Product Description

A structurally diverse repertoire of ligands, from photons to large peptides, activates GPCRs to elicit their physiological functions. Ligand-bound GPCRs, in turn, function as guanine nucleotide exchange factors catalyzing the exchange of GDP bound on the Gα subunit with GTP in the presence of Gβγ, causing the dissociation of the Gα subunit from the Gβγ dimer to form two functional units (Gα and Gβγ). Both Gα and Gβγ subunits signal to various cellular signaling pathways. Based on the sequence and functional homologies, G proteins are grouped into four families: G_s, G_i, G_q, and G₁₂. As increasing numbers of effectors and interacting proteins for these G proteins have been identified, the physiological processes in which G proteins participate are multiplying.