CELL MEMBRANE-BOUND PROTEASES - NOT ONLY PROTEOLYSIS

Ectopeptidases are widely distributed among various cell systems. Thei r expression on an appropriate cell type is finely regulated, reflecti ng the specific functional cell implications and engagement in defined physiological pathways. Protein turnover, ontogeny, inflammation, tis sue remodelling, cell migration and tumor invasion are among the many physiological and pathological events in which cell-surface proteases play a crucial role, both as effector as well as regulatory molecules. It has recently become clear that also non-catalytic effects of membr ane-bound proteases are of great importance in some biological regulat ions. They may generate specific signal transduction intracellularly, after reacting with certain target molecules. They may also play a piv otal role in cell-cell and cell-virus contact and recognition, as well as in binding to the extracellular matrix. This short review provides some insight into the multifunctional mechanisms attributed to cell m embrane-bound proteases.