Genome-wide analysis of glutathione S-transferase gene family in chickpea suggests its role during seed development and abiotic stress.

Glutathione S-transferases (GSTs) are multifunctional proteins that help in oxidative stress metabolism and detoxification of xenobiotic compounds. Studies pertaining to GST gene family have been undertaken in various plant species, however no information is available with respect to GST genes in chickpea. In the current study, we identified a total of 51 GST encoding genes in chickpea (CaGST) genome. Phylogenetic analysis revealed that GST gene family can be divided into eleven distinct classes. Tau and phi were the major classes in chickpea and one third of the CaGST genes represented segmental duplication and purifying selection was common among these genes. Expression of many CaGST genes, in particular, members of tau class were found to be upregulated under abiotic stress conditions. In addition, CaGST genes displayed differential expression patterns across diverse organs/tissues, suggesting their roles in developmental processes. Many CaGST genes showed opposite expression pattern in small- and large-seeded chickpea cultivars during seed development. Higher expression of CaGST genes in small-seeded cultivar at maturation stages of seed development suggested their important role in seed development and seed size/weight determination in chickpea. Overall, these results provide a comprehensive information on GST gene family members in chickpea and is expected to provide a rational platform to explore versatile role of these genes in semi-arid legume crops.