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  • Drosophila  (22)
  • Springer  (22)
  • Blackwell Publishing Ltd
  • American Institute of Physics (AIP)
  • 1980-1984  (22)
  • 1980  (22)
Sammlung
Schlagwörter
Verlag/Herausgeber
  • Springer  (22)
  • Blackwell Publishing Ltd
  • American Institute of Physics (AIP)
  • Wiley-Blackwell  (1)
Erscheinungszeitraum
  • 1980-1984  (22)
Jahr
  • 1
    Digitale Medien
    Digitale Medien
    Adaptation ofDrosophila enzymes to temperature. III. Evolutionary conservatism in mitochondrial enzymes (1980)
    Springer
    Journal of molecular evolution 16 (1980), S. 37-46 
    Details
    ISSN: 1432-1432
    Schlagwort(e): Evolution ; Drosophila ; Temperature ; Mitochondrial enzymes ; Kinetic properties
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The evolutionary behavior of two mitochondrial enzymes (L-glycerol 3-phosphate:cytochrome c oxidoreductase E.C.1.1.1.95,αGPO, and L-malate: NAD+ oxidoreductase, E.C.1.1.1.37, m-MDH) obtained from several temperate and tropicalDrosophila species was examined by comparing their catalytic properties, which related to temperature (Km-Ea-Q10-Thermostability). MitochondrialαGPO or m-MDH obtained either from temperate or from tropical species was found to exhibit similar catalytic properties while for both cytosolic enzymes, theαGPDH and s-MDH, Km patterns were similar among species from the same thermal habitat and different between thermal habitats. In combination with other observations reported in the literature these facts support the view that the function, and probably the structure, of mitochondrial enzymes are better conserved in evolution than those of the corresponding enzymes found in the cytosol. It is proposed that the relative invariance of the mitochondrial enzymes structure is probably linked to a necessary relative invariance of molecular interactions inside the mitochondrion.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01732068
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  • 2
    Digitale Medien
    Digitale Medien
    The effect of temperature onshibire ts cell clones in the compound eye ofDrosophila melanogaster (1980)
    Springer
    Development genes and evolution 188 (1980), S. 55-63 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Compound eye ; shibire ts ; Development
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary We have analysed the effect of temperature on both developing and adult eye cell clones homozygous forshi ST139, a temperature-sensitive mutant ofDrosophila melanogaster. The mutant gene, autonomous in its cellular expression, causes structural modifications of ommatidial cells when adult clones of cells are exposed to the restrictive temperature (29°C) for several days. However, the mutant phenotype reverses to normal within 4 days at the permissive temperature (20°C). The results of pulse, shift-up and shift-down experiments show that the temperaturesensitive period for developing compound eye cells is from the late second instar up to the early pupa. Cytodifferentiation of compound eye cells is blocked by restrictive temperature treatment during this period, whereas cell proliferation does not seem to be directly affected. These results are discussed with regard to the other known aspects of the phenotype observed in mutant individuals.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848610
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  • 3
    Digitale Medien
    Digitale Medien
    Morphogenesis in the embryo ofDrosophila melanogaster — Germ band extension (1980)
    Springer
    Development genes and evolution 188 (1980), S. 163-177 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Yolk sac ; Ultrastructure ; Embryogenesis ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Changes at the ultrastructural level during germ band extension in the embryo ofDrosophila melanogaster are described. Cytoplasmic connections between cells and the yolk sac are present during initial cellular movements. At this time, a continuous system of microfilaments is present adjacent to the membranes in the connections and at the periphery of the yolk sac. As germ band extension progresses, this system becomes discontinuous, and microfilaments are apparent only in the immediate vicinity of the connections. Cytoplasmic connections are disassembled at approximately the midpoint of extension; at the same time, extensive membrane associations develop between germ band cells and between these cells and adjacent yolk sac membranes. Positioning and orientation of cytoplasmic connections suggest that the yolk sac, via these connections, is actively involved in the cellular movements of early germ band extension.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00849045
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  • 4
    Digitale Medien
    Digitale Medien
    Developmental studies on two ecdysone deficient mutants ofDrosophila melanogaster (1980)
    Springer
