Fig. 6: VIPR1 defines a third mode of endosomal GPCR signaling.
From: β-Arrestin-independent endosomal cAMP signaling by a polypeptide hormone GPCR
The diagram illustrates key distinctions among signaling modes. Mode 1: β-arrestin enables signaling from endosomes by promoting receptor internalization and then dissociating. Mode 2: β-arrestin promotes receptor internalization and then remains bound after internalization to form a signal-sustaining endosomal megaplex. Mode 3: β-arrestin is not required for receptor internalization or signaling from endosomes; instead, β-arrestin sculpts the resulting combined signal output, such that the plasma membrane and endosomal signal phases produce temporally resolved cAMP peaks.
