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Distinct differences in chromatin structure at subtelomeric X and Y' elements in budding yeast.

ABSTRACT: In Saccharomyces cerevisiae, all ends of telomeric DNA contain telomeric repeats of (TG(1-3)), 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 nucleosomes, whereas X elements are repressed and devoid of nucleosomes. In contrast to X elements, the Y' elements also lack the classical hallmarks of heterochromatin, such as high Sir3 and Rap1 occupancy as well as low levels of histone H4 lysine 16 acetylation. Our analyses suggest that the presence of X and Y' elements govern chromatin structure and transcription activity at individual chromosome ends.

SUBMITTER: Zhu X

PROVIDER: S-EPMC2709909 | biostudies-literature | 2009

REPOSITORIES: biostudies-literature

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Distinct differences in chromatin structure at subtelomeric X and Y' elements in budding yeast.

Zhu Xuefeng X Gustafsson Claes M CM

PloS one 20090723 7

In Saccharomyces cerevisiae, all ends of telomeric DNA contain telomeric repeats of (TG(1-3)), 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 nucleosomes, whereas X elements are repressed and devoid of nucleosomes. In contrast to X el ...[more]

PMID: 19626119

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

Project description: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

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