CaMYB80 Enhances Cold Tolerance in Pepper by Regulating ROS Scavenging and Stress Gene Networks | Newswise

Researchers at Sichuan Agricultural University have uncovered a key molecular mechanism that enhances cold tolerance in pepper plants, which are typically sensitive to low temperatures. Their study, published in Horticulture Research, demonstrates that the transcription factor CaMYB80 plays a pivotal role by directly activating the gene CaPOA1, involved in detoxifying reactive oxygen species (ROS). This activation bolsters the plant's antioxidant defenses and amplifies cold-responsive gene expression, including the ICE-CBF-COR pathway, improving overall resilience. In experiments, silencing CaMYB80 led to decreased photosynthetic efficiency and increased cellular damage under cold stress, while overexpressing it in Arabidopsis and tomato resulted in heightened cold tolerance, with increased antioxidant enzyme activity and reduced oxidative damage. Further analysis confirmed that CaMYB80 binds directly to the promoter of CaPOA1, facilitating its expression and contributing to ROS scavenging. These findings position CaMYB80 as a master regulator that links cold perception with antioxidant and gene regulatory networks, offering promising avenues for breeding cold-resistant pepper vari...