title: Scm3 is a centromeric nucleosome assembly factor.
abstract: The Cse4 nucleosome at each budding yeast centromere must be faithfully assembled each cell cycle to specify the site of kinetochore assembly and microtubule attachment for chromosome segregation. Although Scm3 is required for the localization of the centromeric H3 histone variant Cse4 to centromeres, its role in nucleosome assembly has not been tested. We demonstrate that Scm3 is able to mediate the assembly of Cse4 nucleosomes in vitro, but not H3 nucleosomes, as measured by a supercoiling assay. Localization of Cse4 to centromeres and the assembly activity depend on an evolutionarily conserved core motif in Scm3, but localization of the CBF3 subunit Ndc10 to centromeres does not depend on this motif. The centromere targeting domain of Cse4 is sufficient for Scm3 nucleosome assembly activity. Assembly does not depend on centromeric sequence. We propose that Scm3 plays an active role in centromeric nucleosome assembly.
authors.affiliation: Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA.
authors.forename: Manjunatha
authors.initials: M
authors.lastname: Shivaraju
authors.forename: Raymond
authors.initials: R
authors.lastname: Camahort
authors.forename: Mark
authors.initials: M
authors.lastname: Mattingly
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Gerton
mesh_terms: D002453:Cell Cycle / Q000235:genetics / Q000502:physiology; D002503:Centromere / Q000235:genetics / Q000378:metabolism*; D047369:Chromatin Immunoprecipitation; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005434:Flow Cytometry; D006657:Histones / Q000235:genetics / Q000378:metabolism; D047468:Immunoprecipitation; D018386:Kinetochores / Q000378:metabolism; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D009707:Nucleosomes / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C081071:CBF2 protein, S cerevisiae; C092746:CSE4 protein, S cerevisiae; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D006657:Histones; D009707:Nucleosomes; D029701:Saccharomyces cerevisiae Proteins; C521684:Scm3 protein, S cerevisiae