JCB logo
HYBRIGENICS
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents
This Article
Right arrow Full Text
Right arrow PDF (Full Text)
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 Lavoie, C.
Right arrow Articles by Bergeron, J.J.M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Lavoie, C.
Right arrow Articles by Bergeron, J.J.M.
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?
J. Cell Biol., Volume 146, Number 2, July 26, 1999 285-300
Copyright © 1999 by The Rockefeller University Press.

Roles for {alpha}2p24 and COPI in Endoplasmic Reticulum Cargo Exit Site Formation

C. Lavoiea, J. Paiementa, M. Dominguezb, L. Roya, S. Dahanb, J.N. Gushueb, and J.J.M. Bergeronb
a Département de Pathologie et Biologie Cellulaire, Faculté de Médecine, Université de Montréal, Québec, Canada H3C 3J7
b Department of Anatomy and Cell Biology, McGill University, Québec, Canada H3A 2B2

Correspondence to: J. Paiement, Département de Pathologie et Biologie Cellulaire, Faculté de Médecine, Université de Montréal, C.P. 6128, Succursale Centre-ville, Montréal, Québec, Canada, H3C 3J7., paiemej{at}patho.umontreal.ca (E-mail), (514) 343-7259 (phone), (514) 343-2459 (fax)

A two-step reconstitution system for the generation of ER cargo exit sites from starting ER-derived low density microsomes (LDMs; 1.17 g/cc) is described. The first step is mediated by the hydrolysis of Mg2+ATP and Mg2+GTP, leading to the formation of a transitional ER (tER) with the soluble cargo albumin, transferrin, and the ER-to-Golgi recycling membrane proteins {alpha}2p24 and p58 (ERGIC-53, ER-Golgi intermediate compartment protein) enriched therein. Upon further incubation (step two) with cytosol and mixed nucleotides, interconnecting smooth ER tubules within tER transforms into vesicular tubular clusters (VTCs). The cytosolic domain of {alpha}2p24 and cytosolic COPI coatomer affect VTC formation. This is deduced from the effect of antibodies to the COOH-terminal tail of {alpha}2p24, but not of antibodies to the COOH-terminal tail of calnexin on this reconstitution, as well as the demonstrated recruitment of COPI coatomer to VTCs, its augmentation by GTP{gamma}S, inhibition by Brefeldin A (BFA), or depletion of ß-COP from cytosol. Therefore, the p24 family member, {alpha}2p24, and its cytosolic coat ligand, COPI coatomer, play a role in the de novo formation of VTCs and the generation of ER cargo exit sites.

Key Words: cell-free assembly, transitional endoplasmic reticulum, endoplasmic reticulum cargo exit sites, {alpha}2p24, COPI


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