Genome-Wide Identification and Expression Analysis of TaDES1 Gene Family Responded to Biotic and Abiotic Stress in Wheat (Triticum aestivum L.)

L-Cysteine desulfhydrase (DES1), a key enzyme in eukaryotes, catalyzes the synthesis of hydrogen sulfide (H₂S), which is a gaseous signaling molecule. However, the genes encoding DES1 enzymes in wheat, one of the world's most important crop species, have yet to be fully characterized. This study offers a comprehensive analysis of the wheat TaDES1 gene family and delves into its potential functions. We identified a total of 18 TaDES1 genes, located across 13 chromosomes, categorized them into four subfamilies, and comprehensively analyzed their physicochemical properties. Furthermore, three DES1 gene families (HvDES1, OsDES1, and ZmDES1) were identified in three Poaceae species to explore the evolutionary relationships of TaDES1 and its homologs. The results indicated that segmental duplication drove the expansion of the TaDES1 family, which experienced strong purifying selection. Promoter cis-elements and gene ontology (GO) enrichment analysis revealed the significant roles of this gene in the stress response, phytohormone regulation, and plant growth. miRNA target prediction analysis further explored the regulatory relationships. Transcriptomic data revealed that TaDES1 members are responsive to abiotic stresses, biotic stresses, and exogenous abscisic acid (ABA) treatment. The qPCR (RT–qPCR) results also demonstrated that the TaDES1 gene is responsive to multiple stresses. Co-expression network analysis emphasized the importance of key TaDES1 genes in stress responses. Finally, simple sequence repeats (SSRs) within the TaDES1 family were predicted, and variation analysis of three key TaDES1 genes and their homologs across ten wheat cultivars was performed to explore their potential in wheat breeding.