|1ilp, 20 NMR models ()|
CXCR-1 N-TERMINAL PEPTIDE BOUND TO INTERLEUKIN-8
BACKGROUND: Interactions between CXC chemokines (e.g. interleukin-8, IL-8) and their receptors (e.g. CXCR-1) have a key role in host defense and disease by attracting and upregulating neutrophils to sites of inflammation. The transmembrane nature of the receptor impedes structure-based understanding of ligand interactions. Linear peptides based on the N-terminal, extracellular portion of the receptor CXCR-1 do bind to IL-8, however, and inhibit the binding of IL-8 to the full-length receptor. RESULTS: The NMR solution structure of the complex formed between IL-8 and one such receptor-based peptide indicates that a cleft between a loop and a beta hairpin constitute part of the receptor interaction surface on IL-8. Nine residues from the C terminus of the receptor peptide (corresponding to Pro21-Pro29 of CXCR-1) occupy the cleft in an extended fashion. Intermolecular contacts are mostly hydrophobic and sidechain mediated. CONCLUSIONS: The results offer the first details at an atomic level of the interaction between a chemokine and its receptor. Consideration of other biochemical data allow extrapolation to a model for the interaction of IL-8 with the full-length receptor. In this model, the heparin-binding residues of IL-8 are exposed, thereby allowing presentation of the chemokine from endothelial cell-surface glycosaminoglycans. This first glimpse of how IL-8 binds to its receptor provides a foundation for the structure-based design of chemokine antagonists.
Structure of a CXC chemokine-receptor fragment in complex with interleukin-8., Skelton NJ, Quan C, Reilly D, Lowman H, Structure. 1999 Feb 15;7(2):157-68. PMID:10368283
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
About this Structure
- Skelton NJ, Quan C, Reilly D, Lowman H. Structure of a CXC chemokine-receptor fragment in complex with interleukin-8. Structure. 1999 Feb 15;7(2):157-68. PMID:10368283
- Ravindran A, Joseph PR, Rajarathnam K. Structural basis for differential binding of the interleukin-8 monomer and dimer to the CXCR1 N-domain: role of coupled interactions and dynamics. Biochemistry. 2009 Sep 22;48(37):8795-805. PMID:19681642 doi:10.1021/bi901194p