title: Diversity in the Sir2 family of protein deacetylases.
abstract: The silent information regulator (Sir2) family of protein deacetylases (Sirtuins) are nicotinamide adenine dinucleotide (NAD)(+)-dependent enzymes that hydrolyze one molecule of NAD(+) for every lysine residue that is deacetylated. The Sirtuins are phylogenetically conserved in eukaryotes, prokaryotes, and Archeal species. Prokaryotic and Archeal species usually have one or two Sirtuin homologs, whereas eukaryotes typically have multiple versions. The founding member of this protein family is the Sir2 histone deacetylase of Saccharomyces cerevisiae, which is absolutely required for transcriptional silencing in this organism. Sirtuins in other organisms often have nonhistone substrates and in eukaryotes, are not always localized in the nucleus. The diversity of substrates is reflected in the various biological activities that Sirtuins function, including development, metabolism, apoptosis, and heterochromatin formation. This review emphasizes the great diversity in Sirtuin function and highlights its unusual catalytic properties.
authors.affiliation: Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Jordan Hall, Box 800733, Charlottesville, VA 22908, USA.
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Buck
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Gallo
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Smith
mesh_terms: D000595:Amino Acid Sequence; D006655:Histone Deacetylases / Q000502:physiology; D006801:Humans; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae / Q000502:physiology; D056565:Sirtuin 2; D037761:Sirtuins / Q000502:physiology*
chemical_list: D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae; C087778:SIR2 protein, S cerevisiae; D056565:Sirtuin 2; D037761:Sirtuins; D006655:Histone Deacetylases