4LF3

Inhibitory Mechanism of an Allosteric Antibody Targeting the Glucagon Receptor


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.73 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.209 
  • R-Value Observed: 0.212 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Inhibitory mechanism of an allosteric antibody targeting the glucagon receptor.

Mukund, S.Shang, Y.Clarke, H.J.Madjidi, A.Corn, J.E.Kates, L.Kolumam, G.Chiang, V.Luis, E.Murray, J.Zhang, Y.Hotzel, I.Koth, C.M.Allan, B.B.

(2013) J Biol Chem 288: 36168-36178

  • DOI: 10.1074/jbc.M113.496984
  • Primary Citation of Related Structures:  
    4LEX, 4LF3

  • PubMed Abstract: 
  • Elevated glucagon levels and increased hepatic glucagon receptor (GCGR) signaling contribute to hyperglycemia in type 2 diabetes. We have identified a monoclonal antibody that inhibits GCGR, a class B G-protein coupled receptor (GPCR), through a unique allosteric mechanism ...

    Elevated glucagon levels and increased hepatic glucagon receptor (GCGR) signaling contribute to hyperglycemia in type 2 diabetes. We have identified a monoclonal antibody that inhibits GCGR, a class B G-protein coupled receptor (GPCR), through a unique allosteric mechanism. Receptor inhibition is mediated by the binding of this antibody to two distinct sites that lie outside of the glucagon binding cleft. One site consists of a patch of residues that are surface-exposed on the face of the extracellular domain (ECD) opposite the ligand-binding cleft, whereas the second binding site consists of residues in the αA helix of the ECD. A docking model suggests that the antibody does not occlude the ligand-binding cleft. We solved the crystal structure of GCGR ECD containing a naturally occurring G40S mutation and found a shift in the register of the αA helix that prevents antibody binding. We also found that alterations in the αA helix impact the normal function of GCGR. We present a model for the allosteric inhibition of GCGR by a monoclonal antibody that may form the basis for the development of allosteric modulators for the treatment of diabetes and other class B GPCR-related diseases.


    Organizational Affiliation

    From the Departments of Structural Biology.



Macromolecules
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Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Fab heavy chainA, D214Mus musculusMutation(s): 0 
Gene Names: Anti GCGR mAb
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Protein Feature View
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  • Reference Sequence
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Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Fab light chainB, E231Mus musculusMutation(s): 0 
Gene Names: Anti GCGR mAb
Entity Groups  
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Protein Feature View
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  • Reference Sequence
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Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
Glucagon receptorC, F95Homo sapiensMutation(s): 1 
Gene Names: GCGR
UniProt & NIH Common Fund Data Resources
Find proteins for P47871 (Homo sapiens)
Explore P47871 
Go to UniProtKB:  P47871
PHAROS:  P47871
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP47871
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.73 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.209 
  • R-Value Observed: 0.212 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 104.928α = 90
b = 62.777β = 106.04
c = 116.432γ = 90
Software Package:
Software NamePurpose
MOSFLMdata reduction
SCALAdata scaling
PHASERphasing
PHENIXrefinement
PDB_EXTRACTdata extraction
ADSCdata collection

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2013-11-13
    Type: Initial release
  • Version 1.1: 2013-11-27
    Changes: Database references
  • Version 1.2: 2014-01-01
    Changes: Database references