4PV8

Crystal Structure of H2Kb-Q600F complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.31 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.170 
  • R-Value Observed: 0.173 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Structural and functional correlates of enhanced antiviral immunity generated by heteroclitic CD8 T cell epitopes.

Trujillo, J.A.Gras, S.Twist, K.A.Croft, N.P.Channappanavar, R.Rossjohn, J.Purcell, A.W.Perlman, S.

(2014) J Immunol 192: 5245-5256

  • DOI: https://doi.org/10.4049/jimmunol.1400111
  • Primary Citation of Related Structures:  
    4PV8, 4PV9

  • PubMed Abstract: 

    Peptides that bind poorly to MHC class I molecules often elicit low-functional avidity T cell responses. Peptide modification by altering the anchor residue facilitates increased binding affinity and may elicit T cells with increased functional avidity toward the native epitope ("heteroclitic"). This augmented MHC binding is likely to increase the half-life and surface density of the heteroclitic complex, but precisely how this enhanced T cell response occurs in vivo is not known. Furthermore, the ideal heteroclitic epitope will elicit T cell responses that completely cross-react with the native epitope, maximizing protection and minimizing undesirable off-target effects. Such epitopes have been difficult to identify. In this study, using mice infected with a murine coronavirus that encodes epitopes that elicit high (S510, CSLWNGPHL)- and low (S598, RCQIFANI)-functional avidity responses, we show that increased expression of peptide S598 but not S510 generated T cells with enhanced functional avidity. Thus, immune responses can be augmented toward T cell epitopes with low functional avidity by increasing Ag density. We also identified a heteroclitic epitope (RCVIFANI) that elicited a T cell response with nearly complete cross-reactivity with native epitope and demonstrated increased MHC/peptide abundance compared with native S598. Structural and thermal melt analyses indicated that the Q600V substitution enhanced stability of the peptide/MHC complex without greatly altering the antigenic surface, resulting in highly cross-reactive T cell responses. Our data highlight that increased peptide/MHC complex display contributes to heteroclitic epitope efficacy and describe parameters for maximizing immune responses that cross-react with the native epitope.


  • Organizational Affiliation

    Interdisciplinary Program in Immunology, University of Iowa, Iowa City, IA 52242;


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
H-2 class I histocompatibility antigen, K-B alpha chain
A, C
278Mus musculusMutation(s): 0 
Gene Names: H2-K1H2-K
UniProt
Find proteins for P01901 (Mus musculus)
Explore P01901 
Go to UniProtKB:  P01901
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP01901
Sequence Annotations
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Beta-2-microglobulin
B, D
99Mus musculusMutation(s): 0 
Gene Names: B2m
UniProt & NIH Common Fund Data Resources
Find proteins for P01887 (Mus musculus)
Explore P01887 
Go to UniProtKB:  P01887
IMPC:  MGI:88127
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP01887
Sequence Annotations
Expand
  • Reference Sequence

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
S598 peptide modified Q600F
E, F
8N/AMutation(s): 0 
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
ABA
Query on ABA
E, F
L-PEPTIDE LINKINGC4 H9 N O2ALA
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.31 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.170 
  • R-Value Observed: 0.173 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 66.46α = 90
b = 90.99β = 111.65
c = 89.61γ = 90
Software Package:
Software NamePurpose
XSCALEdata scaling
PHASERphasing
BUSTER-TNTrefinement
PDB_EXTRACTdata extraction
Blu-Icedata collection
XDSdata reduction
BUSTERrefinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-04-23
    Type: Initial release
  • Version 1.1: 2014-06-18
    Changes: Database references
  • Version 1.2: 2017-11-22
    Changes: Advisory, Refinement description
  • Version 1.3: 2023-09-20
    Changes: Advisory, Data collection, Database references, Derived calculations, Refinement description
  • Version 1.4: 2023-12-06
    Changes: Data collection