3OSK

Crystal structure of human CTLA-4 apo homodimer


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 
    0.275 (Depositor), 0.270 (DCC) 
  • R-Value Work: 
    0.200 (Depositor), 0.190 (DCC) 
  • R-Value Observed: 
    0.203 (Depositor) 

Starting Model: experimental
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Ligand Structure Quality Assessment 

Created with Raphaël 2.3.0Worse 01 BetterLigand structure goodness of fit to experimental dataBest fitted NAGClick on this verticalbar to view details

This is version 1.5 of the entry. See complete history


Literature

Rigid-body ligand recognition drives cytotoxic T-lymphocyte antigen 4 (CTLA-4) receptor triggering

Yu, C.Sonnen, A.F.-P.George, R.Dessailly, B.H.Stagg, L.J.Evans, E.J.Orengo, C.A.Stuart, D.I.Ladbury, J.E.Ikemizu, S.Gilbert, R.J.C.Davis, S.J.

(2011) J Biol Chem 286: 6685-6696

  • DOI: https://doi.org/10.1074/jbc.M110.182394
  • Primary Citation of Related Structures:  
    3OSK

  • PubMed Abstract: 

    The inhibitory T-cell surface-expressed receptor, cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), which belongs to the class of cell surface proteins phosphorylated by extrinsic tyrosine kinases that also includes antigen receptors, binds the related ligands, B7-1 and B7-2, expressed on antigen-presenting cells. Conformational changes are commonly invoked to explain ligand-induced "triggering" of this class of receptors. Crystal structures of ligand-bound CTLA-4 have been reported, but not the apo form, precluding analysis of the structural changes accompanying ligand binding. The 1.8-Å resolution structure of an apo human CTLA-4 homodimer emphasizes the shared evolutionary history of the CTLA-4/CD28 subgroup of the immunoglobulin superfamily and the antigen receptors. The ligand-bound and unbound forms of both CTLA-4 and B7-1 are remarkably similar, in marked contrast to B7-2, whose binding to CTLA-4 has elements of induced fit. Isothermal titration calorimetry reveals that ligand binding by CTLA-4 is enthalpically driven and accompanied by unfavorable entropic changes. The similarity of the thermodynamic parameters determined for the interactions of CTLA-4 with B7-1 and B7-2 suggests that the binding is not highly specific, but the conformational changes observed for B7-2 binding suggest some level of selectivity. The new structure establishes that rigid-body ligand interactions are capable of triggering CTLA-4 phosphorylation by extrinsic kinase(s).


  • Organizational Affiliation

    Nuffield Department of Clinical Medicine and MRC Human Immunology Unit, The University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DU, United Kingdom.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Cytotoxic T-lymphocyte protein 4
A, B
130Homo sapiensMutation(s): 0 
Gene Names: CD152CTLA4
UniProt & NIH Common Fund Data Resources
Find proteins for P16410 (Homo sapiens)
Explore P16410 
Go to UniProtKB:  P16410
PHAROS:  P16410
GTEx:  ENSG00000163599 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP16410
Glycosylation
Glycosylation Sites: 1Go to GlyGen: P16410-1
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free:  0.275 (Depositor), 0.270 (DCC) 
  • R-Value Work:  0.200 (Depositor), 0.190 (DCC) 
  • R-Value Observed: 0.203 (Depositor) 
Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 43.864α = 90
b = 51.457β = 90
c = 102.849γ = 90
Software Package:
Software NamePurpose
HKL-3000data collection
PHASERphasing
PHENIXrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

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Ligand Structure Quality Assessment 

Created with Raphaël 2.3.0Worse 01 BetterLigand structure goodness of fit to experimental dataBest fitted NAGClick on this verticalbar to view details

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2010-12-08
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2014-02-05
    Changes: Database references
  • Version 1.3: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Data collection, Database references, Derived calculations, Structure summary
  • Version 1.4: 2023-11-01
    Changes: Data collection, Database references, Refinement description, Structure summary
  • Version 1.5: 2024-10-30
    Changes: Structure summary