1duz

File:1duz.jpg

spinqualitylabelsall models Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D load='1duz' size='350' frame='false' scene=
1duz, resolution 1.80Å
Coordinates:	save as pdb, mmCIF, xml

HUMAN CLASS I HISTOCOMPATIBILITY ANTIGEN (HLA-A 0201) IN COMPLEX WITH A NONAMERIC PEPTIDE FROM HTLV-1 TAX PROTEIN

Overview

The crystal structure of the human class I MHC molecule HLA-A2 complexed with of an octameric peptide, Tax8 (LFGYPVYV), from human T cell lymphotrophic virus-1 (HTLV-1) has been determined. This structure is compared with a newly refined, higher resolution (1.8 A) structure of HLA-A2 complexed with the nonameric Tax9 peptide (LLFGYPVYV) with one more N-terminal residue. Despite the absence of a peptide residue (P1) bound in the conserved N-terminal peptide-binding pocket of the Tax8/HLA-A2 complex, the structures of the two complexes are essentially identical. Water molecules in the Tax8 complex replace the terminal amino group of the Tax9 peptide and mediate a network of hydrogen bonds among the secondary structural elements at that end of the peptide-binding groove. Thermal denaturation measurements indicate that the Tax8 complex is much less stable, DeltaTm = 16 degrees C, than the Tax9 complex, but both can sensitize target cells for lysis by some Tax-specific CTL from HTLV-1 infected individuals. The absence of a P1 peptide residue is thus not enough to prevent formation of a "closed conformation" of the peptide-binding site. TCR affinity measurements and cytotoxic T cell assays indicate that the Tax8/HLA-A2 complex does not functionally cross-react with the A6-TCR-bearing T cell clone specific for Tax9/HLA-A2 complexes.

Disease

Known diseases associated with this structure: Abacavir hypersensitivity, susceptibility to OMIM:[142800], Ankylosing spondylitis, susceptibility to, 1 OMIM:[142800], Hypoproteinemia, hypercatabolic OMIM:[109700], Stevens-Johnson syndrome, susceptibility to OMIM:[142800]

About this Structure

1DUZ is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.

Reference

The structure and stability of an HLA-A*0201/octameric tax peptide complex with an empty conserved peptide-N-terminal binding site., Khan AR, Baker BM, Ghosh P, Biddison WE, Wiley DC, J Immunol. 2000 Jun 15;164(12):6398-405. PMID:10843695

Page seeded by OCA on Thu Mar 20 10:44:47 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA