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1k2d
From Proteopedia
Crystal structure of the autoimmune MHC class II I-Au complexed with myelin basic protein 1-11 at 2.2A
Overview
Murine experimental allergic encephalomyelitis (EAE) is a useful model for the demyelinating, autoimmune disease multiple sclerosis. In the EAE system, the immunodominant N-terminal epitope of myelin basic protein (MBP) is an unusually short, weakly binding peptide antigen which elicits highly biased TCR chain usage. In the 2.2 A crystal structure of I-A(u)/MBP1-11 complex, only MBP residues 1-7 are bound toward one end of the peptide binding cleft. The fourth residue of MBP1-11 is located in an incompatible p6 pocket of I-A(u), thus explaining the short half-life of I-A(u) complexed with Ac1-11. MBP peptides extended at the C terminus of Ac1-11 result in dramatic affinity increases, likely attributed to register shifting to a higher affinity cryptic epitope, which could potentially mask the presentation of the immunodominant MBP1-11 peptide during thymic education.
About this Structure
1K2D is a Protein complex structure of sequences from Mus musculus. Full crystallographic information is available from OCA.
Reference
Structural snapshot of aberrant antigen presentation linked to autoimmunity: the immunodominant epitope of MBP complexed with I-Au., He XL, Radu C, Sidney J, Sette A, Ward ES, Garcia KC, Immunity. 2002 Jul;17(1):83-94. PMID:12150894 Page seeded by OCA on Fri May 2 22:12:56 2008
