The transcriptional hub SHORT INTERNODES1 integrates hormone signals to orchestrate rice growth and development

• DOI: 10.1093/plcell/koad130
• Publication Date: 2023-05-17T16:39:19Z
• Authors: Erchao Duan; Qibing Lin; Yihua Wang; Yulong Ren; Huan Xu; Yuanyan Zhang; Yunlong Wang; Xuan Teng; Hui Dong; Yupeng Wang; Xiaokang Jiang; Xiaoli Chen; Jie Lei; Hang Yang; Rongbo Chen; Ling Jiang; Haiyang Wang; Jianmin Wan
• Keywords: Brassinosteroid; Crosstalk; Inducer; Plant hormone

Abstract Plants have evolved sophisticated mechanisms to coordinate their growth and stress responses via integrating various phytohormone signaling pathways. However, the precise molecular orchestrating integration of pathways remain largely obscure. In this study, we found that rice (Oryza sativa) short internodes1 (shi1) mutant exhibits typical auxin-deficient root development gravitropic response, brassinosteroid (BR)-deficient plant architecture grain size as well enhanced abscisic acid (ABA)-mediated drought tolerance. Additionally, shi1 is also hyposensitive auxin BR treatment but hypersensitive ABA. Further, showed OsSHI1 promotes biosynthesis by activating expression OsYUCCAs D11, meanwhile dampens ABA inducing OsNAC2, which encodes a repressor signaling. Furthermore, demonstrated 3 classes transcription factors, AUXIN RESPONSE FACTOR 19 (OsARF19), LEAF AND TILLER ANGLE INCREASED CONTROLLER (LIC), OsZIP26 OsZIP86, directly bind promoter regulate its in response auxin, BR, ABA, respectively. Collectively, our results unravel an OsSHI1-centered transcriptional regulatory hub orchestrates self-feedback regulation multiple adaptation.