Natural Variation in the Promoter of GSE5 Contributes to Grain Size Diversity in Rice
Natural Variation in the Promoter of GSE5 Contributes to Grain Size Diversity in Rice
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GSE5 启动子的自然变异有助于水稻粒度的多样性
DOI：
10.1016/j.molp.2017.03.009
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发表时间：
2017-05-01
期刊：
影响因子：
27.5
通讯作者：
Li, Yunhai
中科院分区：
文献类型：
--
作者：
Duan, Penggen;Xu, Jinsong;Li, Yunhai
自然遗传变异的利用极大地有助于作物重要农艺性状的改良。了解谷粒大小自然变异的遗传基础可以帮助育种者开发高产水稻品种。在本研究中，我们通过全基因组关联研究和功能分析相结合的方法，在控制水稻籽粒大小的qSW 5/GW 5位点上鉴定了一个以前未被识别的基因，命名为GSE 5。GSE 5编码一个具有IQ结构域的质膜相关蛋白，该蛋白与水稻钙调素蛋白OsCaM 1 -1相互作用。我们发现GSE 5功能的丧失导致宽而重的谷粒，而GSE 5的过表达导致窄的谷粒。我们发现GSE 5主要通过影响小穗壳中的细胞增殖来调节籽粒大小。根据GSE 5启动子区的缺失/插入类型，鉴定了栽培稻中GSE 5的3种主要单倍型（GSE 5、GSE 5（DEL 1 + IN 1）和GSE 5（DEL 2））。我们证明了在携带GSE 5 DEL 1 + IN 1单倍型的籼稻品种中的950-bp缺失（DEL 1）和在携带GSE 5 DEL 2单倍型的粳稻品种中的1212-bp缺失（DEL 2）与GSE 5的表达降低相关，导致宽粒。进一步的分析表明，野生稻种质包含所有三个单倍型的GSE 5，这表明存在于栽培稻中的GSE 5单倍型可能起源于不同的野生稻种质在水稻驯化。综上所述，我们的研究结果表明，以前未被识别的GSE 5基因在qSW 5/GW 5位点，这是广泛利用的水稻育种，控制籽粒大小，并揭示了GSE 5的启动子区域的自然变异有助于水稻籽粒大小的多样性。
The utilization of natural genetic variation greatly contributes to improvement of important agronomic traits in crops. Understanding the genetic basis for natural variation of grain size can help breeders develop high-yield rice varieties. In this study, we identify a previously unrecognized gene, named GSE5, in the qSW5/ GW5 locus controlling rice grain size by combining the genome-wide association study with functional analyses. GSE5 encodes a plasma membrane-associated protein with IQ domains, which interacts with the rice calmodulin protein, OsCaM1-1. We found that loss of GSE5 function caused wide and heavy grains, while overexpression of GSE5 resulted in narrow grains. We showed that GSE5 regulates grain size predominantly by influencing cell proliferation in spikelet hulls. Three major haplotypes of GSE5 (GSE5, GSE5(DEL1+ IN1), and GSE5(DEL2)) in cultivated rice were identified based on the deletion/insertion type in its promoter region. We demonstrated that a 950-bp deletion (DEL1) in indica varieties carrying the GSE5 DEL1+ IN1 haplotype and a 1212-bp deletion (DEL2) in japonica varieties carrying the GSE5 DEL2 haplotype associated with decreased expression of GSE5, resulting in wide grains. Further analyses indicate that wild rice accessions contain all three haplotypes of GSE5, suggesting that the GSE5 haplotypes present in cultivated rice are likely to have originated from different wild rice accessions during rice domestication. Taken together, our results indicate that the previously unrecognized GSE5 gene in the qSW5/GW5 locus, which is widely utilized by rice breeders, controls grain size, and reveal that natural variation in the promoter region of GSE5 contributes to grain size diversity in rice.