins with several hundred, perhaps thousands of different members in vertebrates. Recent discoveries have provided new insights into the biochemistry of RNA and DNA recognition, into ZFP evolution and genomic organization, and also into basic aspects of their biological function. However, as much as we have learned, other fundamental questions about ZFP function remain highly enigmatic. This essay is meant to define what we personally feel are important questions, rather than trying to provide a comprehensive, encyclopaedic review.
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  • 83
    ISSN: 1573-5028
    Keywords: cDNA ; cyanogenesis ; β-glucosidase ; RFLP ; Trifolium repens
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    Topics: Biology
    Notes: Abstract The Li locus in white clover controls the presence of cyanogenic β-glucosidase (linamarase) activity in leaf tissue, such that plants homozygous for the ‘null’ allele (li) have no linamarase activity in this tissue. The isolation of a cDNA clone from linamarase mRNA is described. The cDNA clone is used to further characterise alleles of the Li locus. Northern blot analysis shows that plants homozygous for the ‘null’ allele (li li) produce very reduced levels of mRNA which hybridises to the cDNA. Heterozygous plants (Li li), which have intermediate levels of enzyme activity, produce intermediate levels of mRNA. Southern blot analysis of Hind III digested genomic DNA shows that the white clover genome contains three genes with homology to the linamarase cDNA and that at least two of these genes segregate independently. Analysis of the cosegregation of linamarase activity and the presence of genomic restriction fragments identifies the genomic sequence specifying linamarase structure and indicates either a structural or cis acting control function of the Li locus.
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  • 84
    ISSN: 1573-5028
    Keywords: Rubisco activase ; rca ; rbcLrbcS ; cyanobacteria ; expression ; evolution
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    Topics: Biology
    Notes: Abstract A gene encoding ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) activase (rca) was found downstream from the rbcLrbcS operon in the heterocystous cyanobacterium Anabaena sp. strain CA. Two unknown open reading frames were shown to be located between rbcS and rca in strain CA and all the genes, rbcLrbcS, ORF1, ORF2, and rca were in the same transcriptional orientation. The deduced amino acid sequence of the Anabaena Rubisco activase showed both similarities and differences to the plant enzyme with considerable differences at the carboxy and amino termini. Proposed ATP-binding sites were conserved in the cyanobacterial protein. Recombinant cyanobacterial Rubisco activase, however, reacted with antisera to spinach Rubisco activase. Hybridization studies, using the Anabaena sp. strain CA rca gene as a heterologous probe, detected homologous sequences in heterocystous Anabaena/Nostoc strains but not in unicellular or nonheterocystous filamentous cyanobacteria, suggestive of a close evolutionary relationship of chloroplasts and heterocystous cyanobacteria.
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    Plant molecular biology 22 (1993), S. 437-446 
    ISSN: 1573-5028
    Keywords: RFLP ; genome ; PFGE ; multicopy markers ; symbiosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Pulsed-field gel electrophoresis (PFGE) was used to study a cluster of molecular markers in the soybean genome. There were 550 kb per centimorgan (cM) in the cluster, which is close to the calculated average for the whole genome. The analysis was complicated by the presence of duplicated sequences, and some ambiguities arising from this were resolved by using second-dimension conventional electrophoresis to relate physical maps to the RFLP map of soybean. The results show that there is a high degree of conservation of ‘rare cutter’ sites between homoeologous regions. Finally, PFGE can confirm physical linkage of monomorphic copies of markers, which can aid in the study and comparison of homoeologous regions that are invisible to RFLP analysis.
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  • 86
    ISSN: 1573-5028
    Keywords: chloroplast ; evolution ; red algae ; thioredoxin
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    Topics: Biology
    Notes: Abstract A gene encoding a thioredoxin protein was identified in the chloroplast genome of the rhodophyte Porphyra yezoensis. The P. yezoensis trxA gene contains 324 bp and is transcribed into a 0.7 kb messenger RNA. Analysis of the transcription start site demonstrates that canonical chloroplast −10 and −35 sequences are not present. The deduced amino acid sequence of the thioredoxin gene from the red algae has the greatest similarity to type m thioredoxins, providing strong support for the hypothesis that type m thioredoxins in photosynthetic eukaryotes originated from an engulfed bacterial endosymbiont. Hybridization analysis of nuclear and chloroplast DNAs from several members of the phyla Chromophyta and Rhodophyta using P. yezoensis DNA as a probe demonstrated strong hybridization to the chloroplast and nuclear genomes of Griffithsia pacifica and a weak cross-hybridization to the chromophyte P. foliaceum. The G. pacifica chloroplast gene has a 66% identity with the P. yezoensis DNA, contains conserved active site amino acid residues, but lacks a methionine start codon.
