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Updated: Aug 10, 2026

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

Apoptosis-linked gene-2 connects the Raf-1 and ASK1 signalings

Changmin Chen1, Arthur J Sytkowski

  • 1Laboratory for Cell and Molecular Biology, Division of Hematology and Oncology, Beth Israel Deaconess Medical Center, Department of Medicine, Harvard Medical School, USA. cchen3@bidmc.harvard.edu

Biochemical and Biophysical Research Communications
|June 1, 2005
PubMed

Insights

Raf-1, a key regulator of cell survival, may prevent apoptosis by blocking the phosphorylation of apoptosis-linked gene-2 (ALG-2) by apoptosis signal-regulating kinase 1 (ASK1). This identifies a novel anti-apoptotic mechanism for Raf-1.

Area of Science:

  • Cell biology
  • Molecular biology
  • Biochemistry

Background:

  • Raf-1 is crucial for cell proliferation, differentiation, and survival.
  • Raf-1's essential anti-apoptotic function is not fully understood.
  • The specific molecules mediating Raf-1's anti-apoptotic effects remain unidentified.

Purpose of the Study:

  • To identify novel substrates of Raf-1.
  • To elucidate the molecular mechanisms underlying Raf-1's anti-apoptotic function.

Main Methods:

  • Yeast two-hybrid system to identify protein interactions.
  • In vitro kinase assays to assess protein phosphorylation.
  • Investigating the interaction between Raf-1, ALG-2, and ASK1.

Main Results:

  • Raf-1 kinase domain interacts with apoptosis-linked gene-2 (ALG-2).
  • Raf-1 and apoptosis signal-regulating kinase 1 (ASK1) both phosphorylate ALG-2.
  • Raf-1 inhibits ASK1-mediated phosphorylation of ALG-2.

Conclusions:

  • Raf-1 may exert its anti-apoptotic function by preventing ASK1-dependent phosphorylation of ALG-2.
  • This interaction highlights a novel pathway in apoptosis regulation.
  • Further research is warranted to confirm this mechanism in vivo.
Keywords:
NASA Discipline Cell BiologyNon-NASA Center

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