SIRT3

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]

SIRT3

NAD-dependent protein deacetylase (PubMed:12186850, PubMed:12374852, PubMed:16788062, PubMed:18680753, PubMed:18794531, PubMed:23283301, PubMed:24121500, PubMed:24252090, PubMed:19535340).
Activates or deactivates mitochondrial target proteins by deacetylating key lysine residues (PubMed:12186850, PubMed:12374852, PubMed:16788062, PubMed:18680753, PubMed:18794531, PubMed:23283301, PubMed:24121500, PubMed:24252090).
Known targets include ACSS1, IDH, GDH, SOD2, PDHA1, LCAD, SDHA and the ATP synthase subunit ATP5PO (PubMed:16788062, PubMed:18680753, PubMed:24121500, PubMed:24252090, PubMed:19535340).
Contributes to the regulation of the cellular energy metabolism (PubMed:24252090).
Important for regulating tissue-specific ATP levels (PubMed:18794531).
In response to metabolic stress, deacetylates transcription factor FOXO3 and recruits FOXO3 and mitochondrial RNA polymerase POLRMT to mtDNA to promote mtDNA transcription (PubMed:23283301).
Acts as a regulator of ceramide metabolism by mediating deacetylation of ceramide synthases CERS1, CERS2 and CERS6, thereby increasing their activity and promoting mitochondrial ceramide accumulation (By similarity).

Biological Process aerobic respirationManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process peptidyl-lysine deacetylationManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process positive regulation of catalase activityManual Assertion Based On ExperimentIDA:CACAO
Biological Process positive regulation of ceramide biosynthetic processISS:UniProtKB
Biological Process positive regulation of superoxide dismutase activityManual Assertion Based On ExperimentIDA:CACAO
Biological Process protein ADP-ribosylationBy SimilarityISS:GO_Central
Biological Process protein deacetylationManual Assertion Based On ExperimentIDA:UniProtKB

Mitochondrion matrix

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