Kc_600_mM_Salt_Extracted_Chromatin

modENCODE_submission_2756 This submission comes from a modENCODE project of Steven Henikoff. For full list of modENCODE projects, see http://www.genome.gov/26524648 Project Goal: We applied genome-wide profiling to successive salt-extracted fractions of micrococcal nuclease-treated Drosophila chromatin. Chromatin fractions extracted with 80 mM or 150 mM NaCl after digestion contain predominantly mononucleosomes and represent classical "active" chromatin. Profiles of these low-salt soluble fractions display phased nucleosomes over transcriptionally active genes that are locally depleted of histone H3.3 and correspond closely to profiles of histone H2Av (H2A.Z) and RNA polymerase II. This correspondence suggests that transcription can result in loss of H3.3+H2Av nucleosomes and generate low-salt soluble nucleosomes. Nearly quantitative recovery of chromatin is obtained with 600 mM NaCl; however, the remaining insoluble chromatin is enriched in actively transcribed regions. Salt-insoluble chromatin likely represents oligonucleosomes that are attached to large protein complexes. Both low-salt extracted and insoluble chromatin are rich in sequences that correspond to epigenetic regulatory elements genome-wide. The presence of active chromatin at both extremes of salt solubility suggests that these salt fractions capture bound and For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf EXPERIMENT TYPE: tiling array analysis. BIOLOGICAL SOURCE: Cell Line: Kc167; Tissue: embryo-derived cell-line; Developmental Stage: late embryonic stage; Genotype: se/e; Sex: Female; NUMBER OF REPLICATES: 2; EXPERIMENTAL FACTORS: Cell Line Kc167; biochemical fraction (extract) soluble fraction; sodium chloride concentration (Compound) 600 mM; extraction time (sampling_time_point) 1 to 2 hours