Arabidopsis bZIP68 Modulates Flowering Time Potentially with Chromatin and Stress-Responsive Regulators

In Arabidopsis thaliana, the physiological functions and regulatory network of the transcription factor bZIP68 remain poorly understood. To investigate its potential functions and regulome, we integrated multiple publicly available omics datasets, including protein-protein interaction and co-expression networks, transcriptomic data from bzip68 mutants, bZIP68 ChIP-seq data, and ChIP-seq/DAP-seq and transcriptomic datasets for candidate regulatory factors. These integrated analyses suggested that bZIP68 is involved in floral morphology, flowering regulation, and responses to abiotic stress. Notably, SWI3D, MINU2, and CAMTA1 were identified as highly probable components of the bZIP68 core regulome. Subsequent transcriptomic network analysis revealed their putative signaling cascades. To validate the predicted role of bZIP68 in flowering regulation, we analyzed five independent homozygous EMS mutant (HEM) lines. All five mutant lines exhibited altered flowering phenotypes compared to the wild type. In conclusion, this study establishes an integrative framework for identifying the bZIP68 regulatory network and uncovers its novel physiological role in modulating flowering.