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SIRT3, a human SIR2 homologue, is an NAD-dependent deacetylase localized to mitochondria.

ABSTRACT: The SIR2 (silent information regulator 2) gene family has diverse functions in yeast including gene silencing, DNA repair, cell-cycle progression, and chromosome fidelity in meiosis and aging. Human homologues, termed sirtuins, are highly conserved but are of unknown function. We previously identified a large imprinted gene domain on 11p15.5 and investigated the 11p15.5 sirtuin SIRT3. Although this gene was not imprinted, we found that it is localized to mitochondria, with a mitochondrial targeting signal within a unique N-terminal peptide sequence. The encoded protein was found also to possess NAD(+)-dependent histone deacetylase activity. These results suggest a previously unrecognized organelle for sirtuin function and that the role of SIRT3 in mitochondria involves protein deacetylation.

SUBMITTER: Onyango P

PROVIDER: S-EPMC129731 | biostudies-literature | 2002 Oct

REPOSITORIES: biostudies-literature

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SIRT3, a human SIR2 homologue, is an NAD-dependent deacetylase localized to mitochondria.

Onyango Patrick P Celic Ivana I McCaffery J Michael JM Boeke Jef D JD Feinberg Andrew P AP

Proceedings of the National Academy of Sciences of the United States of America 20021008 21

The SIR2 (silent information regulator 2) gene family has diverse functions in yeast including gene silencing, DNA repair, cell-cycle progression, and chromosome fidelity in meiosis and aging. Human homologues, termed sirtuins, are highly conserved but are of unknown function. We previously identified a large imprinted gene domain on 11p15.5 and investigated the 11p15.5 sirtuin SIRT3. Although this gene was not imprinted, we found that it is localized to mitochondria, with a mitochondrial target ...[more]

PMID: 12374852

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