JCB logo
Quantitative Colocalization Analysis Software
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents
This Article
Right arrow Full Text
Right arrow Full Text (PDF, 285K)
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 Farschon, D. M.
Right arrow Articles by Newmeyer, D. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Farschon, D. M.
Right arrow Articles by Newmeyer, D. D.
Right arrowPubmed/NCBI databases
*Substance via MeSH
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Facebook   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

© The Rockefeller University Press, 0021-9525/1997//1117 $5.00
The Journal of Cell Biology, Volume 137, Number 5, , 1997 1117-1125

Article

Temporal Phases in Apoptosis Defined by the Actions of Src Homology 2 Domains, Ceramide, Bcl-2, Interleukin-1β Converting Enzyme Family Proteases, and a Dense Membrane Fraction



David M. Farschon*, Clément Couture{ddagger}, Tomas Mustelin{ddagger}, and Donald D. Newmeyer*

* Division of Cellular Immunology, {ddagger} Division of Cell Biology, La Jolla Institute for Allergy and Immunology, San Diego, California 92121

We have begun to explore the mechanisms of apoptosis using a cell-free system based on extracts from Xenopus eggs. Nuclei assembled or placed in these extracts undergo the morphological changes typical of apoptosis and eventually disintegrate. We used this system to investigate the potential involvement in apoptosis of proteins containing Src homology 2 (SH2) domains, which are known to interact with specific tyrosine-phosphorylated ligands. SH2 domains from a number of signaling proteins, including Lck, Src, and Abl, inhibited apoptosis when present at concentrations of 10–100 nM. The inhibition was dependent on specific interaction with endogenous tyrosine-phosphorylated ligands. A synthetic peptide ligand for Src family SH2 domains also inhibited apoptosis in a phosphotyrosine-dependent manner. Kinetic analysis defined three phases in the apoptotic process occurring in this cell-free system. SH2 domains and ceramide act throughout the first 60–90 min of the process (the "initiation" phase). Next, Bcl-2, interleukin-1β converting enzyme family(CPP32-like) proteases, and the heavy membrane fraction act in a period occurring ~90–120 min after the start of incubation (the "sentencing" phase). In the final phase ("execution"), the process of active nuclear destruction ensues.

1. Abbreviations used in this paper: GST, glutathione-S-transferase; HM, heavy membrane; ICE, interleukin-1β converting enzyme; PLC, phospholipase C; PTyr, phosphotyrosine; SH2, Src homology 2.

Please address all correspondence to Donald D. Newmeyer, La Jolla Institute for Allergy and Immunology, 10355 Science Center Drive, San Diego, CA 92121. Tel.: (619) 558-3500. Fax: (619) 558-3525. e-mail: Don_Newmeyer{at}liai.org

C. Couture's present address is the Terry Fox Molecular Oncology Group, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Qc H3T1E2 Canada.


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 Facebook Facebook   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?


This article has been cited by other articles:



  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents