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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

[Regulation mechanism of HCV NS5A on p53 protein transactivity]

Guo-zhong Gong1, Yong-fang Jiang, Ying-hua Zhu

  • 1Liver Disease Research Center, Second Xiangya Hospital, Central South University, Changsha 410011, China.

Zhonghua Gan Zang Bing Za Zhi = Zhonghua Ganzangbing Zazhi = Chinese Journal of Hepatology
|April 12, 2003
PubMed
Abstract

Insights

Hepatitis C virus NS5A protein inhibits p53 transactivity on the p21 promoter. This occurs by reducing p53

Area of Science:

  • Molecular Biology
  • Virology
  • Cancer Research

Background:

  • Hepatitis C virus (HCV) is a significant global health concern.
  • The p53 tumor suppressor protein plays a critical role in cellular responses to stress.
  • Understanding viral protein interactions with host cell machinery is crucial for therapeutic development.

Purpose of the Study:

  • To investigate the inhibitory effect of HCV NS5A on p53 protein transactivity.
  • To elucidate the underlying mechanism of HCV NS5A-mediated inhibition of p53.

Main Methods:

  • Utilized a luciferase reporter gene system to assess p53 transactivity on the p21 promoter.
  • Employed electrophoretic mobility-shift assay (EMSA) to evaluate p53 DNA-binding ability.
  • Investigated dose-dependent effects of HCV NS5A expression.

Main Results:

  • Both endogenous and exogenous p53 proteins significantly activated the p21 promoter.
  • HCV NS5A protein demonstrated a dose-dependent inhibition of p53 transactivity.
  • EMSA revealed that HCV NS5A suppresses the binding affinity of p53 to its specific DNA sequence.

Conclusions:

  • HCV NS5A effectively inhibits p53 protein transactivity on the p21 promoter.
  • The mechanism involves the suppression of p53's DNA-binding ability.
  • These findings contribute to understanding HCV pathogenesis and potential therapeutic targets.

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