UV-Vis- and IR-spectroscopy provides insights into the light-induced enzyme activity of a rhodopsin guanylyl cyclase by tracking the substrate turnover with atomic resolution in real-time and correlating it with the structural changes of the protein.

Functional assays using zebrafish reveal that various microbial channelrhodopsins, guanylyl cyclase rhodopsin, and photoactivated adenylyl cyclases function as potent optogenetic tools, effectively controlling neural activity and cardiac function in zebrafish.