OsMAPK3 Phosphorylates OsbHLH002/OsICE1 and Inhibits Its Ubiquitination to Activate OsTPP1 and Enhances Rice Chilling Tolerance
作 者：Zhang ZY, Li JH, Li F, Liu HH, Yang WS, Chong K*, Xu YY*
影响因子:9.174
刊物名称:Developmental Cell
出版年份:2017
卷:43期:6 页码:731–743.e5
文章摘要:Improvement of chilling tolerance is a major target in rice breeding. The signaling pathways regulating chilling consist of complex networks, including key transcription factors and their targets. However, it remains largely unknown how transcription factors are activated by chilling stress. Here, we report thatthe transcription factor OsbHLH002/OsICE1 is phosphorylated by OsMAPK3 under chilling stress. Theosbhlh002-1knockout mutant and antisense transgenic plants showed chilling hypersensitivity, whereasOsbHLH002-overexpressing plants exhibited enhanced chilling tolerance. OsbHLH002 can directly targetOsTPP1, which encodes a key enzyme for trehalose biosynthesis. OsMAPK3 interacts with OsbHLH002 to prevent its ubiquitination by the E3 ligase OsHOS1. Under chilling stress, active OsMAPK3 phosphorylates OsbHLH002, leading to accumulation of phospho-OsbHLH002, which promotesOsTPP1expression and increases trehalose content and resistance to chilling damage.Taken together, these results indicate that OsbHLH002 is phosphorylated by OsMAPK3, which enhances OsbHLH002 activation to its targetOsTPP1during chilling stress.