Optical inactivation of intracellular molecules by fast-maturating photosensitizing fluorescence protein, HyperNova.

Photosensitizing fluorescence protein is a promising tool for chromophore-assisted light inactivation (CALI) that enables specific oxidation and inactivation of intracellular molecules. However, a commonly used monomeric photosensitizing fluorescent protein, SuperNova, shows a low CALI efficiency due to its insufficient maturation at 37 °C, thereby limiting the application of CALI to various molecules, especially in mammalian cells. Here, we present a photosensitizing fluorescence protein, HyperNova, with markedly improved maturation at 37 °C, leading to greatly enhanced CALI efficiency. Exploiting this quality, HyperNova enables the application of CALI to variety of molecules such as a mitotic kinase and transcriptional factors that were highly challenging with conventional SuperNova. To further demonstrate the utility of HyperNova, we have also succeeded in developing novel CALI techniques for MAP kinases by HyperNova. Our findings suggest that HyperNova has the potential to expand the molecular toolbox for manipulating biological events in living cells, providing new avenues for investigating cellular signaling pathways.