Differential expression of GS5 regulates grain size in rice.
Differential expression of GS5 regulates grain size in rice.
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GS5的差异表达调节水稻的籽粒大小
DOI：
10.1093/jxb/erv058
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发表时间：
2015-05
影响因子：
6.9
通讯作者：
Zhang Q
中科院分区：
文献类型：
--
作者：
Xu C;Liu Y;Li Y;Xu X;Xu C;Li X;Xiao J;Zhang Q
GS 5基因启动子区的两个SNPs负责控制晶粒大小的表达变异。GS 5的增强表达竞争性抑制OsBAK 1和OsMSBP 1之间的相互作用，促进晶粒尺寸。粒重是决定粮食产量的主要因素。GS 5是一个正向的籽粒大小调节因子，其表达水平与粒宽、灌浆和粒重相关。以前的工作表明，GS 5基因启动子区的多态性可能是导致晶粒大小变化的原因。在这项研究中，两个单核苷酸多态性（SNPs）之间的宽粒等位基因GS 5 -1和窄粒等位基因GS 5 -2的上游区域的基因，负责在发育中的幼穗的差异表达的鉴定。这两种多态性改变了GS 5等位基因对脱落酸（阿坝）处理的反应，导致GS 5 -1在发育中的幼穗中的表达高于GS 5 -2。研究还表明，启动子的光响应元件中的SNP改变了对光诱导的响应，导致叶片中GS 5 -2的表达高于GS 5 -1。GS 5的表达增强通过占据OsBAK 1 -7的胞外富含亮氨酸重复序列（LRR）结构域竞争性抑制OsBAK 1 -7与OsMSBP 1的相互作用，从而阻止OsBAK 1 - 7与OsMSBP 1相互作用引起的内吞作用，为GS 5表达与晶粒大小之间的正相关提供了解释。这些结果推进了我们对GS 5控制晶粒大小的分子机制的理解。
Two SNPs in the promoter of GS5 are responsible for expression variation controlling grain size. Enhanced expression of GS5 competitively inhibits the interaction between OsBAK1 and OsMSBP1, promoting grain size. Grain weight is a major determinant of grain yield. GS5 is a positive regulator of grain size such that grain width, filling, and weight are correlated with its expression level. Previous work suggested that polymorphisms of GS5 in the promoter region might be responsible for the variation in grain size. In this study, two single nucleotide polymorphisms (SNPs) between the wide-grain allele GS5-1 and the narrow-grain allele GS5-2 in the upstream region of the gene that were responsible for the differential expression in developing young panicles were identified. These two polymorphs altered the responses of the GS5 alleles to abscisic acid (ABA) treatments, resulting in higher expression of GS5-1 than of GS5-2 in developing young panicles. It was also shown that SNPs in light-responsive elements of the promoter altered the response to light induction, leading to higher expression of GS5-2 than GS5-1 in leaves. Enhanced expression of GS5 competitively inhibits the interaction between OsBAK1-7 and OsMSBP1 by occupying the extracellular leucine-rich repeat (LRR) domain of OsBAK1-7, thus preventing OsBAK1-7 from endocytosis caused by interacting with OsMSBP1, providing an explanation for the positive association between grain size and GS5 expression. These results advanced our understanding of the molecular mechanism by which GS5 controls grain size.