Molecular mechanisms and evolutionary history of phytomelatonin in flowering

Phytomelatonin is a phytohormone that potentially modulates flowering. To aid in understanding this function, the underlying molecular mechanisms and evolutionary history of phytomelatonin-mediated flowering are described. Flowering is a critical stage in plant life history, which is coordinated by environmental signals and endogenous cues. Phytomelatonin is a widely distributed indoleamine present in all living organisms and plays pleiotropic roles in plant growth and development. Recent evidence has established that phytomelatonin could modulate flowering in many species, probably in a concentration-dependent manner. Phytomelatonin seems to associate with floral meristem identification and floral organ formation, and the fluctuation of phytomelatonin might be important for flowering. Regarding the underlying mechanisms, phytomelatonin interacts with the central components of floral gene regulatory networks directly or indirectly, including the MADS-box gene family, phytohormones, and reactive oxygen species (ROS). From an evolutionary point of view, the actions of phytomelatonin in flowering probably evolved during the period of the diversification of flowering plants and could be regarded as a functional extension of its primary activities. The presumed evolutionary history of phytomelatonin-modulated flowering is proposed, presented in the chronological order of the appearance of phytomelatonin and core flowering regulators, namely DELLA proteins, ROS, and phytohormones. Further efforts are needed to address some intriguing aspects, such as the exploration of the association between phytomelatonin and photoperiodic flowering, phytomelatonin-related floral MADS-box genes, the crosstalk between phytomelatonin and phytohormones, as well as its potential applications in agriculture.

Automated summary

Phytomelatonin potentially modulates flowering in a concentration-dependent manner by interacting with floral gene regulatory networks. From an evolutionary perspective, phytomelatonin-mediated flowering is believed to have evolved during the diversification of flowering plants as a functional extension of its primary activities. Further research is needed to explore the association between phytomelatonin and photoperiodic flowering, its interaction with phytohormones, and its potential applications in agriculture.