Plasma membrane‐localized Hsp40/DNAJ chaperone protein facilitates OsSUVH7‐OsBAG4‐OsMYB106 transcriptional complex formation for OsHKT1;5 activation

作者：Yutong Liu, Mengting Li, Jinlei Yu, Ao Ma, Jie Wang, Dae‐Jin Yun, Zheng‐Yi Xu · 发表于：Journal of Integrative Plant Biology · 年份：2022 · DOI：10.1111/jipb.13403 · 被引用次数：31 · 研究领域：Heat shock proteins research、Plant Stress Responses and Tolerance、Plant Genetic and Mutation Studies

) transport is a key salt tolerance mechanism during rice growth and development. Using a previously generated high-throughput activation tagging-based T-DNA insertion mutant pool, we isolated a mutant exhibiting salt stress-sensitive phenotype, caused by a reduction in OsHKT1;5 transcripts. The salt stress-sensitive phenotype of this mutant results from the loss of function of OsDNAJ15, which encodes plasma membrane-localized heat shock protein 40 (Hsp40). osdnaj15 loss-of-function mutants show decreased plant height, increased leaf angle, and reduced grain number caused by shorter panicle length and fewer branches. On the other h'and, OsDNAJ15-overexpression plants showed salt stress-tolerant phenotypes. Intriguingly, salt stress facilitates the nuclear relocation of OsDNAJ15 so that it can interact with OsBAG4, and OsDNAJ15 and OsBAG4 synergistically facilitate the DNA-binding activity of OsMYB106 to positively regulate the expression of OsHKT1;5. Overall, our results reveal a novel function of plasma membrane-localized Hsp40 protein in modulating, alongside chaperon regulator OsBAG4, transcriptional regulation under salinity stress tolerance.