Abstract:
Recent advances in DNA sequencing technology have enabled the precise decoding of genomes in non-model organisms, providing a basis for unraveling the patterns and mechanisms of sex chromosome evolution. Studies of different species have yielded conflicting results regarding the traditional theory that sex chromosomes evolve from autosomes via the accumulation of deleterious mutations and degeneration of the Y (or W) chromosome. The concept of the \'sex chromosome cycle,\' emerging from this context, posits that at any stage of the cycle (i.e., differentiation, degeneration, or loss), sex chromosome turnover can occur while maintaining stable sex determination. Thus, understanding the mechanisms that drive both the persistence and turnover of sex chromosomes at each stage of the cycle is crucial. In this review, we integrate recent findings on the mechanisms underlying maintenance and turnover, with a special focus on several organisms having unique sex chromosomes. Our review suggests that the diversity of sex chromosomes in the maintenance of stable sex determination is underappreciated and emphasizes the need for more research on the sex chromosome cycle.
摘要:
DNA测序技术的最新进展使非模型生物的基因组能够精确解码,为揭示性染色体进化的模式和机制提供依据。关于性染色体通过Y(或W)染色体的有害突变的积累和变性从常染色体进化而来的传统理论,对不同物种的研究产生了相互矛盾的结果。性染色体周期的概念,\'从这个上下文中出现,假定在周期的任何阶段(即,分化,变性,或损失),性染色体周转可以在保持稳定的性别决定的同时发生。因此,了解在周期的每个阶段驱动性染色体的持久性和周转的机制至关重要。在这次审查中,我们整合了最近关于维护和周转机制的调查结果,特别关注几种具有独特性染色体的生物。我们的评论表明,在维持稳定的性别决定中,性染色体的多样性被低估了,并强调需要对性染色体周期进行更多研究。