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Updated: Jun 16, 2026
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Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
Published on: March 3, 2016
CENP-B controls centromere formation depending on the chromatin context.
Teruaki Okada1, Jun-ichirou Ohzeki, Megumi Nakano
1Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan.
Cell
|December 28, 2007
Summary
Centromere assembly requires CENP-B protein. This protein drives new centromere formation on artificial chromosomes but prevents extra centromeres on existing chromosomes by promoting heterochromatin.
Area of Science:
- * Molecular Biology
- * Epigenetics
- * Chromosome Biology
Background:
- * The centromere is crucial for accurate chromosome segregation during cell division.
- * The precise mechanisms governing centromere assembly and stabilization remain incompletely understood.
- * Alpha-satellite DNA and CENP-B protein are known to be involved in centromere formation.
Purpose of the Study:
- * To elucidate the role of CENP-B in de novo centromere assembly on human/mammalian artificial chromosomes (HAC/MAC).
- * To investigate the effect of CENP-B on centromere formation when alpha-satellite DNA is integrated into existing chromosomal sites.
- * To understand the dual function of CENP-B in regulating centromere formation.
Main Methods:
- * Construction and analysis of human/mammalian artificial chromosomes (HAC/MAC) with integrated alpha-satellite DNA.
- * Gene expression studies involving CENP-B in cell lines.
- * Assessment of epigenetic modifications, including histone H3-K9 trimethylation and DNA methylation.
Main Results:
- * De novo centromere assembly on HAC/MAC is dependent on the presence of CENP-B.
- * CENP-B suppresses centromere formation at chromosomal integration sites.
- * CENP-B enhances heterochromatin formation (histone H3-K9 trimethylation and DNA methylation) at integration sites.
Conclusions:
- * CENP-B plays a critical dual role in centromere formation.
- * It facilitates the establishment of new centromeres on DNA lacking them.
- * It prevents the formation of ectopic or excess centromeres on existing chromosomes by promoting heterochromatin formation.
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