Article

The Human N-Alpha-Acetyltransferase 40 (hNaa40p/hNatD) Is Conserved from Yeast and N-Terminally Acetylates Histones H2A and H4

Ludwig-Maximilians-Universität München, Germany
PLoS ONE (Impact Factor: 3.23). 09/2011; 6(9):e24713. DOI: 10.1371/journal.pone.0024713
Source: PubMed

ABSTRACT

Protein Nα-terminal acetylation (Nt-acetylation) is considered one of the most common protein modification in eukaryotes, and 80-90% of all soluble human proteins are modified in this way, with functional implications ranging from altered protein function and stability to translocation potency amongst others. Nt-acetylation is catalyzed by N-terminal acetyltransferases (NATs), and in yeast five NAT types are identified and denoted NatA-NatE. Higher eukaryotes additionally express NatF. Except for NatD, human orthologues for all yeast NATs are identified. yNatD is defined as the catalytic unit Naa40p (Nat4) which co-translationally Nt-acetylates histones H2A and H4.

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    • "In humans, NatA, NatB and NatC have been identified and reported to function in translation initiation as well as other events in the cell. NatD is a specific N-terminal acetyltransferase of histone H4 and H2A [20]. "
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    • "When the initiator methionine is followed by Asp, Glu, or Gln, it can be acetylated by NatB. NatC acetylates initiator methionines followed by hydrophobic amino acids (Leu, Ile, Tyr, or Phe), NatD acetylates the N-termini of the histones H2A and H4, and NatE acetylates proteins where the initiator methionine is followed by Leu, Ala, Lys, or Met (Polevoda et al. , 2009 ; Hole et al. , 2011 ). Finally, the recently discovered NatF, which is specifi c for higher eukaryotes, acetylates N-termini mainly starting with Met followed by Lys, Leu, Ile, Trp, or Phe (Van Damme et al. , 2011c ). "
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