2. Academic Validation
  3. An organellar nα-acetyltransferase, naa60, acetylates cytosolic N termini of transmembrane proteins and maintains Golgi integrity

An organellar nα-acetyltransferase, naa60, acetylates cytosolic N termini of transmembrane proteins and maintains Golgi integrity

  • Cell Rep. 2015 Mar 3;10(8):1362-74. doi: 10.1016/j.celrep.2015.01.053.
Henriette Aksnes 1,  Petra Van Damme 2,  Marianne Goris 1,  Kristian K Starheim 1,  Michaël Marie 1,  Svein Isungset Støve 1,  Camilla Hoel 1,  Thomas Vikestad Kalvik 1,  Kristine Hole 3,  Nina Glomnes 3,  Clemens Furnes 1,  Sonja Ljostveit 1,  Mathias Ziegler 1,  Marc Niere 1,  Kris Gevaert 2,  Thomas Arnesen 4
Affiliations

Affiliations

  • 1 Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway.
  • 2 Department of Medical Protein Research, VIB, 9000 Ghent, Belgium; Department of Biochemistry, Ghent University, 9000 Ghent, Belgium.
  • 3 Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway; Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
  • 4 Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway; Department of Surgery, Haukeland University Hospital, 5021 Bergen, Norway. Electronic address: thomas.arnesen@mbi.uib.no.
PMID: 25732826 DOI: 10.1016/j.celrep.2015.01.053
Abstract

N-terminal acetylation is a major and vital protein modification catalyzed by N-terminal acetyltransferases (NATs). NatF, or Nα-acetyltransferase 60 (Naa60), was recently identified as a NAT in multicellular eukaryotes. Here, we find that Naa60 differs from all other known NATs by its Golgi localization. A new membrane topology assay named PROMPT and a selective membrane permeabilization assay established that Naa60 faces the cytosolic side of intracellular membranes. An Nt-acetylome analysis of NAA60-knockdown cells revealed that Naa60, as opposed to other NATs, specifically acetylates transmembrane proteins and has a preference for N termini facing the cytosol. Moreover, NAA60 knockdown causes Golgi fragmentation, indicating an important role in the maintenance of the Golgi's structural integrity. This work identifies a NAT associated with membranous compartments and establishes N-terminal acetylation as a common modification among transmembrane proteins, a thus-far poorly characterized part of the N-terminal acetylome.

Figures