Optogenetic Manipulations of Small GTPases and Observations of Their Intracellular Functions

Abstract

Rho and Ras family small GTPases are activated by extracellular stimuli and regulate numerous cellular processes, including cell motility, proliferation, and differentiation. Although biosensors have revealed the distribution of their intracellular activity, it is necessary to manipulate their activity and observe cellular responses to understand their functions accurately. Optogenetics is a technology that uses light-responsive proteins to manipulate the activity of signaling molecules by light irradiation. Optogenetics has made it possible to manipulate small GTPases in living cells with high spatiotemporal resolution. In this article, we review the manipulation of small GTPases by optogenetics and observation of their intracellular functions using biosensors, focusing on our recent study in which we constructed optogenetic tools to control six members of small GTPases and analyzed the crosstalk between small GTPases and intracellular calcium signaling.