Pentosan polysulfate increases affinity between ADAMTS-5 and TIMP-3 through formation of an electrostatically driven trimolecular complex.
The semi-synthetic sulfated polysaccharide PPS (pentosan polysulfate) increases affinity between the aggrecan-degrading ADAMTSs (adamalysins with thrombospondin motifs) and their endogenous inhibitor, TIMP (tissue inhibitor of metalloproteinases)-3. In the present study we demonstrate that PPS mediates the formation of a high-affinity trimolecular complex with ADAMTS-5 and TIMP-3. A TIMP-3 mutant that lacks extracellular-matrix-binding ability was insensitive to this affinity increase, and truncated forms of ADAMTS-5 that lack the Sp (spacer) domain had reduced PPS-binding ability and sensitivity to the affinity increase. PPS molecules composed of 11 or more saccharide units were 100-fold more effective than those of eight saccharide units, indicating the involvement of extended or multiple protein-interaction sites. The formation of a high-affinity trimolecular complex was completely abolished in the presence of 0.4 M NaCl. These results suggest that PPS enhances the affinity between ADAMTS-5 and TIMP-3 by forming electrostatically driven trimolecular complexes under physiological conditions.
The Kennedy Institute of Rheumatology, University of Oxford, 65 Aspenlea Road, Hammersmith, London W6 8LH, UK. linda.troeberg@kennedy.ox.ac.uk
Linda
L
Troeberg
Barbara
B
Mulloy
Peter
P
Ghosh
Meng-Huee
MH
Lee
Gillian
G
Murphy
Hideaki
H
Nagase
D051722:ADAM Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D000071116:ADAMTS5 Protein; D019943:Amino Acid Substitution; D002850:Chromatography, Gel; D057809:HEK293 Cells; D006801:Humans; D010426:Pentosan Sulfuric Polyester / Q000302:isolation & purification / Q000494:pharmacology*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D017384:Sequence Deletion; D012965:Sodium Chloride / Q000737:chemistry; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics
D011994:Recombinant Proteins; C088390:TIMP3 protein, human; D019717:Tissue Inhibitor of Metalloproteinase-3; D010426:Pentosan Sulfuric Polyester; D012965:Sodium Chloride; D051722:ADAM Proteins; D000071116:ADAMTS5 Protein; C121532:ADAMTS5 protein, human