Genetic architecture of a morphological shape difference between two Drosophila species.
Genetic architecture of a morphological shape difference between two Drosophila species.
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DOI：
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发表时间：
2000
期刊：
影响因子：
3.3
通讯作者：
Zhao-Bang Zeng;Jianjun Liu;L. F. Stam;C. Kao;J. Mercer;C. Laurie
中科院分区：
文献类型：
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作者：
Zhao-Bang Zeng;Jianjun Liu;L. F. Stam;C. Kao;J. Mercer;C. Laurie
雄性生殖弓后叶的大小和形状在拟果蝇和毛里求斯果蝇之间有很大的不同。这种差异可以用基于椭圆傅里叶和主成分分析的形态测量描述符（PC1）来量化。应用数量性状位点（QTL）定位方法分离回交群体，研究了PC1种间差异的遗传基础。回交群体的亲本差异（35个环境标准差）和PC1遗传力（约90%）都非常大。利用多区间作图，给出了19个不同QTL的证据。最大的加性效应估计占11。4%的亲本差异，但可能代表多个紧密连锁的QTL。基因座间的显性参数估计各不相同，从基本无显性到完全显性，毛里求斯等位基因往往比模拟等位基因占优势。上位性作为变异的来源似乎相对不重要。除了一个外，所有的加性效应估计都有相同的符号，这意味着一个物种几乎所有的等位基因都是正的，而另一个物种几乎所有的等位基因都是负的。这一结果在许多进化情况下都是出乎意料的，并表明了作用于后叶的强烈方向选择的历史。
The size and shape of the posterior lobe of the male genital arch differs dramatically between Drosophila simulans and D. mauritiana. This difference can be quantified with a morphometric descriptor (PC1) based on elliptical Fourier and principal components analyses. The genetic basis of the interspecific difference in PC1 was investigated by the application of quantitative trait locus (QTL) mapping procedures to segregating backcross populations. The parental difference (35 environmental standard deviations) and the heritability of PC1 in backcross populations (>90%) are both very large. The use of multiple interval mapping gives evidence for 19 different QTL. The greatest additive effect estimate accounts for 11. 4% of the parental difference but could represent multiple closely linked QTL. Dominance parameter estimates vary among loci from essentially no dominance to complete dominance, and mauritiana alleles tend to be dominant over simulans alleles. Epistasis appears to be relatively unimportant as a source of variation. All but one of the additive effect estimates have the same sign, which means that one species has nearly all plus alleles and the other nearly all minus alleles. This result is unexpected under many evolutionary scenarios and suggests a history of strong directional selection acting on the posterior lobe.