UDP-glucosyltransferase regulates grain size and abiotic stress tolerance associated with metabolic flux redirection in rice

作者：Nai‐Qian Dong, Yuwei Sun, Tao Guo, Chuanlin Shi, Yimin Zhang, Yi Kan, You-Huang Xiang, Zhang Hai, Yi‐Bing Yang, Yachao Li, Huai‐Yu Zhao, Hong‐Xiao Yu, Zi‐Qi Lu, Yong Wang, Wang‐Wei Ye, Jun‐Xiang Shan, Hong‐Xuan Lin · 发表于：Nature Communications · 年份：2020 · DOI：10.1038/s41467-020-16403-5 · 被引用次数：376 · 研究领域：Genetic Mapping and Diversity in Plants and Animals、Plant Gene Expression Analysis、GABA and Rice Research

Grain size is an important component trait of grain yield, which is frequently threatened by abiotic stress. However, little is known about how grain yield and abiotic stress tolerance are regulated. Here, we characterize GSA1, a quantitative trait locus (QTL) regulating grain size and abiotic stress tolerance associated with metabolic flux redirection. GSA1 encodes a UDP-glucosyltransferase, which exhibits glucosyltransferase activity toward flavonoids and monolignols. GSA1 regulates grain size by modulating cell proliferation and expansion, which are regulated by flavonoid-mediated auxin levels and related gene expression. GSA1 is required for the redirection of metabolic flux from lignin biosynthesis to flavonoid biosynthesis under abiotic stress and the accumulation of flavonoid glycosides, which protect rice against abiotic stress. GSA1 overexpression results in larger grains and enhanced abiotic stress tolerance. Our findings provide insights into the regulation of grain size and abiotic stress tolerance associated with metabolic flux redirection and a potential means to improve crops.