National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China.
Nat Commun. 2019 Feb 15;10(1):785. doi: 10.1038/s41467-019-08786-x.
Meiotic crossover (CO) plays a key role in producing gametophytes and generating genetic variation. The patterns of CO production differ inter- and intra-species, as well as between sexes. However, sex-specific patterns of CO production have not been accurately profiled independently of genetic backgrounds in maize. Here, we develop a method to isolate single female gametophyte for genomes sequencing in maize. We show that more COs are observed in male (19.3 per microspore) than in female (12.4 per embryo sac). Based on Beam-Film model, the more designated class I and II COs are identified in male than in female. In addition, CO maturation inefficiency (CMI) is detected in some genetic backgrounds, suggesting that maize may be an ideal model for dissecting CMI. This research provides insights toward understanding the molecular mechanism of CO production between sexes and may help to improve maize breeding efficiency through paternal selection.
减数分裂交叉（CO）在产生配子体和产生遗传变异方面起着关键作用。CO 的产生模式在种间和种内以及性别之间存在差异。然而，在玉米中，尚未独立于遗传背景准确地描绘出性别特异性的 CO 产生模式。在这里，我们开发了一种方法来分离玉米中的单个雌性配子体进行基因组测序。我们发现，雄性（每个花粉粒 19.3 个）中的 CO 比雌性（每个胚囊 12.4 个）中观察到的更多。基于 Beam-Film 模型，在雄性中鉴定出比雌性更多的指定类 I 和 II CO。此外，在一些遗传背景中检测到 CO 成熟效率低下（CMI），这表明玉米可能是解析 CMI 的理想模型。这项研究为理解性别间 CO 产生的分子机制提供了新的思路，并可能有助于通过父本选择提高玉米的育种效率。
