Heterotrimeric G proteins, which consist of alpha, beta, and gamma subunits, function as signal transducers for the 7-transmembrane-helix G protein-coupled receptors. GNG13 is a gamma subunit that is expressed in taste, retinal, and neuronal tissues and plays a key role in taste transduction Recombinant human GNG13 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.