Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - AB 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 53577.38 
• Atom Count: 3034 
• Residue Count: 476 
• Unique protein chains: 2

4MQS

Structure of active human M2 muscarinic acetylcholine receptor bound to the agonist iperoxo

• DOI: 10.2210/pdb4MQS/pdb

• Classification: SIGNALING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Spodoptera frugiperda, Escherichia coli BL21(DE3)
• Mutation(s): 6 


• Deposited: 2013-09-16 Released: 2013-11-27 
• Deposition Author(s): Kruse, A.C., Ring, A.M., Manglik, A., Hu, J., Hu, K., Eitel, K., Huebner, H., Pardon, E., Valant, C., Sexton, P.M., Christopoulos, A., Felder, C.C., Gmeiner, P., Steyaert, J., Weis, W.I., Garcia, K.C., Wess, J., Kobilka, B.K.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.5 Å
• R-Value Free: 0.298 
• R-Value Work: 0.249 

Literature

Activation and allosteric modulation of a muscarinic acetylcholine receptor.

Kruse, A.C., Ring, A.M., Manglik, A., Hu, J., Hu, K., Eitel, K., Hubner, H., Pardon, E., Valant, C., Sexton, P.M., Christopoulos, A., Felder, C.C., Gmeiner, P., Steyaert, J., Weis, W.I., Garcia, K.C., Wess, J., Kobilka, B.K.

(2013) Nature 504: 101-106

• PubMed: 24256733 
• DOI: 10.1038/nature12735
• Primary Citation of Related Structures:  
  4MQT


• PubMed Abstract: 
  

Despite recent advances in crystallography and the availability of G-protein-coupled receptor (GPCR) structures, little is known about the mechanism of their activation process, as only the β2 adrenergic receptor (β2AR) and rhodopsin have been crystallized in fully active conformations. Here we report the structure of an agonist-bound, active state of the human M2 muscarinic acetylcholine receptor stabilized by a G-protein mimetic camelid antibody fragment isolated by conformational selection using yeast surface display. In addition to the expected changes in the intracellular surface, the structure reveals larger conformational changes in the extracellular region and orthosteric binding site than observed in the active states of the β2AR and rhodopsin. We also report the structure of the M2 receptor simultaneously bound to the orthosteric agonist iperoxo and the positive allosteric modulator LY2119620. This structure reveals that LY2119620 recognizes a largely pre-formed binding site in the extracellular vestibule of the iperoxo-bound receptor, inducing a slight contraction of this outer binding pocket. These structures offer important insights into the activation mechanism and allosteric modulation of muscarinic receptors.

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Organizational Affiliation: 

1] Department of Molecular and Cellular Physiology, Stanford University School of Medicine, 279 Campus Drive, Stanford, California 94305, USA [2].

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Muscarinic acetylcholine receptor M2	A	351	Homo sapiens	Mutation(s): 6  Gene Names: CHRM2
Membrane protein mpstruct	Group:  TRANSMEMBRANE PROTEINS: ALPHA-HELICAL		Sub Group:  G Protein-Coupled Receptors (GPCRs)	Protein:  M2 human muscarinic acetylcholine receptor bound to an antagonist
Find proteins for P08172 (Homo sapiens) Go to Gene View: CHRM2 Go to UniProtKB:  P08172

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
Nanobody 9-8	B	125	N/A	Mutation(s): 0
Protein Feature View is not available: No corresponding UniProt sequence found.

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
IXO	A	4-(4,5-dihydro-1,2-oxazol-3-yloxy)-N,N,N-trimethylbut-2-yn-1-aminium Iperoxo C10 H17 N2 O2 WXXOCGISBCTWPW-UHFFFAOYSA-N

External Ligand Annotations
ID	Binding Affinity (Sequence Identity %)
IXO	EC50: 0.1 - 0.2 nM (86) BINDINGDB

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.5 Å
• R-Value Free: 0.298 
• R-Value Work: 0.249 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length (Å)	Angle (°)
a = 62.896	α = 90.00
b = 78.130	β = 90.00
c = 163.482	γ = 90.00

Software Package:

Software Name	Purpose
PHENIX	refinement
HKL-2000	data reduction
PHASER	phasing
HKL-2000	data scaling
HKL-2000	data collection

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-09-16 
• Released Date: 2013-11-27 
• Deposition Author(s): Kruse, A.C., Ring, A.M., Manglik, A., Hu, J., Hu, K., Eitel, K., Huebner, H., Pardon, E., Valant, C., Sexton, P.M., Christopoulos, A., Felder, C.C., Gmeiner, P., Steyaert, J., Weis, W.I., Garcia, K.C., Wess, J., Kobilka, B.K.

Revision History 

• Version 1.0: 2013-11-27
  Type: Initial release
• Version 1.1: 2013-12-04
  Type: Database references
• Version 1.2: 2013-12-18
  Type: Database references
• Version 1.3: 2017-07-05
  Type: Source and taxonomy