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Published on: May 5, 2020
EBNA-LP associates with cellular proteins including DNA-PK and HA95
1Channing Laboratory, Harvard Medical School, Boston, Massachusetts 02445, USA.
Journal of Virology
|February 13, 2001
Summary
Epstein-Barr virus nuclear antigen leader protein (EBNA-LP) interacts with DNA-PKcs, HA95, Hsp70, and tubulin proteins. DNA-PKcs phosphorylates EBNA-LP, a process inhibited by Wortmannin.
Area of Science:
- Molecular Biology
- Virology
- Cellular Biology
Background:
- Epstein-Barr virus nuclear antigen leader protein (EBNA-LP) is a key viral protein involved in lymphoblast transformation.
- Understanding EBNA-LP's interactions is crucial for elucidating its role in viral pathogenesis and cellular processes.
Purpose of the Study:
- To identify proteins associated with EBNA-LP.
- To characterize the interaction between EBNA-LP and DNA-PKcs.
- To investigate the functional consequences of this interaction.
Main Methods:
- Immunoprecipitation of Flag-tagged EBNA-LP (FLP) from stably expressing lymphoblasts.
- Protein sequencing to identify associated proteins.
- Immunoblotting to quantify protein association.
- In vitro kinase assays to assess DNA-PKcs activity.
Main Results:
- Identified associations between EBNA-LP and DNA-PKcs, HA95, Hsp70, Hsp27, alpha-tubulin, and beta-tubulin.
- Quantified varying degrees of association, with HA95 showing high affinity.
- Demonstrated that EBNA-LP binds to specific domains of DNA-PKcs.
- Showed that DNA-PKcs phosphorylates EBNA-LP in vitro, and this is inhibited by Wortmannin.
Conclusions:
- EBNA-LP interacts with a complex of cellular proteins, including DNA-PKcs.
- DNA-PKcs phosphorylates EBNA-LP, suggesting a role in regulating EBNA-LP function.
- These findings provide new insights into the molecular mechanisms of EBNA-LP in host cell manipulation.
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