An asymmetric allelic interaction drives allele transmission bias in interspecific rice hybrids
An asymmetric allelic interaction drives allele transmission bias in interspecific rice hybrids
复制标题
不对称等位基因相互作用驱动种间水稻杂交种等位基因传递偏差
DOI：
10.1038/s41467-019-10488-3
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发表时间：
2019-06-07
影响因子：
16.6
通讯作者：
Chen, Letian
中科院分区：
文献类型：
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作者：
Xie, Yongyao;Tang, Jintao;Chen, Letian
亚洲栽培稻（Oryza sativa）和非洲栽培稻（O. glaberrima）之间的杂种不育（HS）主要由S1位点控制。然而，我们对杂种不育机制的有限了解阻碍了强大的种间杂种优势的利用。在此，我们表明非洲S1等位基因（S1 - g）中的三个紧密连锁的基因（S1A4、S1TPR和S1A6）构成了一个杀手 - 保护者系统，该系统会消除携带亚洲等位基因（S1 - s）的配子。在亚非水稻杂种（S1 - gS1 - s）中，孢子体组织中的S1TPR - S1A4 - S1A6相互作用会对雌雄配子产生败育信号。然而，S1TPR能够拯救S1 - g配子，而S1 - s配子因缺乏S1TPR而选择性败育。敲除任何一个S1 - g基因都会消除杂种不育。进化分析表明，S1可能源自新进化的基因、多步重组和核苷酸变异。我们的研究结果将有助于克服种间生殖障碍，并利用亚非杂种来提高水稻产量。
Hybrid sterility (HS) between Oryza sativa (Asian rice) and O. glaberrima (African rice) is mainly controlled by the S1 locus. However, our limited understanding of the HS mechanism hampers utilization of the strong interspecific heterosis. Here, we show that three closely linked genes (S1A4, S1TPR, and S1A6) in the African S1 allele (S1-g) constitute a killer-protector system that eliminates gametes carrying the Asian allele (S1-s). In Asian-African rice hybrids (S1-gS1-s), the S1TPR-S1A4-S1A6 interaction in sporophytic tissues generates an abortion signal to male and female gametes. However, S1TPR can rescue S1-g gametes, while the S1-s gametes selectively abort for lacking S1TPR. Knockout of any of the S1-g genes eliminates the HS. Evolutionary analysis suggests that S1 may have arisen from newly evolved genes, multi-step recombination, and nucleotide variations. Our findings will help to overcome the interspecific reproductive barrier and use Asian-African hybrids for increasing rice production.