Fuente: PubMed "Tomato process" Plant Sci. 2026 Jun 12;371:113273. doi: 10.1016/j.plantsci.2026.113273. Online ahead of print.ABSTRACTRho-like GTPases of plants (ROPs) regulate diverse cellular processes, but their roles in tomato drought responses are largely unknown. In this study, nine ROP genes were identified in tomato (Solanum lycopersicum). Among them, SlROP4, the sole tomato ortholog of Arabidopsis AtROP6, was highly expressed, localized to the plasma membrane, and induced by drought stress. Transgenic tomato plants expressing a dominant-negative form of SlROP4 (SlROP4DN) exhibited enhanced drought tolerance, as evidenced by improved growth, higher relative water content, reduced water loss, and increased chlorophyll retention under drought conditions. These plants accumulated lower levels of reactive oxygen species and malondialdehyde, indicating reduced oxidative damage, without significant changes in antioxidant enzyme activities. Moreover, SlROP4DN plants showed increased sensitivity to abscisic acid, with enhanced ABA-induced stomatal closure and upregulation of ABA-responsive genes. Together, these results indicate that SlROP4 modulates drought tolerance and suggest SlROP4 as a promising target for improving drought tolerance in tomato.PMID:42285419 | DOI:10.1016/j.plantsci.2026.113273