Multiple Quantitative Trait Loci Influence the Shape of a Male-Specific Genital Structure in Drosophila melanogaster.
Multiple Quantitative Trait Loci Influence the Shape of a Male-Specific Genital Structure in Drosophila melanogaster.
复制标题
DOI：
10.1534/g3.111.000661
复制
发表时间：
2011-10
期刊：
影响因子：
--
通讯作者：
Macdonald SJ
中科院分区：
文献类型：
--
作者：
McNeil CL;Bain CL;Macdonald SJ
在进化过程中，雄性生殖器比其他形态特征更快地分化，这在分类学上是普遍存在的，可能是由于某种形式的性选择。阐明作用于这些性状的进化力量的一种方法是详细描述物种内和物种间变异的遗传结构，这是一个在模型系统中更容易处理的研究程序。黑腹果蝇（Drosophilamelanogaster）及其近缘种D. simulans、D. mauritiana和D. sechellia，是形态上可区分的，只有形状的后叶，男性特定的阐述生殖arch. We扩展早期的研究，确定数量性状位点（QTL）负责跨物种的叶分歧，并报告第一个遗传解剖的叶形状变化的物种内。利用一种先进的互交作图设计，我们确定了三个常染色体QTL的差异，在一对D。黑腹菌近交系每个QTL对形状变异的贡献率为4.6-10.7%，其中两个QTL表现出显著的上位性互作。有趣的是，这些种内QTL与种间叶QTL定位在相同的位置，这意味着种内和种间对该性状有一些共同的遗传控制。作为对自然叶形状变异的机械理解的第一步，我们发现我们的QTL数据和一组基因之间的关联，这些基因在发育中的生殖器成虫盘（成人生殖器的前体）中显示出性别偏见的表达。这些基因是很好的候选人，自然隔离多态性有助于后叶形状。
The observation that male genitalia diverge more rapidly than other morphological traits during evolution is taxonomically widespread and likely due to some form of sexual selection. One way to elucidate the evolutionary forces acting on these traits is to detail the genetic architecture of variation both within and between species, a program of research that is considerably more tractable in a model system. Drosophila melanogaster and its sibling species, D. simulans, D. mauritiana, and D. sechellia, are morphologically distinguishable only by the shape of the posterior lobe, a male-specific elaboration of the genital arch. We extend earlier studies identifying quantitative trait loci (QTL) responsible for lobe divergence across species and report the first genetic dissection of lobe shape variation within a species. Using an advanced intercross mapping design, we identify three autosomal QTL contributing to the difference in lobe shape between a pair of D. melanogaster inbred lines. The QTL each contribute 4.6–10.7% to shape variation, and two show a significant epistatic interaction. Interestingly, these intraspecific QTL map to the same locations as interspecific lobe QTL, implying some shared genetic control of the trait within and between species. As a first step toward a mechanistic understanding of natural lobe shape variation, we find an association between our QTL data and a set of genes that show sex-biased expression in the developing genital imaginal disc (the precursor of the adult genitalia). These genes are good candidates to harbor naturally segregating polymorphisms contributing to posterior lobe shape.