Jasmonic acid signaling in plants: regulatory mechanisms in development and stress responses

Jasmonic acid (JA), one of the most pivotal plant hormones, has emerged as a central focus in plant biology research due to its extensive and diverse biological functions. This review synthesizes the significant advancements made over the past decade in understanding JA's role in regulating plant development and mediating responses to environmental stresses, areas that lacked systematic review in previous years. We provide a concise overview of JA's biosynthetic and signal transduction pathways, with particular emphasis on the key regulatory complex comprising CORONATINE INSENSITIVE 1 (COI1), jasmonate ZIM-domain proteins (JAZs), and MYC transcription factors (MYCs). The COI1-JAZs-MYCs complex serves as a master regulator of various developmental processes, including seed germination, root elongation, and leaf senescence. Although early research primarily highlighted JA's role in enhancing plant resistance to insects and pathogens through JAZ-mediated modulation of secondary metabolites, reactive oxygen species, and defense-related gene expression, recent evidence underscores its pivotal coordination with other plant hormones, regulatory genes, and metabolites in mediating responses to abiotic stresses such as drought, salinity, and temperature extremes. Furthermore, this article offers a forward-looking perspective on the future directions of JA research, emphasizing its potential applications in improving crop resilience and productivity.