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Updated: Jul 20, 2026
06:07
Continuous Fluorescence-Based Endonuclease-Coupled DNA Methylation Assay to Screen for DNA Methyltransferase Inhibitors
Published on: August 5, 2022
Viral oncoproteins target the DNA methyltransferases
W A Burgers1, L Blanchon, S Pradhan
1Wellcome Trust/CRUK Gurdon Institute, University of Cambridge, Cambridge, UK.
Oncogene
|September 20, 2006
Summary
Viral oncoproteins like adenovirus E1A and HPV E7 bind to DNA methyltransferase Dnmt1, regulating its activity. This interaction may help viruses control cell proliferation and drive cells into S phase.
Area of Science:
- Virology
- Molecular Biology
- Epigenetics
Background:
- Small DNA tumor viruses induce cell cycle progression.
- Viral oncoproteins like adenovirus E1A and HPV E7 override proliferation arrest.
- DNA methyltransferase Dnmt1 maintains CpG methylation patterns; disrupted patterns are hallmarks of cancer.
Purpose of the Study:
- To investigate the interaction between viral oncoproteins and Dnmt1.
- To determine if viral oncoproteins regulate Dnmt1 activity.
- To elucidate the mechanism by which viruses manipulate cellular proliferation.
Main Methods:
- In vitro and in vivo association studies.
- Purification of DNA methyltransferase activity.
- Site-directed mutagenesis of viral oncoproteins.
- In vitro enzymatic activity assays.
Main Results:
- Adenovirus 5 E1A and HPV-16 E7 associate with Dnmt1.
- E1A and E7 purify Dnmt1 activity and directly bind Dnmt1.
- A critical E1A mutant (L20) loses Dnmt1 binding and regulatory capacity.
- E1A and E7 stimulate Dnmt1 methyltransferase activity in vitro.
Conclusions:
- Viral oncoproteins directly bind and regulate the enzymatic activity of Dnmt1.
- This interaction provides a novel mechanism for small DNA tumor viruses to control host cell cycle progression.
- The findings suggest a link between viral oncogenesis and epigenetic regulation via Dnmt1.
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