title: Pericellular activation of proMMP-7 (promatrilysin-1) through interaction with CD151.
abstract: Matrix metalloproteinase-7 (MMP-7) (also known as matrilysin-1) is secreted as a proenzyme (proMMP-7) and plays a key role in the degradation of various extracellular matrix (ECM) and non-ECM molecules after activation. To identify the binding proteins related to proMMP-7 activation, a human lung cDNA library was screened by yeast two-hybrid system using proMMP-7 as bait. We identified a candidate molecule CD151, which is a member of the transmembrane 4 superfamily. Complex formation of proMMP-7 with CD151 was demonstrated by immunoprecipitation of the molecules from CaR-1 cells, a human rectal carcinoma cell line, expressing both proMMP-7 and CD151, and CD151 stable transfectants incubated with proMMP-7. Yeast two-hybrid assays using deletion mutants of proMMP-7 and CD151 suggested an interaction between the propeptide of proMMP-7 and the COOH-terminal extracellular loop of CD151. The binding activity of (125)I-labeled proMMP-7 to CD151 on the cell membranes was shown with CD151 stable transfectants. Laser-scanning confocal microscopy demonstrated that proMMP-7 colocalizes with CD151 on the cell membranes of CD151 stable transfectants and CaR-1 cells. In situ zymography using crosslinked carboxymethylated transferrin, a substrate of MMP-7, demonstrated proteinase activity on and around CD151 stable transfectants and CaR-1 cells, while the activity was abolished by their treatment with MMP inhibitors, anti-MMP-7 antibody or anti-CD151 antibody. In human lung adenocarcinoma tissues, colocalization of MMP-7 and CD151 was demonstrated on the carcinoma cells. Metalloproteinase activity was present in these tissues and could be inhibited by antibodies to MMP-7 or CD151. These data demonstrate for the first time that proMMP-7 is captured and activated on the cell membranes through interaction with CD151, and suggest the possibility that similar to the MT1-MMP/MMP-2 system, MMP-7 is involved in the pericellular activation mechanism mediated by CD151, a crucial step in proteolysis on the cell membranes under various pathophysiological conditions including cancer invasion and metastasis.
authors.affiliation: Department of Pathology, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Shiomi
authors.forename: Isao
authors.initials: I
authors.lastname: Inoki
authors.forename: Fumio
authors.initials: F
authors.lastname: Kataoka
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohtsuka
authors.forename: Gakuji
authors.initials: G
authors.lastname: Hashimoto
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Nemori
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Okada
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology* / Q000473:pathology; D019138:Antibodies, Blocking / Q000494:pharmacology; D015703:Antigens, CD / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology*; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005109:Extracellular Matrix / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology* / Q000473:pathology; D020783:Matrix Metalloproteinase 7 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D009361:Neoplasm Invasiveness / Q000503:physiopathology; D009362:Neoplasm Metastasis / Q000503:physiopathology; D012004:Rectal Neoplasms / Q000201:enzymology*; D060185:Tetraspanin 24; D014162:Transfection; D020798:Two-Hybrid System Techniques
chemical_list: D019138:Antibodies, Blocking; D015703:Antigens, CD; C554715:CD151 protein, human; D004791:Enzyme Inhibitors; D060185:Tetraspanin 24; D020783:Matrix Metalloproteinase 7