Substrate choice of membrane-type 1 matrix metalloproteinase is dictated by tissue inhibitor of metalloproteinase-2 levels.
Although tissue inhibitor of metalloproteinase-2 (TIMP-2) is known to be not only an inhibitor of matrix metalloproteinases (MMP) but also a cofactor for membrane-type 1 MMP (MT1-MMP)-mediated MMP-2 activation, it is still unclear how TIMP-2 regulates MMP-2 activation and cleavage of substrates by MT1-MMP. In the present study we examined the levels of cell-surface MT1-MMP, MMP-2 activation and cleavage of MT1-MMP substrates in 293T cells transfected with the MT1-MMP and TIMP-2 genes. Co-expression of TIMP-2 at an appropriate level increased the level of cell-surface MT1-MMP, both the TIMP-2-bound and free forms, and generated processed MMP-2 with gelatin-degrading activity. In contrast, MT1-MMP substrates testican-1 and syndecan-1 were cleaved by the cells expressing MT1-MMP, which was inhibited by TIMP-2 even at levels that stimulate MMP-2 activation. These results suggest that TIMP-2 environment determines MT1-MMP substrate choice between direct cleavage of its own substrates and MMP-2 activation.
Kudo
Tomoya
T
Department of Molecular Virology and Oncology, Cancer Research Institute, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan.
Takino
Takahisa
T
Miyamori
Hisashi
H
Thompson
Erik W
EW
Sato
Hiroshi
H
D002460:Cell Line; D004789:Enzyme Activation; D006801:Humans; D053511:Matrix Metalloproteinase 14 / Q000096:biosynthesis* / Q000235:genetics; D011509:Proteoglycans / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism*; D053668:Syndecan-1 / Q000378:metabolism; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
D011509:Proteoglycans; D011994:Recombinant Proteins; C508241:SDC1 protein, human; C504369:SPOCK1 protein, human; D053668:Syndecan-1; D019716:Tissue Inhibitor of Metalloproteinase-2; D053511:Matrix Metalloproteinase 14