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Updated: Jun 23, 2026
14:57
Yeast As a Chassis for Developing Functional Assays to Study Human P53
Published on: August 4, 2019
C-Abl as a modulator of p53
Yaara Levav-Cohen1, Zehavit Goldberg, Valentina Zuckerman
1Lautenberg Center for General and Tumor Immunology, The Hebrew University Hadassah Medical School, Jerusalem 91120, Israel.
Summary
The p53-Mdm2 loop regulates cellular responses to DNA damage. C-Abl protein protects p53, while its oncogenic form, Bcr-Abl, counteracts p53
Area of Science:
- Cellular Biology
- Molecular Oncology
- Cancer Research
Background:
- The tumor suppressor p53 is crucial for DNA integrity, with its activity tightly regulated by inhibitors like Mdm2.
- The p53-Mdm2 feedback loop is a key pathway for cellular stress responses.
- Mdm2 inhibits p53's transcriptional activity and promotes its degradation.
Purpose of the Study:
- To elucidate the role of c-Abl and its oncogenic form, Bcr-Abl, in modulating the p53-Mdm2 regulatory loop.
- To understand how these proteins influence p53 accumulation and activity in response to cellular stress.
Main Methods:
- Investigated the interaction between c-Abl, Mdm2, and p53.
- Analyzed the effects of c-Abl and Bcr-Abl on p53 stability and function.
- Examined p53 responses to DNA damage in the presence of these proteins.
Main Results:
- C-Abl antagonizes Mdm2, promoting p53 accumulation and activity following DNA damage.
- C-Abl also protects p53 from other inhibitors like the HPV-E6/E6AP complex.
- Bcr-Abl, while promoting p53 accumulation, counteracts its growth-inhibitory functions by altering the p53-Mdm2 loop.
Conclusions:
- C-Abl plays a vital role in enhancing p53-mediated tumor suppression.
- Oncogenic Bcr-Abl has a complex effect, promoting p53 accumulation but inhibiting its tumor-suppressive functions.
- Modulation of the p53-Mdm2 loop by c-Abl and Bcr-Abl critically influences cellular responses to DNA damage and cancer development.
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