Université Côte d'Azur, CNRS, INSERM, IRCAN, Nice, France.
Curr Opin Genet Dev. 2022 Dec;77:101980. doi: 10.1016/j.gde.2022.101980. Epub 2022 Sep 7.
Sterile hybrids are broadly considered evolutionary dead-ends because of their faulty sexual reproduction. While sterility in obligate sexual organisms is a clear constraint in perpetuating the species, some facultative sexual microbes such as yeasts can propagate asexually and maintain genome plasticity. Moreover, incomplete meiotic pathways in yeasts represent alternative routes to the standard meiosis that generates genetic combinations in the population and fuel adaptation. Here, we review how aborting meiosis promotes genome-wide allele shuffling in sterile Saccharomyces hybrids and describe approaches to identify evolved clones in a cell population. We further discuss possible implications of this process in generating phenotypic novelty and report cases of abortive meiosis across yeast species.
无菌杂种通常被认为是进化的死胡同，因为它们的有性繁殖存在缺陷。虽然在有性生物中，不育是物种延续的明显限制，但一些兼性有性微生物，如酵母，可以进行无性繁殖并保持基因组的可塑性。此外，酵母中不完全的减数分裂途径代表了标准减数分裂的替代途径，标准减数分裂在种群中产生遗传组合，并为适应提供动力。在这里，我们回顾了无菌酿酒酵母杂种中减数分裂的中止如何促进全基因组等位基因的重排，并描述了鉴定细胞群体中进化克隆的方法。我们进一步讨论了这个过程在产生表型新颖性方面的可能影响，并报告了酵母物种中减数分裂失败的情况。
