IMMUNOPURIFICATION AND CHARACTERIZATION OF A COLLAGENASE GELATINASE DOMAIN ISSUED FROM BASEMENT-MEMBRANE FIBRONECTIN/

The proteolytic potential of cellular fibronectin fragments issued fro m a basement membrane hydrolysate was investigated, Three different ge latinase activities (47, 43 and 37 kDa), located by gelatin zymography , were isolated using successively heparin-agarose, gelatin-agarose an d immunopurification with polyclonal antibodies directed against bovin e plasma fibronectin, These fragments were also characterized using a monoclonal antibody directed against the extra-domain EDA of cellular fibronectin as a probe, A collagenase activity, reliably indicated by the gelatin zymography pattern, was also found using MCA-Pro-Leu-Gly-L eu-DPA-Ala-Arg-NH2, the intramolecularly quenched fluorogenic substrat e of collagenases. From these results, cellular fibronectin was found to be able to exhibit a proteolytic function after limited proteolysis , This MMP-like function could be associated with tissue remodeling in both normal and pathological states, such as metastasis, angiogenesis and tissue repair.