3S5L

Crystal structure of CD4 mutant bound to HLA-DR1


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.268 
  • R-Value Work: 0.234 

Starting Models: experimental
View more details

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Affinity maturation of human CD4 by yeast surface display and crystal structure of a CD4-HLA-DR1 complex.

Wang, X.X.Li, Y.Yin, Y.Mo, M.Wang, Q.Gao, W.Wang, L.Mariuzza, R.A.

(2011) Proc Natl Acad Sci U S A 108: 15960-15965

  • DOI: https://doi.org/10.1073/pnas.1109438108
  • Primary Citation of Related Structures:  
    3S4S, 3S5L

  • PubMed Abstract: 

    Helper T-cell activation generally requires the coreceptor CD4, which binds MHC class II molecules. A remarkable feature of the CD4-MHC class II interaction is its exceptionally low affinity, which ranges from K(D) = ∼200 μM to >2 mM. Investigating the biological role of the much lower affinity of this interaction than those of other cell-cell recognition molecules will require CD4 mutants with enhanced binding to MHC class II for testing in models of T-cell development. To this end, we used in vitro-directed evolution to increase the affinity of human CD4 for HLA-DR1. A mutant CD4 library was displayed on the surface of yeast and selected using HLA-DR1 tetramers or monomers, resulting in isolation of a CD4 clone containing 11 mutations. Reversion mutagenesis showed that most of the affinity increase derived from just two substitutions, Gln40Tyr and Thr45Trp. A CD4 variant bearing these mutations bound HLA-DR1 with K(D) = 8.8 μM, compared with >400 μM for wild-type CD4. To understand the basis for improved affinity, we determined the structure of this CD4 variant in complex with HLA-DR1 to 2.4 Å resolution. The structure provides an atomic-level description of the CD4-binding site on MHC class II and reveals how CD4 recognizes highly polymorphic HLA-DR, -DP, and -DQ molecules by targeting invariant residues in their α2 and β2 domains. In addition, the CD4 mutants reported here constitute unique tools for probing the influence of CD4 affinity on T-cell activation and development.


  • Organizational Affiliation

    W. M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, MD 20850, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
HLA class II histocompatibility antigen, DR alpha chainA,
B [auth D]
182Homo sapiensMutation(s): 0 
Gene Names: HLA-DRA
UniProt & NIH Common Fund Data Resources
Find proteins for P01903 (Homo sapiens)
Explore P01903 
Go to UniProtKB:  P01903
PHAROS:  P01903
GTEx:  ENSG00000204287 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP01903
Sequence Annotations
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
HLA class II histocompatibility antigen DR beta chainC [auth B],
D [auth E]
193Homo sapiensMutation(s): 0 
Gene Names: HLA-DRB1
UniProt & NIH Common Fund Data Resources
Find proteins for P01911 (Homo sapiens)
Explore P01911 
Go to UniProtKB:  P01911
PHAROS:  P01911
GTEx:  ENSG00000196126 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP01911
Sequence Annotations
Expand
  • Reference Sequence

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
HA peptideE [auth C],
F
13Homo sapiensMutation(s): 0 
UniProt
Find proteins for P03437 (Influenza A virus (strain A/Aichi/2/1968 H3N2))
Explore P03437 
Go to UniProtKB:  P03437
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP03437
Sequence Annotations
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 4
MoleculeChains Sequence LengthOrganismDetailsImage
T-cell surface glycoprotein CD4
G, H
191Homo sapiensMutation(s): 4 
Gene Names: CD4
UniProt & NIH Common Fund Data Resources
Find proteins for P01730 (Homo sapiens)
Explore P01730 
Go to UniProtKB:  P01730
PHAROS:  P01730
GTEx:  ENSG00000010610 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP01730
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download Ideal Coordinates CCD File 
I [auth A]
J [auth D]
K [auth B]
L [auth B]
M [auth E]
I [auth A],
J [auth D],
K [auth B],
L [auth B],
M [auth E],
N [auth E],
O [auth E],
P [auth G],
Q [auth G],
R [auth H]
GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.268 
  • R-Value Work: 0.234 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 94.2α = 90
b = 119.7β = 90
c = 137.4γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
PHASERphasing
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

  • Released Date: 2011-09-21 
  • Deposition Author(s): Li, Y.

Revision History  (Full details and data files)

  • Version 1.0: 2011-09-21
    Type: Initial release
  • Version 1.1: 2011-11-16
    Changes: Database references
  • Version 1.2: 2023-09-13
    Changes: Data collection, Database references, Derived calculations, Refinement description, Source and taxonomy, Structure summary
  • Version 1.3: 2024-11-27
    Changes: Structure summary