Rapid trafficking of membrane type 1-matrix metalloproteinase to the cell surface regulates progelatinase a activation.
Pericellular matrix degradation during cancer invasion and inflammation is dependent on activation of progelatinase A by membrane type 1-matrix metalloproteinase (MT1-MMP); a stoichiometric concentration of tissue inhibitor of metalloproteinase-2 (TIMP-2) is required. Activation of progelatinase A has generally been considered to be a slow process occurring as a result of enhanced expression of MT1-MMP. We herein report that ConA treatment of HT1080 fibrosarcoma cells is followed by MT1-MMP-induced activation of progelatinase A on the cell surface within 1 hour. Cell surface biotinylation, immunohistochemistry, and (125)I-labeled TIMP-2 binding to cell surface MT1-MMP were used to characterize the appearance and function of MT1-MMP on the plasma membrane. Treatment of HT1080 cells with ConA resulted in increased specific binding of (125)I-labeled TIMP-2 to cell surface receptors within 5 minutes. TIMP-2 binds almost exclusively to activated MT1-MMP on the surface of HT1080 cells. MT1-MMP function at the cell surface was also accelerated by treatment of cells with cytochalasin D, an inhibitor of actin filaments, PMA, a stimulator of protein kinase C, and bafilomycin A(1), an inhibitor of lysosome/endosome function. A functional pool of intracellular MT1-MMP available for trafficking to the cell surface was demonstrated by repetitive ConA stimulation. ConA-induced expression of MT1-MMP mRNA (Northern blot analysis) in HT1080 cells was a delayed event (>6 hours). These data suggest that presynthesized MT1-MMP is sorted to a transient storage compartment (trans-Golgi network/endosomes), where it is available for rapid trafficking to the plasma membrane and cell surface proteolytic activity.
Zucker
Stanley
S
Department of Research, Veterans Affairs Medical Center, Northport, New York, 11768, USA. s_zucker@yahoo.com
Hymowitz
Michelle
M
Conner
Cathleen E
CE
DiYanni
Elizabeth A
EA
Cao
Jian
J
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology*; D003208:Concanavalin A / Q000494:pharmacology; D015638:Cytochalasin D / Q000494:pharmacology; D004789:Enzyme Activation; D004792:Enzyme Precursors / Q000096:biosynthesis*; D005354:Fibrosarcoma / Q000201:enzymology; D016650:Fluorescein-5-isothiocyanate / Q000378:metabolism; D018093:Gelatinases / Q000096:biosynthesis*; D006801:Humans; D018942:Macrolides; D053504:Matrix Metalloproteinases, Membrane-Associated; D008666:Metalloendopeptidases / Q000096:biosynthesis* / Q000378:metabolism*; D021381:Protein Transport; D011956:Receptors, Cell Surface / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000201:enzymology
D000900:Anti-Bacterial Agents; D004792:Enzyme Precursors; D018942:Macrolides; D011956:Receptors, Cell Surface; D003208:Concanavalin A; D019716:Tissue Inhibitor of Metalloproteinase-2; D015638:Cytochalasin D; C040929:bafilomycin A1; D018093:Gelatinases; D053504:Matrix Metalloproteinases, Membrane-Associated; D008666:Metalloendopeptidases; C069860:progelatinase; D016650:Fluorescein-5-isothiocyanate; D013755:Tetradecanoylphorbol Acetate