Abstract

High temperature has posed significant challenges to global agriculture, markedly leading to reduced fertility and yield losses in tomato ( Solanum lycopersicum ). Therefore, thermotolerance-conferring genes and loci are needed to further improve cultivated tomatoes. Here we identified an E3 ubiquitin ligase SlRNF185 , containing a C3HC4-type RING-HC domain, that confers tomato pollen thermotolerance. As a predominant ubiquitination member, SlRNF185 could degrade the SlVPS29 protein induced by heat stress to enhance thermotolerance. Mechanistically, we found that a heat shock transcription factor SlHSFA7 dramatically activates the expression of SlRNF185 under heat stress and acts as a positive regulator of tomato pollen thermotolerance. Collectively, our findings reveal that a SlHSFA7-SlRNF185 genetic module regulates ubiquitination-mediated degradation of SlVPS29 under heat stress, providing the strategy for breeding thermotolerance tomato varieties.