Methyl jasmonate activated regulatory module Ma14-3-3e-MbHLH130-MbACO13/MbACS7 promoting ethylene biosynthesis and fruit ripening in banana

Abstract

Methyl jasmonate (MeJA), an important phytohormone, plays a vital role in many biological processes. However, its effect and mechanism in regulating ethylene synthesis and fruit ripening in banana remain unknown. In this research, we found that exogenous MeJA accelerated postharvest ripening of banana, which coincided with increased ethylene production and upregulation of MbACS7 and MbACO13 expression. MabHLH130 directly interacted with and stimulated the transcription of MbACS7 and MbACO13. Additionally, MabHLH130 interacted with Ma14-3-3e through the RHSSSP motif. Overexpression of either MabHLH130 or Ma14-3–3e in tomato promoted ethylene production and fruit ripening, and this effect was enhanced by exogenous MeJA treatment. Furthermore, the Ma14-3–3e-MabHLH130 interaction module activated MbACS7 and MbACO13 transcription, which was enhanced by exogenous MeJA treatment. Taken together, these results demonstrated that the MeJA-responsive Ma14-3–3e-MabHLH130-MbACS7/MbACO13 module promoted ethylene biosynthesis and fruit ripening in bananas, providing valuable genetic targets for breeding programs aimed at extending fruit shelf-life.