Université de Strasbourg, CNRS, GMGM UMR7156, Strasbourg, France.
CNRS UMR7258, INSERM U1068, Aix Marseille Université UM105, Institut Paoli-Calmettes, CRCM, Marseille, France.
PLoS Genet. 2024 Sep 26;20(9):e1011426. doi: 10.1371/journal.pgen.1011426. eCollection 2024 Sep.
Meiotic recombination is essential for the accurate chromosome segregation and the generation of genetic diversity through crossover and gene conversion events. Although this process has been studied extensively in a few selected model species, understanding how its properties vary across species remains limited. For instance, the ancestral ZMM pathway that generates interference-dependent crossovers has undergone multiple losses throughout evolution, suggesting variations in the regulation of crossover formation. In this context, we first characterized the meiotic recombination landscape and properties of the Kluyveromyces lactis budding yeast. We then conducted a comprehensive analysis of 29,151 recombination events (19, 212 COs and 9, 939 NCOs) spanning 577 meioses in the five budding yeast species Saccharomyces cerevisiae, Saccharomyces paradoxus, Lachancea kluyveri, Lachancea waltii and K. lactis. Eventually, we found that the Saccharomyces yeasts displayed higher recombination rates compared to the non-Saccharomyces yeasts. In addition, bona fide crossover interference and associated crossover homeostasis were detected in the Saccharomyces species only, adding L. kluyveri and K. lactis to the list of budding yeast species that lost crossover interference. Finally, recombination hotspots, although highly conserved within the Saccharomyces yeasts are not conserved beyond the Saccharomyces genus. Overall, these results highlight great variability in the recombination landscape and properties through budding yeasts evolution.
减数分裂重组对于准确的染色体分离和通过交叉和基因转换事件产生遗传多样性至关重要。尽管在少数几个选定的模式物种中对这个过程进行了广泛的研究，但对其在物种间的特性变化仍知之甚少。例如，产生依赖干扰的交叉的祖先 ZMM 途径在进化过程中经历了多次丢失，这表明交叉形成的调控存在差异。在这种情况下，我们首先描述了出芽酵母 Kluyveromyces lactis 的减数分裂重组景观和特性。然后，我们对来自五个出芽酵母物种 Saccharomyces cerevisiae、Saccharomyces paradoxus、Lachancea kluyveri、Lachancea waltii 和 K. lactis 的 577 次减数分裂中的 29,151 个重组事件（19 个 CO 和 9,939 个 NCO）进行了全面分析。最终，我们发现与非 Saccharomyces 酵母相比，Saccharomyces 酵母的重组率更高。此外，只有在 Saccharomyces 物种中检测到真正的交叉干扰和相关的交叉稳态，这使得 L. kluyveri 和 K. lactis 成为失去交叉干扰的出芽酵母物种的列表中的一员。最后，尽管在 Saccharomyces 酵母中高度保守，但重组热点在 Saccharomyces 属之外并不保守。总体而言，这些结果强调了出芽酵母进化过程中重组景观和特性的巨大可变性。