    Development genes and evolution 189 (1980), S. 57-67 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Ecdysone deficient mutants ; Ecdysteroid titer ; Ring gland ; Fine structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary This paper describes two ecdysone-deficient, recessive-lethal mutants,lethal(1)giant ring gland (grg) andlethal(1)suppressor of forked mad-ts (mad-ts: Jürgens and Gateff 1979) and compares their ecdysteroid titers with that of the wild-type. Mutant larvae show a much reduced ecdysteroid content, amounting to 1/10 to 1/30 of the wild-type values, but never a true titer peak. They fail to pupate and die after 1–3 weeks. Ecdysteroid feeding elicits different responses in the larvae of the two mutants.mad-ts larvae pupate within 24 h, thus showing that their low ecdysteroid titer is directly connected to their inability to pupate.mad-ts resembles the mutantlethal (3)ecdysone-1 ts (Garen et al. 1977). Thegrg mutant larvae, on the other hand, fail to pupate after 20-hydroxyecdysone feeding as well as injection. The primary defect of thegrg mutant is not entirely clear. Thegrg larval salivary gland cells appear to possess normal ecdysteroid receptors. Furthermore, the low ecdysteroid titer ingrg is not the result of an increased ecdysteroid catabolism. The primary defect in the mutant may lie in the malfunctioning neurosecretory cells which do not show neurosecretion in histological preparations. Further support for this notion comes from electronmicrographs of the enlargedgrg ring glands which, in contrast to the wild-type, do not possess nerve endings. In the wild-type three ecdysteroid peaks were found: one shortly before puparium formation, the second at approximately 12 h and the third at about 30 h after pupation. The ecdysteroid titer peak in late third instar, wild-type larvae is mainly due to the presence of 20-dydroxyecdysone as shown by radioimmunoassays after thin layer chromatography and derivatization followed by gas liquid chromatography and mass spectroscopy. In addition, a number of unidentified polar and apolar metabolites were also present.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848567
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  • 5
    Digitale Medien
    Digitale Medien
    Compartments and distal outgrowth in theDrosophila imaginal wing disc (1980)
    Springer
    Development genes and evolution 188 (1980), S. 157-161 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Imaginal discs ; Compartments ; Distal outgrowth
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Peripheral tissue of the imaginal wing disc gives rise to the proximal mesothoracic structures of the adult. Pieces of peripheral tissue, which have no regenerative capacity when cultured as intact fragments, are capable of distal outgrowth (regeneration) after dissociation and reaggregation. This ability depends on the region of the disc periphery from which the fragment is taken. Extensive distal outgrowth occurs in reaggreages of a fragment containing equal proportions of tissue from anterior and posterior developmental compartments. The extent of outgrowth decreases as the proportion of posterior tissue is reduced, so that a fragment containing only anterior tissue shows no regeneration after dissociation. Limited distal outgrowth occurs in reaggregates of a wholly posterior fragment, but the regenerative capacity is increased greatly when a small amount of anterior tissue is included. It is concluded that distal outgrowth in the wing disc requires an interaction between cells of the anterior and posterior compartments.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848808
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  • 6
    Digitale Medien
    Digitale Medien
    Is regeneration inDrosophila the result of epimorphic regulation? (1980)
    Springer
    Development genes and evolution 189 (1980), S. 91-96 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Epimorphic regulation ; Drosophila ; Imaginal discs
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary It has been known for many years that when a wing disc ofDrosophila is bisected, and the fragments cultured in adult females, regulation occurs and either a complete disc is regenerated or the fragment is duplicated. We have investigated how this regeneration process occurs. To establish which cells contribute to the regenerate, and thus determine if regeneration is the result of epimorphic regulation, fragments of discs, after culture in an adult for one to five days, were exposed to3H-thymidine to label replicating cells. Imaginal discs, both whole and as regenerating fragments, undergo some DNA replication which is distributed throughout the disc, but cut discs frequently show clusters of labelled cells around the wound, indicating that regeneration is probably epimorphic.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848497
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  • 7
    Digitale Medien
    Digitale Medien
