SIRT3 Recombinant Protein

This gene encodes a member of the sirtuin family of proteins, homologs to the yeast Sir2 protein. Members of the sirtuin family are characterized by a sirtuin core domain and grouped into four classes. The functions of human sirtuins have not yet been determined; however, yeast sirtuin proteins are known to regulate epigenetic gene silencing and suppress recombination of rDNA. Studies suggest that the human sirtuins may function as intracellular regulatory proteins with mono-ADP-ribosyltransferase activity. The protein encoded by this gene is included in class I of the sirtuin family. Two alternatively spliced transcript variants that encode different proteins have been described for this gene. [provided by RefSeq, Jul 2008]

Function: NAD-dependent protein deacetylase. Activates mitochondrial target proteins, including ACSS1, IDH2 and GDH by deacetylating key lysine residues. Contributes to the regulation of the cellular energy metabolism. Important for regulating tissue-specific ATP levels. Ref.9 Ref.11 Ref.12 Ref.14

Catalytic activity: NAD+ + an acetylprotein = nicotinamide + O-acetyl-ADP-ribose + a protein. Ref.6 Ref.7 Ref.9

Cofactor: Binds 1 zinc ion per subunit.

Subunit structure: Interacts with NDUFA9, ACSS1, IDH2 and GDH. Ref.9 Ref.12

Subcellular location: Mitochondrion matrix Ref.6 Ref.7 Ref.8 Ref.10.

Tissue specificity: Widely expressed. Ref.1 Ref.7

Post-translational modification: Processed by mitochondrial processing peptidase (MPP) to give a 28 kDa product. Such processing is probably essential for its enzymatic activity.

Miscellaneous: Has some ability to deacetylate histones in vitro, but seeing its subcellular location, this is unlikely in vivo.

Sequence similarities: Belongs to the sirtuin family. Class I subfamily.Contains 1 deacetylase sirtuin-type domain.

Biophysicochemical propertiesKinetic parameters:KM=600 µM for NAD Ref.14