Melatonin in Plants

Melatonin is a ubiquitous, highly conserved molecule plays a pivotal role in the regulation of a range of biological responses in phylogenetically very distant organisms including humans and plants. Melatonin mediated responses in plants include circadian rhythms, growth and reproduction, senescence, and protection against environmental stresses such as cold, UV, toxic ions. Findings in our laboratory have revealed the presence of melatonin and serotonin at relatively high levels in several medicinal plant species that are used in the treatment of neurological disorders, including St. John's wort, feverfew and huang-qin. Despite the evidence of the presence of Mel in a range of responses, the mechanisms of its actions in plants have largely remained speculative. Our research is focused on understanding the role of melatonin in plant morphogenesis, development, and adaptation in changing environments.