Caspase-mediated changes in Sir2alpha during apoptosis.

Shizue Ohsawa; Masayuki Miura

doi:10.1016/j.febslet.2006.09.051

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PubMed · 17027980

Caspase-mediated changes in Sir2alpha during apoptosis.

Shizue Ohsawa·Masayuki Miura

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Abstract

Silent information regulator 2 (Sir2) is an NAD(+)-dependent histone deacetylase that establishes repressive chromatin status and extends the life span of both budding yeast and the nematode worm Caenorhabditis elegans. There is growing evidence that its mammalian homologue Sir2alpha protects cells from stress-induced apoptosis. We report here that mammalian Sir2alpha was directly cleaved by both initiator and executioner caspases, and relocated from the nucleus to the cytoplasm in apoptotic cells. These alterations of Sir2alpha were largely inhibited by a caspase-9 dominant-negative mutant or Bcl-xL. Our results indicate that Sir2alpha undergoes dynamic changes in caspase-dependent manner during apoptosis.

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Active Transport, Cell Nucleus Animals Apoptosis Caspase 9 Caspase Inhibitors Caspases Cell Line HeLa Cells Humans Mice Mice, Inbred C57BL Recombinant Proteins Sirtuin 1 Sirtuins Transfection Journal Article Research Support, Non-U.S. Gov't

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Shizue Ohsawa, Masayuki Miura. 2006-10-02. Caspase-mediated changes in Sir2alpha during apoptosis.. https://doi.org/10.1016/j.febslet.2006.09.051

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