HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 283, Issue 26, 18167-18176, June 27, 2008

This Article Full Text Full Text (PDF) All Versions of this Article: 283/26/18167    most recent M801327200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Abboud-Jarrous, G. Articles by Vlodavsky, I. Search for Related Content PubMed PubMed Citation Articles by Abboud-Jarrous, G. Articles by Vlodavsky, I. Social Bookmarking                      What's this?

Cathepsin L Is Responsible for Processing and Activation of Proheparanase through Multiple Cleavages of a Linker Segment^*

Ghada Abboud-Jarrous, Ruth Atzmon, Tamar Peretz, Carmela Palermo, Bedrick B. Gadea, Johanna A. Joyce, and Israel Vlodavsky^¶1

From the Department of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem 91120, Israel, the Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York 10021, and the ^¶Cancer and Vascular Biology Research Center, The Bruce Rappaport Faculty of Medicine, Technion, Haifa 31096, Israel

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.

Received for publication, February 19, 2008 , and in revised form, April 29, 2008.

^* This work was supported, in whole or in part, by National Institutes of Health Grants RO1-CA106456 (to I. V.) and R01-CA125162-01 (to J. A. J.) from NCI. This work was also supported by Israel Science Foundation Grant 549/06, the Israel Cancer Research Fund, the Rappaport Family Institute Fund, the Cooperation Program in Cancer Research of the Deutsches Krebsforschungszentrum (DKFZ), and Israel's Ministry of Science and Technology (MOST). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ To whom correspondence should be addressed. Tel.: 972-4-8295410; Fax: 972-4-8523947; E-mail: vlodavsk{at}cc.huji.ac.il.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				L. Fux, N. Feibish, V. Cohen-Kaplan, S. Gingis-Velitski, S. Feld, C. Geffen, I. Vlodavsky, and N. Ilan Structure-Function Approach Identifies a COOH-Terminal Domain That Mediates Heparanase Signaling Cancer Res., March 1, 2009; 69(5): 1758 - 1767. [Abstract] [Full Text] [PDF]