Related Experiment Video

Updated: Aug 24, 2026

Characterize Disease-related Mutants of RAF Family Kinases by Using a Set of Practical and Feasible Methods
07:49

Characterize Disease-related Mutants of RAF Family Kinases by Using a Set of Practical and Feasible Methods

Published on: July 17, 2019

Binding activity of H-Ras is necessary for in vivo inhibition of ASK1 activity

Jun Du1, Shao Hui Cai, Zhe Shi

  • 1Department of Medical Technology, Nagoya University School of Health Sciences, Aichi 461-8673, Japan. togun@met.nagoya-u.ac.jp

Cell Research
|April 30, 2004
PubMed

Insights

Human Ras (H-Ras) protein interacts with apoptosis signal-regulating kinase 1 (ASK1), inhibiting cell death signaling. This finding reveals a new H-Ras survival mechanism beyond known pathways.

Area of Science:

  • Cellular signaling pathways
  • Apoptosis regulation
  • Oncogene research

Background:

  • H-Ras is a key component of the Ras/Raf/MEK/ERK cascade, crucial for cell survival.
  • Apoptosis signal-regulating kinase 1 (ASK1) mediates cell death in response to various signals.

Purpose of the Study:

  • To investigate the interaction between H-Ras and ASK1.
  • To elucidate the role of H-Ras in regulating ASK1 activity and apoptosis.

Main Methods:

  • In vivo interaction studies between H-Ras and ASK1.
  • Assessment of ASK1 activity and apoptosis induction.
  • Use of Raf antagonist (RafS621A), MEK inhibitor (PD98059), and PI3K inhibitor (LY294002).
  • Immunoprecipitation and kinase assays to confirm binding and activity dependence.

Main Results:

  • H-Ras directly interacts with ASK1, inhibiting its activity and ASK1-induced apoptosis in vivo.
  • Partial reversal of inhibition by RafS621A, with no effect from PD98059 or LY294002.
  • H-Ras/ASK1 interaction and ASK1 inhibition are dependent on H-Ras binding activity.

Conclusions:

  • H-Ras employs a novel mechanism to promote cell survival by inhibiting ASK1.
  • This pathway is independent of the canonical MEK/ERK and PI3K/Akt survival pathways.
  • Suggests a new target for therapeutic intervention in H-Ras-related diseases.

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