<p>This entry represents the G protein gamma subunit and the GGL (G protein gamma-like) domain, which are related in sequence and are comprised of an extended alpha-helical polypeptide. The G protein gamma subunit forms a stable dimer with the beta subunit, but it does not make any contact with the alpha subunit, which contacts the opposite face of the beta subunit. The GGL domain is found in several RGS (regulators of G protein signaling) proteins. GGL domains can interact with beta subunits to form novel dimers that prevent gamma subunit binding, and may prevent heterotrimer formation by inhibiting alpha subunit binding. The interaction between G protein beta-5 neuro-specific isoforms and RGS GGL domains may represent a general mode of binding between beta-propeller proteins and their partners [<cite idref="PUB00015235"/>].</p>