The Arabidopsis Class II Sirtuin Is a Lysine Deacetylase and Interacts with Mitochondrial Energy Metabolism

authored by

Ann Christine König, Markus Hartl, Phuong Anh Pham, Miriam Laxa, Paul J. Boersema, Anne Orwat, Ievgeniia Kalitventseva, Magdalena Plöchinger, Hans Peter Braun, Dario Leister, Matthias Mann, Andreas Wachter, Alisdair R. Fernie, Iris Finkemeier

Abstract

The posttranslational regulation of proteins by lysine (Lys) acetylation has recently emerged to occur not only on histones, but also on organellar proteins in plants and animals. In particular, the catalytic activities of metabolic enzymes have been shown to be regulated by Lys acetylation. The Arabidopsis (Arabidopsis thaliana) genome encodes two predicted sirtuin-type Lys deacetylases, of which only Silent Information Regulator2 homolog (SRT2) contains a predicted presequence for mitochondrial targeting. Here, we have investigated the function of SRT2 in Arabidopsis. We demonstrate that SRT2 functions as a Lys deacetylase in vitro and in vivo. We show that SRT2 resides predominantly at the inner mitochondrial membrane and interacts with a small number of protein complexes mainly involved in energy metabolism and metabolite transport. Several of these protein complexes, such as the ATP synthase and the ATP/ADP carriers, show an increase in Lys acetylation in srt2 loss-of-function mutants. The srt2 plants display no growth phenotype but rather a metabolic phenotype with altered levels in sugars, amino acids, and ADP contents. Furthermore, coupling of respiration to ATP synthesis is decreased in these lines, while the ADP uptake into mitochondria is significantly increased. Our results indicate that SRT2 is important in fine-tuning mitochondrial energy metabolism.

Organisation(s)

Institute of Plant Genetics

External Organisation(s)

Ludwig-Maximilians-Universität München (LMU)
Max Planck Institute of Molecular Plant Physiology (MPI-MP)
Max Planck Institute of Biochemistry (MPIB)
University of Tübingen

Type

Article

Journal

Plant physiology

Volume

164

Pages

1401-1414

No. of pages

14

ISSN

0032-0889

Publication date

03.2014

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Physiology, Genetics, Plant Science

Electronic version(s)

https://doi.org/10.1104/pp.113.232496 (Access: Open)
https://doi.org/10.15488/11684 (Access: Open)