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    Theoretical and applied genetics 79 (1990), S. 577-582 
    ISSN: 1432-2242
    Keywords: Genetic marker ; RFLP ; Quantitative traits
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Digestion of genomic DNA with the restriction endonuclease Avail disclosed a probable insertion deletion of approximately 200 base pairs (bp) near the prolactin gene. Two alleles were apparent as three distinct hybridization patterns. These alleles were statistically associated with quantitative trait loci among sons of one elite Holstein sire family. The favorable genotype was correlated with the presence of a 1.15-kb hybridization band inherited from the sire when genomic DNA was probed with a full-length cDNA for prolactin. Pedigree estimates of genetic merit among genotypes were similar, differing by only 19.3 kg for milk in ancestor merit. Comparisons of genetic estimates for quantitative yield traits in offspring of this heterozygous sire showed significant (P〈0.05) differences between homozygous genotypes for predicted difference milk (PDM), predicted difference dollars (PD$), cheese yield dollars, and protein dollars. The estimated differences between homozygous genotypes for USDA Transmitting Abilities of PDM, PD$, Cheese Yield $ and Protein $ were 282.93 kg, $74.35, $48.58 and $53.67, respectively. However, the estimated breeding values from progeny ranged over 900 kg in transmitting ability for milk. Frequency of the favorable marker allele was estimated to be 0.231 in the elite cow population used as dams of sons. These results demonstrate the potential of molecular biological techniques to discriminate between individuals within a family and to predict breeding values for selection schemes.
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    Theoretical and applied genetics 80 (1990), S. 673-679 
    ISSN: 1432-2242
    Keywords: Rice ; Tissue culture ; Somaclonal variation ; RFLP ; Methylation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Regenerants of rice were examined by RFLP analysis to determine the occurrence and extent of somaclonal variation. DNA polymorphisms were observed both among plants regenerated from different callus cultures as well as among sibling plants derived from a single callus. Regardless of the basal medium, a higher degree of genetic instability was found among plants regenerated from callus cultures maintained for longer incubation periods (67 days) than among those from shorter incubation periods (28 days). Detailed analysis showed that in several regenerants, there was a close correlation among those plants exhibiting DNA rearrangements and those with apparent methylation changes. Such alterations were observed with both structural and housekeeping genes.
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    Theoretical and applied genetics 80 (1990), S. 680-686 
    ISSN: 1432-2242
    Keywords: Retrotransposon ; Zea ; RFLP ; Bs1 ; Transposable element
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Thirty-eight accessions from Zea and 20 accessions from related genera were probed for the presence of Bs1, a retrotransposon originally found in maize. All maize and teosinte plants tested show the presence of Bs1 in one to five densely hybridizing bands. The mean copy numbers of Bs1 elements among the maize and teosinte accessions were similar: 2.92 and 3.25, respectively, with no large differences between any subgroups. Most exotic maize samples exhibited two common bands of 7.8 kb and 4.7 kb. Section Zea teosintes (but not teosintes of section Luxuriantes) also show the presence of a common band of the same size as the smaller common band in maize. At reduced stringency, Tripsacum dactyloides exhibited a single hybridizing band at 6.9 kb. Results argue for the evolution of maize from a mexicana or parviglumis teosinte, and the evolution of the Bs1 element within the tribe Andropogoneae. Additionally, recombinant inbred lines were probed for the presence of Bs1, in order to map the chromosomal locations of Bs1 elements in four different maize lines. Two of the recombinant inbred parental lines had an element (Bs1-F) on chromosome 5, while the other two lines had an element (Bs1-S) on chromosome 8. Restriction site polymorphisms have apparently arisen in the vicinity of Bs1-S since its insertion. Segregation analysis of other lines was also performed; the data indicate that Bs1 has the distribution expected of a transposable element, different locations in different lines, and not that of a fixed gene locus. However, the common bands in the Zea mays lines and the recombinant inbred data imply that Bs1 is not highly mobile.
