Molecular mechanisms underpinning the multiallelic inheritance ofMS5inBrassica napus
Molecular mechanisms underpinning the multiallelic inheritance ofMS5inBrassica napus
复制标题
甘蓝型油菜MS5多等位基因遗传的分子机制
DOI：
10.1111/tpj.14857
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发表时间：
2020
期刊：
影响因子：
7.2
通讯作者：
Hong Dengfeng
中科院分区：
文献类型：
--
作者：
Xin Qiang;Wang Xiang;Gao Yupeng;Xu Dongdong;Xie Zhaoqi;Dong Faming;Wan Lili;Yang Liyong;Yang Guangsheng;Hong Dengfeng
芸苔属特异基因MS5介导早期减数分裂进程，其等位变异体有助于油菜（Brassica napusL.）核雄性不育三系杂交生产系统。然而，其三等位基因遗传的潜在机制知之甚少。结果表明，恢复等位基因MS 5a和保持等位基因MS 5care均为甘蓝型油菜雄性育性所必需。MS5a和MS5cis的功能差异与其编码区的序列变异密切相关，而与其启动子区的关系不太密切。雄性不育等位基因MS5 bencode一种嵌合蛋白，仅含有完整的MS5卷曲螺旋（CC）结构域，失去了MS5超家族结构域。MS 5a和MS 5c都可以通过CC结构域在细胞核中形成同源二聚体。MS5b可以与MS5a或MS5c竞争性相互作用，形成非功能性异源二聚体。由于MS5和MS5cinMS5bMS5c的转录水平接近，这些异二聚体诱导了MS5bonMS5c的显性负效应，导致雄性不育表型。MS 5a的极高转录丰度在MS 5a MS 5b中维持了足够的MS 5a同源二聚体，导致雄性不育的恢复。这些发现提供了大量的遗传和分子证据，以提高我们对MS 5多等位基因遗传机制的理解，并为在植物物种中改进MS 5控制的GMS系统的使用奠定了坚实的基础。
TheBrassica‐specific geneMS5mediates early meiotic progression, and its allelic variants contribute to a valuable genic male sterility three‐line hybrid production system in rapeseed (Brassica napusL.). However, the underlying mechanisms of its triallelic inheritance are poorly understood. Herein, we show that the restorer alleleMS5aand the maintainer alleleMS5care both necessary for male fertility inB. napus. The functional divergence ofMS5aandMS5cis strongly related to sequence variations in their coding regions and less strongly to their promoter regions. The male‐sterile alleleMS5bencodes a chimeric protein containing only the complete MS5 coiled‐coil (CC) domain, having lost the MS5 superfamily domain. Both MS5aand MS5ccan form homodimers in the nucleus via the CC domain. MS5bcan interact competitively with MS5aor MS5cto form non‐functional heterodimers. Owing to the close transcript levels ofMS5bandMS5cinMS5bMS5c, these heterodimers induced a dominant‐negative effect ofMS5bonMS5c,resulting in a male‐sterile phenotype. The extremely high transcript abundance ofMS5amaintains sufficient MS5ahomodimers inMS5aMS5b, causing the recovery of male sterility. These findings provide substantial genetic and molecular evidence to improve our understanding of the mechanisms underlying the multiallelic inheritance ofMS5, and enable the construction of a solid foundation for improved use of theMS5‐controlled GMS system inBrassicaspecies.