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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Biochemical genetics 13 (1975), S. 45-51 
    ISSN: 1573-4927
    Keywords: gene action ; polyploidy ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In phylogenetically diploid and tetraploid Cyprinid fish species, erythrocyte volumes, protein contents, and mean activities of the enzymes LDH, 6PGD, and PGI per cell per active gene locus decline with increasing DNA contents. These findings are assumed to reflect an evolutionary tendency of polyploids to regulate their genic activity down to the level of the diploids.
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  • 2
    ISSN: 1573-4927
    Keywords: cell size ; evolution ; gene action ; isoenzymes ; polyplodiy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract By use of cell size, protein and hemoglobin content, and enzyme activities as markers, it becomes apparent that in the course of evolution the gene expression of anciently tetraploid fish of the order Ostariophysi was diploidized, but no such regulatory mechanism has evolved in the phylogenetically tetraploid species of the order Isospondyli. This finding is discussed in terms of possible selective neutrality of tetraploid expression and the phylogenetic age of Isospondyli.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Biochemical genetics 13 (1975), S. 743-757 
    ISSN: 1573-4927
    Keywords: primate hemoglobins ; antigenicity ; evolution ; radioimmunoassay
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The antigenic properties of a number of chromatographically purified primate hemoglobins were compared to those of normal human hemoglobin using a sensitive radioimmunochemical procedure. The degree of inhibition of the antigen-antibody reaction with heterologous hemoglobins appeared to be related to the structural similarity of these proteins to the normal human hemoglobin immunogen. With the exception of the baboon hemoglobin, the antigenicity of the hemoglobins paralleled the phylogeny of the primates. The gorilla and chimpanzee hemoglobins were antigenically identical to normal human hemoglobin, whereas the gibbon and orangutan hemoglobins were substantially more variable. Of the Old World monkey hemoglobins examined, the baboon produced lower inhibition values, suggesting a greater degree of structural dissimilarity than other Cercopithecoidea hemoglobins, which is compatible with a greater rate of evolutionary change occurring in this protein. Using the known amino acid sequences of human and other primate hemoglobins, we have attempted to identify antigenic determinant areas of the proteins.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Plant systematics and evolution 123 (1975), S. 107-115 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Asteraceae ; Centaurea ; Chromosome numbers ; Flora of the Mediterranean and C. Europe
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The chromosome numbers of several Mediterranean and Central European species from the genusCentaurea L. have been studied. The material was collected in natural habitats, exceptC. thracica andC. maxima. The numbers forC. cineraria (2n = 36; tetraploid!),C. subtilis (2n = 22),C. sonchifolia (2n = 44),C. sphaerocephala (2n = 44),C. napifolia (2n = 22),C. achaia (2n = 22),C. thracica (2n = 18), andC. maxima (2n = 28) are reported for the first time. For the following species earlier counts are confirmed:C. cineraria (diploid, 2n = 18),C. maculosa (2n = 18),C. rhenana (2n = 18),C. triumfettii (2n = 22 + 0−1 B; first report of accessory chromosome for this species),C. scabiosa (2n = 20 + 0−3 B),C. crassifolia (2n = 30). B-chromosomes are reported for 3 populations ofCentaurea scabiosa from Berlin; they lack in 2 populations from Bayern and Hessen.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Plant systematics and evolution 124 (1975), S. 125-138 
    ISSN: 1615-6110
    Keywords: Orchidaceae ; Ophrys ; comb. nov. ; O. holosericea subsp.gracilis ; subsp.parvimaculata ; subsp.pollinensis ; O. sipontensis ; Chromosome numbers: polyploidy ; aneuploidy ; aneusomaty ; B-chromosomes ; chromosome technique ; kinetochore staining ; hybridization ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The diploid basic chromosome number forOphrys is 2n = 36. Tetraploidy has been found inO. fusca agg. only. Aneuploidy and aneusomaty are wide-spread; supernumerary chromosomes behave B-like, but do not differ by shape or structure from A-chromosomes. A new staining method reveals clearly differentiated bipartite meiotic kinetochores. Evolutionary aspects of homogamic hybridization, chromosome instability, and of the basic chromosome number x = 18 are discussed.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Biochemical genetics 14 (1976), S. 19-26 
    ISSN: 1573-4927
    Keywords: evolution ; polyploidy ; ribosomal RNA genes ; cyprinid fish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Phylogenetically diploid and tetraploid cyprinid fish species have cells of very similar volumes and protein contents. This finding has prompted us to postulate a regulatory system established during the evolution of the tetraploids leading to a diploid state of genic expression. It was proposed that this might be accounted for by a selective loss of ribosomal genes. RNA-DNA hybridization experiments, however, reveal a clear-cut 1:2 relationship of ribosomal DNA amounts between the diploid and the tetraploid species.
