Proteomic investigations of lysine acetylation identify diverse substrates of mitochondrial deacetylase sirt3

TY - JOUR

T1 - Proteomic investigations of lysine acetylation identify diverse substrates of mitochondrial deacetylase sirt3

AU - Sol, E-ri Maria

AU - Wagner, Sebastian A

AU - Weinert, Brian T

AU - Kumar, Amit

AU - Kim, Hyun-Seok

AU - Deng, Chu-Xia

AU - Choudhary, Chuna Ram

PY - 2012/12/7

Y1 - 2012/12/7

N2 - Lysine acetylation is a posttranslational modification that is dynamically regulated by the activity of acetyltransferases and deacetylases. The human and mouse genomes encode 18 different lysine deacetylases (KDACs) which are key regulators of many cellular processes. Identifying substrates of KDACs and pinpointing the regulated acetylation sites on target proteins may provide important information about the molecular basis of their functions. Here we apply quantitative proteomics to identify endogenous substrates of the mitochondrial deacetylase Sirtuin 3 (Sirt3) by comparing site-specific acetylation in wild-type murine embryonic fibroblasts to Sirt3 knockout cells. We confirm Sirt3-regulated acetylation of several mitochondrial proteins in human cells by comparing acetylation in U2OS cells overexpressing Sirt3 to U2OS cells in which Sirt3 expression was reduced by shRNA. Our data demonstrate that ablation of Sirt3 significantly increases acetylation at dozens of sites on mitochondrial proteins. Substrates of Sirt3 are implicated in various metabolic pathways, including fatty acid metabolism and the tricarboxylic acid cycle. These results imply broader regulatory roles of Sirt3 in the mitochondria by modulating acetylation on diverse substrates. The experimental strategy described here is generic and can be applied to identify endogenous substrates of other lysine deacetylases.

AB - Lysine acetylation is a posttranslational modification that is dynamically regulated by the activity of acetyltransferases and deacetylases. The human and mouse genomes encode 18 different lysine deacetylases (KDACs) which are key regulators of many cellular processes. Identifying substrates of KDACs and pinpointing the regulated acetylation sites on target proteins may provide important information about the molecular basis of their functions. Here we apply quantitative proteomics to identify endogenous substrates of the mitochondrial deacetylase Sirtuin 3 (Sirt3) by comparing site-specific acetylation in wild-type murine embryonic fibroblasts to Sirt3 knockout cells. We confirm Sirt3-regulated acetylation of several mitochondrial proteins in human cells by comparing acetylation in U2OS cells overexpressing Sirt3 to U2OS cells in which Sirt3 expression was reduced by shRNA. Our data demonstrate that ablation of Sirt3 significantly increases acetylation at dozens of sites on mitochondrial proteins. Substrates of Sirt3 are implicated in various metabolic pathways, including fatty acid metabolism and the tricarboxylic acid cycle. These results imply broader regulatory roles of Sirt3 in the mitochondria by modulating acetylation on diverse substrates. The experimental strategy described here is generic and can be applied to identify endogenous substrates of other lysine deacetylases.

KW - Acetylation

KW - Animals

KW - Cell Line

KW - Fibroblasts

KW - Humans

KW - Lysine

KW - Mice

KW - Mice, Knockout

KW - Mitochondria

KW - Proteomics

KW - Sirtuin 3

U2 - 10.1371/journal.pone.0050545

DO - 10.1371/journal.pone.0050545

M3 - Journal article

C2 - 23236377

SN - 1932-6203

VL - 7

SP - e50545

JO - PLoS Computational Biology

JF - PLoS Computational Biology

IS - 12

ER -