BAK1 plays contrasting roles in regulating abscisic acid‐induced stomatal closure and abscisic acid‐inhibited primary root growth in Arabidopsis

• DOI: 10.1111/jipb.13257
• Publication Date: 2022-03-30T02:28:36Z
• Authors: Jinping Deng; Lingyao Kong; Yinhua Zhu; Dan Pei; Xuexue Chen; Yu Wang; Junsheng Qi; Chunpeng Song; Shuhua Yang; Zhizhong Gong
• Keywords: Brassinosteroid; Wild type

The mechanisms that balance plant growth and stress responses are poorly understood, but they appear to involve abscisic acid (ABA) signaling mediated by protein kinases. Here, explore these mechanisms, we examined the of Arabidopsis thaliana kinase mutants ABA treatment. We found BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED RECEPTOR KINASE 1 (BAK1) were hypersensitive effects on both seed germination primary root growth. OPEN STOMATA (OST1) was more highly activated in bak1 mutant than wild type. BAK1 not treatment dominant negative abi1-1 or pyr1 pyl4 pyl5 pyl8 quadruple mutant, it this abi1-2 abi2-2 hab1-1 loss-of-function triple phosphorylates OST1 T146 inhibits its activity. Genetic analyses suggested acts at upstream core components pathway, including PYLs, PP2Cs, SnRK2s, during Although brassinosteroid (BR) BR (BRI1) positively regulate ABA-induced stomatal closure, mutations affecting downstream signaling, BRASSINOSTEROID-SIGNALING KINASEs (BSKs) BRASSINOSTEROID-INSENSITIVE 2 (BIN2), did affect ABA-mediated movement. Thus, our study uncovered an important role negatively regulating growth, modulating thus optimizing under drought stress.