title: Circular trimers of gelatinase B/matrix metalloproteinase-9 constitute a distinct population of functional enzyme molecules differentially regulated by tissue inhibitor of metalloproteinases-1.
abstract: Gelatinase B/matrix metalloproteinase-9 (MMP-9) (EC 3.4.24.35) cleaves many substrates and is produced by most cell types as a zymogen, proMMP-9, in complex with the tissue inhibitor of metalloproteinases-1 (TIMP-1). Natural proMMP-9 occurs as monomers, homomultimers and heterocomplexes, but our knowledge about the overall structure of proMMP-9 monomers and multimers is limited. We investigated biochemical, biophysical and functional characteristics of zymogen and activated forms of MMP-9 monomers and multimers. In contrast with a conventional notion of a dimeric nature of MMP-9 homomultimers, we demonstrate that these are reduction-sensitive trimers. Based on the information from electrophoresis, AFM and TEM, we generated a 3D structure model of the proMMP-9 trimer. Remarkably, the proMMP-9 trimers possessed a 50-fold higher affinity for TIMP-1 than the monomers. In vivo, this finding was reflected in a higher extent of TIMP-1 inhibition of angiogenesis induced by trimers compared with monomers. Our results show that proMMP-9 trimers constitute a novel structural and functional entity that is differentially regulated by TIMP-1.
authors.affiliation: *Laboratory of Immunobiology, Rega Institute for Medical Research, University of Leuven, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Vandooren
authors.affiliation: †Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Born
authors.affiliation: †Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Inna
authors.initials: I
authors.lastname: Solomonov
authors.affiliation: ‡Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037, U.S.A.
authors.forename: Ewa
authors.initials: E
authors.lastname: Zajac
authors.affiliation: §NIBRT GlycoScience Group, National Institute for Bioprocessing Research and Training, Fosters Avenue, Mount Merrion, Blackrock, Dublin 4, Ireland.
authors.forename: Radka
authors.initials: R
authors.lastname: Saldova
authors.affiliation: †Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Michael
authors.initials: M
authors.lastname: Senske
authors.affiliation: ║Cellular and Molecular Medicine Department, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), 28040 Madrid, Spain.
authors.forename: Estefanía
authors.initials: E
authors.lastname: Ugarte-Berzal
authors.affiliation: *Laboratory of Immunobiology, Rega Institute for Medical Research, University of Leuven, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Erik
authors.initials: E
authors.lastname: Martens
authors.affiliation: *Laboratory of Immunobiology, Rega Institute for Medical Research, University of Leuven, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Philippe E
authors.initials: PE
authors.lastname: Van den Steen
authors.affiliation: **Laboratory of Molecular Immunology, Rega Institute for Medical Research, University of Leuven, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Jo
authors.initials: J
authors.lastname: Van Damme
authors.affiliation: ║Cellular and Molecular Medicine Department, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), 28040 Madrid, Spain.
authors.forename: Angeles
authors.initials: A
authors.lastname: Garcia-Pardo
authors.affiliation: ††Laboratory of Medicinal Chemistry, Rega Institute for Medical Research, University of Leuven, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Matheus
authors.initials: M
authors.lastname: Froeyen
authors.affiliation: ‡Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037, U.S.A.
authors.forename: Elena I
authors.initials: EI
authors.lastname: Deryugina
authors.affiliation: ‡Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037, U.S.A.
authors.forename: James P
authors.initials: JP
authors.lastname: Quigley
authors.affiliation: ‡‡Department of Biomedicine, University of Aarhus, DK-8000 Aarhus C, Denmark.
authors.forename: Søren K
authors.initials: SK
authors.lastname: Moestrup
authors.affiliation: §NIBRT GlycoScience Group, National Institute for Bioprocessing Research and Training, Fosters Avenue, Mount Merrion, Blackrock, Dublin 4, Ireland.
authors.forename: Pauline M
authors.initials: PM
authors.lastname: Rudd
authors.affiliation: †Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Irit
authors.initials: I
authors.lastname: Sagi
authors.affiliation: *Laboratory of Immunobiology, Rega Institute for Medical Research, University of Leuven, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Ghislain
authors.initials: G
authors.lastname: Opdenakker
mesh_terms: D004792:Enzyme Precursors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D008958:Models, Molecular; D046912:Multiprotein Complexes / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D004792:Enzyme Precursors; D046912:Multiprotein Complexes; C560822:TIMP1 protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1; C120487:pro-matrix metalloproteinase 9; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9