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Updated: Jan 10, 2026
05:35
Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
Published on: March 3, 2016
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The CENP-A chaperone complex spatially organizes centromeres.
Hindol Gupta1, Julian Haase1, Yicong Wu2
1Laboratory of Biochemistry & Molecular Biology, Center for Cancer Research, National Cancer Institute, NIH; Bethesda, 20892, USA.
Biorxiv : the Preprint Server for Biology
|November 24, 2025
Summary
Before mitosis, the CENP-A chaperone complex builds shell-like structures at centromeres, creating chromatin-poor cavities. This architecture is crucial for cell division and genome stability.
Area of Science:
- Cell Biology
- Epigenetics
- Molecular Biology
Background:
- Centromeres are essential for chromosome segregation during cell division.
- CENP-A nucleosomes and the constitutive centromere-associated network (CCAN) form inner kinetochore structures.
- The organization of these components before mitosis remains largely unknown.
Purpose of the Study:
- To investigate the interphase structure of centromeres.
- To understand the role of the CENP-A chaperone complex in centromere organization.
- To elucidate the mechanism of centromere preparation for mitosis.
Main Methods:
- Immunofluorescence microscopy
- Super-resolution imaging
- Biochemical assays to study protein interactions
Main Results:
- Interphase CENP-A and CCAN form ~200-300 nm shell structures with a central chromatin-poor cavity.
- The interphase-specific CENP-A chaperone complex occupies this cavity.
- Chaperone presence, not CENP-A incorporation, drives shell formation and chromatin clearing.
- The CCAN scaffold CENP-C is radially organized and essential for structure formation.
Conclusions:
- The CENP-A chaperone machinery plays a critical structural role in interphase centromere organization.
- This machinery establishes centromere architecture prior to mitosis.
- This configuration is vital for faithful kinetochore assembly and genome stability.
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