    Embryogenesis inDrosophila: Can a single mechanism explain the developmental segregation of germ-line and somatic cells and their subsequent determination? (1980)
    Springer
    Development genes and evolution 188 (1980), S. 179-185 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Determination ; Germ-line ; Somatic cells ; Inhibitor gradient hypothesis ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary A hypothesis is presented which explains the segregation of germ cells from somatic cells, and the subsequent determination of both cell types with a single mechanism. This hypothesis is in part based on that of Meinhardt (1977) and can be summarized as follows: In the newly fertilized egg, the action of a sink in the pole plasm leads to the formation of an anterior-posterior gradient of an inhibitor. The concentration of this inhibitor in the posterior 20% of the egg is below that needed to repress synthesis of an activator. When, during the nuclear division stage, nuclei enter this posterior region, synthesis of the activator begins. As the activator is autocatalytic, this leads to the formation of a peak of activator in this region; and since the activator also catalyses the synthesis of the inhibitor, a peak of inhibitor is formed in the same place. The inhibitor then diffuses anteriorly through the periplasm, forming a posterior-anterior gradient. The presence of this inhibitor in the periplasm causes the nuclei that enter the periplasm to form blastoderm cells and to take up particular segmental states appropriate to their position, while those that remain in the yolk-containing plasm develop into vitellophages. The action of the sink in the pole plasm is postulated to result in the formation of the pole cells, and subsequently to direct some of these into forming cells of the germ-line.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00849046
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  • 8
    Digitale Medien
    Digitale Medien
    The morphological response of Kc-H cells to ecdysteroids: Hormonal specificity (1980)
    Springer
    Development genes and evolution 189 (1980), S. 1-15 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Cell line ; Drosophila ; Ecdysone ; Ecdysterone ; Hormones
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Cells of the line Kc, derived fromDrosophila melanogaster embryos, extend long processes when exposed to ecdysteroid hormones. We have devised a quantitative assay for this morphological response, using the subline Kc-H. The assay was used to characterize the conditions required for the response. A halfmaximal response is elicited by approximately 10−8M 20-hydroxyecdysone; the response is saturated by 10−7M 20-hydroxyecdysone, which causes detectable elongation within a few hours, and a maximal response after 2–3 days. The response occurs substantially normally in the absence of serum, during growth in suspension, and in over-crowded cultures. It is not elicited by cyclic nucleotides, vertebrate growth factors, or a variety of other non-ecdysteroid reagents. Of 60 ecdysteroid compounds tested, only those which were active in other insect test systems elicited the response, and the concentrations required were approximately proportional to the concentrations active in other in vitro systems. We conclude that the response of Kc cells to 20-hydroxyecdysone retains basic features of the ecdysteroid response of intact tissues and therefore that Kc cells are a useful model system for studying ecdysteroid action.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848562
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  • 9
    Digitale Medien
    Digitale Medien
    Crosslinking of theDrosophila chorion involves a peroxidase (1980)
    Springer
    Development genes and evolution 189 (1980), S. 187-196 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Eggshell ; Chorion ; Peroxidase ; Crosslinking ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary TheDrosophila chorion contains an endogenous peroxidase activity which remains inactive until late stage 14 when it catalyzes the crosslinking of the chorionic proteins. Using explanted follicles developing in vitro, premature, but otherwise normal crosslinking can be induced with hydrogen peroxide and normal crosslinking can be prevented with peroxidase inhibitors. Inhibition or premature activation of the shell peroxidase allows characterization of chorionic filament specific proteins and establishes new criteria for the identification of eggshell components.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00868677
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  • 10
    Digitale Medien
    Digitale Medien
    Expression of the zygotic genome in blastoderm stage embryos ofDrosophila: Analysis of a specific protein (1980)
    Springer
    Development genes and evolution 188 (1980), S. 153-156 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Embryogenesis ; mat (3) 1 mutation ; Two-dimensional gels
