Cathepsin L is responsible for processing and activation of proheparanase through multiple cleavages of a linker segment Journal Article
| Authors: | Abboud-Jarrous, G.; Atzmon, R.; Peretz, T.; Palermo, C.; Gadea, B. B.; Joyce, J. A.; Vlodavsky, I. |
| Article Title: | Cathepsin L is responsible for processing and activation of proheparanase through multiple cleavages of a linker segment |
| Abstract: | Heparanase is an endo-β-D-glucuronidase that degrades heparan sulfate in the extracellular matrix and on the cell surface. Human proheparanase is produced as a latent protein of 543 amino acids whose activation involves excision of an internal linker segment (Ser110-Gln157), yielding the active heterodimer composed of 8- and 50-kDa subunits. Applying cathepsin L knock-out tissues and cultured fibroblasts, as well as cathepsin L gene silencing and overexpression strategies, we demonstrate, for the first time, that removal of the linker peptide and conversion of proheparanase into its active 8 + 50-kDa form is brought about predominantly by cathepsin L. Excision of a 10-amino acid peptide located at the C terminus of the linker segment between two functional cathepsin L cleavage sites (Y156Q and Y146Q) was critical for activation of proheparanase. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry demonstrates that the entire linker segment is susceptible to multiple endocleavages by cathepsin L, generating small peptides. Mass spectrometry demonstrated further that an active 8-kDa subunit can be generated by several alternative adjacent endocleavages, yielding the precise 8-kDa subunit and/or slightly elongated forms. Altogether, the mode of action presented here demonstrates that processing and activation of proheparanase can be brought about solely by cathepsin L. The critical involvement of cathepsin L in proheparanase processing and activation offers new strategies for inhibiting the prometastatic, proangiogenic, and proinflammatory activities of heparanase. © 2008 by The American Society for Biochemistry and Molecular Biology, Inc. |
| Keywords: | controlled study; human tissue; unclassified drug; human cell; molecular genetics; mass spectrometry; metabolism; gene overexpression; serine; carboxy terminal sequence; small interfering rna; protein binding; rna, small interfering; enzyme activation; cell line, tumor; physiology; extracellular matrix; gene expression regulation; amines; amino acid sequence; molecular sequence data; sequence homology, amino acid; genetic engineering; cell culture; tumor cell line; cell membranes; fibroblast; fibroblasts; binding site; protein structure, tertiary; binding sites; gene silencing; cathepsin; cathepsins; high performance liquid chromatography; amination; amino acids; organic acids; sequence homology; matrix assisted laser desorption ionization time of flight mass spectrometry; enzyme binding; mass spectrometers; protein tertiary structure; protein cross linking; heparan sulfate; amino acid peptides; glycine; fibroblast culture; tissue; enzyme active site; gene expression regulation, enzymologic; cell surface; cell surfaces; overexpression; spectrum analysis; cathepsin l; beta glucuronidase; cleavage sites; desorption; polyacrylates; spectrometers; spectrometry; c terminuses; extracellular matrixes; glucuronidase; heparan sulfates; heparanase; human proheparanase; knock outs; laser desorption ionization times; linker peptides; mode of actions; new strategies; proinflammatory; proheparanase; cysteine proteinase; cysteine endopeptidases |
| Journal Title: | Journal of Biological Chemistry |
| Volume: | 283 |
| Issue: | 26 |
| ISSN: | 0021-9258 |
| Publisher: | American Society for Biochemistry and Molecular Biology |
| Date Published: | 2008-06-27 |
| Start Page: | 18167 |
| End Page: | 18176 |
| Language: | English |
| DOI: | 10.1074/jbc.M801327200 |
| PUBMED: | 18450756 |
| PROVIDER: | scopus |
| PMCID: | PMC2440611 |
| DOI/URL: | |
| Notes: | --- - "Cited By (since 1996): 27" - "Export Date: 17 November 2011" - "CODEN: JBCHA" - "Source: Scopus" |
Altmetric
Citation Impact
BMJ Impact Analytics
Related MSK Work