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Crystal structure of a complete ternary complex of TCR, superantigen and peptide-MHC.

ABSTRACT: 'Superantigens' (SAgs) trigger the massive activation of T cells by simultaneous interactions with MHC and TCR receptors, leading to human diseases. Here we present the first crystal structure, at 2.5-A resolution, of a complete ternary complex between a SAg and its two receptors, HLA-DR1/HA and TCR. The most striking finding is that the SAg Mycoplasma arthritidis mitogen, unlike others, has direct contacts not only with TCR Vbeta but with TCR Valpha.

SUBMITTER: Wang L

PROVIDER: S-EPMC3923521 | biostudies-literature | 2007 Feb

REPOSITORIES: biostudies-literature

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Crystal structure of a complete ternary complex of TCR, superantigen and peptide-MHC.

Wang Limin L Zhao Yiwei Y Li Zhong Z Guo Yi Y Jones Lindsay L LL Kranz David M DM Mourad Walid W Li Hongmin H

Nature structural & molecular biology 20070114 2

'Superantigens' (SAgs) trigger the massive activation of T cells by simultaneous interactions with MHC and TCR receptors, leading to human diseases. Here we present the first crystal structure, at 2.5-A resolution, of a complete ternary complex between a SAg and its two receptors, HLA-DR1/HA and TCR. The most striking finding is that the SAg Mycoplasma arthritidis mitogen, unlike others, has direct contacts not only with TCR Vbeta but with TCR Valpha. ...[more]

PMID: 17220897

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