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Non-canonical DNA structures at eukaryotic centromeres can resolve the CENP-B paradox

ABSTRACT: Epigenetic mechanisms are thought to specify the identity of centromeres, yet the degree to which DNA sequence contributes to centromere determination remains unresolved. For example, the conserved CENP-B protein binds the 17-bp âCENP-B boxâ motif found in Î±-satellite arrays at most human centromeres. Although CENP-B is required for artificial centromere function, it is non-essential and some species lack CENP-B boxes entirely. To address this âCENP-B paradox,â we determined the distribution of CENP-B boxes in primates and directly demonstrated the absence of CENP-B at Old World Monkey centromeres. We found extensive interspecific variation in Î±-satellite arrays including abundance of <10-bp dyad symmetries and of non-B-form DNA structures. We confirmed the presence of non-canonical DNA at human centromeres and neocentromeres and detected similar structures at mouse, chicken and yeast centromeres. To resolve the CENP-B paradox, we propose that CENP-B enhances non-canonical DNA formation, thus providing a general basis for centromere specification.

ORGANISM(S): Chlorocebus aethiops Homo sapiens

PROVIDER: GSE102111 | GEO | 2018/01/28

REPOSITORIES: GEO

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Genome-wide maps of CENP-A nucleosomes in three neocentromere-containing cell lines

Project description:We used native ChIP-seq of CENP-A-containing particles from normal centromeres on alpha-satellite DNA and three naturally-occurring neocentromeres to test the proposed models for the major form of the fundamental repeating unit of centromeric chromatin. We found that the predominant form of the CENP-A particle at the centromere is an octameric nucleosome with loose terminal DNA. Additionally, we found CENP-A nucleosomes are strongly phased on the 171 bp alpha-satellite monomers of normal centromeres, and also display strong positioning and neocentromeres. Comparison of CENP-A and bulk nucleosome DNA lengths and positions in three different human neocentromere-containing cell lines

2013-05-04 | E-GEOD-44724 | biostudies-arrayexpress

Genome-wide maps of CENP-A nucleosomes in three neocentromere-containing cell lines

2013-05-04 | GSE44724 | GEO

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2019-03-20 | GSE111381 | GEO

Hap2-Ino80 mediated transcription facilitates de novo establishment of CENP-A chromatin

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2020-05-27 | PXD016602 | Pride

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2017-07-14 | GSE99589 | GEO

A high-resolution map of inner kinetochore proteins in fission yeast regional centromeres

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2016-08-04 | E-GEOD-85166 | biostudies-arrayexpress

Sequences Associated with Centromere Competency in the Human Genome

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2013-03-29 | E-GEOD-45497 | biostudies-arrayexpress

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2016-08-04 | GSE85166 | GEO

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