Gu Hongchang, Wang Liang, Lv Xueze, Yang Weifang, Zhang Li, Zhang Zebin, Zhu Tao, Jia Yaxiong, Chen Yu, Qu Lujiang
Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agriculture and Forestry Sciences, Beijing, People's Republic of China.
Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, People's Republic of China.
R Soc Open Sci. 2023 Apr 5;10(4):221313. doi: 10.1098/rsos.221313. eCollection 2023 Apr.
Genes with sex-biased expression are thought to underlie sexually dimorphic phenotypes and are therefore subject to different selection pressures in males and females. Many authors have proposed that sexual conflict leads to the evolution of sex-biased expression, which allows males and females to reach separate phenotypic and fitness optima. The selection pressures associated with domestication may cause changes in population architectures and mating systems, which in turn can alter their direction and strength. We compared sex-biased expression and genetic signatures in wild and domestic ducks (), and observed changes of sexual selection and identified the genomic divergence affected by selection forces. The extent of sex-biased expression in both sexes is positively correlated with the level of both d /d and nucleotide diversity. This observed changing pattern may mainly be owing to relaxed genetic constraints. We also demonstrate a clear link between domestication and sex-biased evolutionary rate in a comparative framework. Decreased polymorphism and evolutionary rate in domesticated populations generally matched life-history phenotypes known to experience artificial selection. Taken together, our work suggests the important implications of domestication in sex-biased evolution and the roles of artificial selection and sexual selection for shaping the diversity and evolutionary rate of the genome.
具有性别偏向性表达的基因被认为是两性异形表型的基础，因此在雄性和雌性中受到不同的选择压力。许多作者提出，性冲突导致了性别偏向性表达的进化，这使得雄性和雌性能够达到不同的表型和适合度最优状态。与驯化相关的选择压力可能会导致种群结构和交配系统的变化，进而改变其方向和强度。我们比较了野生和家养鸭子的性别偏向性表达和遗传特征，观察了性选择的变化，并确定了受选择力影响的基因组差异。两性中性别偏向性表达的程度与dN/dS水平和核苷酸多样性均呈正相关。这种观察到的变化模式可能主要是由于遗传限制的放松。我们还在一个比较框架中证明了驯化与性别偏向性进化速率之间的明确联系。驯化种群中多态性和进化速率的降低通常与已知经历人工选择的生活史表型相匹配。综上所述，我们的工作表明驯化在性别偏向性进化中的重要意义，以及人工选择和性选择在塑造基因组多样性和进化速率方面的作用。