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The synthesis of a protein which has been detected in blastoderm cells but not in pole cells (Gutzeit and Gehring 1979) has been studied further by means of two-dimensional gel electrophoresis. This protein could not be detected at the nuclear multiplication stage. The protein is translated from mRNA which is transcribed at the blastoderm stage since it is not synthesized in detectable amounts when embryos are injected with α-amanitin prior to the blastoderm stage. Also the protein could not be detected when RNA from freshly laid eggs was translated in vitro. Embryos from females which are homozygous for the mutationmat (3) 1 form pole cells but no blastoderm cells (Rice and Garen 1975). Thesemat (3) 1 embryos, as we will call them in this report, express the protein if aged for a period of time sufficient for completion of blastoderm cell formation in control wild-type embryos.mat (3) 1 embryos and embryos injected with α-amanitin show the same syndrome of visible developmental anomalies; however, the studied protein could only be detected inmat (3) 1 embryos but not in α-amanitin injected embryos.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848807
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  • 11
    Digitale Medien
    Digitale Medien
    Characterization by isoelectric focusing of chorion protein variants inDrosophila melanogaster and their use in developmental and linkage analysis (1980)
    Springer
    Development genes and evolution 189 (1980), S. 17-24 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Geographic strains ; Chorion proteins ; Electrophoretic variants ; Chorion gene linkage
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Drosophila melanogaster chorion proteins are characterized on one-dimensional isoelectric focusing (IF) gels. The six major chorion components previously identified on SDS gels are shown to resolve into at least 11 components in our IF system. IF screening of 102 geographic strains ofDrosophila melanogaster revealed seven cases of variation in major chorion components. Two strains, Crimea and Falsterbo, which were monomorphic for a variant B1 protein and two strains, Skafto and Lausanne, which were monomorphic for a variant C1 protein, were chosen for further study. After IF developmental analysis of F1 hybrids had indicated that the sources of the variation resided in the structural genes for these proteins, each variant was crossed to a multiply marked and inverted strain (BLT) to determine the linkage group of the variant gene. To localize genes to more specific sites multiply marked 3rd (SKERO) or X-chromosomal (CB1) (X-PLE) mapping strains were used. In both Crimea and Falsterbo the gene for the B1 protein is located near map location 26 on the 3rd chromosome. In both Lausanne and Skafto the C1 gene is located on the X chromosome. Hence, for the first time, we have demonstrated genetically the non-linkage of two chorion genes, B1 and C1.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848563
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  • 12
    Digitale Medien
    Digitale Medien
    Timing and heritability of theNasobemia transformation inDrosophila (1980)
    Springer
    Development genes and evolution 189 (1980), S. 147-153 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Homeotic mutant ; Drosophila ; Clonal analysis ; Timing of gene action ; Determination
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Nasobemia (Ns) is a dominant homeotic mutant ofDrosophila melanogaster which converts parts or all of the antenna to mesothoracic leg.Ns has a temperature sensitive period between 48 and 60 h. The hypothesis thatNs acts during this period and is not required thereafter to maintain the homeotic transformation to leg was tested by removingNs fromNs/+ cells at different stages of development through X-ray induced somatic recombination. The expression of theNs homeotic transformation in recombinant wild type (+/+) cells increased sharply between 48 and 65 h. In clones induced after 65 h the expression of the leg transformation was equal in large and small +/+ clones. We interpret these results as supporting the hypothesis that transient action ofNs between 48 and 65 h switches antennal cells to a clonally stable leg determined state whose maintenance does not require futherNs action.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848503
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  • 13
    Digitale Medien
    Digitale Medien
    Functional significance of amylase polymorphism in Drosophila melanogaster. III. Ontogeny of amylase and some α-glucosidases (1980)
    Springer
    Biochemical genetics 18 (1980), S. 51-63 
    Details
    ISSN: 1573-4927
    Schlagwort(e): Drosophila ; ontogeny ; amylase ; α-glucosidases ; functional significance
