Related Experiment Video

Updated: Aug 23, 2025

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

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Characterization of the RAS/RAF/ERK Signal Cascade as a Novel Regulating Factor in Alpha-Amanitin-Induced

Doeun Kim1, Min Seo Lee2, Eunji Sung3

  • 1Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 41566, Korea.

International Journal of Molecular Sciences
|October 27, 2022
PubMed

Insights

Alpha-amanitin (α-AMA) triggers liver toxicity by inhibiting RNA polymerase II (RNAP II), leading to aberrant splicing and cell death. This study reveals the RAS/RAF/ERK pathway activation as a key mechanism in α-AMA-induced hepatotoxicity.

Area of Science:

  • Hepatology
  • Molecular Biology
  • Toxicology

Background:

  • Alpha-amanitin (α-AMA) is a potent toxin causing liver damage via RNA polymerase II (RNAP II) inhibition.
  • The precise signaling pathways activated by α-AMA in hepatocytes remain incompletely understood.

Purpose of the Study:

  • To elucidate the molecular mechanisms and signaling pathways involved in α-AMA-induced hepatotoxicity.
  • To identify novel cellular targets and pathways affected by α-AMA exposure.

Main Methods:

  • Quantitative phosphoproteomics was employed to analyze protein phosphorylation changes in Huh-7 cells.
  • Molecular biological techniques were used to validate findings.
  • Bioinformatics analysis was performed to assess time-dependent effects of α-AMA.

Main Results:

  • α-AMA exposure activated the RAS/RAF/ERK signaling pathway in a time-dependent manner.
  • Increased phosphorylation was observed in ERK pathway components, U2AF65, and SPF45, key splicing factors.
  • Aberrant splicing events were linked to α-AMA-induced cell death.

Conclusions:

  • α-AMA exposure activates the RAS/RAF/ERK signaling pathway, leading to aberrant splicing.
  • This aberrant splicing, driven by the activated signaling pathway, is a novel mechanism contributing to α-AMA-induced hepatocyte cell death.
Keywords:
RAS/RAF/ERK signaling pathwayacute liver failurealpha-amanitinglobal phosphoproteometoxic mushroom

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