Publications

• The human N-alpha-acetyltransferase 40 (hNaa40p/hNatD) is conserved from yeast and N-terminally acetylates histones H2A and H4.

  Hole K., Van Damme P., Dalva M., Aksnes H., Glomnes N., Varhaug J.E., Lillehaug J.R., Gevaert K., Arnesen T.

  Protein N(α)-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 a ... >> More

  Protein N(α)-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. In this study we identified and characterized hNaa40p/hNatD, the human orthologue of the yeast Naa40p. An in vitro proteome-derived peptide library Nt-acetylation assay indicated that recombinant hNaa40p acetylates N-termini starting with the consensus sequence Ser-Gly-Gly-Gly-Lys-, strongly resembling the N-termini of the human histones H2A and H4. This was confirmed as recombinant hNaa40p Nt-acetylated the oligopeptides derived from the N-termini of both histones. In contrast, a synthetically Nt-acetylated H4 N-terminal peptide with all lysines being non-acetylated, was not significantly acetylated by hNaa40p, indicating that hNaa40p catalyzed H4 N(α)-acetylation and not H4 lysine N(ε)-acetylation. Also, immunoprecipitated hNaa40p specifically Nt-acetylated H4 in vitro. Heterologous expression of hNaa40p in a yeast naa40-Δ strain restored Nt-acetylation of yeast histone H4, but not H2A in vivo, probably reflecting the fact that the N-terminal sequences of human H2A and H4 are highly similar to each other and to yeast H4 while the N-terminal sequence of yeast H2A differs. Thus, Naa40p seems to have co-evolved with the human H2A sequence. Finally, a partial co-sedimentation with ribosomes indicates that hNaa40p co-translationally acetylates H2A and H4. Combined, our results strongly suggest that human Naa40p/NatD is conserved from yeast. Thus, the NATs of all classes of N-terminally acetylated proteins in humans now appear to be accounted for. << Less

  PLoS ONE 6:E24713-E24713(2011) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• An Nalpha-acetyltransferase responsible for acetylation of the N-terminal residues of histones H4 and H2A.

  Song O.-K., Wang X., Waterborg J.H., Sternglanz R.

  A yeast gene has been identified that encodes a novel, evolutionarily conserved Nalpha-acetyltransferase responsible for acetylation of the N-terminal residues of histones H4 and H2A. The gene has been named NAT4. Recombinant Nat4 protein acetylated a peptide corresponding to the N-terminal tail o ... >> More

  A yeast gene has been identified that encodes a novel, evolutionarily conserved Nalpha-acetyltransferase responsible for acetylation of the N-terminal residues of histones H4 and H2A. The gene has been named NAT4. Recombinant Nat4 protein acetylated a peptide corresponding to the N-terminal tail of H4, but not an H3 peptide nor the peptide adrenocorticotropin. H4 and H2A are N-terminally acetylated in all species from yeast to mammals and hence blocked from sequencing by Edman degradation. In contrast, H4 and H2A purified from a nat4 mutant were unacetylated and could be sequenced. Analysis of yeast histones by acid-urea gel electrophoresis showed that all the H4 and H2A from the mutant migrated more rapidly than the same histones from a wild type strain, consistent with the histones from the mutant having one extra positive charge due to one less acetylated amino group. A comparison of yeast proteins from wild type and a nat4 mutant by two-dimensional gel electrophoresis showed no evidence that other yeast proteins are substrates of this acetyltransferase. Thus, Nat4 may be dedicated specifically to the N-terminal acetylation of histones H4 and H2A. Surprisingly, nat4 mutants grow at a normal rate and have no readily observable phenotypes. << Less

  J. Biol. Chem. 278:38109-38112(2003) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• The molecular basis for histone H4- and H2A-specific amino-terminal acetylation by NatD.

  Magin R.S., Liszczak G.P., Marmorstein R.

  N-terminal acetylation is among the most common protein modifications in eukaryotes and is mediated by evolutionarily conserved N-terminal acetyltransferases (NATs). NatD is among the most selective NATs; its only known substrates are histones H4 and H2A, containing the N-terminal sequence SGRGK i ... >> More

  N-terminal acetylation is among the most common protein modifications in eukaryotes and is mediated by evolutionarily conserved N-terminal acetyltransferases (NATs). NatD is among the most selective NATs; its only known substrates are histones H4 and H2A, containing the N-terminal sequence SGRGK in humans. Here we characterize the molecular basis for substrate-specific acetylation by NatD by reporting its crystal structure bound to cognate substrates and performing related biochemical studies. A novel N-terminal segment wraps around the catalytic core domain to make stabilizing interactions, and the α1-α2 and β6-β7 loops adopt novel conformations to properly orient the histone N termini in the binding site. Ser1 and Arg3 of the histone make extensive contacts to highly conserved NatD residues in the substrate binding pocket, and flanking glycine residues also appear to contribute to substrate-specific binding by NatD, together defining a Ser-Gly-Arg-Gly recognition sequence. These studies have implications for understanding substrate-specific acetylation by NAT enzymes. << Less

  Structure 23:332-341(2015) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Properties of Nat4, an N(alpha)-acetyltransferase of Saccharomyces cerevisiae that modifies N termini of histones H2A and H4.

  Polevoda B., Hoskins J., Sherman F.

  Nat4, also designated NatD, was previously shown to acetylate the N termini of histones H2A and H4, which have SGGKG and SGRGK N termini (O. K. Song, X. Wang, J. H. Waterborg, and R. Sternglanz, J. Biol. Chem. 278:38109-38112, 2003). The analysis of chimeric proteins with various N-terminal segmen ... >> More

  Nat4, also designated NatD, was previously shown to acetylate the N termini of histones H2A and H4, which have SGGKG and SGRGK N termini (O. K. Song, X. Wang, J. H. Waterborg, and R. Sternglanz, J. Biol. Chem. 278:38109-38112, 2003). The analysis of chimeric proteins with various N-terminal segments of histone H4 fused to iso-1-cytochrome c revealed that efficient acetylation by NatD required at least 30 to 50 amino acid residues of the N terminus of histone H4. This requirement for an extended N terminus is in marked contrast with the major N-terminal acetyl transferases (NATs), i.e., NatA, NatB, and NatC, which require as few as two specific residues and usually no more than four or five. However, similar to the other NATs, NatD is associated with ribosomes. The nat4-Delta strain showed several minor phenotypes, including sensitivity to 3-aminotriazole, benomyl, and thiabendazole. Moreover, these nat4-Delta phenotypes were enhanced in the strain containing K5R K8R K12R replacements in the N-tail of histone H4, suggesting that the lack of N-terminal serine acetylation is synergistic to the lack of acetylation of the H4 N-tail lysines. Thus, N-terminal serine acetylation of histone H4 may be a part of an essential charge patch first described for the histone H2A.Z variant in Tetrahymena species. << Less

  Mol Cell Biol 29:2913-2924(2009) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.