Genome-Wide Identification of the PsatGST Gene Family and Expression Analysis Under Freezing Stress in Peas (Pisum sativum L.).

BACKGROUND

Glutathione S-transferases (GSTs) play pivotal roles in plant growth, abiotic stress responses, detoxification of xenobiotics, and maintenance of redox homeostasis.

METHODS

In this study, transcriptomic analysis was employed to identify differentially expressed genes (DEGs) in the pea cultivar DX27 under freezing stress (-4 °C) at 3, 6, and 12 h.

RESULTS

GO and KEGG enrichment analyses of global transcriptomic data further reveal that DEGs are significantly enriched in the following functional categories: oxidation-reduction processes, stress responses, glutathione metabolism, and secondary metabolite biosynthesis. A total of 52 PsatGST genes were identified and classified into nine subfamilies based on phylogenetic relationships. Chromosomal localization revealed a non-random distribution across seven chromosomes. Promoter cis-element analysis indicated that PsatGST genes harbor diverse regulatory elements associated with light responsiveness, hormone signaling (auxin, abscisic acid, gibberellin, salicylic acid, and MeJA), and abiotic/biotic stress responses. PsatGSTF2 expression analysis showed pronounced up-regulation under freezing stress (-4 °C) at 3, 6, and 12 h.

CONCLUSIONS

These findings provide a foundational framework for understanding the evolutionary history and functional diversification of the PsatGST gene family and offer valuable candidate genes for the breeding of stress-tolerant pea varieties.