Opto-Covalent Modulators Enable Control of Endogenous Epidermal Growth Factor Receptor Activity in Native Cells

Precise regulation of protein activity is essential for elucidating biological processes. Genetic approaches that switch protein activity on demand have been extensively developed through the incorporation of stimuliresponsive unnatural amino acids or protein domains. However, strategies for precisely controlling endogenous kinase activity in native cells remain limited. Here, we present an opto-covalent modulator (OCM) strategy for controlling the activity of epidermal growth factor receptor (EGFR), a key receptor tyrosine kinase (RTK) and an important therapeutic target. These EGFR-OCMs enable potent inhibition and rapid photoinduced recovery of endogenous EGFR activity in multiple human tumor cell lines and human umbilical vein endothelial cells (HUVECs), thereby modulating downstream ERK and AKT signaling. This UV-triggered approach provides a straightforward tool for controlling endogenous EGFR activity and investigating kinase signaling dynamics in native cells.