Miyazaki, T.; Fujino, T.; Yoshii, T.; Funane, M.; Murata, N.; Kim, C. N.; Nagatoishi, S.; Tsumoto, K.; Hayashi, G.; Murakami, H.; Tsukiji, S.

Optical control of biomolecules is a powerful technique for biological research, but current tools derived from natural proteins face significant limitations. Engineering these proteins to meet researchers\' needs remains challenging. In this study, we present a novel approach to the de novo creation of tailored chemo-optogenetic tools. This method combines the rational design of synthetic photo-switchable molecules with in vitro selection of artificial protein binders that specifically recognize a particular conformation of these molecules. We demonstrate the utility of this approach by generating artificial proteins that bind exclusively to the cis-form of designed azobenzene derivatives. The newly created pairs enable sustained protein activation with a single light pulse and allow for precise, reversible, and repeatable switching of cellular processes using two distinct wavelengths of light in mammalian cells. This de novo technique provides tailored synthetic photoswitch-protein binder pairs, expanding the potential for optical biomolecule manipulation.