title: ADAMTS1 mediates the release of antiangiogenic polypeptides from TSP1 and 2.
abstract: Matrix metalloproteases regulate both physiological and pathological events by processing matrix proteins and growth factors. ADAMTS1 in particular is required for normal ovulation and renal function and has been shown to modulate angiogenesis. Here we report that TSP1 and 2 are substrates of ADAMTS1. Using a combination of mass spectrometry and Edman degradation, we mapped the cleavage sites and characterized the biological relevance of these processing events. ADAMTS1 cleavage mediates the release of polypeptides from the trimeric structure of both TSP1 and 2 generating a pool of antiangiogenic fragments from matrix-bound thrombospondin. Using neo-epitope antibodies we confirmed that processing occurs during wound healing of wild-type mice. However, TSP1 proteolysis is decreased or absent in ADAMTS1 null mice; this is associated with delayed wound closure and increased angiogenic response. Finally, TSP1-/- endothelial cells revealed that the antiangiogenic response mediated by ADAMTS1 is greatly dependent on TSP1. These findings have unraveled a mechanistic explanation for the angiostatic functions attributed to ADAMTS1 and demonstrated in vivo processing of TSP1 under situations of tissue repair.
authors.affiliation: Department of Molecular, Cell and Developmental Biology, Molecular Biology Institute, Jonsson Comprehensive Cancer Center, University of California, Los Angeles, CA 90095, USA.
authors.forename: Nathan V
authors.initials: NV
authors.lastname: Lee
authors.forename: Makoto
authors.initials: M
authors.lastname: Sato
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Annis
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Loo
authors.forename: Lily
authors.initials: L
authors.lastname: Wu
authors.forename: Deane F
authors.initials: DF
authors.lastname: Mosher
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Iruela-Arispe
mesh_terms: D051722:ADAM Proteins / Q000235:genetics / Q000378:metabolism*; D000071097:ADAMTS1 Protein; D053674:Aggrecans / Q000378:metabolism; D000595:Amino Acid Sequence; D020533:Angiogenesis Inhibitors / Q000378:metabolism* / Q000494:pharmacology; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D018919:Neovascularization, Physiologic / Q000187:drug effects; D010446:Peptide Fragments / Q000378:metabolism* / Q000494:pharmacology; D051381:Rats; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D019700:Thrombospondin 1 / Q000235:genetics / Q000378:metabolism*; D019699:Thrombospondins / Q000235:genetics / Q000378:metabolism*; D014945:Wound Healing / Q000187:drug effects; D000099262:Thrombospondin 2
chemical_list: D051722:ADAM Proteins; D000071097:ADAMTS1 Protein; D053674:Aggrecans; D020533:Angiogenesis Inhibitors; D010446:Peptide Fragments; D011994:Recombinant Proteins; D019700:Thrombospondin 1; D019699:Thrombospondins; D000099262:Thrombospondin 2; C486323:Adamts1 protein, mouse