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Label-free quantitative proteomics of the lysine acetylome in mitochondria identifies substrates of SIRT3 in metabolic pathways.

ABSTRACT: Large-scale proteomic approaches have identified numerous mitochondrial acetylated proteins; however in most cases, their regulation by acetyltransferases and deacetylases remains unclear. Sirtuin 3 (SIRT3) is an NAD(+)-dependent mitochondrial protein deacetylase that has been shown to regulate a limited number of enzymes in key metabolic pathways. Here, we use a rigorous label-free quantitative MS approach (called MS1 Filtering) to analyze changes in lysine acetylation from mouse liver mitochondria in the absence of SIRT3. Among 483 proteins, a total of 2,187 unique sites of lysine acetylation were identified after affinity enrichment. MS1 Filtering revealed that lysine acetylation of 283 sites in 136 proteins was significantly increased in the absence of SIRT3 (at least twofold). A subset of these sites was independently validated using selected reaction monitoring MS. These data show that SIRT3 regulates acetylation on multiple proteins, often at multiple sites, across several metabolic pathways including fatty acid oxidation, ketogenesis, amino acid catabolism, and the urea and tricarboxylic acid cycles, as well as mitochondrial regulatory proteins. The widespread modification of key metabolic pathways greatly expands the number of known substrates and sites that are targeted by SIRT3 and establishes SIRT3 as a global regulator of mitochondrial protein acetylation with the capability of coordinating cellular responses to nutrient status and energy homeostasis.

SUBMITTER: Rardin MJ

PROVIDER: S-EPMC3631688 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Label-free quantitative proteomics of the lysine acetylome in mitochondria identifies substrates of SIRT3 in metabolic pathways.

Rardin Matthew J MJ Newman John C JC Held Jason M JM Cusack Michael P MP Sorensen Dylan J DJ Li Biao B Schilling Birgit B Mooney Sean D SD Kahn C Ronald CR Verdin Eric E Gibson Bradford W BW

Proceedings of the National Academy of Sciences of the United States of America 20130401 16

Large-scale proteomic approaches have identified numerous mitochondrial acetylated proteins; however in most cases, their regulation by acetyltransferases and deacetylases remains unclear. Sirtuin 3 (SIRT3) is an NAD(+)-dependent mitochondrial protein deacetylase that has been shown to regulate a limited number of enzymes in key metabolic pathways. Here, we use a rigorous label-free quantitative MS approach (called MS1 Filtering) to analyze changes in lysine acetylation from mouse liver mitochon ...[more]

PMID: 23576753

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Dataset Information

Label-free quantitative proteomics of the lysine acetylome in mitochondria identifies substrates of SIRT3 in metabolic pathways.

Publications

Label-free quantitative proteomics of the lysine acetylome in mitochondria identifies substrates of SIRT3 in metabolic pathways.

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