@entity27624 ( @entity27624 ), a component released by normal @entity1 fibroblasts into culture medium, forms covalent linkages with @entity556 (Th) and the urinary plasminogen activator urokinase, apparently with their catalytic site serines. The present studies explored the function of @entity27624 by examining the interaction of protease- @entity27624 complexes with @entity1 fibroblasts and the consequences of this interaction. Th- @entity27624 and urokinase- @entity27624 complexes bind to cells via the @entity27624 portion of the complexes. The binding is selectively inhibited by heparin. Because @entity27624 has a heparin-binding site, this indicates that protease- @entity27624 complexes might bind to a cellular heparin-like site. After binding, the complexes are internalized. By inhibiting endocytosis with @entity11892 , which does not affect cellular binding of Th- @entity27624 complexes, we showed that complexes must be internalized before they are degraded. Kinetic analysis of internalization and degradation of Th- @entity27624 showed that complexes are internalized more rapidly than they dissociate from the cell surface; by 120 min of incubation at 37 degrees C most cell-bound Th- @entity27624 complexes are degraded to @entity1522 . The results are summarized in a model showing how @entity27624 mediates the cellular binding, internalization, and degradation of @entity563 proteases through formation of protease- @entity27624 complexes. This series of events may be involved in the regulation of @entity563 protease activity at the cell surface and in the extracellular environment.

Released protease-nexin regulates cellular binding, internalization, and degradation of XXXX proteases.

@entity1 :: ('9606', 'Species') :: ['human'] @entity27624 :: ('MESH:C566273', 'Disease') :: ['PN', 'Protease-nexin'] @entity1522 :: ('CHEBI:33709', 'Chemical') :: ['amino acids'] @entity556 :: ('2147', 'Gene') :: ['thrombin'] @entity11892 :: ('MESH:C029341', 'Chemical') :: ['phenylarsine oxide'] @entity563 :: ('CHEBI:17822', 'Chemical') :: ['serine']
@entity563 :: (CHEBI:17822,Chemical) :: ['serine']
