数字农科院2.0

Argonaute2 Enhances Grain Length And Salt Tolerance By Activating Big Grain3 To Modulate Cytokinin Distribution In Rice

文献类型： 外文期刊

作者： Yin, WC; Xiao, YH; Niu, M; Meng, WJ; Li, LL; Zhang, XX; Liu, DP; Zhang, GX; Qian, YW; Sun, ZT; Huang, RY; Wang, SP; Liu, CM; Chu, CC; Tong, HN

作者机构：

期刊名称： PLANT CELL

ISSN： 1040-4651

年卷期： 2020 年 32 卷 7 期

页码：

收录情况： JCR（2021版）

摘要： Optimizing cytokinin distribution patterns is a promising strategy for simultaneously enhancing grain yield, grain quality, and stress resistance in plants, as observed in ARGONAUTE2-overexpressing rice. Maintaining stable, high yields under fluctuating environmental conditions is a long-standing goal of crop improvement but is challenging due to internal trade-off mechanisms, which are poorly understood. Here, we identify ARGONAUTE2 (AGO2) as a candidate target for achieving this goal in rice (Oryza sativa). Overexpressing AGO2 led to a simultaneous increase in salt tolerance and grain length. These benefits were achieved via the activation of BIG GRAIN3 (BG3), encoding a purine permease potentially involved in cytokinin transport. AGO2 can become enriched on the BG3 locus and alter its histone methylation level, thus promoting BG3 expression. Cytokinin levels decreased in shoots but increased in roots of AGO2-overexpressing plants. While bg3 knockout mutants were hypersensitive to salt stress, plants overexpressing BG3 showed strong salt tolerance and large grains. The knockout of BG3 significantly reduced grain length and salt tolerance in AGO2-overexpressing plants. Both genes were transcriptionally suppressed by salt treatment. Salt treatment markedly increased cytokinin levels in roots but decreased them in shoots, resulting in a hormone distribution pattern similar to that in AGO2-overexpressing plants. These findings highlight the critical roles of the spatial distribution of cytokinins in both stress responses and grain development. Therefore, optimizing cytokinin distribution represents a promising strategy for improving both grain yield and stress tolerance in rice.

分类号：

  • 相关文献
作者其他论文 更多>>