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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

CKII site in Epstein-Barr virus nuclear protein 2 controls binding to hSNF5/Ini1 and is important for growth

Bogaslaw Kwiatkowski1, Szu Yu Jenny Chen, William H Schubach

  • 1VA Puget Sound Health Care System, S-111-ONC, 1660 S. Columbian Way, Seattle, WA 98108, USA.

Journal of Virology
|May 14, 2004
PubMed

Insights

Substitution mutagenesis revealed two interaction sites between EBNA2 and hSNF5/Ini1. A mutation at a CKII phosphorylation site (SS469) is crucial for this interaction and EBNA2

Area of Science:

  • Molecular biology
  • Virology
  • Cellular biology

Background:

  • Epstein-Barr virus nuclear antigen 2 (EBNA2) plays a role in viral replication and cellular transformation.
  • The human Switch/Sucrose Non-Fermental 5 (hSNF5)/Ini1 protein is a component of the SWI/SNF chromatin remodeling complex.
  • Understanding the interaction between EBNA2 and hSNF5/Ini1 is crucial for elucidating EBNA2's oncogenic mechanisms.

Purpose of the Study:

  • To identify the specific sites on EBNA2 involved in its interaction with hSNF5/Ini1.
  • To investigate the role of CKII phosphorylation at site SS469 in mediating this interaction.
  • To assess the impact of mutations affecting EBNA2-hSNF5/Ini1 binding on EBNA2's growth-promoting activity.

Main Methods:

  • Substitution mutagenesis was employed to alter specific amino acid residues within EBNA2.
  • Alanine substitution was used to create a non-phosphorylatable mutant at the SS469 site.
  • Transcomplementation assays were performed to evaluate the functional consequences of EBNA2 mutations.

Main Results:

  • Two distinct interaction sites between EBNA2 and hSNF5/Ini1 were identified: 286IPP and DQQ313.
  • A mutation at the CKII phosphorylation site (SS469) was found to be essential for the EBNA2-hSNF5/Ini1 interaction.
  • An alanine substitution at SS469 (SS469AA) abolished EBNA2 binding to hSNF5/Ini1 and reduced EBNA2's growth-promotion potential.

Conclusions:

  • The interaction between EBNA2 and hSNF5/Ini1 is mediated by specific sites, including 286IPP and DQQ313.
  • CKII phosphorylation at SS469 is critical for the EBNA2-hSNF5/Ini1 interaction and EBNA2's transforming activity.
  • Targeting this interaction could offer insights into Epstein-Barr virus-associated oncogenesis.

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