Figure 5.

Biased agonism and signaling selectivity. Biased agonism is a recently emerging concept in which a ligand preferentially activates one signaling pathway over another. In balanced agonism, binding of a ligand potentiates both G protein and β-arrestin signaling. However, when a β-arrestin-biased-ligand binds to a GPCR, conformational changes in the receptor favor β-arrestin-mediated signaling while silencing of G protein-mediated pathways. Similarly, when a G protein-biased ligand binds to the GPCR, conformational changes in the receptor favor G protein-mediated signaling while silencing β-arrestin signaling. Figure created with BioRender.com. GPCR, G protein-coupled receptor; GTP, guanosine triphosphate.