GSE100401 Characterizing the nuclease accessibility of DNA in human cells to map higher order structures of chromatin

Contributors : Uwe Schwartz ; Sarah Diermeier ; Josef Exler ; Rodrigo Maldonado ; Gernot L ängstSeries Type : Genome binding/occupancy profiling by high throughput sequencingOrganism : Homo sapiensPackaging of DNA into chromatin regulates DNA accessibility and consequently all DNA-dependent processes. The nucleosome is the basic packaging unit of DNA forming arrays that are suggested, by biochemical studies, to fold hierarchically into ordered higher-order structures of chromatin. This organization has been recently questioned using microscopy techniques, proposing an irregular structure. To address the principles of chromatin organization, we applied an in situ differential MNase-seq strategy and analyzed in silico the results of complete and partial digestions of human chromatin. We investigated whether different levels of chromatin packaging exist in the cell. We assessed the accessibility of chromatin within distinct domains of kb to Mb genomic regions, performed statistical analyses and computer modelling. We found no difference in MNase accessibility, suggesting no difference in fiber folding between domains of euchromatin and heterochromatin or between other sequence and epigenomic features of chromatin. Thus, our data suggests the absence of differentially organized domains of higher-order structures of chromatin. Moreover, we identified only local structural changes, with individual hyper-accessible nucleosomes surrounding regulatory elements, such as enhancers...
Source: GEO: Gene Expression Omnibus - Category: Genetics & Stem Cells Tags: Genome binding/occupancy profiling by high throughput sequencing Homo sapiens Source Type: research