CarNAC2, a novel NAC transcription factor in chickpea (Cicer arietinum L.), is associated with drought-response and various developmental processes in transgenic Arabidopsis.

摘要

As a large family of regulatory proteins, NAC (for NAM, ATAF1,2 and CUC2) proteins play important roles in various plant developmental processes and response to environmental stresses. Several studies have investigated the role of NAC transcription factors during these processes. In the present study, a gene encoding a NAC protein from chickpea (Cicer arietinum L.), CarNAC2, which encodes a putative protein of 191 amino acids, was isolated and characterized. Analyses of mRNA levels revealed that the expression of CarNAC2 was up-regulated by drought and ABA (abscisic acid). CarNAC2::GFP fusion protein was localized in the nucleus. Yeast one-hybrid assay showed that CarNAC2 possesses transcriptional activation activity which was located in the C-terminal region. Overexpression of CarNAC2 enhanced drought tolerance in transgenic Arabidopsis plants. In addition, transgenic plant overexpressing CarNAC2 displayed lower germination vigor and later blooming than wild type plants. Overall, our findings suggest that CarNAC2 protein as a transcriptional activator is involved in response to drought stress and various developmental processes in chickpea.