MiR319-targeted OsTCP21 and OsGAmyb regulate tillering and grain yield in rice

• 作者: Rongna Wang Xiuyan Yang Shuang Guo Zhaohui Wang Zhanhui Zhang Zhongming Fang
• 来源期刊: 植物学报（英文版）
• 年，卷（期）: 2021,（7）
• 所属期刊栏目: Cell and Developmental Biology
• 页码范围: 1260-1272
• 页数: 13页
• 语种: 英文

摘要

Multiple genes and microRNAs (miRNAs) im-prove grain yield by promoting tillering. MiR319s are known to regulate several aspects of plant development; however, whether miR319s are essential for tillering regulation remains unclear. Here, we report that miR319 is highly expressed in the basal part of rice plant at different devel-opment stages. The miR319 knockdown line Short Tandem Target Mimic 319 (STTM319) showed higher tiller bud length in seedlings under low nitrogen (N) condition and higher tiller bud number under high N condition compared with the miR319a-overexpression line. Through targets prediction, we identified OsTCP21 and OsGAmyb as downstream targets of miR319. Moreover, OsTCP21 and OsGAmyb over-expression lines and STTM319 had increased tiller bud length and biomass, whereas both were decreased in OsTCP21 and OsGAmyb knockout lines and OE319a. These data suggest that miR319 regulates rice tiller bud development and tillering through targeting OsTCP21 and Os-GAmyb. Notably, the tiller number and grain yield increased in STTM319 and overexpression lines of OsTCP21 and OsGAmyb but decreased in OE319a and knockout lines of OsTCP21 and OsGAmyb. Taken together, our findings indicate that miR319s negatively affect tiller number and grain yield by targeting OsTCP21 and OsGAmyb, revealing a novel function for miR319 in rice.