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Sibling species groups are suitable models for the understanding of inter‐ and intraspecific processes in taxonomy and biogeography. We analysed 262 individuals from the Alps of the Coenonympha arcania/gardetta species complex by allozyme electrophoresis. These taxa showed high variance amongst populations (FST: 0.391) and strong intertaxon genetic differentiation (FCT: 0.376). Although morphologically similar, Coenonympha gardetta and Coenonympha arcania clearly differ in their genetic characteristics; the morphologically intermediate taxa Coenonympha darwiniana darwiniana and Coenonympha darwiniana macromma are genetically well distinguished from each other and the two other taxa. Coenonympha arcania and C. d. macromma most probably share a common ancestor and evolved by cladogenesis, whereas the taxonomic situation of C. d. darwiniana is still unresolved: This taxon might be the result of hybridization between C. arcania and C. gardetta or it might have a common ancestor together with C. gardetta. We suggest species rank for all four taxa. The distribution of genetic diversity of these populations and the differentiation amongst populations suggest rather different biogeographical scenarios: C. arcania most probably is of Mediterranean origin with postglacial range expansion northwards; C. gardetta survived the last ice age in peripheral refugia of the Alps and has spread all over this high mountain system in the postglacial; C. darwiniana and C. macromma survived the Würm in geographic proximity to their actual distribution areas and only have performed moderate uphill translocations during postglacial warming. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 890–904. 相似文献
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Takeo Kishimoto 《Biology of the cell / under the auspices of the European Cell Biology Organization》2005,97(5):349-350
André Picard, a cell and developmental biologist of starfish oocytes, died on 21 November 2004 at the age of 54 after a three‐year battle with prostate cancer. He was a Research Director of the CNRS at the Laboratoire Arago in Banyuls, France, and was awarded the Prix Foulon from the French Academy of Sciences in 2003. 相似文献
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Claudine Marriq Martine Sciaky Nicole Giraud Danile Foveau Georgette Laurent-Tabusse 《Biochimie》1974,55(11-12)
The amino acid sequence of the IICNBr fragment of the human erythrocyte carbonic anhydrase B has been determined. This fragment contains the first 148 of the 260 residues of the N-acetylated single polypeptide chain of the protein. After tryptic hydrolysis of this fragment, eleven peptides have been isolated by gel filtration and chromatography on Dowex 50 W-X2 or DEAE-Sephadex. Eight of them were identified with already sequenced peptides previously isolated from tryptic hydrolysate of the whole protein. The other three ones were obtained in pure form and sequenced. The combined amino acid content of these eleven peptides only account for 124 of the 148 amino acid residues in the IICNBr fragment. The tryptic attack of the maleylated IICNBr fragment gave three peptides as was expected from the number of arginine residues (2) in this fragment: two arginyl peptides (II1, II3) and one homoseryl peptide (II2). They were purified by gel filtration. The unidentified 24 residue tryptic peptide has been isolated from the demaleylated II2 tryptic hydrolysate and sequenced. The order of the twelve tryptic peptides of IICNBr fragment has been obtained by study of chymotrypsic peptides isolated from II1 and IICNBr fragment. 相似文献
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The thermal stabilization and the configurational changes of DNA were studied during the binding process of silver ion. Melting curves of silver–DNA complexes were analyzed according to the method of Felsenfeld. An increase of Tm occurred during the formation of the first complex with a preferential stabilization of G–C pairs. In the case of DNA from H. influenzae, the transforming power was maintained after heating in presence of silver at a temperature where AT pairs were dissociated but G-C pairs were not. Shape modifications of the molecule were followed by light scattering, both with native and ultrasonic degraded DNA. In the case of native DNA, the binding of positive ions modified the electrostatic potential and increased the flexibility of the molecule. In the case of rod shaped fragments of DNA, the progressive formation of a kind of polyampholyte was accompanied by aggregation phenomena. The formation of the second complex, with proton release, induced changes of secondary structure and possibly a tilt of the plane of the base. 相似文献
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