The CDPK Gene Family in Mustard (Brassica juncea L.): Genome-Wide Identification and Expression Analysis under Cold Stress

The CDPK family genes play crucial roles in signal transduction pathways during plant development and stress response. In this study, we comprehensively analyzed the CDPK family genes in mustard (Brassica juncea L.), resulting in the identification of 101 genes (BjuCDPK1-101) located on chromosomes AA_Chr01 to BB_Chr08. RNA-seq analysis showed that most BjuCDPK genes were predominantly expressed in the root and flower bud, suggesting their organ-specific expression patterns. Furthermore, the expression levels of most BjuCDPK genes were significantly altered by cold stress. The promoter regions of BjuCDPK genes had abundant cis-acting elements related to hormones and stress. The interaction network analysis predicted that BjuCDPK proteins respond to abiotic stress probably via interaction with ABF1, ABF4, and/or DI19. Our findings provide valuable information for further the investigation of the cold stress adaption of mustard via the CDPK signaling pathway.