title: Regulation of telomere structure and functions by subunits of the INO80 chromatin remodeling complex.
abstract: ATP-dependent chromatin remodeling complexes have been implicated in the regulation of transcription, replication, and more recently DNA double-strand break repair. Here we report that the Ies3p subunit of the Saccharomyces cerevisiae INO80 chromatin remodeling complex interacts with a conserved tetratricopeptide repeat domain of the telomerase protein Est1p. Deletion of IES3 and some other subunits of the complex induced telomere elongation and altered telomere position effect. In telomerase-negative mutants, loss of Ies3p delayed the emergence of recombinational survivors and stimulated the formation of extrachromosomal telomeric circles in survivors. Deletion of IES3 also resulted in heightened levels of telomere-telomere fusions in telomerase-deficient strains. In addition, a delay in survivor formation was observed in an Arp8p-deficient mutant. Because Arp8p is required for the chromatin remodeling activity of the INO80 complex, the complex may promote recombinational telomere maintenance by altering chromatin structure. Consistent with this notion, we observed preferential localization of multiple subunits of the INO80 complex to telomeres. Our results reveal novel functions for a subunit of the telomerase complex and the INO80 chromatin remodeling complex.
authors.affiliation: Department of Microbiology and Immunology, W. R. Hearst Microbiology Research Center, Weill Medical College of Cornell University, New York, NY 10021, USA.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Yu
authors.forename: Olga
authors.initials: O
authors.lastname: Steinberg-Neifach
authors.forename: Alain T
authors.initials: AT
authors.lastname: Dandjinou
authors.forename: Frances
authors.initials: F
authors.lastname: Kang
authors.forename: Ashby J
authors.initials: AJ
authors.lastname: Morrison
authors.forename: Xuetong
authors.initials: X
authors.lastname: Shen
authors.forename: Neal F
authors.initials: NF
authors.lastname: Lue
mesh_terms: D042002:Chromatin Assembly and Disassembly; D008840:Microfilament Proteins / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000378:metabolism; D021381:Protein Transport; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*; D019098:Telomerase / Q000737:chemistry / Q000378:metabolism; D016615:Telomere / Q000378:metabolism*
chemical_list: C521742:ARP8 protein, S cerevisiae; C483404:INO80 complex, S cerevisiae; D008840:Microfilament Proteins; D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins; C099024:EST1 protein, S cerevisiae; D019098:Telomerase