Biological Assembly 1  

 3D View: Structure | Electron Density | Validation Report | Ligand Interaction | Predict Membrane 

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 48.26 kDa 
• Atom Count: 3056 
• Modelled Residue Count: 398 
• Deposited Residue Count: 425 
• Unique protein chains: 1

4L6R

Structure of the class B human glucagon G protein coupled receptor

• DOI: 10.2210/pdb4L6R/pdb

• Classification: MEMBRANE PROTEIN
• Organism(s): Escherichia coli, Homo sapiens
• Expression System: Spodoptera frugiperda
• Mutation(s): Yes 
• Membrane Protein: Yes  OPMPDBTMmpstruc


• Deposited: 2013-06-12 Released: 2013-07-24 
• Deposition Author(s): Siu, F.Y., He, M., de Graaf, C., Han, G.W., Yang, D., Zhang, Z., Zhou, C., Xu, Q., Wacker, D., Joseph, J.S., Liu, W., Lau, J., Cherezov, V., Katritch, V., Wang, M.W., Stevens, R.C., GPCR Network (GPCR)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.30 Å
• R-Value Free: 0.339 
• R-Value Work: 0.283 
• R-Value Observed: 0.286 

Literature

Structure of the human glucagon class B G-protein-coupled receptor.

Siu, F.Y., He, M., de Graaf, C., Han, G.W., Yang, D., Zhang, Z., Zhou, C., Xu, Q., Wacker, D., Joseph, J.S., Liu, W., Lau, J., Cherezov, V., Katritch, V., Wang, M.W., Stevens, R.C.

(2013) Nature 499: 444-449

• PubMed: 23863937 
• DOI: 10.1038/nature12393
• Primary Citation of Related Structures:  
  4L6R


• PubMed Abstract: 
  

Binding of the glucagon peptide to the glucagon receptor (GCGR) triggers the release of glucose from the liver during fasting; thus GCGR plays an important role in glucose homeostasis. Here we report the crystal structure of the seven transmembrane helical domain of human GCGR at 3.4 Å resolution, complemented by extensive site-specific mutagenesis, and a hybrid model of glucagon bound to GCGR to understand the molecular recognition of the receptor for its native ligand. Beyond the shared seven transmembrane fold, the GCGR transmembrane domain deviates from class A G-protein-coupled receptors with a large ligand-binding pocket and the first transmembrane helix having a 'stalk' region that extends three alpha-helical turns above the plane of the membrane. The stalk positions the extracellular domain (~12 kilodaltons) relative to the membrane to form the glucagon-binding site that captures the peptide and facilitates the insertion of glucagon's amino terminus into the seven transmembrane domain.

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Organizational Affiliation: 

Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Soluble cytochrome b562 and Glucagon receptor chimera	A	425	Escherichia coli, Homo sapiens This entity is chimeric	Mutation(s): 3  Gene Names: cybC, GCGR_Human, GCGR Membrane Entity: Yes
UniProt & NIH Common Fund Data Resources
Find proteins for P0ABE7 (Escherichia coli) Explore P0ABE7  Go to UniProtKB:  P0ABE7
Find proteins for P47871 (Homo sapiens) Explore P47871  Go to UniProtKB:  P47871
PHAROS:  P47871 GTEx:  ENSG00000215644

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PEG	B [auth A]	DI(HYDROXYETHYL)ETHER C4 H10 O3 MTHSVFCYNBDYFN-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.30 Å
• R-Value Free: 0.339 
• R-Value Work: 0.283 
• R-Value Observed: 0.286 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 56.615	α = 90
b = 66.651	β = 90
c = 163.331	γ = 90

Software Package:

Software Name	Purpose
Blu-Ice	data collection
PHASER	phasing
BUSTER	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-06-12 
• Released Date: 2013-07-24 
Deposition Author(s): Siu, F.Y., He, M., de Graaf, C., Han, G.W., Yang, D., Zhang, Z., Zhou, C., Xu, Q., Wacker, D., Joseph, J.S., Liu, W., Lau, J., Cherezov, V., Katritch, V., Wang, M.W., Stevens, R.C., GPCR Network (GPCR)

Revision History  

• Version 1.0: 2013-07-24
  Type: Initial release
  
• Version 1.1: 2013-07-31
  Changes: Database references
• Version 1.2: 2013-08-07
  Changes: Database references
• Version 1.3: 2017-08-16
  Changes: Refinement description, Source and taxonomy
• Version 1.4: 2017-11-15
  Changes: Refinement description