Once transducin alpha subunit (GNAT1) is deactivated by hydrolysis of bound GTP to GDP, it reassociates with transducin beta:gamma subunits (GNB1:GNGT1) to form inactive transducin (Gt-GDP). A stoichiometric overabundance of GNB1:GNGT1 facilitates the reassociation event. The details for this event were revealed in bovine experiments (Clark et al. 2006, Fung et al. 1981).