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Updated: Sep 18, 2025
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Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
Published on: March 3, 2016
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Linker Histone H1.5 Contributes to Centromere Integrity in Human Cells
Ankita Saha1, Minh Bui1, Daniël P Melters1
1National Cancer Institute, Centre for Cancer Research, Laboratory Receptor Biology and Gene Expression, Bethesda, Maryland, USA.
Biorxiv : the Preprint Server for Biology
|June 26, 2025
Summary
Histone H1.5 binds centromeric protein A (CENP-A) nucleosomes, impacting centromeric transcription and mitotic integrity. This study reveals a novel role for histone H1 in regulating cell division.
Area of Science:
- Molecular Biology
- Epigenetics
- Cell Biology
Background:
- Mammalian linker histones (H1 variants) modulate chromatin structure and gene expression.
- The precise role of H1 histones at centromeres remains controversial.
- Centromeric chromatin is crucial for chromosome segregation during cell division.
Purpose of the Study:
- To investigate the interaction of H1 histone variants with centromeric chromatin.
- To determine the functional significance of H1.5 at the centromere.
- To elucidate the role of H1 histones in maintaining mitotic integrity.
Main Methods:
- In vitro binding assays using purified proteins.
- Chromatin immunoprecipitation in human cells.
- RNA sequencing to assess centromeric transcription.
- Analysis of mitotic defects and CENP-A loading.
Main Results:
- Histone H1.5 directly interacts with CENP-A nucleosomes in vitro.
- H1.0 and H1.2 also bind CENP-A nucleosomes with varying affinities.
- H1.5 localizes to centromeres in human cells and interacts with CENP-A nucleosomes.
- H1.5 depletion disrupts centromeric transcription, reduces CENP-A loading, and causes mitotic defects.
Conclusions:
- Histone H1.5 plays a critical role in centromeric chromatin regulation.
- H1 histone variants can interact with CENP-A nucleosomes, suggesting broader roles.
- Histone H1 is essential for maintaining mitotic integrity in human cells.
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