Identification and expression analysis of C2H2-zinc finger protein genes reveals their role in stress tolerance in Brassica napus

C2H2-zinc finger (C2H2-ZF) genes are involved in various biological processes in plants including stress response; however, they lack characterization in Brassica napus. We identified 267 C2H2-ZF genes in B. napus and deciphered their physiological properties, subcellular localization, structure, synteny, and phylogeny and investigated the expression of 20 genes in response to different stresses and phytohormone treatments. The 267 genes were distributed on 19 chromosomes; phylogenetic analysis categorized them into five clades. They varied from 0.41 to 9.2 kb in length, had stress-responsive cis-acting elements in promoter regions, and their protein length varied from 9 to 1366 amino acids. About 42% of the genes had one exon, and 88% genes had orthologs in Arabidopsis thaliana. About 97% of the genes were located in nucleus and 3% in cytoplasmic organelles. qRT-PCR analysis showed a different expression pattern of these genes in response to biotic stresses (Plasmodiophora brassicae and Sclerotinia sclerotiorum) and abiotic stresses (cold, drought, and salinity) and hormonal treatments. Differential expression of the same gene was observed under multiple stress conditions, and a few genes showed similar expression in response to more than one phytohormones. Our results suggest that the C2H2-ZF genes can be targeted for the improvement of stress tolerance in canola.