title: X-ray structure of the MMTV-A nucleosome core.
abstract: The conformation of DNA bound in nucleosomes depends on the DNA sequence. Questions such as how nucleosomes are positioned and how they potentially bind sequence-dependent nuclear factors require near-atomic resolution structures of the nucleosome core containing different DNA sequences; despite this, only the DNA for two similar α-satellite sequences and a sequence (601) selected in vitro have been visualized bound in the nucleosome core. Here we report the 2.6-Å resolution X-ray structure of a nucleosome core particle containing the DNA sequence of nucleosome A of the 3'-LTR of the mouse mammary tumor virus (147 bp MMTV-A). To our knowledge, this is the first nucleosome core particle structure containing a promoter sequence and crystallized from Mg(2+) ions. It reveals sequence-dependent DNA conformations not seen previously, including kinking into the DNA major groove.
authors.affiliation: Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, 8093 Zurich, Switzerland.
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Frouws
authors.affiliation: Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, 8093 Zurich, Switzerland.
authors.forename: Sylwia C
authors.initials: SC
authors.lastname: Duda
authors.affiliation: Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, 8093 Zurich, Switzerland richmond@mol.biol.ethz.ch.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Richmond
mesh_terms: D001483:Base Sequence; D018360:Crystallography, X-Ray; D004279:DNA, Viral / Q000235:genetics; D008324:Mammary Tumor Virus, Mouse / Q000737:chemistry* / Q000235:genetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020079:Terminal Repeat Sequences; D014771:Virion / Q000737:chemistry*
chemical_list: D004279:DNA, Viral
keywords: DNA; MMTV; X-ray structure; chromatin; nucleosome