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

J. Biol. Chem., Vol. 280, Issue 9, 7867-7874, March 4, 2005

This Article Full Text Full Text (PDF) All Versions of this Article: 280/9/7867    most recent M413553200v1 Alert me when this article is cited 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 Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kragt, A. Articles by Distel, B. Search for Related Content PubMed PubMed Citation Articles by Kragt, A. Articles by Distel, B. Social Bookmarking                      What's this?

The Saccharomyces cerevisiae Peroxisomal Import Receptor Pex5p Is Monoubiquitinated in Wild Type Cells^*

Astrid Kragt, Tineke Voorn-Brouwer, Marlene van den Berg, and Ben Distel

From the Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands

Pex5p is a mobile receptor for peroxisomal targeting signal type I-containing proteins that cycles between the cytoplasm and the peroxisome. Here we show that Pex5p is a stable protein that is monoubiquitinated in wild type cells. By making use of mutants defective in vacuolar or proteasomal degradation we demonstrate that monoubiquitinated Pex5p is not a breakdown intermediate of either system. Monoubiquitinated Pex5p is localized to peroxisomes, and ubiquitination requires the presence of functional docking and RING finger complexes, which suggests that it is a late event in peroxisomal matrix protein import. In pex1, pex4, pex6, pex15, and pex22 mutants, all of which are blocked in the terminal steps of peroxisomal matrix protein import, polyubiquitinated forms of Pex5p accumulate, ubiquitination being dependent on the ubiquitin-conjugating enzyme Ubc4p. However, Ubc4p is not required for Pex5p ubiquitination in wild type cells, and cells lacking Ubc4p are not affected in peroxisome biogenesis. These results indicate that Pex5p monoubiquitination in wild type cells serves to regulate rather than to degrade Pex5p, which is supported by the observed stability of Pex5p. We propose that Pex5p monoubiquitination in wild type cells is required for the recycling of Pex5p from the peroxisome, whereas Ubc4p-mediated polyubiquitination of Pex5p in mutants blocked in the terminal steps of peroxisomal matrix protein import may function as a disposal mechanism for Pex5p when it gets stuck in the import pathway.

Received for publication, December 2, 2004 , and in revised form, December 28, 2004.

^* This work was supported by the Netherlands Organization of Scientific Research and European Community Grant QLG2-CT-2001-01663. 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.

These authors contributed equally to this work.

To whom correspondence should be addressed: Dept. of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands. Tel.: 31-20-5665127; Fax: 31-20-6915519; E-mail: b.distel{at}amc.uva.nl.

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

This article has been cited by other articles:

				C. P. Grou, A. F. Carvalho, M. P. Pinto, S. Wiese, H. Piechura, H. E. Meyer, B. Warscheid, C. Sa-Miranda, and J. E. Azevedo Members of the E2D (UbcH5) Family Mediate the Ubiquitination of the Conserved Cysteine of Pex5p, the Peroxisomal Import Receptor J. Biol. Chem., May 23, 2008; 283(21): 14190 - 14197. [Abstract] [Full Text] [PDF]

				A. F. Carvalho, M. P. Pinto, C. P. Grou, I. S. Alencastre, M. Fransen, C. Sa-Miranda, and J. E. Azevedo Ubiquitination of Mammalian Pex5p, the Peroxisomal Import Receptor J. Biol. Chem., October 26, 2007; 282(43): 31267 - 31272. [Abstract] [Full Text] [PDF]

				C. Williams, M. van den Berg, R. R. Sprenger, and B. Distel A Conserved Cysteine Is Essential for Pex4p-dependent Ubiquitination of the Peroxisomal Import Receptor Pex5p J. Biol. Chem., August 3, 2007; 282(31): 22534 - 22543. [Abstract] [Full Text] [PDF]

				H. W. Platta, F. E. Magraoui, D. Schlee, S. Grunau, W. Girzalsky, and R. Erdmann Ubiquitination of the peroxisomal import receptor Pex5p is required for its recycling J. Cell Biol., April 23, 2007; 177(2): 197 - 204. [Abstract] [Full Text] [PDF]

				S. Leon and S. Subramani A Conserved Cysteine Residue of Pichia pastoris Pex20p Is Essential for Its Recycling from the Peroxisome to the Cytosol J. Biol. Chem., March 9, 2007; 282(10): 7424 - 7430. [Abstract] [Full Text] [PDF]

				A. Schluter, S. Fourcade, R. Ripp, J. L. Mandel, O. Poch, and A. Pujol The Evolutionary Origin of Peroxisomes: An ER-Peroxisome Connection Mol. Biol. Evol., April 1, 2006; 23(4): 838 - 845. [Abstract] [Full Text] [PDF]

				A. van der Zand, I. Braakman, H. J. Geuze, and H. F. Tabak The return of the peroxisome. J. Cell Sci., March 15, 2006; 119(Pt 6): 989 - 994. [Abstract] [Full Text] [PDF]

				S. Leon, L. Zhang, W. H. McDonald, J. Yates III, J. M. Cregg, and S. Subramani Dynamics of the peroxisomal import cycle of PpPex20p: ubiquitin-dependent localization and regulation J. Cell Biol., January 3, 2006; 172(1): 67 - 78. [Abstract] [Full Text] [PDF]

				B. K. Zolman, M. Monroe-Augustus, I. D. Silva, and B. Bartel Identification and Functional Characterization of Arabidopsis PEROXIN4 and the Interacting Protein PEROXIN22 PLANT CELL, December 1, 2005; 17(12): 3422 - 3435. [Abstract] [Full Text] [PDF]