3BES

Structure of a Poxvirus ifngbp/ifng Complex

Summary for 3BES

• Entry DOI: 10.2210/pdb3bes/pdb
• Descriptor: Interferon gamma, Interferon-gamma binding protein C4R, beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (6 entities in total)
• Functional Keywords: ectromelia virus, orthopoxvirus, interferon, protein complex, antiviral defense, cytokine, glycoprotein, receptor, immune system
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 2
• Total formula weight: 46150.79

Authors

Nuara, A.A.,Walter, M.R. (deposition date: 2007-11-20, release date: 2008-02-12, Last modification date: 2024-10-30)

Primary citation

Nuara, A.A.,Walter, L.J.,Logsdon, N.J.,Yoon, S.I.,Jones, B.C.,Schriewer, J.M.,Buller, R.M.,Walter, M.R.
Structure and mechanism of IFN-gamma antagonism by an orthopoxvirus IFN-gamma-binding protein.
Proc.Natl.Acad.Sci.Usa, 105:1861-1866, 2008

PubMed Abstract: Ectromelia virus (ECTV) encodes an IFN-gamma-binding protein (IFN-gammaBP(ECTV)) that disrupts IFN-gamma signaling and its ability to induce an antiviral state within cells. IFN-gammaBP(ECTV) is an important virulence factor that is highly conserved (>90%) in all orthopoxviruses, including variola virus, the causative agent of smallpox. The 2.2-A crystal structure of the IFN-gammaBP(ECTV)/IFN-gamma complex reveals IFN-gammaBP(ECTV) consists of an IFN-gammaR1 ligand-binding domain and a 57-aa helix-turn-helix (HTH) motif that is structurally related to the transcription factor TFIIA. The HTH motif forms a tetramerization domain that results in an IFN-gammaBP(ECTV)/IFN-gamma complex containing four IFN-gammaBP(ECTV) chains and two IFN-gamma dimers. The structure, combined with biochemical and cell-based assays, demonstrates that IFN-gammaBP(ECTV) tetramers are required for efficient IFN-gamma antagonism.

PubMed: 18252829
DOI: 10.1073/pnas.0705753105

Experimental method

X-RAY DIFFRACTION (2.2 Å)