Program in Gene Function and Expression; Program in Molecular Medicine; Program in Bioinformatics and Integrative Biology; Department of Cancer Biology
Biochemistry | Cell Biology | Cellular and Molecular Physiology | Genetics and Genomics
Adenosine triphosphate (ATP) synthase beta, the catalytic subunit of mitochondrial complex V, synthesizes ATP. We show that ATP synthase beta is deacetylated by a human nicotinamide adenine dinucleotide (NAD(+))-dependent protein deacetylase, sirtuin 3, and its Drosophila melanogaster homologue, dSirt2. dsirt2 mutant flies displayed increased acetylation of specific Lys residues in ATP synthase beta and decreased complex V activity. Overexpression of dSirt2 increased complex V activity. Substitution of Lys 259 and Lys 480 with Arg in human ATP synthase beta, mimicking deacetylation, increased complex V activity, whereas substitution with Gln, mimicking acetylation, decreased activity. Mass spectrometry and proteomic experiments from wild-type and dsirt2 mitochondria identified the Drosophila mitochondrial acetylome and revealed dSirt2 as an important regulator of mitochondrial energy metabolism. Additionally, we unravel a ceramide-NAD(+)-sirtuin axis wherein increased ceramide, a sphingolipid known to induce stress responses, resulted in depletion of NAD(+) and consequent decrease in sirtuin activity. These results provide insight into sirtuin-mediated regulation of complex V and reveal a novel link between ceramide and Drosophila acetylome.
Rights and Permissions
Citation: Rahman M, Nirala NK, Singh A, Zhu LJ, Taguchi K, Bamba T, Fukusaki E, Shaw LM, Lambright DG, Acharya JK, Acharya UR. Drosophila Sirt2/mammalian SIRT3 deacetylates ATP synthase β and regulates complex V activity. J Cell Biol. 2014 Jul 21;206(2):289-305. doi: 10.1083/jcb.201404118. Link to article on publisher's site