Genome-wide identification of the HvSCAMP gene family in barley and functional characterization of the role of HvSCAMP1 in salt tolerance

Secretory carrier membrane proteins (SCAMPs) play crucial roles in membrane trafficking and vesicle cycling in eukaryotes; however, their functions in plants remain inadequately characterized. Through a genome-wide bioinformatics analysis, we identified seven HvSCAMP genes in barley (Hordeum vulgare L.). Phylogenetic analysis classified them into three distinct groups, with members within the same group sharing similar motif compositions and gene structures. Promoter analysis revealed that all HvSCAMP members contain methyl jasmonate-responsive elements, while the salicylic acid-responsive elements were exclusively present in HvSCAMP1 of Group 1. Collinearity analysis revealed evolutionary conservation between SCAMP genes in barley, rice, and Arabidopsis. The prediction of upstream regulators indicated that HvSCAMPs are modulated by stress-associated miRNAs and ERF family transcription factors. Expression profiling demonstrated that HvSCAMP1 was significantly induced under salt stress in a salt-tolerant barley genotype. Subcellular localization confirmed that HvSCAMP1 localizes to the plasma membrane. Heterologous expression of HvSCAMP1 enhanced salt stress tolerance in yeast. Furthermore, Arabidopsis lines overexpressing HvSCAMP1 exhibited superior growth under salt stress, which was associated with increased antioxidant enzyme activity, elevated accumulation of osmoprotectants, alleviated oxidative damage, and reduced leaf Na+ accumulation. This study provides the first systematic identification of the SCAMP gene family in barley and highlights the role of HvSCAMP1 in positively regulating salt tolerance, offering a valuable genetic resource for molecular breeding of stress-resistant barley.