This talk will focus on how plants “sense” light and will introduce major discoveries in plant photobiology together with their potential applications in optogenetics. Plants rely on diverse photoreceptors to precisely perceive environmental light signals, including the UV-B photoreceptor UVR8 and the red/far-red light photoreceptors phytochromes. The presentation will highlight the molecular mechanisms underlying light perception by these receptors. For example, UVR8 directly senses UV-B through key tryptophan residues, undergoes conformational changes from a homodimer to monomers, and subsequently translocates from cytosol into the nucleus, where it stabilizes HY5 through interaction with COP1 or directly regulates transcription factor activities, thereby triggering large-scale transcriptional reprogramming. In parallel, classical phytochrome signaling mechanisms, such as phyA nuclear import mediated by FHY1, will also be discussed.
Building on these examples, the talk will further address several major unanswered questions in plant photobiology, including how plants perceive green light and longer wavelengths, and whether additional photoreceptors remain to be discovered. Importantly, many photoreceptors mediate highly light-dependent protein–protein interactions, such as the UVR8–COP1 and phyA–FHY1 systems. These properties provide versatile modules for the development of optogenetic tools and hold great promise for applications in precise cellular regulation, disease therapy, and synthetic biology.
Speaker
Prof. Yinruo He
School of Agriculture and Biology, SJTU
Time
2026.5.27 12:00-13:30