1. The β adrenergic receptor (βAR)
The β adrenergic receptor (βAR). This two-dimensional bead-on-a string model illustrates features common to most heptaspanning GPCRs. Red lines mark 10-amino acid regions. The amino terminus (N) is extracellular and the carboxyl terminus (C) is intracellular; in between are 7 hydrophobic transmembrane (TM) domains and alternating intracellular and extracellular loops (e1-3 and i1-3). Glycosylation sites are found near the N terminus; consensus sites for phophorylation by PKA (arrows) are found in the i3 loop and the carboxy terminal tail. Multiple sites for βARK occur throughout the carboxy terminal region. An aspartate residue in TM3 (asp113) interacts with the nitrogen of catecholamine agonists while two serines (ser204, ser207) in TM5 interact with the hydroxyl groups on the phenyl ring of catecholamine agonists. A cysteine residue (cys 341) is a substrate for palmitoylation. Interaction of the palmitoyl group with membrane lipids reduces the flexibility of the carboxy tail. (Reprinted by permission from Macmillan Publishers Ltd: Rasmussen SGF, Choi H-J, Rosenbaum DM et al: Crystal structure of the human β2 adrenergic G-protein-coupled receptor. Nature 450:383, Copyright © 2007.)
Source: Neurotransmission and the Central Nervous System, Goodman & Gilman's: The Pharmacological Basis of Therapeutics, 12e
Citation: Brunton LL, Chabner BA, Knollmann BC. Goodman & Gilman's: The Pharmacological Basis of Therapeutics, 12e; 2011 Available at: Accessed: October 12, 2017
Copyright © 2017 McGraw-Hill Education. All rights reserved