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Distinct differences in chromatin structure at telomeric X- and Y-elements in budding yeast.

ABSTRACT: The telomeric repeat sequences (TGTGG) are the same at all chromosome ends, but the number and position of subtelomeric X and Y repeat elements vary. Using chromatin immunoprecipitation and genome-wide analyses, we here demonstrate that the subtelomeric X and Y elements have distinct structural and functional properties. Y elements are transcriptionally active and highly enriched in histones, whereas X elements are repressed and completely devoid of nucleosomes. In contrast to X elements, the Y elements lack the classical hallmarks of heterochromatin, e.g. high Sir3 and Rap1 occupancy as well as low levels of histone 4 lysine 16 acetylation, Our analyses refute the idea that subtelomeric silencing is a general phenomenon and suggest that the presence of X and Y elements govern the chromatin structure and transcription activtiy at individual chromosome ends. Keywords: nucleosome position and Histone 4 lys 16 acetylation Chip on CHIP

ORGANISM(S): Saccharomyces cerevisiae

PROVIDER: GSE13615 | GEO | 2009/07/01

SECONDARY ACCESSION(S): PRJNA110639

REPOSITORIES: GEO

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