Data_Sheet_1_Rapid Evolution of Autosomal Binding Sites of the Dosage Compensation Complex in Drosophila melanogaster and Its Association With Transcription Divergence.zip

How pleiotropy influences evolution of protein sequence remains unclear. The male-specific lethal (MSL) complex in Drosophila mediates dosage compensation by 2-fold upregulation of the X chromosome in males. Nevertheless, several MSL proteins also bind autosomes and likely perform functions not related to dosage compensation. Here, we study the evolution of MOF, MSL1, and MSL2 biding sites in Drosophila melanogaster and its close relative Drosophila simulans. We found pervasive expansion of the MSL binding sites in D. melanogaster, particularly on autosomes. The majority of these newly-bound regions are unlikely to function in dosage compensation and associated with an increase in expression divergence between D. melanogaster and D. simulans. While dosage-compensation related sites show clear signatures of adaptive evolution, these signatures are even more marked among autosomal regions. Our study points to an intriguing avenue of investigation of pleiotropy as a mechanism promoting rapid protein sequence evolution.

多效性如何影响蛋白质序列的进化机制尚不明确。果蝇中的男性特异性致死（MSL）复合体通过将X染色体在雄性中的表达量上调两倍来介导剂量补偿。然而，多个MSL蛋白也结合常染色体，并可能执行与剂量补偿无关的功能。在本研究中，我们探讨了果蝇黑腹果蝇及其近亲果蝇模拟蝇中MOF、MSL1和MSL2结合位点的进化。我们发现MSL结合位点在黑腹果蝇中普遍扩张，尤其是在常染色体上。这些新结合区域中的大多数不太可能参与剂量补偿，且与黑腹果蝇和模拟蝇之间表达差异的增加有关。虽然与剂量补偿相关的位点显示出适应性进化的明显特征，但这些特征在常染色体区域中表现得更为显著。我们的研究指向了探究多效性作为促进蛋白质序列快速进化的机制的一个引人入胜的研究方向。