1o7z
CRYSTAL STRUCTURE OF IP-10 T-FORM
OverviewOverview
We have determined the structure of wild-type IP-10 from three crystal forms. The crystals provide eight separate models of the IP-10 chain, all differing substantially from a monomeric IP-10 variant examined previously by NMR spectroscopy. In each crystal form, IP-10 chains form conventional beta sheet dimers, which, in turn, form a distinct tetrameric assembly. The M form tetramer is reminiscent of platelet factor 4, whereas the T and H forms feature a novel twelve-stranded beta sheet. Analytical ultracentrifugation indicates that, in free solution, IP-10 exists in a monomer-dimer equilibrium with a dissociation constant of 9 microM. We propose that the tetrameric structures may represent species promoted by the binding of glycosaminoglycans. The binding sites for several IP-10-neutralizing mAbs have also been mapped.
About this StructureAbout this Structure
1O7Z is a Single protein structure. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structures of oligomeric forms of the IP-10/CXCL10 chemokine., Swaminathan GJ, Holloway DE, Colvin RA, Campanella GK, Papageorgiou AC, Luster AD, Acharya KR, Structure. 2003 May;11(5):521-32. PMID:12737818 Page seeded by OCA on Sat May 3 03:30:07 2008