JCB logo
Cytokines in immune regulation
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents
Published 19 December 2005. doi:10.1083/jcb.200510018
The Rockefeller University Press, 0021-9525 $8.00
JCB, Volume 171, Number 6, 981-990
This Article
Right arrow Full Text
Right arrow PDF (Full Text)
Right arrow PPT slides of all figures
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 JCB
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 Reese, C.
Right arrow Articles by Mayer, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Reese, C.
Right arrow Articles by Mayer, A.
Right arrowPubmed/NCBI databases
*Compound via MeSH
*Substance via MeSH
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

 Transition from hemifusion to pore opening is rate limiting for vacuole membrane fusion

Christoph Reese and Andreas Mayer

Département de Biochimie, Université de Lausanne, 1066 Epalinges, Switzerland

Correspondence to Andreas Mayer: Andreas.Mayer{at}unil.ch

Fusion pore opening and expansion are considered the most energy-demanding steps in viral fusion. Whether this also applies to soluble N-ethyl-maleimide sensitive fusion protein attachment protein receptor (SNARE)– and Rab-dependent fusion events has been unknown. We have addressed the problem by characterizing the effects of lysophosphatidylcholine (LPC) and other late-stage inhibitors on lipid mixing and pore opening during vacuole fusion. LPC inhibits fusion by inducing positive curvature in the bilayer and changing its biophysical properties. The LPC block reversibly prevented formation of the hemifusion intermediate that allows lipid, but not content, mixing. Transition from hemifusion to pore opening was sensitive to guanosine-5'-({gamma}-thio)triphosphate. It required the vacuolar adenosine triphosphatase V0 sector and coincided with its transformation. Pore opening was rate limiting for the reaction. As with viral fusion, opening the fusion pore may be the most energy-demanding step for intracellular, SNARE-dependent fusion reactions, suggesting that fundamental aspects of lipid mixing and pore opening are related for both systems.

Abbreviations used in this paper: ALP, alkaline phosphatase; BAPTA, 1,2-bis-(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid; GTP{gamma}S, guanosine-5'-({gamma}-thio)triphosphate; LPC, lysophosphatidylcholine; MED, myristoylated alanine-rich C kinase substrate effector domain peptide; Rh-PE, lissamine rhodamine B 1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine.


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