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SIRT6 exhibits nucleosome-dependent deacetylase activity.

ABSTRACT: The SIRT6 deacetylase is a key regulator of mammalian genome stability, metabolism and lifespan. Previous studies indicated that SIRT6 exhibits poor deacetylase activity in vitro. Here, we explored the specific conditions that allow SIRT6 to function as a significant deacetylase. We show that SIRT6 associates with the nucleosome and deacetylates histones H3 and H4 when they are packaged as nucleosomes, but not as free histones. In contrast, SIRT1 shows the opposite characteristics. Thus, our results show that SIRT6 activity is nucleosome dependent, and suggest that its binding to the nucleosome might convert it into an active structure.

SUBMITTER: Gil R

PROVIDER: S-EPMC3794599 | biostudies-other | 2013 Oct

REPOSITORIES: biostudies-other

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SIRT6 exhibits nucleosome-dependent deacetylase activity.

Gil Reuven R Barth Shaul S Kanfi Yariv Y Cohen Haim Y HY

Nucleic acids research 20130726 18

The SIRT6 deacetylase is a key regulator of mammalian genome stability, metabolism and lifespan. Previous studies indicated that SIRT6 exhibits poor deacetylase activity in vitro. Here, we explored the specific conditions that allow SIRT6 to function as a significant deacetylase. We show that SIRT6 associates with the nucleosome and deacetylates histones H3 and H4 when they are packaged as nucleosomes, but not as free histones. In contrast, SIRT1 shows the opposite characteristics. Thus, our res ...[more]

PMID: 23892288

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