Abstract
Jasmonate-ZIM domain (JAZ) proteins act as repressors in the jasmonic acid (JA) signaling pathway and also function as plant-specific proteins participating in plant growth and development, stress response, and defense. In our study, a total of 25 JAZ genes were identified in B. rapa based on their conserved domains. First, the primary characteristics were surveyed, including the lengths of the CDS and proteins, molecular weights, and isoelectric points. Next, a phylogenetic tree of JAZ proteins among B. rapa, A. thaliana, O. sativa, B. oleracea, and B. napus was constructed, which revealed that these proteins cluster into four groups based on sequence homology rather than by species. Synteny analysis of JAZ genes among these species demonstrated that the highest number of collinear pairs was found between B. rapa and B. napus. Most BrJAZ genes were highly expressed in root, stem, and leaf. Moreover, the expression levels of BrJAZ1a and BrJAZ6b were induced by drought, high salt, black rot, and MeJA. Over-expressed these genes in A. thaliana lines enhanced their tolerance to drought and high salt stress, which was associated with higher enzymatic activities of SOD and POD. Both BrJAZ1a-GFP and BrJAZ6b-GFP were localized in the nucleus.