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Changes in amylase (E.C. 3.2.1.1), maltase (E.C. 3.2.1.20), sucrase, and PNPGase activities in relation to changes in wet weight and protein content were studied during the development of larvae and adult flies from two strains of Drosophila melanogaster, homozygous for different amylase alleles. All α-glucosidase activities increase exponentially during a large part of larval development, parallel to the increase in weight, and drop at the end of the third instar. Amylase activity of the Amy 1 strain follows the same pattern. In contrast, amylase activity of the Amy 4,6 strain continues its exponential increase longer. In the third larval instar amylase activity in the Amy 4,6 strain becomes much higher than in the Amy 1 strain. During the first hours of adult life amylase activity of the two strains does not differ. Then Amy 4,6 activity starts to rise and becomes much higher (4–5 times) than Amy 1 amylase activity, which remains approximately constant. All adult enzyme activities are much higher than in larvae. Comparison of enzyme activity of amylase and α-glucosidases in larvae and adults confirms that differences in amylase activities can become important only when starch is a limiting factor in the food.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00504359
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  • 14
    Digitale Medien
    Digitale Medien
    Variation in Drosophila acetylcholinesterase (1980)
    Springer
    Biochemical genetics 18 (1980), S. 439-454 
    Details
    ISSN: 1573-4927
    Schlagwort(e): Drosophila ; acetylcholinesterase ; insecticide resistance ; electrophoretic variation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract We examined the Canton-S strain of Drosophila melanogaster for electrophoretic variation of the enzyme acetylcholinesterase. The pattern of bands obtained (stained with acetylthiocholine) depended on age, sex, and tissue (i.e., head vs. body part and hemolymph). However, through mixing experiments, it was concluded that most of these apparent differences were due to modification of the enzyme by unknown substances located in the fly's body. The electrophoretic pattern of head acetylcholinesterase was altered so that it became characteristic of the body which was present during extraction. For example, when heads of D. melanogaster were homogenized in an extract from D. lebanonensis bodies, the characteristic AChse bands of melanogaster were absent and instead the bands of lebanonensis were found. it was found that extraction of adult heads in 0.1 M potassium phosphate buffer alone or with a 2-min exposure to 1 mg/ml trypsin at 20 C gave the most reproducible results, independent of age and sex. Using these conditions, 25 strains of D. melanogaster and 30 strains of D. pseudoobscura were examined without finding any reproducible electrophoretic variant of acetylcholinesterase. In addition, 53 strains from 39 other Drosophila species produced a total of only six electrophoretic forms of the head enzyme. Additional electromorphs were found when whole flies were used, but these were not studied in detail because of the possibility that they could be due to postextraction modification.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00484393
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  • 15
    Digitale Medien
    Digitale Medien
    Biochemical and genetic basis of the response to 5-fluorouracil in Drosophila melanogaster (1980)
    Springer
    Biochemical genetics 18 (1980), S. 717-726 
    Details
    ISSN: 1573-4927
    Schlagwort(e): Drosophila ; 5-fluorouracil ; drug response ; thymidylate synthetase
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Mutant strains sensitive and resistant to the drug 5-fluorouracil (FU) have been isolated from the wild-type Pac strain of Drosophila melanogaster. The resistant strain, termed flur, is resistant to at least 0.0035%FU (2.7 × 10−4 m) in the food media and exhibits cross-resistance to 5-fluorodeoxyuridine (FUdR) but not to 5-fluorouridine (FUR). The sensitive strain termed flu S , exhibits over 90% mortality on 0.0008% FU (6 × 10−5 m). Genetic analysis indicates that the flu gene is located on the third chromosome, which agrees with results of previous workers. An analysis of the enzyme thymidylate synthetase from the selected sensitive and resistant strains indicates that the resistant strain enzyme possesses an elevated specific activity. Levels 4 times that of the sensitive strain were observed when the enzymes were assayed at 20 C. This increase is apparently not due to induction by FU in the food media. It is suggested that the enzyme thymidylate synthetase may be involved in the resistance process.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00484588
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  • 16
    Digitale Medien
    Digitale Medien
    Developmental regulation of phenylalanine hydroxylase activity in Drosophila melanogaster (1980)
    Springer
    Biochemical genetics 18 (1980), S. 781-791 
    Details
    ISSN: 1573-4927
