The human type I interferon receptor. NMR structure reveals the molecular basis of ligand binding.Chill, J.H., Quadt, S.R., Levy, R., Schreiber, G., Anglister, J.
(2003) Structure 11: 791-802
- PubMed: 12842042
- DOI: https://doi.org/10.1016/s0969-2126(03)00120-5
- Primary Citation of Related Structures:
- PubMed Abstract:
The potent antiviral and antiproliferative activities of human type I interferons (IFNs) are mediated by a single receptor comprising two subunits, IFNAR1 and IFNAR2. The structure of the IFNAR2 IFN binding ectodomain (IFNAR2-EC), the first helical cytokine receptor structure determined in solution, reveals the molecular basis for IFN binding. The atypical perpendicular orientation of its two fibronectin domains explains the lack of C domain involvement in ligand binding. A model of the IFNAR2-EC/IFNalpha2 complex based on double mutant cycle-derived constraints uncovers an extensive and predominantly aliphatic hydrophobic patch on the receptor that interacts with a matching hydrophobic surface of IFNalpha2. An adjacent motif of alternating charged side chains guides the two proteins into a tight complex. The binding interface may account for crossreactivity and ligand specificity of the receptor. This molecular description of IFN binding should be invaluable for study and design of IFN-based biomedical agents.
Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel.