Regulates G protein-coupled receptor signaling cascades, including signaling via muscarinic acetylcholine receptor CHRM2 and dopamine receptor DRD2. Inhibits signal transduction by increasing the GTPase activity of G protein alpha subunits, thereby driving them into their inactive GDP-bound form. Binds selectively to GNAZ and GNAI2 subunits, accelerates their GTPase activity and regulates their signaling activities. Negatively regulates mu-opioid receptor-mediated activation of the G-proteins. RGS17 Protein, Human, Recombinant (GST) is expressed in E. coli expression system with N-GST tag. The predicted molecular weight is 51.4 kDa and the accession number is Q9UGC6.