Abstract

G protein-coupled receptor (GPCR)-Gα fusion proteins were first characterized more than 10 years ago as a strategy for studying receptor-G protein signaling. A large number of studies have used this approach to characterize receptor coupling to members of the G_s, G_i, and G_q families of Gα subunits, but this strategy has not been widely used to study Gα₁₂ and Gα₁₃. As described in the article by Zhang et al. in this issue of Molecular Pharmacology (p. 1433) characterization of the signaling properties of thromboxane A₂ receptor (TPα) -Gα₁₂ and -Gα₁₃ fusion constructs demonstrates the applicability of this strategy to members of this unique family of Gα subunits, and how this strategy can be used to resolve otherwise difficult problems of receptor pharmacology associated with these proteins. The general strategy of making receptor-Gα fusion constructs has wide applicability to a number of research problems, but there are perhaps also “hidden messages” in how different receptor-Gα subunit fusion pairs behave.