Regulation of cellular signals by G-proteins

摘要

Extracellular signals are transduced across the cell by the cell surface receptors, with the aid of G-proteins, which act at a critical point of signal transduction and cellular regulation. Structurally, G-proteins are heterotrimeric consisting α, β and γ subunits hot in functionally active state they dissociate into α subunit coupled to GTP and as βγ dimer. G-proteins can he broadly divided into two classes based on their sensitivity to pertussis toxin and cholera toxin. Existence of various forms of each of the subunit allows molecular diversity in the subunit species of G-proteins.