Figure 3.

Photocontrol of TEV protease activity in mammalian cells. (a) Strategy for photoactivating TEV protease. Caging a catalytic cysteine (C151) in TEV protease deactivates it. TEV protease can be rapidly activated by removing the caging group with light. (b) Site-specific incorporation of 2 in TEV protease. Full-length TEV-C151-2 was expressed in HEK293T cells in the presence of 2 and the MmPCC2RS/tRNA_CUA pair. (c) TEV protease can be efficiently activated with light in HEK293T cells. Cells were illuminated (1 min, 365 nm,∼4 mW/cm²). All cells contained the reporter of TEV protease activity.