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Updated: Jul 17, 2026
09:20
In situ Subcellular Fractionation of Adherent and Non-adherent Mammalian Cells
Published on: July 23, 2010
TopBP1 regulates human papillomavirus type 16 E2 interaction with chromatin
Mary M Donaldson1, Winifred Boner, Iain M Morgan
1Institute of Comparative Medicine, Division of Pathological Sciences, University of Glasgow Faculty of Veterinary Medicine, Bearsden Road, Glasgow, G61 1QH Scotland.
Journal of Virology
|February 9, 2007
Summary
Human papillomavirus type 16 E2 protein
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Human papillomavirus type 16 (HPV16) E2 protein is crucial for viral genome regulation.
- HPV16 E2 interacts with Topoisomerase II-binding protein 1 (TopBP1), a key factor in DNA replication.
Purpose of the Study:
- To investigate the impact of TopBP1 absence on HPV16 E2.
- To explore the role of TopBP1 in HPV16 E2's interaction with chromatin and its function.
Main Methods:
- Analyzing HPV16 E2 protein complex formation in the absence of TopBP1.
- Assessing HPV16 E2's transcriptional activity and chromatin binding.
- Observing the colocalization of HPV16 E2 and TopBP1 during mitosis.
Main Results:
- Absence of TopBP1 causes HPV16 E2 to form alternative complexes with increased chromatin affinity.
- HPV16 E2's transcriptional regulatory functions (activation/repression) remain largely unaffected by TopBP1 absence.
- HPV16 E2 and TopBP1 colocalize on mitotic chromatin, suggesting a role for TopBP1 as a mitotic receptor for HPV16 E2.
Conclusions:
- TopBP1 influences HPV16 E2's cellular localization and chromatin interaction.
- TopBP1 may act as a crucial cellular factor mediating HPV16 E2's association with mitotic chromatin.
- Understanding this interaction is vital for comprehending the HPV16 viral life cycle regulation.
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