Single cis-elements in brassinosteroid-induced upregulated genes are insufficient to recruit both redox states of the BIL1/BZR1 DNA-binding domain.

ABSTRACT: The plant-specific transcription factor BRZ-INSENSITIVE-LONG 1 (BIL1)/BRASSINAZOLE-RESISTANT 1 (BZR1) regulates the growth of Arabidopsis thaliana via brassinosteroid signaling, acting as both a gene repressor and activator. Its upregulation requires environmental cues mediated by PHYTOCHROME INTERACTING FACTOR 4 (PIF4), with oxidative modifications via H₂O₂ enhancing their interaction. However, the nature of the tripartite complex of cis-elements, BIL1/BZR1, and PIF4 under redox changes remains unclear. Here, we demonstrate that oxidation of the DNA-binding domain (DBD) of BIL1/BZR1 alters its DNA-binding ability. However, single cis-elements enriched in brassinosteroid-induced genes do not support binding of either redox form, nor does BIL1/BZR1 DBD heterodimerize w

SUBMITTER: Nosaki S 

PROVIDER: S-EPMC12668046 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature