Abstract
Identification of seed development regulatory genes is the key for the genetic improvement in rice grain quality. NF‐Ys are the important transcription factors, but their roles in rice grain quality control and the underlying molecular mechanism remain largely unknown. Here, we report the functional characterization a rice NF‐Y heterotrimer complex NF‐YB1‐YC12‐bHLH144, which is formed by the binding of NF‐YB1 to NF‐YC12 and then bHLH144 in a sequential order. Knock‐out of each of the complex genes resulted in alteration of grain qualities in all the mutants as well as reduced grain size in crnf‐yb1 and crnf‐yc12. RNA‐seq analysis identified 1496 genes that were commonly regulated by NF‐YB1 and NF‐YC12, including the key granule‐bound starch synthase gene Wx. NF‐YC12 and bHLH144 maintain NF‐YB1 stability from the degradation mediated by ubiquitin/26S proteasome, while NF‐YB1 directly binds to the ‘G‐box’ domain of Wx promoter and activates Wx transcription, hence to regulate rice grain quality. Finally, we revealed a novel grain quality regulatory pathway controlled by NF‐YB1‐YC12‐bHLH144 complex, which has great potential for rice genetic improvement.
Copyright ? 2003-2019 China National Rice Research Institute. 中国水稻研究所 版权所有
地址：杭州市富阳区水稻所路28号（邮政编码：311401）电话：+86 571 63370590
杭州市拱墅区体育场路359号（邮政编码：310006）
京ICP备10039560号-5 浙公网安备33010302000429号
技术支持：中国农业科学院农业信息研究所