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Published on: July 23, 2010
The human papillomavirus 16 E2 protein is stabilised in S phase
Cecilia Johansson1, Sheila V Graham, Edward S Dornan
1Institute of Comparative Medicine, University of Glasgow Faculty of Veterinary Medicine, Glasgow, G61 1QH, UK.
Virology
|September 29, 2009
Summary
Human papillomavirus 16 E2 protein stability and phosphorylation increase during the S phase, optimizing viral DNA replication. Identifying kinases regulating E2 offers therapeutic targets for HPV infections.
Area of Science:
- Virology
- Molecular Biology
- Cell Cycle Regulation
Background:
- The human papillomavirus 16 E2 protein is crucial for viral genome transcription, replication, and segregation.
- E2 interacts with the viral origin of replication and recruits the viral helicase E1 to initiate DNA replication.
Purpose of the Study:
- To investigate the cell cycle regulation of HPV16 E2 protein.
- To identify host cell factors and mechanisms controlling E2 stability and phosphorylation for viral replication.
Main Methods:
- Cell cycle synchronization and analysis.
- Western blotting to assess protein levels and phosphorylation.
- Kinase assays to identify E2-interacting kinases.
Main Results:
- HPV16 E2 protein exhibits increased stability and phosphorylation during the S phase of the cell cycle.
- Preliminary data suggests Cyclin-dependent kinase 2 (Cdk2) phosphorylates E2.
- This S phase-specific modification is linked to enhanced viral DNA replication.
Conclusions:
- E2 stabilization and phosphorylation in S phase are critical for efficient HPV replication.
- Cdk2 is a potential kinase responsible for E2 phosphorylation in vivo.
- Targeting E2-regulating enzymes like Cdk2 could offer novel therapeutic strategies against HPV.
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