Historical selection, amino acid polymorphism and lineage-specific divergence at the G6pd locus in Drosophila melanogaster and D. simulans.
Historical selection, amino acid polymorphism and lineage-specific divergence at the G6pd locus in Drosophila melanogaster and D. simulans.
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果蝇和模拟果蝇 G6pd 基因座的历史选择、氨基酸多态性和谱系特异性分歧。
DOI：
10.1093/genetics/144.3.1027
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发表时间：
1996
期刊：
影响因子：
3.3
通讯作者：
Verrelli,BC
中科院分区：
文献类型：
--
作者：
Eanes,WF;Kirchner,M;Yoon,J;Biermann,CH;Wang,IN;McCartney,MA;Verrelli,BC
对50只果蝇和12只果蝇G6 pd基因1705 bp的核苷酸多样性进行了研究。simulanslines。我们早期的报告对比了这些物种中沉默位点和替换位点的种内多态性和种间差异。这份报告扩大了欧洲和非洲的线的数量，并检查了多态性的模式，相对于共同的A/peptidzymes。在D. melanogaster中，沉默的核苷酸多样性在不同的地方变化2.8倍。Ballele序列的变异性是A等位基因的2 - 4倍，等位酶之间的差异是Ballele序列的2倍。在G6 pd区域存在很强的连锁不平衡。在这两个物种中，沉默多态性的水平从5′端到3′端增加，而沉默位点的分歧或固定水平没有可比的模式。中性模型在两个物种中都没有被拒绝。使用D. yakubaas a outgroup，theD.黑胃谱系的沉默固定率高两倍，但氨基酸替换率不到一半。在突变固定的血统特异性差异是不一致的中性预期，并建议物种特异性的人口规模差异与弱有利和有害的选择的相互作用。
The nucleotide diversity across 1705 bp of theG6pdgene is studied in 50Drosophila melanogasterand 12D. simulanslines. Our earlier report contrasted intraspecific polymorphism and interspecific differences at silent and replacement sites in these species. This report expands the number of European and African lines and examines the pattern of polymorphism with respect to the commonA/Ballozymes. InD. melanogasterthe silent nucleotide diversity varies 2.8-fold across localities. TheBallele sequences are two- to fourfold more variable than the derivedAallele, and differences between allozymes are twice as amongBalleles. There is strong linkage disequilibrium across theG6pdregion. In both species the level of silent polymorphism increases from the 5′ to 3′ ends, while there is no comparable pattern in level of silent site divergence or fixation. The neutral model is not rejected in either species. UsingD. yakubaas an outgroup, theD. melanogasterlineage shows a twofold greater rate of silent fixation, but less than half the rate of amino acid replacement. Lineage-specific differences in mutation fixation are inconsistent with neutral expectations and suggest the interaction of species-specific population size differences with both weakly advantageous and deleterious selection.