Beta2 adrenergic receptor-Gs protein complex: Difference between revisions

The α5-helix of Gαs docks into a cavity formed on the intracellular side of the receptor by the opening of transmembrane helices 5 and 6. Within the transmembrane core, the interactions are primarily non-polar - an exception involves <scene name='70/701430/Receptor_g_protein_interaction/4'>packing</scene> of Tyr 391 of the α5-helix against Arg 131 of the conserved DRY sequence in TM3. Arg 131 also packs against Tyr 326 of the conserved NPxxY sequence in TM7. As the α5-helix exits the receptor it forms a network of polar interactions with TM5 and TM3. Receptor residues Thr 68 and Asp 130 interact with the ICL2 helix of the β2AR via Tyr 141, positioning the helix so that Phe 139 of the receptor <scene name='70/701430/Receptor_gprotein_interaction2/1'>docks into</scene> a hydrophobic pocket on the G protein surface, thereby structurally linking receptor–G protein interactions with the highly conserved DRY motif of the β2AR.