Summary
Heterotrimeric G proteins transmit signals from a wide range of cell surface G protein-coupled receptors (GPCRs) to mediate multiple cellular events. Within the plasma membrane, G proteins interact with GPCRs and effector proteins such as adenylyl cyclase (AC) and phospholipase C (PLC). Plasma membrane subdomains (e.g., lipid rafts and caveolae) may organize and regulate these interactions. G protein subunits have been reported to be in additional cellular regions, such as the Golgi apparatus and the cytoskeleton, and G protein α subunits may move within the cell during the activation cycle. Changes in the cellular localization of α subunits could be important for interactions with effectors that are not in the plasma membrane and/or could be a means for terminating G protein signaling. However, until recently, the topic of G protein α subunit localization under basal and activated conditions has been controversial, partly because of spatial and temporal limitations inherent to procedures like cell fractionation and immunohistochemistry. Green fluorescent protein (GFP)-tagging is a useful way to enable real-time visualization of proteins in living cells. This chapter describes how to produce and visualize functional GFP-tagged α subunits and to investigate whether activation affects their subcellular localization.
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Hynes, T.R., Hughes, T.E., Berlot, C.H. (2004). Cellular Localization of GFP-Tagged α Subunits. In: Smrcka, A.V. (eds) G Protein Signaling. Methods in Molecular Biology™, vol 237. Humana Press. https://doi.org/10.1385/1-59259-430-1:233
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DOI: https://doi.org/10.1385/1-59259-430-1:233
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