Molecular identification and functional characterization of the first Nα-acetyltransferase in plastids by global acetylome profiling

• Verfasst von: Trinh, Dinh-Van [VerfasserIn]
• Verfasst von: Linster, Eric [VerfasserIn]
• Verfasst von: Feldman-Salit, Anna [VerfasserIn]
• Verfasst von: Hell, Rüdiger [VerfasserIn]
• Verfasst von: Wirtz, Markus [VerfasserIn]
• Titel: Molecular identification and functional characterization of the first Nα-acetyltransferase in plastids by global acetylome profiling
• Verf.angabe: Trinh V. Dinh, Willy V. Bienvenut, Eric Linster, Anna Feldman-Salit, Vincent A. Jung, Thierry Meinnel, Rüdiger Hell, Carmela Giglione and Markus Wirtz
• E-Jahr: 2015
• Jahr: April 30, 2015
• Umfang: 10 S.
• Fussnoten: Gesehen am 19.05.2017
• Titel Quelle: Enthalten in: Proteomics
• Ort Quelle: Weinheim : Wiley VCH, 2001
• Jahr Quelle: 2015
• Band/Heft Quelle: 15(2015), 14, Seite 2426-2435
• ISSN Quelle: 1615-9861
• DOI: doi:10.1002/pmic.201500025
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Arabidopsis thaliana
• Sach-SW: AtNAA70
• Sach-SW: Chloroplast
• Sach-SW: Nα-acetyltransferase
• Sach-SW: Plant proteomics
• K10plus-PPN: 1558823417

Abstract

Protein Nα-terminal acetylation represents one of the most abundant protein modifications of higher eukaryotes. In humans, six Nα-acetyltransferases (Nats) are responsible for the acetylation of approximately 80% of the cytosolic proteins. N-terminal protein acetylation has not been evidenced in organelles of metazoans, but in higher plants is a widespread modification not only in the cytosol but also in the chloroplast. In this study, we identify and characterize the first organellar-localized Nat in eukaryotes. A primary sequence-based search in Arabidopsis thaliana revealed seven putatively plastid-localized Nats of which AT2G39000 (AtNAA70) showed the highest conservation of the acetyl-CoA binding pocket. The chloroplastic localization of AtNAA70 was demonstrated by transient expression of AtNAA70:YFP in Arabidopsis mesophyll protoplasts. Homology modeling uncovered a significant conservation of tertiary structural elements between human HsNAA50 and AtNAA70. The in vivo acetylation activity of AtNAA70 was demonstrated on a number of distinct protein Nα-termini with a newly established global acetylome profiling test after expression of AtNAA70 in E. coli. AtNAA70 predominately acetylated proteins starting with M, A, S and T, providing an explanation for most protein N-termini acetylation events found in chloroplasts. Like HsNAA50, AtNAA70 displays Nε-acetyltransferase activity on three internal lysine residues. All MS data have been deposited in the ProteomeXchange with identifier PXD001947 (http://proteomecentral.proteomexchange.org/dataset/PXD001947).