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Crystal structure of TNFalpha complexed with a poxvirus MHC-related TNF binding protein.

ABSTRACT: The poxvirus 2L protein binds tumor necrosis factor-alpha (TNFalpha) to inhibit host antiviral and immune responses. The 2.8-A 2L-TNFalpha structure reveals three symmetrically arranged 2L molecules per TNFalpha trimer. 2L resembles class I major histocompatibility complex (MHC) molecules but lacks a peptide-binding groove and beta2-microglobulin light chain. Overlap between the 2L and host TNF receptor-binding sites on TNFalpha rationalizes 2L inhibition of TNFalpha-TNF receptor interactions and prevention of TNFalpha-induced immune responses.

SUBMITTER: Yang Z

PROVIDER: S-EPMC2819277 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Crystal structure of TNFalpha complexed with a poxvirus MHC-related TNF binding protein.

Yang Zhiru Z West Anthony P AP Bjorkman Pamela J PJ

Nature structural & molecular biology 20091018 11

The poxvirus 2L protein binds tumor necrosis factor-alpha (TNFalpha) to inhibit host antiviral and immune responses. The 2.8-A 2L-TNFalpha structure reveals three symmetrically arranged 2L molecules per TNFalpha trimer. 2L resembles class I major histocompatibility complex (MHC) molecules but lacks a peptide-binding groove and beta2-microglobulin light chain. Overlap between the 2L and host TNF receptor-binding sites on TNFalpha rationalizes 2L inhibition of TNFalpha-TNF receptor interactions an ...[more]

PMID: 19838188

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