1jl4
From Proteopedia
| Line 1: | Line 1: | ||
| - | [[Image:1jl4.jpg|left|200px]] | + | [[Image:1jl4.jpg|left|200px]] |
| - | + | ||
| - | '''CRYSTAL STRUCTURE OF THE HUMAN CD4 N-TERMINAL TWO DOMAIN FRAGMENT COMPLEXED TO A CLASS II MHC MOLECULE''' | + | {{Structure |
| + | |PDB= 1jl4 |SIZE=350|CAPTION= <scene name='initialview01'>1jl4</scene>, resolution 4.3Å | ||
| + | |SITE= | ||
| + | |LIGAND= | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''CRYSTAL STRUCTURE OF THE HUMAN CD4 N-TERMINAL TWO DOMAIN FRAGMENT COMPLEXED TO A CLASS II MHC MOLECULE''' | ||
| + | |||
==Overview== | ==Overview== | ||
The structural basis of the interaction between the CD4 coreceptor and a class II major histocompatibility complex (MHC) is described. The crystal structure of a complex containing the human CD4 N-terminal two-domain fragment and the murine I-A(k) class II MHC molecule with associated peptide (pMHCII) shows that only the "top corner" of the CD4 molecule directly contacts pMHCII. The CD4 Phe-43 side chain extends into a hydrophobic concavity formed by MHC residues from both alpha 2 and beta 2 domains. A ternary model of the CD4-pMHCII-T-cell receptor (TCR) reveals that the complex appears V-shaped with the membrane-proximal pMHCII at the apex. This configuration excludes a direct TCR-CD4 interaction and suggests how TCR and CD4 signaling is coordinated around the antigenic pMHCII complex. Human CD4 binds to HIV gp120 in a manner strikingly similar to the way in which CD4 interacts with pMHCII. Additional contacts between gp120 and CD4 give the CD4-gp120 complex a greater affinity. Thus, ligation of the viral envelope glycoprotein to CD4 occludes the pMHCII-binding site on CD4, contributing to immunodeficiency. | The structural basis of the interaction between the CD4 coreceptor and a class II major histocompatibility complex (MHC) is described. The crystal structure of a complex containing the human CD4 N-terminal two-domain fragment and the murine I-A(k) class II MHC molecule with associated peptide (pMHCII) shows that only the "top corner" of the CD4 molecule directly contacts pMHCII. The CD4 Phe-43 side chain extends into a hydrophobic concavity formed by MHC residues from both alpha 2 and beta 2 domains. A ternary model of the CD4-pMHCII-T-cell receptor (TCR) reveals that the complex appears V-shaped with the membrane-proximal pMHCII at the apex. This configuration excludes a direct TCR-CD4 interaction and suggests how TCR and CD4 signaling is coordinated around the antigenic pMHCII complex. Human CD4 binds to HIV gp120 in a manner strikingly similar to the way in which CD4 interacts with pMHCII. Additional contacts between gp120 and CD4 give the CD4-gp120 complex a greater affinity. Thus, ligation of the viral envelope glycoprotein to CD4 occludes the pMHCII-binding site on CD4, contributing to immunodeficiency. | ||
| - | |||
| - | ==Disease== | ||
| - | Known diseases associated with this structure: CD4 lymphocyte deficiency OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=186940 186940]], Lupus erythematosus, susceptibility to OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=186940 186940]] | ||
==About this Structure== | ==About this Structure== | ||
| - | 1JL4 is a [ | + | 1JL4 is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus], [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JL4 OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal structure of the human CD4 N-terminal two-domain fragment complexed to a class II MHC molecule., Wang JH, Meijers R, Xiong Y, Liu JH, Sakihama T, Zhang R, Joachimiak A, Reinherz EL, Proc Natl Acad Sci U S A. 2001 Sep 11;98(19):10799-804. Epub 2001 Sep 4. PMID:[http:// | + | Crystal structure of the human CD4 N-terminal two-domain fragment complexed to a class II MHC molecule., Wang JH, Meijers R, Xiong Y, Liu JH, Sakihama T, Zhang R, Joachimiak A, Reinherz EL, Proc Natl Acad Sci U S A. 2001 Sep 11;98(19):10799-804. Epub 2001 Sep 4. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/11535811 11535811] |
[[Category: Gallus gallus]] | [[Category: Gallus gallus]] | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
| Line 23: | Line 29: | ||
[[Category: protein-protein complex]] | [[Category: protein-protein complex]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 12:04:54 2008'' |
Revision as of 10:04, 20 March 2008
| |||||||
| , resolution 4.3Å | |||||||
|---|---|---|---|---|---|---|---|
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF THE HUMAN CD4 N-TERMINAL TWO DOMAIN FRAGMENT COMPLEXED TO A CLASS II MHC MOLECULE
Overview
The structural basis of the interaction between the CD4 coreceptor and a class II major histocompatibility complex (MHC) is described. The crystal structure of a complex containing the human CD4 N-terminal two-domain fragment and the murine I-A(k) class II MHC molecule with associated peptide (pMHCII) shows that only the "top corner" of the CD4 molecule directly contacts pMHCII. The CD4 Phe-43 side chain extends into a hydrophobic concavity formed by MHC residues from both alpha 2 and beta 2 domains. A ternary model of the CD4-pMHCII-T-cell receptor (TCR) reveals that the complex appears V-shaped with the membrane-proximal pMHCII at the apex. This configuration excludes a direct TCR-CD4 interaction and suggests how TCR and CD4 signaling is coordinated around the antigenic pMHCII complex. Human CD4 binds to HIV gp120 in a manner strikingly similar to the way in which CD4 interacts with pMHCII. Additional contacts between gp120 and CD4 give the CD4-gp120 complex a greater affinity. Thus, ligation of the viral envelope glycoprotein to CD4 occludes the pMHCII-binding site on CD4, contributing to immunodeficiency.
About this Structure
1JL4 is a Protein complex structure of sequences from Gallus gallus, Homo sapiens and Mus musculus. Full crystallographic information is available from OCA.
Reference
Crystal structure of the human CD4 N-terminal two-domain fragment complexed to a class II MHC molecule., Wang JH, Meijers R, Xiong Y, Liu JH, Sakihama T, Zhang R, Joachimiak A, Reinherz EL, Proc Natl Acad Sci U S A. 2001 Sep 11;98(19):10799-804. Epub 2001 Sep 4. PMID:11535811
Page seeded by OCA on Thu Mar 20 12:04:54 2008
