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Deacetylation Assays to Unravel the Interplay between Sirtuins SIRT2 and Specific Protein-substrates
Published on: February 27, 2016
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Nuclear-localized SIRT1 inhibits apoptosis via deacetylating p53
1MOE Key Laboratory of Laser Life Science, College of Biophotonics, School of Optoelectronic Science and Engineering, South China Normal University, Guangzhou, Guangdong 510631, China; Guangdong Provincial Key Laboratory of Laser Life Science, College of Biophotonics, School of Optoelectronic Science and Engineering, South China Normal University, Guangzhou, Guangdong 510631, China.
The International Journal of Biochemistry & Cell Biology
|August 2, 2025
Summary
Nuclear-localized SIRT1 inhibits apoptosis by deacetylating p53, while cytoplasmic SIRT1 promotes apoptosis. Silencing p53 compromises SIRT1
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The role of Sirtuin 1 (SIRT1) in apoptosis is debated.
- SIRT1's subcellular localization may determine its function in apoptosis.
Purpose of the Study:
- To investigate the distinct roles of nuclear and cytoplasmic SIRT1 in STS/DOX-induced apoptosis.
- To elucidate the mechanism by which nuclear SIRT1 influences apoptosis, particularly its interaction with p53.
Main Methods:
- Western blot analysis to assess protein expression and modification (Ac-p53).
- Fluorescence resonance energy transfer (FRET) to study protein-protein interactions in vivo.
- Manipulation of nuclear-localized SIRT1 and cytoplasmic-localized SIRT1 levels via silencing and overexpression.
Main Results:
- Nuclear SIRT1 overexpression inhibited apoptosis, while silencing enhanced it, indicating an anti-apoptotic role.
- Cytoplasmic SIRT1 overexpression promoted apoptosis, demonstrating a pro-apoptotic function.
- Nuclear SIRT1 deacetylated p53, inhibiting apoptosis; this effect was dependent on p53.
- STS treatment enhanced the direct interaction between nuclear SIRT1 and p53.
Conclusions:
- Nuclear-localized SIRT1 inhibits apoptosis through p53 deacetylation.
- Cytoplasmic-localized SIRT1 promotes apoptosis.
- SIRT1's function in apoptosis is critically dependent on its subcellular localization and interaction with p53.
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