Optical sensors of heterotrimeric G protein signaling.

Heterotrimeric G proteins are central mediators of cellular signal transduction. They receive, process, and transduce signals from G protein-coupled receptors to downstream effectors. Since their discovery, a number of optical sensors of G protein localisation and function have been developed and applied in living systems. In this minireview, we provide an overview of existing G protein-based sensors and the experimental approaches they utilise, with emphasis on live-cell imaging techniques. We outline recent advances, as well as identify current challenges and likely future directions in the field of G protein sensor development.