Figure 2.

Models of GPR126 activation. (A) GPR126 functions via a variety of G protein signaling. The N-terminal subdomains are indicated in multiple colored modules to reflect the potential activities. (B) In the orthosteric agonism model of activation, the ligand–receptor interactions trigger the dissociation of NTF and CTF, resulting in the exposure of the tethered peptide to facilitate its binding to an orthosteric site within the 7TM. (C) In the allosteric activation model, various ligands bind to diverse domains of the receptor to activate or inhibit the GPR126-mediated signaling.