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Updated: Jul 16, 2026

Yeast As a Chassis for Developing Functional Assays to Study Human P53
14:57

Yeast As a Chassis for Developing Functional Assays to Study Human P53

Published on: August 4, 2019

Ribosomal protein S7 as a novel modulator of p53-MDM2 interaction: binding to MDM2, stabilization of p53 protein, and

D Chen1, Z Zhang, M Li

  • 1Department of Pharmacology and Toxicology, Division of Clinical Pharmacology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.

Oncogene
|February 22, 2007
PubMed

Insights

Ribosomal protein S7 binds to MDM2, stabilizing the tumor suppressor p53 by preventing its degradation. This interaction enhances p53 activity, inhibiting cancer cell growth and offering new therapeutic avenues.

Area of Science:

  • Molecular Biology
  • Oncology
  • Biochemistry

Background:

  • MDM2 (mouse double minute 2) is a key negative regulator of the tumor suppressor p53.
  • MDM2 promotes p53 degradation, impacting carcinogenesis and tumor progression.
  • Understanding MDM2-p53 interaction regulation is crucial for cancer therapy.

Purpose of the Study:

  • To identify novel MDM2-binding proteins.
  • To investigate the functional consequences of the interaction between MDM2 and novel binding partners.
  • To explore potential therapeutic strategies targeting the MDM2-p53 pathway.

Main Methods:

  • Yeast two-hybrid screening of a human prostate cDNA library using full-length MDM2 as bait.
  • In vitro and in vivo binding assays to confirm protein interactions.
  • Analysis of p53 protein levels, ubiquitination, transactivational activity, apoptosis, and cell proliferation upon S7 overexpression.

Main Results:

  • Ribosomal protein S7 (S7) was identified as a novel MDM2-interacting protein.
  • S7 forms a ternary complex with MDM2 and p53, modulating their interaction.
  • S7 binding abrogates MDM2-mediated p53 ubiquitination, stabilizing p53 and enhancing its tumor-suppressive functions.
  • Overexpression of S7 increases p53 activity, induces apoptosis, and inhibits cell proliferation.

Conclusions:

  • S7 is a novel binding partner of MDM2, contributing to the regulation of p53 stability.
  • The MDM2-S7 interaction offers a new target for cancer prevention and therapy by modulating the p53 pathway.
  • Further research into S7's role could lead to novel therapeutic strategies for various cancers.

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