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Updated: Aug 20, 2026

Detection of Mitochondria Membrane Potential to Study CLIC4 Knockdown-induced HN4 Cell Apoptosis In Vitro
13:20

Detection of Mitochondria Membrane Potential to Study CLIC4 Knockdown-induced HN4 Cell Apoptosis In Vitro

Published on: July 17, 2018

Trichomislin, a novel ribosome-inactivating protein, induces apoptosis that involves mitochondria and caspase-3

Shuang-Li Mi1, Cheng-Cai An, Ye Wang

  • 1The National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, China.

Archives of Biochemistry and Biophysics
|January 11, 2005
PubMed

Insights

A novel protein, trichomislin, from Trichosanthes kirilowii, inhibits protein synthesis and induces apoptosis in choriocarcinoma cells by activating caspases.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Cancer Research

Background:

  • Ribosome-inactivating proteins (RIPs) are a class of proteins with cytotoxic properties.
  • Trichosanthes kirilowii Maxim. is a plant known for its medicinal properties.

Purpose of the Study:

  • To clone, express, and characterize a novel RIP, trichomislin, from Trichosanthes kirilowii.
  • To investigate the mechanism of action and antitumor effects of trichomislin.

Main Methods:

  • Gene cloning and prokaryotic expression of trichomislin.
  • Protein purification using cation-exchange chromatography.
  • Circular-dichroism analysis for secondary structure determination.
  • In vitro protein synthesis inhibition assays.
  • Antitumor activity assessment in choriocarcinoma cell lines.
  • Caspase-3 activity and cytochrome c release assays.

Main Results:

  • Trichomislin was successfully cloned, expressed, and purified.
  • Circular-dichroism analysis revealed the secondary structure composition.
  • Trichomislin inhibited protein synthesis by inactivating ribosomes as an rRNA N-glycosidase.
  • Trichomislin induced apoptosis and inhibited choriocarcinoma cell growth.
  • Trichomislin triggered apoptosis via the mitochondrial pathway, involving caspase-3 activation and cytochrome c release.

Conclusions:

  • Trichomislin is a novel ribosome-inactivating protein with potent antitumor activity.
  • The antitumor mechanism involves inducing apoptosis through the mitochondrial pathway.
  • Trichomislin holds potential as a therapeutic agent for choriocarcinoma.

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