Abstract
Abscisic acid (ABA), a pivotal phytohormone regulating plant growth and stress adaptation, orchestrates abiotic stress responses through the ABA-responsive element-binding factors ABF/AREB/ABI5. Nevertheless, the functional characterization of ABF/AREB/ABI5 homologs in Z. jujuba cv. Dongzao remains unexplored. In this study, we identified seven ZjABF genes distributed across five chromosomes. Domain analyses revealed high structural conservation, particularly within the basic leucine zipper (bZIP) DNA-binding domain. Subcellular localization confirmed nuclear targeting of all seven ZjABF proteins. Phylogenetic classification resolved these factors into three clades (A-C). Cis-regulatory element profiling implicated the involvement of the ZjABFs in hormone signaling, abiotic stress transduction, and photoregulatory pathways. Synteny analyses identified three segmental duplication events within the gene family. Tissue-specific expression patterns indicated critical roles for ZjABF2 and ZjABF3 in fruit maturation, and most of the ABF/AREB/ABI5 genes were highly expressed in the root. Under drought stress, four ZjABF genes exhibited differential expression, with ZjABF2 demonstrating pronounced sensitivity. These findings establish a molecular framework for understanding ZjABF-mediated abiotic stress responses in non-model woody perennials.