ABC transporter SlABCG23 regulates chilling resistance of tomato fruit by affecting JA signaling pathway

To explore the effect and mechanism of an ATP-binding cassette transporter, SlABCG23, on the chilling resistance of tomato fruit during storage, we generated mutant using CRISPR/Cas9 technology for further investigation. This research showed under cold stress, the slabcg23 mutant fruit exhibited severe chilling injury (CI), lower jasmonic acid (JA) contents, and higher expression levels of JA signaling inhibitor, SlJAZ6, than wild-type (WT). The mutation of SlABCG23 caused a decrease in the thickness of the fruit pericarp. The expression levels of SlCBF1 and SlICE1 in slabcg23 mutant fruit were lower than those in WT fruit under cold stress. Moreover, the slabcg23 mutant fruit exhibited reduced activities of antioxidant enzymes, including superoxide dismutase, catalase and peroxidase, and increased reactive oxygen species and malondialdehyde contents. These findings indicated that SlABCG23 affects fruit resistance to CI by influencing the JA signaling pathway, fruit pericarp development, cold response signal and antioxidant capacity.

Automated summary

In this study, we investigated the effect and mechanism of an ATP-binding cassette transporter, SlABCG23, on the chilling resistance of tomato fruit during storage. We found that mutation of SlABCG23 resulted in severe chilling injury, decreased jasmonic acid contents, and increased expression levels of the JA signaling inhibitor, SlJAZ6. This mutation also led to a decrease in fruit pericarp thickness, lower expression levels of cold response genes, and reduced antioxidant enzyme activities.