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Updated: Jul 11, 2026
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Analysis of Group IV Viral SSHHPS Using In Vitro and In Silico Methods
Published on: December 21, 2019
Functionally distinct monomers and trimers produced by a viral oncoprotein.
S-H Chung1, R S Weiss, K K Frese
1Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA.
Oncogene
|September 11, 2007
Summary
Adenovirus E4-ORF1 oncoprotein monomers and trimers bind different proteins, leading to distinct cellular functions. This oligomerization-dependent mechanism offers a novel strategy for protein regulation in tumorigenesis.
Area of Science:
- Molecular biology
- Virology
- Cellular biology
Background:
- Protein oligomerization is a key mechanism for regulating protein activity.
- Independent functions of protein subunits and oligomers are rarely reported.
- Adenovirus E4-ORF1 oncoprotein drives tumorigenesis by interacting with cellular PDZ proteins.
Purpose of the Study:
- To investigate the functional roles of adenovirus E4-ORF1 oncoprotein in its monomeric and trimeric states.
- To identify the specific cellular PDZ proteins that interact with each oligomeric state.
- To elucidate the functional consequences of these distinct interactions.
Main Methods:
- Cellular expression and analysis of adenovirus E4-ORF1 oncoprotein.
- Co-immunoprecipitation assays to identify binding partners.
- Confocal microscopy to assess protein localization.
Main Results:
- Adenovirus E4-ORF1 exists as both monomers and trimers within cells.
- E4-ORF1 monomers sequester MUPP1, MAGI-1, and ZO-2 into insoluble complexes.
- E4-ORF1 trimers bind Dlg1 and promote its plasma membrane translocation.
Conclusions:
- The oligomerization state of E4-ORF1 dictates its binding to distinct PDZ proteins.
- This oligomerization-dependent binding leads to separate functional outcomes.
- This represents a novel mechanism for regulating protein function and cellular processes.
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