Download MendeleyStructure and mechanism of IFN-gamma antagonism by an orthopoxvirus IFN-gamma-binding protein.
Nuara, A.A., Walter, L.J., Logsdon, N.J., Yoon, S.I., Jones, B.C., Schriewer, J.M., Buller, R.M., Walter, M.R.(2008) Proc Natl Acad Sci U S A 105: 1861-1866
- PubMed: 18252829
- DOI: https://doi.org/10.1073/pnas.0705753105
- Primary Citation of Related Structures:
3BES - 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.
Organizational Affiliation:
Center for Biophysical Sciences and Engineering, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
