Sir2p exists in two nucleosome‐binding complexes with distinct deacetylase activities

@article{Ghidelli2001Sir2pEI,
  title={Sir2p exists in two nucleosome‐binding complexes with distinct deacetylase activities},
  author={S. Ghidelli and D. Donze and N. Dhillon and R. Kamakaka},
  journal={The EMBO Journal},
  year={2001},
  volume={20}
}
The absolute requirement for the histone deacetylase activity of Sir2p in silencing coupled with the conservation of Sir2p‐like proteins in larger eukaryotes suggests that this molecule plays an important role in gene regulation in all organisms. Here we report the purification and characterization of two Sir2p‐containing protein complexes; one of which contains Sir4p and the other Net1p. The Sir4p‐containing complex has an NAD‐dependent histone deacetylase activity, while the Net1p‐containing… Expand
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It is concluded that histone deacetylation is not sufficient for the full recruitment of silencing proteins to chromatin and that Sir-Sir interactions are essential for the assembly of heterochromatin. Expand
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TLDR
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