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    Theoretical and applied genetics 82 (1991), S. 393-398 
    ISSN: 1432-2242
    Keywords: Maize ; Helminthosporium turcicum race1 ; RFLP ; NILs ; Mapping
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have identified tight linkage of an RFLP marker to theHt1 gene of maize that confers resistance to the fungal pathogenHelminthosporium turcicum race 1. This was accomplished by the use of four pairs of near isogenic lines (NILs; B73, A619, W153R, and CM105), each differing by the presence or the absence of the geneHt1. SinceHt1 maps to chromosome 2, 26 clones already mapped to this chromosome were labeled and probed against Southern blots of these NILs DNA digested with three restriction enzymes:EcoRI,BamHI, andHindIII. Six markers exhibited an RFLP for at least one pair of NILs. Presumptive linkage was further tested by analyzing the segregation of five of the six markers (one was monomorphic in the cross studied) and resistance toH. turcicum race 1 on 95 F2 individuals from the cross DF20 × LH146Ht. The results indicate a tight linkage between one of the DNA markers,UMC150B, and theHt1 gene.
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    Theoretical and applied genetics 82 (1991), S. 697-703 
    ISSN: 1432-2242
    Keywords: RFLP ; Bamboo ; Phyllostachys ; Chloroplast DNA ; Germplasm screening
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Bamboo species are difficult to identify because flowering material is seldom available and taxonomy is of necessity based on vegetative characters. To evaluate the utility of restriction fragment length polymorphism (RFLP) analysis in bamboo systematics and germplasm screening, a library of random genomic probes from a Phyllostachys nigra PstI library was constructed. Probes from the library were used to screen bamboo germplasm consisting mostly of temperate bamboos of the genus Phyllostachys. RFLP variation was abundant, and species-specific patterns were readily obtained. Chloroplast DNA showed little variation among the bamboo accessions analyzed.
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  • 92
    ISSN: 1432-2242
    Keywords: RFLP ; PCR ; Rice ; Inheritance ; Nonradioactive
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Thirty mapped Indica rice genomic (RG) clones were partially sequenced from each end. From such sequence data, pairs of oligonucleotides were synthesized to act as primers for polymerase chain reaction (PCR) amplification of the corresponding loci in crude total DNA preparations. The PCR products from DNA of Indica varieties were of the sizes expected from the sizes of the corresponding RG clones. However, size polymorphisms were seen between PCR products from Indica and Japonica varieties, and among wildOryza species. Restriction fragment length polymorphism (RFLP) was observed between PCR products of Indica varieties simply by electrophoretic analysis of restricted products, without the need for Southern hybridization or radiolabelling. The RFLPs noted between varieties ARC6650 and Phalguna were inherited in recombinant inbred lines derived from a cross between them. The RFLPs were detectable in PCR products amplified from DNA extracted by a simple procedure from single seedlings or leaves, and revealed genetic heterogeneity in cultivated lines. An approach is described that is relevant to the acceleration of classical plant breeding through molecular techniques.
