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.

Center for Nanobiology and Structural Biology Institute of Microbiology of the Czech Academy of Sciences Nove Hrady Czech Republic

Faculty of Science University of South Bohemia Ceske Budejovice Czech Republic

Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Prague Czech Republic

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