title: Proteins of diverse function and subcellular location are lysine acetylated in Arabidopsis.
abstract: Acetylation of the ε-amino group of lysine (Lys) is a reversible posttranslational modification recently discovered to be widespread, occurring on proteins outside the nucleus, in most subcellular locations in mammalian cells. Almost nothing is known about this modification in plants beyond the well-studied acetylation of histone proteins in the nucleus. Here, we report that Lys acetylation in plants also occurs on organellar and cytosolic proteins. We identified 91 Lys-acetylated sites on 74 proteins of diverse functional classes. Furthermore, our study suggests that Lys acetylation may be an important posttranslational modification in the chloroplast, since four Calvin cycle enzymes were acetylated. The plastid-encoded large subunit of Rubisco stands out because of the large number of acetylated sites occurring at important Lys residues that are involved in Rubisco tertiary structure formation and catalytic function. Using the human recombinant deacetylase sirtuin 3, it was demonstrated that Lys deacetylation significantly affects Rubisco activity as well as the activities of other central metabolic enzymes, such as the Calvin cycle enzyme phosphoglycerate kinase, the glycolytic enzyme glyceraldehyde 3-phosphate dehydrogenase, and the tricarboxylic acid cycle enzyme malate dehydrogenase. Our results demonstrate that Lys acetylation also occurs on proteins outside the nucleus in Arabidopsis (Arabidopsis thaliana) and that Lys acetylation could be important in the regulation of key metabolic enzymes.
authors.affiliation: Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom.
authors.forename: Iris
authors.initials: I
authors.lastname: Finkemeier
authors.forename: Miriam
authors.initials: M
authors.lastname: Laxa
authors.forename: Laurent
authors.initials: L
authors.lastname: Miguet
authors.forename: Andrew J M
authors.initials: AJ
authors.lastname: Howden
authors.forename: Lee J
authors.initials: LJ
authors.lastname: Sweetlove
mesh_terms: D000107:Acetylation; D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism; D002853:Chromatography, Liquid; D008239:Lysine / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism; D010788:Photosynthesis; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D020543:Proteome / Q000032:analysis; D012273:Ribulose-Bisphosphate Carboxylase / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D029681:Arabidopsis Proteins; D020543:Proteome; D012273:Ribulose-Bisphosphate Carboxylase; D008239:Lysine