1syv

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Template:STRUCTURE 1syv

HLA-B*4405 complexed to the dominant self ligand EEFGRAYGF

Contents 1 Overview 2 Disease 3 About this Structure 4 Reference

Overview

HLA class I polymorphism creates diversity in epitope specificity and T cell repertoire. We show that HLA polymorphism also controls the choice of Ag presentation pathway. A single amino acid polymorphism that distinguishes HLA-B*4402 (Asp116) from B*4405 (Tyr116) permits B*4405 to constitutively acquire peptides without any detectable incorporation into the transporter associated with Ag presentation (TAP)-associated peptide loading complex even under conditions of extreme peptide starvation. This mode of peptide capture is less susceptible to viral interference than the conventional loading pathway used by HLA-B*4402 that involves assembly of class I molecules within the peptide loading complex. Thus, B*4402 and B*4405 are at opposite extremes of a natural spectrum in HLA class I dependence on the PLC for Ag presentation. These findings unveil a new layer of MHC polymorphism that affects the generic pathway of Ag loading, revealing an unsuspected evolutionary trade-off in selection for optimal HLA class I loading versus effective pathogen evasion.

Disease

Known disease associated with this structure: Hypoproteinemia, hypercatabolic OMIM:[109700]

About this Structure

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

Reference

Natural HLA class I polymorphism controls the pathway of antigen presentation and susceptibility to viral evasion., Zernich D, Purcell AW, Macdonald WA, Kjer-Nielsen L, Ely LK, Laham N, Crockford T, Mifsud NA, Bharadwaj M, Chang L, Tait BD, Holdsworth R, Brooks AG, Bottomley SP, Beddoe T, Peh CA, Rossjohn J, McCluskey J, J Exp Med. 2004 Jul 5;200(1):13-24. Epub 2004 Jun 28. PMID:15226359 Page seeded by OCA on Sat May 3 09:17:31 2008