title: Stress-dependent dynamics of global chromatin remodeling in yeast: dual role for SWI/SNF in the heat shock stress response.
abstract: Although chromatin structure is known to affect transcriptional activity, it is not clear how broadly patterns of changes in histone modifications and nucleosome occupancy affect the dynamic regulation of transcription in response to perturbations. The identity and role of chromatin remodelers that mediate some of these changes are also unclear. Here, we performed temporal genome-wide analyses of gene expression, nucleosome occupancy, and histone H4 acetylation during the response of yeast (Saccharomyces cerevisiae) to different stresses and report several findings. First, a large class of predominantly ribosomal protein genes, whose transcription was repressed during both heat shock and stationary phase, showed strikingly contrasting histone acetylation patterns. Second, the SWI/SNF complex was required for normal activation as well as repression of genes during heat shock, and loss of SWI/SNF delayed chromatin remodeling at the promoters of activated genes. Third, Snf2 was recruited to ribosomal protein genes and Hsf1 target genes, and its occupancy of this large set of genes was altered during heat shock. Our results suggest a broad and direct dual role for SWI/SNF in chromatin remodeling, during heat shock activation as well as repression, at promoters and coding regions.
authors.affiliation: Institute for Cellular and Molecular Biology and Section of Molecular Genetics and Microbiology, University of Texas at Austin, 1 University Station A4800, Austin, TX 78712-0159, USA.
authors.forename: Sushma
authors.initials: S
authors.lastname: Shivaswamy
authors.forename: Vishwanath R
authors.initials: VR
authors.lastname: Iyer
mesh_terms: D000251:Adenosine Triphosphatases; D042002:Chromatin Assembly and Disassembly / Q000235:genetics / Q000502:physiology*; D047369:Chromatin Immunoprecipitation; D004268:DNA-Binding Proteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology; D015966:Gene Expression Regulation, Fungal; D006360:Heat-Shock Proteins / Q000502:physiology; D006657:Histones / Q000378:metabolism; D006358:Hot Temperature; D008957:Models, Genetic; D009707:Nucleosomes / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D011401:Promoter Regions, Genetic / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000172:deficiency / Q000235:genetics / Q000502:physiology; D014158:Transcription, Genetic / Q000502:physiology
chemical_list: D004268:DNA-Binding Proteins; D006360:Heat-Shock Proteins; D006657:Histones; D009707:Nucleosomes; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D000251:Adenosine Triphosphatases; C499333:SNF2 protein, S cerevisiae