Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Holocentromeres are dispersed point centromeres localized at transcription factor hotspots

ABSTRACT: The centromere is a defining feature of eukaryotic chromosomes and is essential for the segregation of chromosomes during cell division. Centromeres are universally marked by the histone variant cenH3 and are restricted to specialized chromatin that most commonly localized to a single position along the chromosome. However, the DNA on which centromeric nucleosomes assemble is not conserved and varies greatly in size and composition. It ranges from genetically defined point centromeres that assemble a single cenH3-containing nucleosome to epigenetically defined regional centromeres embedded in megabases of tandemly repeated DNA to holocentromeres that extend along the length of the entire chromosomes. The organization of regional and holocentric centromeres has so far been elusive, as the precise locations of cenH3-containing sequences could not be determined. Our results show that the point centromere is the basic unit of holocentromeres and provide a basis for understanding how centromeric chromatin is maintained. We use high-resolution mapping of cenH3-associated DNA to show that Caenorhabditids elegans holocentromeres are organized as dispersed but discretely localized point centromeres.

ORGANISM(S): Caenorhabditis elegans

SUBMITTER: Jorja Henikoff

PROVIDER: E-GEOD-44412 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Holocentromeres are dispersed point centromeres localized at transcription factor hotspots.

Steiner Florian A FA Henikoff Steven S

eLife 20140101

Centromeres vary greatly in size and sequence composition, ranging from 'point' centromeres with a single cenH3-containing nucleosome to 'regional' centromeres embedded in tandemly repeated sequences to holocentromeres that extend along the length of entire chromosomes. Point centromeres are defined by sequence, whereas regional and holocentromeres are epigenetically defined by the location of cenH3-containing nucleosomes. In this study, we show that Caenorhabditis elegans holocentromeres are or ...[more]

PMID: 24714495

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Dataset Information

Holocentromeres are dispersed point centromeres localized at transcription factor hotspots

Publications

Holocentromeres are dispersed point centromeres localized at transcription factor hotspots.

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