GNAT2

Alpha subunit of the heterotrimeric guanine nucleotide-binding protein (G protein) that transduces signals from the G protein-coupled cone photoreceptors (blue, green and red cones). Functions as a GTPase, cycling between an active GTP-bound state and an inactive GDP-bound state. Upon photoactivation, cone photoreceptors promote GDP release and GTP binding (By similarity). In its active state, GNAT2 stimulates downstream effectors, including the cone cGMP-phosphodiesterase (PDE6) complex, to mediate the phototransduction cascade (By similarity). Activation of the PDE6 complex occurs through binding and repositioning of the inhibitory PDE6 gamma subunits (PDE6H), thereby promoting catalytic activity (By similarity)..

Function from UniProtKB (P19087), read 2026-09-23. CC BY 4.0.