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Updated: May 9, 2026
14:32
Deacetylation Assays to Unravel the Interplay between Sirtuins (SIRT2) and Specific Protein-substrates
Published on: February 27, 2016
SIRT6 exhibits nucleosome-dependent deacetylase activity
Reuven Gil1, Shaul Barth, Yariv Kanfi
1The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
Nucleic Acids Research
|July 30, 2013
Summary
Sirtuin 6 (SIRT6) deacetylase activity is nucleosome-dependent. SIRT6 deacetylates histones H3 and H4 only when they are part of nucleosomes, unlike SIRT1, suggesting nucleosome binding activates SIRT6.
Area of Science:
- Biochemistry
- Molecular Biology
- Genetics
Background:
- Sirtuin 6 (SIRT6) is crucial for genome stability, metabolism, and lifespan in mammals.
- Previous research suggests SIRT6 has limited deacetylase activity in vitro.
- Understanding SIRT6's functional conditions is vital for its therapeutic potential.
Purpose of the Study:
- To investigate the specific conditions required for SIRT6 to exhibit significant deacetylase activity.
- To elucidate the role of nucleosomes in regulating SIRT6 function.
- To compare SIRT6's activity with SIRT1 under different substrate conditions.
Main Methods:
- In vitro biochemical assays to assess deacetylase activity.
- Analysis of SIRT6 and SIRT1 interactions with nucleosomes and free histones.
- Histone deacetylase (HDAC) activity assays.
Main Results:
- SIRT6 deacetylates histones H3 and H4 specifically when they are packaged within nucleosomes.
- SIRT6 does not deacetylate free histones.
- SIRT1 displays distinct substrate preferences compared to SIRT6, not being nucleosome-dependent.
Conclusions:
- SIRT6's deacetylase activity is intrinsically dependent on its association with nucleosomes.
- Nucleosome binding appears to be a critical factor in activating SIRT6's enzymatic function.
- These findings offer new insights into the regulation of SIRT6 and its role in cellular processes.
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