New Phytologist. doi: 10.1111/nph.16670

Jun Miao, Xianfeng Li, Xiangbo Li, Wenchen Tan, Aiqing You, Shujun Wu, Yajun Tao, Chen Chen, Jun Wang, Dongping Zhang, Zhiyun Gong, Chuandeng Yi, Zefeng Yang, Minghong Gu, Guohua Liang* and Yong Zhou*

Abstract

Plants maintain a dynamic balance between plant growth and stress tolerance to optimize their fitness and ensure survival. Here, we investigated the roles of a clade A type 2C protein phosphatase (PP2C)-encoding gene, OsPP2C09, in regulating the trade-off between plant growth and drought tolerance in rice (Oryza sativa). The OsPP2C09 protein interacted with the core components of abscisic acid (ABA) signaling and showed PP2C phosphatase activity in vitro. OsPP2C09 positively affected plant growth but acted as a negative regulator of drought tolerance through ABA signaling. The transcript and protein levels of OsPP2C09 were rapidly induced by exogenous ABA treatments, which suppressed excessive ABA signaling and plant growth arrest. OsPP2C09 transcript levels in roots were much higher than those in shoots under normal conditions. After ABA, polyethylene glycol, and dehydration treatments, the accumulation rate of OsPP2C09 transcripts in roots was more rapid and greater than that in shoots. This differential expression between the roots and shoots may increase the plant's root-to-shoot ratio under drought-stress conditions. This study shed new light on the roles of OsPP2C09 in coordinating plant growth and drought tolerance. In particular, we proposed that OsPP2C09-mediated ABA desensitization contributes to root elongation under drought-stress conditions in rice.

全文链接：

https://nph.onlinelibrary.wiley.com/doi/epdf/10.1111/nph.16670