Related Experiment Video

Updated: Nov 2, 2025

Fully Processed Recombinant KRAS4b: Isolating and Characterizing the Farnesylated and Methylated Protein
07:08

Fully Processed Recombinant KRAS4b: Isolating and Characterizing the Farnesylated and Methylated Protein

Published on: January 16, 2020

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Inhibition of K-Ras4B-plasma membrane association with a membrane microdomain-targeting peptide

Fang-Yi Li1, Zhen-Feng Zhang2, Stephanie Voss3,4

  • 1Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University Beijing 100084 China chen-yx@mail.tsinghua.edu.cn.

Chemical Science
|June 14, 2021
PubMed

Insights

A novel peptide inhibitor, Memrasin, effectively detaches K-Ras4B protein from the plasma membrane, inhibiting cancer cell viability. This direct inhibition of K-Ras4B-PM interaction offers a promising anti-Ras therapeutic strategy.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Oncology

Background:

  • K-Ras4B protein association with the plasma membrane (PM) is crucial for its signaling.
  • Targeting K-Ras4B-PM interactions presents a potential anti-Ras therapeutic avenue.
  • Modulating protein-PM interactions remains a significant challenge.

Purpose of the Study:

  • To develop a potent and isoform-selective peptide inhibitor targeting K-Ras4B-PM interaction.
  • To investigate the efficacy of this inhibitor in disrupting K-Ras4B signaling and reducing cancer cell viability.

Main Methods:

  • Development of Memrasin, a peptide inhibitor incorporating a K-Ras4B C-terminal binding sequence and an endosome-escape motif.
  • Analysis of Memrasin's ability to form peptide-enriched domains in membrane lipid raft (l d) regions.
  • Assessment of Memrasin's impact on K-Ras4B tethering to the PM, Ras signaling, and human lung cancer cell viability.

Main Results:

  • Memrasin successfully abrogates K-Ras4B tethering to the plasma membrane.
  • The inhibitor impairs Ras signaling activity.
  • Memrasin demonstrates dose-responsive and K-Ras-dependent reduction in human lung cancer cell viability.

Conclusions:

  • Memrasin is a first-in-class direct inhibitor of K-Ras4B-PM interaction.
  • It serves as a valuable tool for studying K-Ras4B's biological functions.
  • Memrasin represents a potential starting point for developing novel anti-Ras therapeutics.

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