    Schlagwort(e): Drosophila ; phenylalanine hydroxylase ; developmental regulation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Herein we demonstrate that Drosophila larvae possess a synthetic activity capable of converting phenylalanine to tyrosine. This system is readily extractable and displays many characteristics of phenylalanine hydroxylase systems described in other organisms, the most notable being that a tetrahydropteridine is required for full expression of activity. The level of phenylalanine hydroxylase activity present in the organism varies with the stage of development: from an undetected level of activity at the first larval instar, there is a rapid increase in phenylalanine hydroxylase activity which reaches a peak at the time of puparium formation, after which there is a rapid decrease again to an undetected level.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00484593
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  • 17
    Digitale Medien
    Digitale Medien
    Genetics of male-specific glucose oxidase and the identification of other unusual hexose enzymes in Drosophila melanogaster (1980)
    Springer
    Biochemical genetics 18 (1980), S. 929-937 
    Details
    ISSN: 1573-4927
    Schlagwort(e): glucose oxidase ; glucose metabolism ; Drosophila ; sex specific
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract A glucose oxidase (GO) has been identified in the ejaculatory duct of male Drosophila melanogaster. Evidence is given that this enzyme was previously misidentified as HEX-1. Genetic analysis indicates that the Go structural gene is located on the third chromosome at 48 ± 0.5 cm. Go is polymorphic in males in populations of D. melanogaster and D. simulans located in Athens, Georgia. Two other hexose enzymes have also been tentatively identified for the first time in Drosophila. These are NAD(P)-glucose dehydrogenase (GODH) and NAD-gluconate dehydrogenase (GNDH). GODH and GNDH are found in both males and females and may circumvent the initial steps in the pentose shunt.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00500125
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  • 18
    Digitale Medien
    Digitale Medien
    Sexual isolation among widely distributed populations ofDrosophila immigrans (1980)
    Springer
    Behavior genetics 10 (1980), S. 401-407 
    Details
    ISSN: 1573-3297
    Schlagwort(e): sexual isolation ; Drosophila ; geographic distance ; isolation index ; resource utilization
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Six strains of the cosmopolitan speciesD. immigrans from the Australian life zone plus one from the USA, show weak sexual isolation and more rarely sexual selection. Levels of sexual isolation cannot be related to geographic distances. Assortative mating may have evolved as a byproduct of ecological divergence.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01065601
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  • 19
    Digitale Medien
    Digitale Medien
    Adaptive strategies in natural populations of Drosophila (1980)
    Springer
    Theoretical and applied genetics 57 (1980), S. 257-266 
    Details
    ISSN: 1432-2242
    Schlagwort(e): Drosophila ; Ethanol ; Climatic races ; Desiccation ; Development times
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Adult tolerance of ethanol vapour in a closed system containing 12% ethanol in solution, decreases in a cline from southern to northern Australia. However a Darwin population is more tolerant than predicted from its latitude. Ethanol tolerance races in Australia have almost certainly evolved within the last 100–150 years, because of resource unavailability prior to that time. Within populations, variation among isofemale strains is lowest in the climatically extreme southern Melbourne (37°S) and northern Darwin and Melville I. (11–12°S) populations. This suggests low resource diversity within extreme populations compared with the climatically less extreme Brisbane (28°S) and especially Townsville (19°S) populations. For desiccation resistance, the population rankings are: Darwin Melbourne 〉 Townsville 〉 Brisbane Melville I. and for development time, rankings are similar: Darwin Melbourne 〈 Townsville 〈 Brisbane Melville I. Therefore resource utilization heterogeneity is greatest in populations not greatly stressed by desiccation and where development times are extended. In total therefore, the utilization of a diversity of resources is a feature of populations tending somewhat towards a K-strategy; this is emphasized by the relative heterogeneity among isofemale strains of these populations for desiccation resistance and to a lesser extent development times. The D. melanogaster gene pool can be viewed as made up of climate-associated races. Since the ethanol tolerances of adjacent (and climatically similar) Darwin and Melville I. are very different, resource utilization races may occur within climatic races. Such a mosaic of resource utilization races are more likely in climatically extreme than in optimal habitats.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00264952
