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The relative occurrence of outcrossing in two geographical populations of the digenetic trematode Lecithochirium rufoviride was investigated using starch gel electrophoresis to study the polymorphic locus Pgm-1. Assuming that the effects of mutation, genetic drift and natural selection on this locus are negligible, allozyme variation suggests the occurrence of extensive outcrossing in both populations, Ria de Arousa and Lianes (North of Spain). Therefore, the minimum outcrossing rate giving no statistically significant deviation respect to Hardy-Weinberg equilibrium was 70% and 66%, respectively. Despite of the asexual reproduction in the snail host, the possibility of self-fertilization as a component of the breeding system of this hermaphroditic helminth, and a population reproductive structure probably influenced by the habitat fragmentation, these results suggest that populations of this species in the definitive host, the European conger eel (Conger conger), are basically panmictic.
The quaternary structure of ten enzymes in hemiurid flukes of the genus Lecithochirium (Digenea, Hemiuridae) was inferred using allozyme electrophoresis. Allozyme variants with single-banded homozygotes and double-banded heterozygotes characteristic of monomeric enzymes were observed for aconitase, adenosine deaminase and phosphoglucomutase. The phenotypic variation (single-banded and triple-banded profiles) detected for glucose phosphate isomerase, isocitrate dehydrogenase, phosphogluconate dehydrogenase and malate dehydrogenase, suggest a dimeric structure for these enzymes. These results are consistent with structures already known for invertebrates, including parasitic helminths. Atypical heterozygote patterns were observed for fumarase and malic enzyme, both of which revealed monomeric profiles. Moreover, in the genus Lecithochirium, both monomeric and dimeric isozymes for hexokinase may be present. However, there are other possible explanations for the unusual triple-banded pattern detected for this enzyme. The results are discussed in the context of possible variations in subunit number of homologous enzymes within phylogenetically diverse groups such as parasitic helminths, and compared with those of previous studies using allozyme analysis.
Antler traits (length of the main beam, circumference of the main beam, coronet circumference, and the number of antler points) in roe deer Capreolus capreolus (Linnaeus, 1758) from a population in Casentino (Northern Tuscany) were examined for associations with genotypes at loci coding for enzymes. Significant associations were found only in yearlings. Individuals homozygous for the allele Mpi120 had significantly larger antlers than carriers of other genotypes at Mpi. Individuals homozygous for Pep-2100 had significantly smaller antlers than carriers of other genotypes at Pep-2. In adults the results were essentially the same, but only as a statistically insignificant trend. The data were interpreted in terms of one or more genetic components having a major influence on antler development only in yearlings. This corresponds with behavioural data suggesting that in adults antler size is not related to reproductive success, but in yearlings it is correlated with sexual maturity and the rate of being expelled from the home range of their mothers by territory holders. The situation in the roe deer was compared with previous results on the genetics of antler development in the red deer, where males are social rather than solitary, yearlings do not participate in reproduction, and some antler characteristics are related to reproductive success of adult stags.
Allozymic variation was surveyed in 21 European polecats Mustela putorius Linnaeus, 1758 from western France, using starch gel electrophoresis. Fourteen loci were success­fully examined and genetic variation was detected at 28.6% of the loci at the 0.05 level. Heterozygosity level averaged 0.082. European polecats from western France clearly showed significant levels of genetic variability. This result contrasts with previously reported analyses from Danish populations.
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