Transcriptome and biochemical analyses of glutathione-dependent regulation of tomato fruit ripening

Delay the ripening can improve fruit shelf life. Reduced glutathione (GSH) is an antioxidant that delays the ripening of fruits, though the GSH-mediated mechanism involved in fruit-ripening processes is currently unclear. This study used RNA sequencing to assess the GSH-induced transcriptional and biochemical alterations observed in tomato fruit during the post-harvest process. We found 970 differentially expressed genes (DEGs) after GSH treatment, and 124 were found to be candidate genes related to the ripening of GSH-mediated fruit. In addition, the expression levels of several candidate DEGs observed in ripe tomato fruit after GSH treatments were confirmed using quantitative real-time PCR. Biochemical analyses revealed that the GSH treatment decreased the proline content and the lipid peroxidation and ascorbate peroxidase activity levels. In contrast, it increased the superoxide dismutase, peroxidase, and catalase activity levels, as well as endogenous glutathione and ascorbic acid contents. These results confirm the important role played by GSH during the process of ripening tomato fruit.