title: Nucleosome recognition and spacing by chromatin remodelling factor ISW1a.
abstract: Nucleosomes are actively positioned along DNA by ATP-dependent, chromatin remodelling factors. A structural model for the ISW1a chromatin remodelling factor from Saccharomyces cerevisiae in complex with a dinucleosome substrate was constructed from the X-ray structures of ISW1a (ΔATPase) with and without DNA bound, two different cryo-EM (cryo-electron microscopy) structures of ISW1a (ΔATPase) bound to a nucleosome, and site-directed photo-cross-linking analyses in solution. The X-ray structure of ISW1a (ΔATPase) with DNA bound suggests that DNA sequence may be involved in nucleosome recognition and thereby specificity of promoter interaction. The model suggests how the highly ordered nucleosome arrays observed by mapping nucleosomes in genes and their promoter regions could be generated by a chromatin remodelling factor.
authors.affiliation: ETH Zürich, Institute of Molecular Biology and Biophysics, Schafmattstrasse 20, CH-8093 Zürich, Switzerland. richmond@mol.biol.ethz.ch
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Richmond
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D042002:Chromatin Assembly and Disassembly; D004268:DNA-Binding Proteins / Q000378:metabolism*; D008954:Models, Biological; D009707:Nucleosomes / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D009707:Nucleosomes; D029701:Saccharomyces cerevisiae Proteins; D000251:Adenosine Triphosphatases; C470546:ISW1 protein, S cerevisiae