Simultaneous activation and hepatocyte growth factor activator inhibitor 1-mediated inhibition of matriptase induced at activation foci in human mammary epithelial cells
| Autor: | Christelle Benaud, Robert B. Dickson, Ming-Shyue Lee, Chen-Yong Lin, Ken-ichi Kiyomiya |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Physiology
Blotting Western Proteinase Inhibitory Proteins Secretory Antineoplastic Agents Suramin Cell Line chemistry.chemical_compound Sphingosine Zymogen medicine Humans Matriptase Sphingosine-1-phosphate Mammary Glands Human Serine protease Membrane Glycoproteins biology Serine Endopeptidases Intracellular Signaling Peptides and Proteins Epithelial Cells Cell Biology Molecular biology Transmembrane protein Epithelium Enzyme Activation Protein Transport medicine.anatomical_structure Microscopy Fluorescence chemistry Hepatocyte biology.protein Hepatocyte growth factor Lysophospholipids medicine.drug |
| Zdroj: | American Journal of Physiology-Cell Physiology. 288:C932-C941 |
| ISSN: | 1522-1563 0363-6143 |
| DOI: | 10.1152/ajpcell.00497.2004 |
| Popis: | Activation of single-chain, latent matriptase, a type II transmembrane serine protease, depends on the weak proteolytic activity of its own zymogen as well as its cognate inhibitor, hepatocyte growth factor activator inhibitor 1 (HAI-1). Oligomerization of matriptase zymogens and HAI-1, and probably its interaction with other proteins, has been proposed to occur during matriptase activation. In the present study, we examined the cellular events associated with matriptase activation triggered either by the physiological inducer sphingosine 1-phosphate (S1P) or by a chemical inducer, the polyanionic compound suramin. S1P-induced matriptase translocation to cell-cell contacts, where it is activated, is an F-actin polymerization-dependent process. Conversely, suramin-induced matriptase accumulation and activation at vesicle-like structures is an F-actin polymerization-independent process. While matriptase activation can occur at different subcellular locations, both S1P- and suramin-induced matriptase accumulation form unique subcellular structures, termed activation foci, where oligomerization of matriptase zymogens and HAI-1 may occur, promoting matriptase activation. Furthermore, matriptase activation may be regulated by intracellular signaling, because Ro 31-8220, a bisindolylmaleimide protein kinase C inhibitor, inhibited both S1P- and suramin-induced activation. The requirement of HAI-1 for matriptase activation and the coincidence of HAI-1 and matriptase in activation foci apparently provide rapid access of HAI-1 for the inhibition of matriptase immediately after its activation. Indeed, all activated matriptase was detected in complexes with HAI-1 only 5 min after suramin stimulation. The close temporospatial coupling of matriptase activation with its inhibition suggests that the proteolytic activity of this enzyme must be well controlled and that the proteolysis of matriptase substrates may be tightly regulated by this mechanism. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|