Chd1 chromatin remodelers maintain nucleosome organization and repress cryptic transcription

ABSTRACT: Proper chromatin organization is essential for defining transcription units and maintaining genomic integrity in eukaryotes. Mutations affecting the chromatin structure can lead to increased cryptic transcription and genomic instability. In this study we found that deletion of the Schizosaccharomyces pombe Chd1-type chromatin remodelers, hrp1 and hrp3, causes strong, genome-wide accumulation of antisense transcripts, while the amount of coding mRNA transcripts is mostly unaffected. Nucleosome mapping revealed a specific role for Chd1-remodelers in the positioning of nucleosomes in gene coding regions. While the arrangement of nucleosomes in promoter regions was similar to WT, nucleosome organization within coding regions was remarkably irregular in hrp1∆hrp3∆ strain. We extended our analysis to other mutations associated with enhanced cryptic transcription activity, such as set2∆, alp13∆, and FACT complex subunit pob3∆. While nucleosomes were severely depleted in the pob3∆ strain, nucleosome positioning was less affected. In sharp contrast, nucleosome organization in the alp13∆ and set2∆ strains was indistinguishable from WT. These data indicate multiple mechanisms in the repression of cryptic promoter activity in eukaryotic cells. Genome-wide profiling of H3K9/K14 acetylation Genome-wide expression analysis of either Alp13-, Set2-, Hrp3 or Hrp1 and Hrp3-deficient cells Genome-wide expression analysis of either Hrp1, Hrp3, or Hrp1 and Hrp3-deficient cells Nucleosome mapping experiments

ORGANISM(S): Schizosaccharomyces pombe

PROVIDER: GSE40872 | GEO | 2012/09/15

SECONDARY ACCESSION(S): PRJNA175270

REPOSITORIES: GEO