Fig. 3. Active conformation of GHSR.

Conformational changes of the extracellular regions of TM6 and TM7 (a), the highly conserved transmission switch residues (b), and cytoplasmic regions of TMs (c) in the active GHSR relative to them in the inactive GHSR. Two active GHSR bound to ghrelin and ibutamoren and the inactive GHSR bound to C12 (PDB code 6KO5) are colored in blue, green, and purple, respectively. Ghrelin, ibutamoren and C12 are shown as orange, yellow and lemon sticks, respectively. Red arrows indicate changes of residues or regions from inactive to active states.