The NAC transcription factors enhance the yield of natural products in plants: regulatory mechanisms of secondary metabolic pathways

Plant secondary metabolites constitute a significant category of natural products that possess both practical applications and ecological functions. These compounds are extensively utilized in pharmaceutical research and development, industrial production, and various other fields. Notable examples include artemisinin, a highly effective antimalarial drug, and ginsenosides, which are bioactive compounds with a wide range of pharmacological activities. Additionally, these metabolites are crucial for the adaptive evolution of plant species, serving as essential defenses against biotic and abiotic stresses and acting as key mediators in ecological interactions between plants, their environments, and other organisms. NAC transcription factors (TFs), which are plant-specific regulatory hubs, have been increasingly recognized for their pivotal role in the regulation of plant secondary metabolism. Despite this recognition, comprehensive reviews of their regulatory mechanisms are relatively limited. This review aims to synthesize the core regulatory functions of NAC TFs in the biosynthesis of plant secondary metabolites and systematically elucidate their molecular mechanisms, particularly in the biosynthesis of terpenoids and phenolic compounds.