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CENP-A nucleosome clusters form rosette-like structures around HJURP during G1.

ABSTRACT: CENP-A is an essential histone H3 variant that epigenetically marks the centromeric region of chromosomes. Here we show that CENP-A nucleosomes form characteristic clusters during the G1 phase of the cell cycle. 2D and 3D super-resolution microscopy and segmentation analysis reveal that these clusters encompass a globular rosette-like structure, which evolves into a more compact structure in late G1. The rosette-like clusters contain numerous CENP-A molecules and form a large cellular structure of ?250-300?nm diameter with remarkably similar shapes for each centromere. Co-localization analysis shows that HJURP, the CENP-A chaperone, is located in the center of the rosette and serves as a nucleation point. The discovery of an HJURP-mediated CENP-A nucleation in human cells and its structural description provide important insights into the mechanism of CENP-A deposition and the organization of CENP-A chromatin in the centromeric region.

SUBMITTER: Andronov L

PROVIDER: S-EPMC6769019 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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CENP-A nucleosome clusters form rosette-like structures around HJURP during G1.

Andronov Leonid L Ouararhni Khalid K Stoll Isabelle I Klaholz Bruno P BP Hamiche Ali A

Nature communications 20190930 1

CENP-A is an essential histone H3 variant that epigenetically marks the centromeric region of chromosomes. Here we show that CENP-A nucleosomes form characteristic clusters during the G1 phase of the cell cycle. 2D and 3D super-resolution microscopy and segmentation analysis reveal that these clusters encompass a globular rosette-like structure, which evolves into a more compact structure in late G1. The rosette-like clusters contain numerous CENP-A molecules and form a large cellular structure ...[more]

PMID: 31570711

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