Genome‐Wide Identification and Stress‐Responsive Expression of the JAZ Gene Family in Cinnamomum burmannii

ABSTRACT

JASMONATE ZIM‐DOMAIN (JAZ) proteins act as central repressors of jasmonate signaling, modulating plant development, stress resilience, and secondary metabolism. Despite the economic and ecological importance of the aromatic tree Cinnamomum burmannii , its JAZ family has not been systematically explored. We performed a genome‐wide survey and identified 12 CbJAZ genes, all harboring conserved TIFY and Jas domains and unevenly distributed across seven chromosomes. Phylogenetic reconstruction assigned them to four clades, each exhibiting conserved exon–intron structures and motif compositions. Segmental duplication events primarily drove the expansion of this family. Promoter cis ‐element analysis revealed a rich repertoire of hormone‐, light‐, and stress‐responsive motifs. Tissue‐specific expression profiling showed that most CbJAZ transcripts accumulate preferentially in flowers and fruits. Upon exogenous methyl jasmonate (MeJA) treatment, the majority of CbJAZ genes were significantly induced, whereas abscisic acid (ABA) and drought stress generally suppressed their expression. Notably, CbJAZ8 and CbJAZ9 emerged as robust responders to all three treatments, and their encoded proteins localized to the nucleus, implicating them as candidate genes for future investigation of JA, ABA, and drought signaling crosstalk and potential regulators of essential oil biosynthesis. This first comprehensive characterization of the CbJAZ family not only furnishes a valuable genetic resource but also pinpoints CbJAZ8 and CbJAZ9 as prime candidates for future investigations into JA‐mediated stress adaptation and essential oil regulation in this economically relevant tree species.