MT1-MMP ON THE CELL-SURFACE CAUSES FOCAL DEGRADATION OF GELATIN FILMS

The membrane-type matrix metalloproteinases (MT-MMPs) are a subclass o f the matrix metalloproteinase (MMP) family which uniquely possess a C -terminal transmembrane domain and are initiators of an activation cas cade for progelatinase A (MMP-2), Recent studies have shown that they can also efficiently directly degrade a number of matrix macromolecule s, We now show that cells expressing MT1-MMP on their cell surfaces ca use subjacent proteolysis of a gelatin film and that this proteolysis is inhibited by TIMP-2 but not by TIMP-1. These data indicate that exp ression of MT1-MMP on the cell surface may lead to both progelatinase A activation and extracellular matrix degradation. (C) 1998 Federation of European Biochemical Societies.