Abstract:
Melatonin is a conserved small molecule substance in the process of biological evolution and is involved in the regulation of circadian rhythm in animals. Since the discovery of plant melatonin, scholars have studied its synthesis pathways, physiological functions, and mechanisms of action, and found that it is involved in the regulation of plant growth and development (root and fruit development) and cell redox balance. For the plant melatonin synthesis pathway, researchers have found that melatonin exists in a variety of plants and its synthesis-related genes have been cloned. The subcellular localization of melatonin synthesis-related proteins differs among plants, and thus the synthesis site also differs from plant to plant. This article reviews the current status of research on the plant melatonin synthesis pathways, subcellular localization, and synthesis regulation, with a focus on the regulation of subcellular localization and enzyme kinetics in upstream synthesis. We also discuss prospects for future research.