Dataset Information

Genome-wide analysis of condensin binding sites in vertebrate genome

ABSTRACT: The condensin complex is well known to be essential for correct packaging and segregation of chromosomes during mitosis and meiosis in all eukaryotes. To date, the genome wide location and the nature of condensin binding sites has remained elusive in vertebrate systems. A detailed knowledge of condensin binding sites is essential to understand the as-yet enigmatic function of this complex and to define its greater role in chromosome architecture. To address this, we have used next generation sequencing to map condensin I in chicken DT40 cells. Unexpectedly, we found condensin I binds predominately to promoter sequences in mitotic cells. We also found a striking enrichment at both centromeres and telomeres, highlighting the importance of the complex in chromosome segregation. Taken together, the results show condensin I is largely absent from heterochromatic regions. These results reveal for the first time the condensin I binding sites in the vertebrate genome, and demonstrate the importance of the complex in genome segregation and suggest a novel function in gene regulation.

ORGANISM(S): Gallus gallus

PROVIDER: GSE45552 | GEO | 2013/10/03

SECONDARY ACCESSION(S): PRJNA195393

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:The essential process of dosage compensation equalizes X-chromosome gene expression between C. elegans XO males and XX hermaphrodites through a dosage compensation complex (DCC) that resembles condensin. The DCC binds to both X chromosomes of hermaphrodites to repress transcription by half. Here we show that post-translational modification by the SUMO conjugation pathway is essential for sex-specific assembly of the DCC onto X. Depletion of the SUMO peptide in vivo severely disrupts binding of particular DCC subunits and causes changes in X-linked gene expression similar to those caused by disrupting genes encoding DCC subunits. Three DCC subunits are themselves SUMOylated, and depletion of SUMO preferentially reduces their binding to X, suggesting that SUMOylation of DCC subunits is essential for robust association with X. DCC SUMOylation is triggered by the signal that initiates DCC assembly onto X. The initial step of assembly--binding of X-targeting factors to recruitment sites on X (rex sites)--is independent of SUMOylation, but robust binding of the complete complex requires SUMOylation. SUMOylated DCC subunits are enriched at rex sites, and SUMOylation enhances interactions between X-targeting factors and condensin subunits that facilitate DCC binding beyond the low level achieved without SUMOylation. DCC subunits also participate in condensin complexes essential for chromosome segregation, but their SUMOylation occurs only in the context of the DCC. Our results reinforce a newly emerging theme in which multiple proteins of a complex are SUMOylated in response to a specific stimulus, leading to accelerated complex formation and enhanced function. ChIP-chip experiments using antibodies against DPY-27, SDC-3, DPY-30, DPY-26, DPY-28 and FLAG-tagged SDC-2 in wild-type and smo-1 RNAi treated mixed embryos, with IGG controls. Also, sequential ChIP-chip experiments: (1) ChIP using FLAG antibodies to determine the genome-wide binding sites for SUMOylated proteins, (2) ChIP using FLAG antibodies followed by re-ChIP of eluted protein-chromatin complexes with DPY-27 antibodies to determine genome-wide binding sites for SUMOylated DPY-27 (referred to as DPY-27 re-ChIP experiments), (3) ChIP using FLAG antibodies followed by re-ChIP of eluted protein-chromatin with IGG antibodies to determine background binding (referred to as IGG re-ChIP experiments, and (4) ChIP using DPY-27 antibodies as a control to assess the efficiency of DPY-27 binding and detection in control vs. FLAG-tagged strains.

Dataset Information

Genome-wide analysis of condensin binding sites in vertebrate genome

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure