Skip Navigation


Journal of Biochemistry Advance Access originally published online on February 14, 2008
Journal of Biochemistry 2008 143(5):649-660; doi:10.1093/jb/mvn020
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
143/5/649    most recent
mvn020v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Request Permissions
Google Scholar
Right arrow Articles by Omi, S.
Right arrow Articles by Taniguchi, H.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Omi, S.
Right arrow Articles by Taniguchi, H.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 2008 The Japanese Biochemical Society.

Contribution of Peroxisome-specific Isoform of Lon Protease in Sorting PTS1 Proteins to Peroxisomes

Sizue Omi, Rie Nakata, Kazuko Okamura-Ikeda, Hiroaki Konishi* and Hisaaki Taniguchi

Institute for Enzyme Research, The University of Tokushima, Tokushima 770-8503, Japan

*To whom correspondence should be addressed. Tel: +81 88 633 7427, Fax: +81 88 633 7428, E-mail: konishi{at}ier.tokushima-u.ac.jp

Received January 15, 2008; Accepted January 31, 2008


  Abstract

Using an organelle proteomics approach, we previously studied the rat peroxisome in order to characterize the proteins participating in its biogenesis. A peroxisome-specific isoform of Lon (pLon) protein was accordingly identified. However, the precise role of pLon in peroxisomes remains to be elucidated. Here, we demonstrate that pLon plays a role in processing and activating a specific regulatory protein belonging to the peroxisome targeting signal (PTS) 1-containing proteins. Proteomic analysis of proteins co-immunoprecipitated with Lon suggested that Lon interacts with PMP70 and several enzymes involved in β-oxidation, including acyl-CoA oxidase (AOX). The processing of AOX for its activation in peroxisomes was strongly inhibited in cells expressing a dominant negative form of pLon. Furthermore, a catalase possessing a modified PTS1 sequence was misdistributed in this cell line. pLon exhibits little, if any, in vitro AOX processing activity, and does not process PTS2-containing 3-ketoacyl-coenzyme A thiolase (PTL). Therefore, pLon may specifically control, sort and process PTS1 proteins. Based on the relationship between pLon and the β-oxidation enzymes that regulate peroxisomal morphology, the observation of enlarged peroxisomes in cells expressing recombinant pLon suggests that pLon is a critical factor determining peroxisome morphology.

Key Words: peroxisome, β-oxidation, PTS1, protease, proteomics

Abbreviations: CBB, Coomassie brilliant blue; HEK, human embryonic kidney; RT–PCR, reverse transcriptase–PCR; siRNA, small interference RNA


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.