    Standort Signatur Erwartet Verfügbarkeit
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  • 20
    Digitale Medien
    Digitale Medien
    Mutant fs(1) 1163 of Drosophila melanogaster alters yolk protein secretion from the fat body (1980)
    Springer
    Molecular genetics and genomics 180 (1980), S. 411-418 
    Details
    ISSN: 1617-4623
    Schlagwort(e): Drosophila ; Vitellogenin ; Female-sterile mutant ; Protein processing
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The mutant fs(1) 1163 of Drosophila melanogaster, which was isolated by Gans et al. (1975) is a recessive homozygous female sterile at 18°C and a dominant female — sterile at 29°C. We reported previously that there are reduced quantities of the largest of the three yolk polypeptides in Drosophila melanogaster in the haemolymph and eggs of this mutant at 29°C (Bownes and Hames 1978 a). In this paper we show that the yolk protein defect maps within approximately 2.5 recombination units of the female sterility at 21±2.5 map units on the X-chromosome. The temperature-sensitive period of the yolk protein defect is after emergence. In vitro labelling of fs(1) 1163 ovaries and fat bodies showed that they were able to synthesise yolk polypeptide 1. Interestingly, studies on the proteins present in the various tissues indicate that the fat body tends to accumulate all three yolk polypeptides in the mutant. This phenotype is partially co-dominant in that an effect is seen in heterozygotes as well as homozygotes and is enhanced by increased temperature. This mutant could therefore have a defect (a) in the structural gene for yolk polypeptide 1, (b) in the processing and secretion enzyme systems; (c) in the fat body or all tissues leading to altered secretion properties. Mutants like fs(1) 1163 which alter specific steps in vitellogenesis should be of value for analysing the genetic and biochemical control of the synthesis, transport and sequestering of the yolk polypeptides during oogenesis.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00425856
    Standort Signatur Erwartet Verfügbarkeit
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  • 21
    Digitale Medien
    Digitale Medien
    Relationship between ADH activity and behavioral response to environmental alcohol inDrosophila (1980)
    Springer
    Behavior genetics 10 (1980), S. 237-249 
    Details
    ISSN: 1573-3297
    Schlagwort(e): Drosophila ; behavior ; ADH activity ; adaptation ; evolution ; alcohol avoidance ; Adh genotypes
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Three alcohol dehydrogenase genotypes, homozygous for either the electrophoretically fast, slow, or null allele at theAdh locus inD. melanogaster, were tested for relative larval alcohol preference behavior (APB) over a range of ethanol concentrations. Differences in behavior between genotypes were not significant at concentrations below 10%. At concentrations greater than 10%, avoidance behavior was negatively correlated with the relative ADH activity levels of the genotypes tested. A model based on the differential buildup of toxic acetaldehyde is proposed to explain the avoidance response.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01067770
    Standort Signatur Erwartet Verfügbarkeit
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  • 22
    Digitale Medien
    Digitale Medien
    Mapping stimulus-induced nervous activity in small brains by [3H]2-deoxy-D-glucose (1980)
    Springer
    Cell & tissue research 211 (1980), S. 51-64 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Cerebral glucose utilization ; Deoxyglucose method ; Dry autoradiography ; Insect brain ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Nervous activity may be localized in anatomical sections of brain tissue by the autoradiographic deoxyglucose technique. The method provides sufficient structural preservation and spatial resolution for detailed functional investigation of complex but small-sized nervous systems when the original technique is modified as follows: (i) use of 3H instead of 14C as radioactive label, (ii) application of labeled deoxyglucose in concentrations close to physiological glucose levels rather than in trace amounts, (iii) stimulation for 4–9 h after deoxyglucose application instead of 20–45 min, (iv) subsequent preparation avoiding aqueous phases at all stages from fixation to autoradiography, and (v) plastic embedding of the tissue such that serial semithin sections of good structural preservation may be routinely cut. Brief aqueous fixation and dehydration at room temperature as has been described for vertebrates apparently cannot preserve stimulus-induced distribution of radioactive label in the brain of the fly Drosophila melanogaster. Aspects of the results that illustrate the potential and some limitations of the present technique are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00233722
    Standort Signatur Erwartet Verfügbarkeit
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