title: Functional and physical interactions between yeast 14-3-3 proteins, acetyltransferases, and deacetylases in response to DNA replication perturbations.
abstract: The highly conserved 14-3-3 proteins participate in many biological processes in different eukaryotes. The BMH1 and BMH2 genes encode the two functionally redundant Saccharomyces cerevisiae 14-3-3 isoforms. In this work we provide evidence that defective 14-3-3 functions not only impair the ability of yeast cells to sustain DNA replication in the presence of sublethal concentrations of methyl methanesulfonate (MMS) or hydroxyurea (HU) but also cause S-phase checkpoint hyperactivation. Inactivation of the catalytic subunit of the histone acetyltransferase NuA4 or of its interactor Yng2, besides leading to S-phase defects and persistent checkpoint activation in the presence of genotoxic agents, is lethal for bmh mutants. Conversely, the lack of the histone deacetylase subunit Rpd3 or Sin3 partially suppresses the hypersensitivity to HU of bmh mutants and restores their ability to complete DNA replication in the presence of MMS or HU. These data strongly suggest that reduced acetyltransferase functionality might account for the S-phase defects of bmh mutants in the presence of genotoxic agents. Consistent with a role of 14-3-3 proteins in acetyltransferase and deacetylase regulation, we find that acetylation of H3 and H4 histone tails is reduced in temperature-sensitive bmh mutants shifted to the restrictive temperature. Moreover, Bmh proteins physically interact, directly or indirectly, with the Esa1 acetyltransferase throughout the cell cycle and with the Rpd3 deacetylase specifically during unperturbed S phase and after HU treatment. Taken together, our results highlight a novel role for 14-3-3 proteins in the regulation of histone acetyltransferase and deacetylase functions in the response to replicative stress.
authors.affiliation: Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, 20126 Milan, Italy.
authors.forename: Francisca
authors.initials: F
authors.lastname: Lottersberger
authors.forename: Andrea
authors.initials: A
authors.lastname: Panza
authors.forename: Giovanna
authors.initials: G
authors.lastname: Lucchini
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Longhese
mesh_terms: D048948:14-3-3 Proteins / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism; D064447:Checkpoint Kinase 2; D004261:DNA Replication; D004271:DNA, Fungal / Q000235:genetics*; D004789:Enzyme Activation; D016681:Genome, Fungal / Q000235:genetics; D051548:Histone Acetyltransferases / Q000235:genetics / Q000378:metabolism*; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins; D008741:Methyl Methanesulfonate / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D016196:S Phase; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D048948:14-3-3 Proteins; D018797:Cell Cycle Proteins; D004271:DNA, Fungal; D047908:Intracellular Signaling Peptides and Proteins; D021122:Protein Subunits; D012097:Repressor Proteins; C071731:SIN3 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D008741:Methyl Methanesulfonate; C496551:Esa1 protein, S cerevisiae; D051548:Histone Acetyltransferases; C504740:NuA4 protein, S cerevisiae; D064447:Checkpoint Kinase 2; C088937:MEC1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; C067022:RAD53 protein, S cerevisiae; C071665:RPD3 protein, S cerevisiae; D006655:Histone Deacetylases