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  • 7
    ISSN: 1573-4927
    Keywords: evolution ; polyploidy ; RNA content ; protein content ; enzyme activities ; Cyprinidae ; Isospondyli
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The ratio of cellular RNA and protein content is about 1:1 between phylogenetically diploid and tetraploid species of the teleost family Cyprinidae, but is roughly in proportion to ploidy in species of the teleost order Isospondyli. Enzyme activities do not unequivocally comply with this scheme. These findings are discussed in view of the hypothesis that a regulatory mechanism which reduces genic activity has evolved in the tetraploid cyprinids but not in the tetraploid species of the order Isospondyli.
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  • 8
    ISSN: 1573-4927
    Keywords: Triticum ; acid phosphatase ; isozymes ; developmental genetics ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The tissue and developmental specificities of the acid phosphatase (ACPH) isozymes of Triticum aestivum and its progenitor species T. turgidum and T. tauschii have been determined and compared using the zymogram technique. Tissue and/or developmental variation in relative staining intensity, suggestive of variation in the quantity of active enzyme present, was observed for each of the seven major isozymes expressed. Isozymes homologous to each of the major isozymes of the hexaploid were detected in one or the other of the progenitor species. No difference in the pattern of developmental or tissue specificity was observed between the species for any isozyme. However, ACPH-4, encoded by Acph4, a structural gene linked to chromosome 4A, differs in electrophoretic mobility between T. aestivum and T. turgidum, indicating that divergence has occurred between these species at the Acph4 locus since the origin of the hexaploid. The molecular weight of each of five ACPH isozymes of the hexaploid was determined to be approximately 58,000. This finding, plus the results of the developmental study and the earlier demonstration that the structural genes for six isozymes (including four of those whose molecular weight was determined) are linked to homoeologous chromosomes, provides evidence in support of the suggestion that the ACPH structural genes of hexaploid wheat are homoeologously related.
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  • 9
    ISSN: 1573-4927
    Keywords: evolution ; polyploidy ; ribosomal RNA genes ; Isospondyli
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Phylogenetically tetraploid species of the fish order Isospondyli generally have twice the mean ribosomal gene content as closely related species on the phylogenetically diploid level. Considerable intraspecific variation of rDNA amount was observed. These findings are discussed in view of the hypothesis that selective loss of ribosomal genes may account for diminishing genic activity in phylogenetically tetraploid organisms.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Plant systematics and evolution 125 (1976), S. 179-187 
    ISSN: 1615-6110
    Keywords: Species problem ; numerical phenetics ; phenetic bottlenecks ; computers ; multivariate analyses ; geographic variation ; cladistics ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The use of numbers by systematists is not new. Measurements to describe individuals and formal taxa have been used since the beginnings of our science. But the advent of electronic computers now permits a much more accurate understanding of the phenotypic relationships within and among populations and taxa. Furthermore, estimates of cladistic relationship also are being attempted with the help of computers. Computers can increase our understanding of speciation, but this requires us to think intelligently about the meaning of their results.
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