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Biochemical Genetics (v.41, #5-6)
Biochemical Genetic Variability in Brown Hares (Lepus europaeus) from Greece by Franz Suchentrunk; Zissis Mamuris; Athanassios I. Sfougaris; Costas Stamatis (pp. 127-140).
Allozyme variability of 91 brown hares (Lepus europaeus) from seven regions in Greece was compared to existing data of Bulgarian populations to test the hypothesis of the occurrence of specific alleles in Greece, likely stemming from an isolated Late Pleistocene refugial population in the southern Balkans. This hypothesis is particularly suggested by some subfossil Late Pleistocene hare remains in Greece and the reported high mtDNA diversity in Greek hares. Allozymic diversity could be higher in Greek hares than in hares from neighboring regions as a result of the accumulation of variants in a long-lasting Pleistocene refugium. Conversely, Greek hares could exhibit reduced genetic diversity because of long-lasting low effective population sizes during the Late Glacial Maximum and a lower chance of postglacial gene flow from other populations into this rather marginal part in the southern Balkans. Horizontal starch gel electrophoresis of proteins from 35~loci revealed three alleles (Es-1 −162, Pep-2 114, Mpi 88) at low frequencies, which were not found in Bulgarian or any other brown hare population. In contrast, some alleles from the populations from Bulgaria and other regions of Europe were absent in the Greek samples. Population genetic statistics indicated only a slight tendency of increased gene pool diversity in Greek hares, little substructuring in Greek and Bulgarian populations, respectively, as well as an only slightly lower level of gene flow between the two neighboring regions, as compared to the gene flow within each region. The results conform to the hypothesis of a Late Pleistocene refugial population in the southern Balkans, with some few specific nuclear gene pool characteristics, but little effect on the overall genetic differentiation between Greek and Bulgarian hares.
Keywords: brown hare; Lepus europaeus ; allozymes; population genetics; Greece; Mediterranean
Studies on a Heterologous Complex Formed by Human Butyrylcholinesterase by R. L. R. Souza; L. Furtado; A. C. P. Diniz; A. C. D. Silva; J. Kaiss; M. L. Petzl-Erler; E. A. Chautard-Freire-Maia (pp. 141-150).
An electrophoretic band with butyrylcholinesterase activity was detected in 71 CHE2 C5+ and 378 CHE2 C5− individuals and was named C4/5 in view of its similar mobility to either C4 or C5, depending on the pH of the agar gel used. The present data suggest that C4/5 is a heterologous complex of butyrylcholinesterase. Although the C4/5 band may have the same mobility as C5, depending on the conditions of electrophoresis, our hypothesis is that these two bands result from the association of BChE with different molecules.
Keywords: serum cholinesterase; BCHE locus; CHE2 locus; C4/5 and C5 bands
Prophenol Oxidase A3 in Drosophila melanogaster: Activation and the PCR-Based cDNA Sequence by Nobuhiko Asada; Genta Yokoyama; Nobuko Kawamoto; Shigemi Norioka; Takashi Hatta (pp. 151-163).
Phenol oxidase exists in Drosophila hemolymph as a prophenol oxidase, A1 and A3, that is activated in vivo with a native activating system, AMM-1, by limited proteolysis with time. The polypeptide in purified prophenol oxidase A3 has a molecular weight of approximately 77,000 Da. A PCR-based cDNA sequence coding A3 has 2501 bp encoding an open reading frame of 682 amino acid residues. The potential copper-binding sites, from Trp-196 to Tyr-245, and from Asn-366 to Phe-421, are highly homologous to the corresponding sites in other invertebrates. The availability of prophenol oxidase cDNA should be useful in revealing the biochemical differences between A1 and A3 isoforms in Drosophila melanogaster that are refractory or unable to activate prophenol oxidase.
Keywords: Drosophila ; phenol oxidase; proteolysis; cDNA
Molecular Cloning and Characterization of a Novel Human Hydroxysteroid Dehydrogenase-Like 2 (HSDL2) cDNA from Fetal Brain by Jianfeng Dai; Yi Xie; Qihan Wu; Liu Wang; Gang Yin; Xin Ye; Li Zeng; Jian Xu; Chaoneng Ji; Shaohua Gu; Qingshan Huang; Robert Chunhua Zhao; Yumin Mao (pp. 165-174).
Hydroxysteroid dehydrogenases (HSDs) are responsible for the biosynthesis of steroid hormones and play a crucial role in mammalian physiology and development. By large-scale sequencing analysis of a human fetal brain cDNA library, we isolated a novel human hydroxysteroid dehydrogenase-like cDNA (HSDL2). This cDNA is 3211 bp in length, encoding a 418–amino-acid polypeptide, which contains a typical motif for NAD(P)+-binding (TGxxxGxG), an SDR active site motif (S-Y-K) and a sterol carrier protein domain. HSDL2 shows high similarity with the homologues in the mouse and fruit fly. The HSDL2 gene is mapped to chromosome 9q32 and contains 11 exons. RT-PCR analysis shows that the HSDL2 gene is widely expressed in human tissues and the expression levels in liver, kidney, prostate, testis, and ovary are relatively high.
Keywords: SDR; HSDL2 gene; SCP2; expression pattern
An RAPD (Random Amplified Polymorphic DNA) Analysis of Genetic Population Structure of Balea biplicata (Gastropoda: Clausiliidae) in Fragmented Floodplain Forests of the Elster/Saale Riparian System by A. Hille; K. Liebal; B. Mosch; H. Pellmann; M. Schlegel (pp. 175-199).
Eight German populations of the land snail Balea biplicata(Mollusca: Clausiliidae) were studied using the randomly amplified polymorphic DNA-polymerase chain reaction and morphometrics (principal component and discriminant analysis) to examine population structure and gene flow patterns in a fragmented landscape mosaic along the Elster/Saale riparian system, Germany. A variety of population genetic analyses targeting either more on the geographic scale of gene flow (genetic distances, F statistics, Mantel test) or on local genotypic structure (heterozygosity, linkage disequilibrium, bottleneck probability) showed that (1) the population system in total is governed by high gene flow independent of geographic distance, (2) genetic structure on the narrower sampling scale is mainly determined by stochastic processes due to genetic drift in small isolated and frequently recolonized populations, and (3) the morphometrical variation of the populations was related neither to habitat nor to genetic heterogeneity. The potentials for active and passive dispersal capacity of the snails and possible environmental impacts on their population structure are discussed.
Keywords: Balea biplicata ; random amplified polymorphic DNA; morphometry; gene flow and population structure; landscape fragmentation
Identification of the Binding Domain of Signal-Transduction-Related Proteins on c-Mpl
by Limin Yang; Libing Feng; Li Huang; Weiguo Zhou; Min Wan; Shouyuan Zhao; Changben Li (pp. 201-208).