Amylase gene duplication: an ancestral trait in the Drosophila melanogaster species subgroup
Amylase gene duplication: an ancestral trait in the Drosophila melanogaster species subgroup
复制标题
淀粉酶基因复制：果蝇物种亚群的祖先特征
作者：
O. Daïnou;M. Cariou;J. David;D. Hickey
在黑腹果蝇和拟果蝇这两个世界性同胞物种的 45 个地理种群以及黑腹果蝇亚群中其他 6 个物种的 1 至 3 个种群或品系中研究了淀粉酶的电泳多态性。仅有少数菌株可用的两个物种，D.ectera 和 D.orena，是单态的。在其他物种中鉴定出 2 或 3 个淀粉酶变体，而在黑腹果蝇中鉴定出 12 个电泳变体。总共观察到 17 种不同的淀粉酶同工酶。黑腹果蝇和其他物种之间多态性水平的差异不能简单地用前一个物种中重复的发生来解释。遗传分析表明至少有 4 个其他物种存在重复，即 D. simulans、D. mauritiana、D. yakuba 和 D. teissieri。因此，有人认为重复发生在共同的祖先中，并讨论了这些观察结果的系统发育意义。
Electrophoretic polymorphism of amylases was studied in 45 geographic populations of the two cosmopolitan sibling species, D. melanogaster and D. simulons, and in one to three populations or strains of six other species in the D. melanogaster subgroup. Two species, D. erecta and D. orena, for which only a few strains were available were monomorphic. In the other species 2 or 3 amylase variants were identified while in D. melanogaster, 12 electrophoretic variants were characterized. Altogether 17 different amylase isozymes have been observed. The contrast in the level of polymorphism between D. melanogaster and the other species cannot be explained simply by the occurrence of a duplication in the former species. Genetic analysis demonstrated the existence of a duplication in at least 4 other species, namely D. simulans, D. mauritiana, D. yakuba, and D. teissieri. It is therefore suggested that the duplication occurred in a common ancestor and the phylogenetic implications of these observations are discussed.