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Isolation and Quantification of Epstein-Barr Virus from the P3HR1 Cell Line
09:14

Isolation and Quantification of Epstein-Barr Virus from the P3HR1 Cell Line

Published on: September 28, 2022

SCFSkp2 complex targeted by Epstein-Barr virus essential nuclear antigen

Jason S Knight1, Nikhil Sharma, Erle S Robertson

  • 1Department of Microbiology and Abramson Comprehensive Cancer Center, University of Pennsylvania Medical School, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, USA.

Molecular and Cellular Biology
|February 17, 2005
PubMed

Insights

Epstein-Barr virus nuclear antigen 3C (EBNA3C) hijacks the SCFSkp2 complex to degrade the cell cycle inhibitor p27. This viral usurpation of the ubiquitin-proteasome system offers a new mechanism for EBV-driven cancer development.

Area of Science:

  • Molecular Biology
  • Virology
  • Cancer Biology

Background:

  • Cell cycle protein stability is regulated by the ubiquitin-proteasome system.
  • The E3 ubiquitin ligase SCFSkp2 targets key cell cycle proteins like p27, E2F, and c-myc for degradation.
  • Dysregulation of SCFSkp2 is implicated in human cancers.

Purpose of the Study:

  • To investigate the role of Epstein-Barr virus (EBV) nuclear antigen 3C (EBNA3C) in cell cycle regulation.
  • To elucidate the mechanism by which EBV influences the SCFSkp2 complex and its targets.

Main Methods:

  • Investigated the association of EBNA3C with cyclin A/cdk2 complexes.
  • Assessed the impact of EBNA3C on the stability of the kinase inhibitor p27.
  • Examined the recruitment of SCFSkp2 activity to cyclin A complexes by EBNA3C.

Main Results:

  • EBNA3C binds to cyclin A/cdk2 complexes, disrupting p27 and increasing kinase activity.
  • EBNA3C facilitates the recruitment of SCFSkp2 to cyclin A complexes.
  • This interaction leads to the ubiquitination and degradation of p27.

Conclusions:

  • EBNA3C usurps the SCFSkp2 ubiquitin ligase machinery to control p27 stability.
  • This represents a novel mechanism for EBV to regulate cell cycle progression.
  • Understanding this interaction provides insights into EBV-associated oncogenesis.

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