The Journal of Experimental Medicine
MBL International Tel: 800.200.5459 CLICK HERE
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents

Published online 11 July 2005 doi:10.1084/jem.20041685
Rockefeller University Press, 0022-1007 $8.00
JEM, Volume 202, Number 2, 249-259
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow PPT slides of all figures
Right arrow Supplemental Material Index
Right arrow Alert me when this article is cited
Right arrow Citation Map
Services
Right arrow Email this article
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new content in the JEM
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Miyaji, M.
Right arrow Articles by Umehara, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Miyaji, M.
Right arrow Articles by Umehara, H.
Social Bookmarking
 Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?

ARTICLE

Role of membrane sphingomyelin and ceramide in platform formation for Fas-mediated apoptosis

Michihiko Miyaji1,2, Zhe-Xiong Jin1,3, Shohei Yamaoka4, Ryuichi Amakawa2, Shirou Fukuhara2, Satoshi B. Sato5,6, Toshihide Kobayashi5, Naochika Domae7, Tsuneyo Mimori1, Eda T. Bloom8, Toshiro Okazaki4, and Hisanori Umehara1,3

1 Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8507, Japan
2 First Department of Internal Medicine, Kansai Medical University, Moriguchi, Osaka 570-8506, Japan
3 Division of Hematology and Immunology, Department of Internal Medicine, Kanazawa Medical University, Ishikawa 920-0293, Japan
4 Department of Clinical Laboratory Medicine/Hematology, Faculty of Medicine, Tottori University, Yonago, Tottori 683-8504, Japan
5 RIKEN, Wako, Saitama 351-0198, Japan
6 Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
7 Department of Medicine, Osaka Dental University, Hirakata, Osaka 573-1121, Japan
8 Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892

CORRESPONDENCE Hisanori Umehara: umehara{at}kanazawa-med.ac.jp

Engagement of the Fas receptor (CD95) initiates multiple signaling pathways that lead to apoptosis, such as the formation of death-inducing signaling complex (DISC), activation of caspase cascades, and the generation of the lipid messenger, ceramide. Sphingomyelin (SM) is a major component of lipid rafts, which are specialized structures that enhance the efficiency of membrane receptor signaling and are a main source of ceramide. However, the functions of SM in Fas-mediated apoptosis have yet to be clearly defined, as the responsible genes have not been identified. After cloning a gene responsible for SM synthesis, SMS1, we established SM synthase–defective WR19L cells transfected with the human Fas gene (WR/Fas-SM()), and cells that have been functionally restored by transfection with SMS1 (WR/Fas-SMS1). We show that expression of membrane SM enhances Fas-mediated apoptosis through increasing DISC formation, activation of caspases, efficient translocation of Fas into lipid rafts, and subsequent Fas clustering. Furthermore, WR/Fas-SMS1 cells, but not WR/Fas-SM() cells, showed a considerable increase in ceramide generation within lipid rafts upon Fas stimulation. These data suggest that a membrane SM is important for Fas clustering through aggregation of lipid rafts, leading to Fas-mediated apoptosis.


Abbreviations used: aSMase; acid sphingomyelinase, CTx; choleratoxin B; {Delta}{Psi}m, mitochondrial membrane potential; DISC, death-inducing signaling complex; FADD, Fas-associated death domain; FasL, Fas ligand; MBP, maltose-binding protein; PI, propidium iodide; SM; sphingomyelin.


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


This article has been cited by other articles:



  Home | Help | Feedback | Subscriptions | Archive | Search
TABLE OF CONTENTS