Rationally improving LOV domain–based photoswitches

Abstract

Light-sensitive LOV domains show much promise for engineering proteins with photoswitchable activity. The dynamic range of a LOV domain is now substantially improved by the introduction of beneficial mutations predicted by an analytical model of photoswitching. The approach should prove useful to improve the function of multiple LOV-based switches. Genetically encoded protein photosensors are promising tools for engineering optical control of cellular behavior; we are only beginning to understand how to couple these light detectors to effectors of choice. Here we report a method that increases the dynamic range of an artificial photoswitch based on the LOV2 domain of Avena sativa phototropin 1 (AsLOV2). This approach can potentially be used to improve many AsLOV2-based photoswitches.