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Updated: Aug 4, 2026
08:18
Focus Formation: A Cell-based Assay to Determine the Oncogenic Potential of a Gene
Published on: December 31, 2014
The Mdm2 oncoprotein interacts with the cell fate regulator Numb
T Juven-Gershon1, O Shifman, T Unger
1Department of Molecular Cell Biology, The Weizmann Institute of Science, Rehovot 76100, Israel.
Molecular and Cellular Biology
|June 25, 1998
Summary
The Mdm2 oncoprotein interacts with Numb, a cell fate protein, independent of p53. This interaction influences Numb localization and levels, potentially affecting tumor cell differentiation and survival.
Area of Science:
- Oncology
- Molecular Biology
- Cell Biology
Background:
- The Mdm2 oncoprotein is a known inhibitor of the p53 tumor suppressor.
- Mdm2 may possess functions independent of p53.
- Numb is a protein critical for cell fate determination.
Purpose of the Study:
- To identify p53-independent activities of Mdm2.
- To investigate potential interactions between Mdm2 and other cellular proteins.
Main Methods:
- Yeast two-hybrid screen to identify Mdm2-binding proteins.
- In vitro assays.
- Transfected cell studies.
Main Results:
- Mdm2 was found to associate with Numb.
- This association promotes the nuclear translocation of overexpressed Numb.
- Cellular Numb levels were reduced upon Mdm2 interaction.
Conclusions:
- Mdm2 interacts with Numb in a p53-independent manner.
- Mdm2 binding influences Numb's subcellular localization and stability.
- Mdm2-Numb interaction may impact cell differentiation and survival, contributing to tumor cell characteristics.
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