G Protein (Heterotrimeric) Activators

Heterotrimeric G proteins are membrane bound GTPases that are linked to 7-TM receptors. Each G protein contains an α-, β- and γ-subunit and is bound to GDP in the 'off' state. Ligand binding to a 7-TM receptor causes a conformational change in the receptor, which detaches the G protein. This switches the G protein to an 'on' state, allowing GTP to displace GDP, thus G_α can activate second messenger signaling cascades.

There are several types of G_α ...