The DC1 domain protein Vacuoleless Gametophytes positively regulates salt stress tolerance in Arabidopsis thaliana

Vacuoleless Gametophytes (VLG) is a DC1 domain-containing protein initially characterized as essential for the development of both female and male gametophytes in Arabidopsis thaliana. In addition, VLG regulates stamen development through the involvement in lignin and jasmonic acid biosynthesis pathways. In this work, we report that VLG is also involved in salt stress tolerance in A. thaliana. Under salt stress, VLG-knock-down plants exhibited reduced germination, root elongation, biomass accumulation, photosynthetic pigment content, along with diminished expression of key salt-responsive genes. Conversely, these plants accumulated higher anthocyanins, and reactive oxygen species (H2O2 and O2-) compared to wilt type, indicating impaired oxidative stress control. In contrast, VLG-overexpressing plants showed a salt stress resistant phenotype with enhanced biomass and increased expression of salt-responsive genes under saline conditions. Together, these findings uncover an unexpected role for VLG as a positive regulator of salt tolerance, expanding the functional scope of DC1 domain proteins beyond reproductive development and providing new insights into plant mechanisms of abiotic stress resilience.