Dataset Information

Intricate structure of the interphase chromocenter revealed by the analysis of a factor involved in species formation

ABSTRACT: In higher eukaryotes centromeres often coalesce into a large intranuclear domain called the chromocenter. Chromocenters are important for the organization of pericentric heterochromatin and a disturbance of their formation results in an upregulation of repetitive elements and causes defects in chromosome segregation. Mutations in the gene encoding for the centromere associated Drosophila speciation factor HMR show very similar phenotypes suggesting a role of HMR in chromocenter architecture and function. We performed confocal and super resolution microscopy as well as proximity based biotinylation experiments of HMR, centromeric protein dCenpA and heterochromatic protein HP1a to generate a molecular map of HMR, dCenpA and HP1a bound chromatin. Our work reveals an intricate internal structure of the centromeric chromatin region, which suggests a role of HMR in separating heterochromatin from centromeric chromatin.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Drosophila Melanogaster (fruit Fly)

TISSUE(S): Cell Suspension Culture, Early Embryonic Cell, Cell Culture

SUBMITTER: Andreas Schmidt

LAB HEAD: Axel Imhof

PROVIDER: PXD012551 | Pride | 2020-03-23

REPOSITORIES: Pride

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Dataset's files

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			Action	DRS
	20180705_QEX1_NK_HP1a_minmin_rep01_1.raw	Raw
	20180705_QEX1_NK_HP1a_minmin_rep01_2.raw	Raw
	20180705_QEX1_NK_HP1a_minmin_rep02_1.raw	Raw
	20180705_QEX1_NK_HP1a_minmin_rep02_2.raw	Raw
	20180705_QEX1_NK_HP1a_minmin_rep03_1.raw	Raw

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Publications

A multi-layered structure of the interphase chromocenter revealed by proximity-based biotinylation.

Kochanova Natalia Y NY Schauer Tamas T Mathias Grusha Primal GP Lukacs Andrea A Schmidt Andreas A Flatley Andrew A Schepers Aloys A Thomae Andreas W AW Imhof Axel A

Nucleic acids research 20200501 8

During interphase centromeres often coalesce into a small number of chromocenters, which can be visualized as distinct, DAPI dense nuclear domains. Intact chromocenters play a major role in maintaining genome stability as they stabilize the transcriptionally silent state of repetitive DNA while ensuring centromere function. Despite its biological importance, relatively little is known about the molecular composition of the chromocenter or the processes that mediate chromocenter formation and mai ...[more]

PMID: 32182352

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