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Cycloheximide Chase Analysis of Protein Degradation in Saccharomyces cerevisiae
Published on: April 18, 2016
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Ubiquitin-mediated regulation of APE2 protein abundance
Anne McMahon1, Jianjun Zhao2, Shan Yan3
1Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, North Carolina, USA.
The Journal of Biological Chemistry
|May 5, 2024
Summary
This study reveals that the protein APE2 is degraded through ubiquitination, a key process for maintaining genomic stability. This discovery identifies a new regulatory pathway for APE2 in cancer cells.
Area of Science:
- Molecular Biology
- Biochemistry
- Cancer Research
Background:
- APE2 is crucial for genomic and epigenomic stability, involved in DNA repair and damage response.
- APE2 is upregulated in various cancers, correlating with patient survival rates.
- The regulatory mechanisms controlling APE2 protein levels remain largely unknown.
Purpose of the Study:
- To investigate the posttranslational modifications regulating APE2 protein abundance.
- To elucidate the pathway responsible for APE2 degradation.
- To identify the E3 ubiquitin ligase responsible for APE2 ubiquitination.
Main Methods:
- Ubiquitination assays to detect poly-ubiquitinated APE2.
- Western blotting to assess APE2 protein levels and degradation.
- In vitro and in vivo assays to identify the E3 ubiquitin ligase and key ubiquitination residue.
Main Results:
- APE2 undergoes K48-linked poly-ubiquitination and subsequent degradation via the ubiquitin-proteasome system.
- Lysine residue K371 in APE2 is essential for its ubiquitination and degradation.
- MKRN3 is identified as the E3 ubiquitin ligase that targets APE2 for ubiquitination.
Conclusions:
- This study defines the APE2 proteostasis network, revealing its regulation by ubiquitination and degradation.
- The findings provide a foundation for understanding APE2's role in genome integrity and cancer.
- Targeting the APE2 ubiquitination pathway may offer new therapeutic strategies for cancer treatment.
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