Functional divergence caused by ancient positive selection of a Drosophila hybrid incompatibility locus.
Functional divergence caused by ancient positive selection of a Drosophila hybrid incompatibility locus.
复制标题
DOI：
10.1371/journal.pbio.0020142
复制
发表时间：
2004-06
期刊：
影响因子：
9.8
通讯作者：
Tarone AM
中科院分区：
文献类型：
--
作者：
Barbash DA;Awadalla P;Tarone AM
种间杂交致死性和不育性是物种间分化进化的结果，并用于维持物种的离散特性。Dobzansky和Muller在广泛接受的模型中描述了杂交不亲和性的进化，其中谱系特异的功能差异是杂交不亲和性基因的基本特征。识别和测试候选杂交不亲和性基因需要实验上易于处理的模型。几个与杂交不亲和性有关的果蝇黑腹果蝇基因已经被鉴定出来，但还没有一个基因被证明在功能上与Dobzhansky-Muller模型一致。通过将X-连锁杂交雄性救援(HMR)基因的转基因拷贝从其近缘物种拟南氏丝虫和毛滴虫中导入黑腹盘藻，我们证明了HMR在功能上的分化导致了这两个物种之间的F1杂交不亲和性。与Dobzansky-Muller模型一致的是，我们发现HmR在黑腹黑腹蛇的谱系中存在广泛的分歧，但我们也发现在兄弟种谱系中存在广泛的分歧。总而言之，这些发现暗示HMR编码的13%以上的氨基酸是导致杂交不亲和性的候选。HMR的异常水平的差异不能用中性过程解释，因为我们使用系统发育方法和种群遗传分析来表明，这两个谱系中氨基酸差异的增加是由于遥远的过去-至少一百万代之前的积极选择。我们的发现表明，自然选择驱动的多重替换可能是产生杂交不亲和等位基因所需的普遍现象。转基因实验表明，HMR基因在果蝇及其近缘物种中存在功能分化，并导致种间杂交后代死亡
Interspecific hybrid lethality and sterility are a consequence of divergent evolution between species and serve to maintain the discrete identities of species. The evolution of hybrid incompatibilities has been described in widely accepted models by Dobzhansky and Muller where lineage-specific functional divergence is the essential characteristic of hybrid incompatibility genes. Experimentally tractable models are required to identify and test candidate hybrid incompatibility genes. Several Drosophila melanogaster genes involved in hybrid incompatibility have been identified but none has yet been shown to have functionally diverged in accordance with the Dobzhansky-Muller model. By introducing transgenic copies of the X-linked Hybrid male rescue (Hmr) gene into D. melanogaster from its sibling species D. simulans and D. mauritiana, we demonstrate that Hmr has functionally diverged to cause F1 hybrid incompatibility between these species. Consistent with the Dobzhansky-Muller model, we find that Hmr has diverged extensively in the D. melanogaster lineage, but we also find extensive divergence in the sibling-species lineage. Together, these findings implicate over 13% of the amino acids encoded by Hmr as candidates for causing hybrid incompatibility. The exceptional level of divergence at Hmr cannot be explained by neutral processes because we use phylogenetic methods and population genetic analyses to show that the elevated amino-acid divergence in both lineages is due to positive selection in the distant past—at least one million generations ago. Our findings suggest that multiple substitutions driven by natural selection may be a general phenomenon required to generate hybrid incompatibility alleles. Transgenic experiments show that the HMR gene has functionally diverged in Drosophila melanogaster and its sibling species and causes the death of hybrid offspring in interspecific crosses
登录
查看更多内容
影响因子：
64.8
作者：
HUTTER, P;ASHBURNER, M
通讯作者：
ASHBURNER, M
DOI：
10.1098/rstb.1998.0208
发表时间：
1998-02-28
影响因子：
6.3
作者：
Parker, GA;Partridge, L
通讯作者：
Partridge, L
影响因子：
64.8
作者：
MCDONALD, JH;KREITMAN, M
通讯作者：
KREITMAN, M
DOI：
10.1073/pnas.212277199
发表时间：
2002-10-15
影响因子：
11.1
作者：
Betancourt, AJ;Presgraves, DC
通讯作者：
Presgraves, DC
DOI：
10.1073/pnas.94.15.7730
发表时间：
1997-07-22
影响因子：
11.1
作者：
Clark, AG
通讯作者：
Clark, AG