Methyl jasmonate-induced postharvest disease resistance in Agaricus bisporus is synergistically regulated by AbbZIP2 and AbMYB11 to facilitate ROS balance

Abstract

Brown blotch disease caused by Pseudomonas tolaasii, poses a significant threat to the postharvest storage of edible mushrooms. This disease leads to rapid browning in Agaricus bisporus, significantly shortening its shelf life. The defense mechanisms of mushrooms against the pathogen during the postharvest stage remain unknown. Here, we reported that the ascorbate-glutathione (AsA-GSH) cycle played a critical role in the methyl jasmonate (MeJA)-induced postharvest disease resistance in A. bisporus. Importantly, we identified and characterized an A. bisporus basic leucine zipper (bZIP) transcription factor (AbbZIP2) that was involved in MeJA-induced disease resistance by directly repressing the transcription of AsA-GSH cycle-related genes. Furthermore, we demonstrated that AbbZIP2 interacted with a 3R-MYB TF (AbMYB11), which independently activated the AsA-GSH cycle-related genes and attenuated the transcriptional repression of AbbZIP2 on AsA-GSH cycle-related genes. Additionally, AbbZIP2 and AbMYB11 transcriptionally regulated with each other. Our findings revealed a novel AbbZIP2- and AbMYB11-mediated regulatory network involved in the AsA-GSH cycle to maintain the balance of reactive oxygen species and collectively contribute to disease resistance in A. bisporus during postharvest storage. This study provided important theoretical insights for extending shelf life and reducing postharvest losses.