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1b0g
From Proteopedia
CLASS I HISTOCOMPATIBILITY ANTIGEN (HLA-A2.1)/BETA 2-MICROGLOBULIN/PEPTIDE P1049 COMPLEX
Overview
The T cell receptor (TCR), from a xeno-reactive murine cytotoxic T lymphocyte clone AHIII12.2, recognizes murine H-2Db complexed with peptide p1027 (FAPGVFPYM), as well as human HLA-A2.1 complexed with peptide p1049 (ALWGFFPVL). A commonly proposed model (the molecular mimicry model) used to explain TCR cross-reactivity suggests that the molecular surfaces of the recognized complexes are similar in shape, charge, or both, in spite of the primary sequence differences. To examine the mechanism of xeno-reactivity of AHIII12.2, we have determined the crystal structures of A2/p1049 and Db/p1027 to 2.5 A and 2.8 A resolution, respectively. The crystal structures show that the TCR footprint regions of the two class I complexes are significantly different in shape and charge. We propose that rather than simple molecular mimicry, unpredictable arrays of common and differential contacts on the two class I complexes are used for their recognition by the same TCR.
About this Structure
1B0G is a Protein complex structure of sequences from Homo sapiens. This structure supersedes the now removed PDB entry 1a9k. Full crystallographic information is available from OCA.
Reference
Structural evidence of T cell xeno-reactivity in the absence of molecular mimicry., Zhao R, Loftus DJ, Appella E, Collins EJ, J Exp Med. 1999 Jan 18;189(2):359-70. PMID:9892618 Page seeded by OCA on Fri May 2 10:55:10 2008