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  • 93
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    Theoretical and applied genetics 83 (1991), S. 89-96 
    ISSN: 1432-2242
    Keywords: RFLP ; Alfalfa ; Genetic diversity ; Phylogenetic tree ; Gene duplication
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Alfalfa (Medicago sativa L.) is a major forage crop throughout the world. Although alfalfa has many desirable traits, continued breeding is required to incorporate pest resistances and other traits. We conducted this study to determine the amount of restriction fragment length polymorphism (RFLP) variability present within and between diploid and tetraploid alfalfa populations, and whether or not this variability is sufficient for construction of an RFLP map. Diploid plants from M. sativa ssp. falcata, ssp. coerulea, and ssp. sativa and tetraploid spp. sativa cultivars ‘Apollo,’ ‘Florida 77,’ and ‘Spredor 2’ were included. A total of 19 cDNA clones was probed onto genomic Southern blots containing DNA digested by EcoRI, HindIII, or BamHI. Phylogenetic trees were produced, based on parsimony analysis of shared restriction fragments. Evidence for extensive gene duplication was found; most probes detected complex patterns of restriction fragments. Large amounts of variation are present within all diploid subspecies. M. sativa ssp. falcata plants formed clusters distinct from ssp. sativa or ssp. coerulea plants, which were not distinctly clustered. Some M. sativa ssp. falcata plants were more similar to the other groups than to other plants within ssp. falcata. Variation among tetraploid cultivars showed that Florida 77 and Apollo had more similarities than either showed with Spredor 2. All three cultivars showed large within-population variation, with Apollo being the most diverse and Spredor 2 the least. Based on these results, development of an RFLP map at the diploid level appears possible. Also, differentiation of cultivars, particularly ones of divergent origin, seems possible based on RFLP patterns.
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    Theoretical and applied genetics 83 (1992), S. 428-434 
    ISSN: 1432-2242
    Keywords: ‘Null’ forms ; RFLP ; Gliadins ; LMW glutenins ; Deletion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Wheat accessions lacking some of the ω- and γ-gliadin components encoded by the Gli-1 loci on the short arm of chromosome 1D in bread wheat and chromosome 1A in durum wheat were studied by two-dimensional polyacrylamide gel electrophoresis and restriction fragment analysis. Digested genomic DNAs of ‘normal’ and ‘null’ forms were probed with a cDNA clone related to ω-/γ-gliadins and with a genomic clone encoding an LMW subunit of glutenin. The hybridisation patterns with the ω-/γ-gliadin probe were similar to those of cvs ‘Chinese Spring’ and ‘Langdon’ used as standards for bread and durum wheats, respectively, but several restriction fragments located on the 1D chromosome of bread wheat and the 1A chromosome of durum wheat were absent in the ‘null’ forms. In addition, specific LMW glutenin fragments encoded by the same chromosomes were also absent in the ‘null’ forms, suggesting that simultaneous deletions of blocks of genes for both ω-/γ-gliadins and LMW glutenins had occurred. Comparisons of the protein and RFLP patterns enabled some proteins to be mapped to specific restriction fragments.
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  • 95
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    Theoretical and applied genetics 83 (1992), S. 895-902 
    ISSN: 1432-2242
    Keywords: Finger millet ; Eleusine ; rDNA ; RFLP ; Grasses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Finger millet is an important cereal crop in the semi-arid regions of Africa and India. The crop belongs to the grass genus Eleusine, which includes nine annual and perennial species native to Africa except for the New World species E. tristachya. Ribosomal DNA (rDNA) variation in finger millet and related wild species was used to provide information on the origin of the genomes of this tetraploid crop and point out genetic relationships of the crop to other species in the genus. The restriction endonucleases used revealed a lack of variability in the rDNA spacer region in domesticated finger millet. All the rDNA variants of the crop were found in the proposed direct tetraploid ancestor, E. coracana subsp. africana. Wild and domesticated finger millet displayed the phenotypes found in diploid E. indica. Diploid Eleusine tristachya showed some similarity to the crop in some restriction sites. The remaining species were quite distinct in rDNA fragment patterns. The study supports the direct origin of finger millet from subspecies africana shows E. indica to be one of the genome donors of the crop, and demonstrates that none of the other species examined could have donated the second genome of the crop. The rDNA data raise the possibility that wild and domesticated finger millet could have originated as infraspecific polyploid hybrids from different varieties of E. indica.
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  • 96
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    Theoretical and applied genetics 84 (1992), S. 39-48 
    ISSN: 1432-2242
    Keywords: Genetic map ; Molecular markers ; RFLP ; Fruit breeding ; Citrus spp.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Genetic linkage analysis was performed using two segregating populations of citrus. One population arose from an intergeneric backcross of Citrus grandis (L.) Osb. cv ‘Thong Dee’ and Poncirus trifoliata (L.) Raf. cv ‘Pomeroy’, using the former as the recurrent (female) parent. The other population came from an interspecific backcross of C. reticulata Blanco cv ‘Clementine’ and C. x paradisi Macf. cv ‘Duncan’, using the former as the recurrent (male) parent. A total of 11 isozyme and 58 restriction fragment length polymorphisms were found to segregate in a monogenic fashion in one or both populations. Linkage analysis revealed that 62 of the loci examined mapped to 11 linkage groups, while 7 loci segregated independently from all other markers. Gene order was highly conserved between the maps generated from the two divergent segregating populations. Possible applications of the use of such maps in tree fruit breeding are discussed.
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  • 97
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    Theoretical and applied genetics 84 (1992), S. 113-117 
    ISSN: 1432-2242
    Keywords: Beet ; Somaclonal variation ; Isozyme ; RFLP ; Genetic stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Sugar, fodder and garden beet (Beta vulgaris L.) plants have been regenerated in culture from a range of expiant material. Of the regenerants 764 were subjected to isozyme analysis using eight enzyme-specific stains, and 60 were subjected to RFLP analysis using three cDNA probes. Both molecular techniques allowed the identification of somaclonal variant plants. Assessment of the numbers of variant isozymes and restriction fragments has allowed the calculation of the approximate percentage of variant alleles occurring in any one somaclonal regenerant, namely between 0.05% and 0.1%.
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    Theoretical and applied genetics 84 (1992), S. 286-290 
    ISSN: 1432-2242
    Keywords: Taxonomy ; Banana ; RFLP ; Musa ; Phylogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Random genomic probes were used to detect RFLPs in 19 Musa species and subspecies. A total of 89 phylogenetically informative alleles were scored and analyzed cladistically and phenetically. Results were in general agreement with morphology-based phylogenetic analyses, with the following exceptions: our data unambiguously places M. boman in section Australimusa, and indicates M. beccarii is very closely related to M. acuminata. Additionally, no support was found for the separation of section Rhodochlamys from section Musa. A comparison of morphology-based and RFLP-based phylogenetic analyses is presented.
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    Theoretical and applied genetics 84 (1992), S. 845-850 
    ISSN: 1432-2242
    Keywords: Flax ; Rust ; RFLP ; Genetic segregation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Random cDNA sequences synthesized from poly A+ RNA extracted from germinated urediospores of the flax rust fungus, Melampsora lini, were used as probes to detect restriction fragment length polymorphisms (RFLPs) in three races of M. lini originating from cultivated flax, Linum usitatissimum, and one race originating from Australian native flax, L. marginale. Fourteen out of 22 probes tested detected RFLPs in the three races from cultivated flax while 19 of the probes detected polymorphisms between these three races and the race from L. marginale. The segregation of seven RFLPs was determined in a family of 19 F2 progeny derived from a cross between two of the rust races. With six of these the inheritance was consistent, in each case, with the segregation of alleles at a single locus. Inheritance of the seventh was unusual and an explanation involving two loci with null alleles at each was proposed. No linkage was detected between any of the RFLP loci and nine unlinked loci specifying avirulence.
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  • 100
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    Theoretical and applied genetics 85 (1992), S. 101-104 
    ISSN: 1432-2242
    Keywords: Marker assisted selection ; RFLP ; QTL ; Quantitative genetics ; Corn breeding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The objective of this paper is to present genetic theory demonstrating the conditions under which it should be possible to identify molecular marker-quantitative trait locus (QTL) associations in crosses of random-mating populations to inbreds. Using as an example the cross of a corn (Zea mays L.) population to an inbred, the expected disequilibrium for testcross and per se performance of F2, F3, BC1 (to the inbred) and recombinant inbred generations was derived for cases where a marker allele is linked to an unfavorable QTL allele in the inbred and where the marker allele is linked to a favorable QTL allele in the inbred. Disequilibrium in segregating generations was shown to be a function of disequilibrium in the parent population, the frequency of marker and QTL alleles in the parent population, and the recombination distance between the marker and the QTL. To maximize the opportunity to identify a favorable QTL the following procedures are suggested: (1) Select marker loci with alleles in the parent population which are not present in the inbred. (2) Select populations known to have favorable QTL alleles not present in the inbred. (3) Use as many marker loci as possible to enhance the probability of tight linkage between the marker and the QTL.
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