Identification and Expression Characteristics of the vacuolar H+ pyrophosphatase Gene Family form Beta vulgaris L.

The vacuole-type H ⁺ -pyrophosphatase (H ⁺ -PPase) are major proton pumps in the vacuolar membrane. They regulate plant growth, development, and responses to abiotic stress. Despite their importance, research on H ⁺ -PPase in sugar beet remains limited. In this study, the BvVPs family in sugar beet was identified and characterized for the first time. 6 genes were identified through bioinformatic analysis and classified into 4 subfamilies. Members of the same subfamily showed conserved gene structures, domains, and motifs. Chromosomal mapping showed that these genes were unevenly distributed across 4 chromosomes. Analysis of cis-acting elements suggested that the BvVPs family were involved in sugar beet growth, development, and stress responses. RNA-seq and qRT-PCR analyses showed that members of the BvVPs family respond differently to salt stress. Among these genes, BvVP4 displayed the highest transcript levels and remained consistently abundant in leaves. Functional assays in Arabidopsis thaliana , including overexpression and complementation, confirmed that BvVP4 contributes to enhanced salt tolerance. Specifically, its expression improved germination under salt stress and supported root growth and development in seedlings.Identification and Expression Characteristics of the vacuolar H ⁺ pyrophosphatase Gene Family form Beta vulgaris L.