Banana ERF transcription factor MaERF110 is involved in ethylene-induced chilling tolerance by regulating ROS accumulation

Abstract

Banana fruit is susceptive to chilling injury (CI), resulting in quality deterioration. Although ethylene treatment alleviates banana CI symptom, the underlying mechanism remains largely unknown. Here, as compared with control banana fruit, ethrel (an ethylene-releasing compound) treatment maintained lower levels of CI index and relative electrolytic leakage, lower contents of malondialdehyde (MDA) and reactive oxygen species (ROS) in cold-stored fruit and inhibited the expressions of ROS-synthesis genes, including MaRbohB, MaRbohE, and MaRbohJ. A potential upstream regulator of MaRbohE was identified by Yeast one-hybrid assay and named as MaERF110. Ethrel repressed MaERF110 expression during cold storage, and MaERF110 protein was localized in the nucleus with transcriptional activation activity. Gel mobility shift assay and dual-luciferase reporter assay displayed that MaERF110 bound to GCC-box in the promoters of MaRbohB, MaRbohE, and MaRbohJ and activated their expressions. Thus, the results expand our understandings of ethylene-improved chilling tolerance in banana fruit during cold storage.