Animal Biodiversity and Evolution, Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), 08003 Barcelona, Spain.
Center for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, 53113 Bonn, Germany.
Genes (Basel). 2019 Oct 4;10(10):776. doi: 10.3390/genes10100776.
Gene expression profiles can change dramatically between sexes and sex bias may contribute specific macroevolutionary dynamics for sex-biased genes. However, these dynamics are poorly understood at large evolutionary scales due to the paucity of studies that have assessed orthology and functional homology for sex-biased genes and the pleiotropic effects possibly constraining their evolutionary potential. Here, we explore the correlation of sex-biased expression with macroevolutionary processes that are associated with sex-biased genes, including duplications and accelerated evolutionary rates. Specifically, we examined these traits in a group of 44 genes that orchestrate sperm individualization during spermatogenesis, with both unbiased and sex-biased expression. We studied these genes in the broad evolutionary framework of the Insecta, with a particular focus on beetles (order Coleoptera). We studied data mined from 119 insect genomes, including 6 beetle models, and from 19 additional beetle transcriptomes. For the subset of physically and/or genetically interacting proteins, we also analyzed how their network structure may condition the mode of gene evolution. The collection of genes was highly heterogeneous in duplication status, evolutionary rates, and rate stability, but there was statistical evidence for sex bias correlated with faster evolutionary rates, consistent with theoretical predictions. Faster rates were also correlated with clocklike (insect amino acids) and non-clocklike (beetle nucleotides) substitution patterns in these genes. Statistical associations (higher rates for central nodes) or lack thereof (centrality of duplicated genes) were in contrast to some current evolutionary hypotheses, highlighting the need for more research on these topics.
基因表达谱在性别之间可能会发生显著变化，性别偏倚可能为性别偏倚基因的特定宏观进化动态做出贡献。然而，由于缺乏评估性别偏倚基因的同源性和功能同源性的研究，以及可能限制其进化潜力的多效性效应，这些动态在大进化尺度上理解得很差。在这里，我们探讨了与性别偏倚基因相关的宏观进化过程的相关性，包括重复和加速的进化速度。具体来说，我们检查了在精子发生过程中协调精子个体化的 44 个基因中的这些特征，这些基因具有无偏倚和性别偏倚的表达。我们在昆虫的广泛进化框架中研究了这些基因，特别关注甲虫（鞘翅目）。我们研究了从 119 种昆虫基因组中挖掘的数据，包括 6 种甲虫模型，以及另外 19 种甲虫转录组。对于物理上和/或遗传上相互作用的蛋白质子集，我们还分析了它们的网络结构如何影响基因进化的模式。收集的基因在重复状态、进化率和速率稳定性方面高度异质，但有统计学证据表明性别偏倚与更快的进化速度相关，这与理论预测一致。更快的速度也与这些基因中的时钟（昆虫氨基酸）和非时钟（甲虫核苷酸）替代模式相关。统计关联（中心节点的更高速度）或缺乏关联（重复基因的中心性）与一些当前的进化假设形成对比，突出了需要对这些主题进行更多的研究。
