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Updated: Jun 20, 2026
05:35
Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
Published on: March 3, 2016
Double-strand DNA breaks recruit the centromeric histone CENP-A
Samantha G Zeitlin1, Norman M Baker, Brian R Chapados
1Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093, USA. szeitlin@sciencegeeks.org
Summary
Centromere protein A (CENP-A) rapidly targets DNA double-strand breaks, independent of DNA sequence. This recruitment suggests CENP-A may play a role in cellular DNA repair mechanisms.
Area of Science:
- Cell Biology
- Epigenetics
- DNA Repair
Background:
- Centromere protein A (CENP-A) establishes centromere identity epigenetically.
- Its loading mechanism is independent of DNA sequence, but its precise function at DNA damage sites remains unclear.
Purpose of the Study:
- To investigate the recruitment of CENP-A to DNA double-strand breaks (DSBs).
- To determine the molecular requirements for CENP-A recruitment to DSBs.
- To explore a potential role for CENP-A in DNA repair.
Main Methods:
- Induction of DNA double-strand breaks using I-SceI endonuclease and multiphoton absorption.
- Analysis of CENP-A and associated proteins (CENP-N, CENP-T, CENP-U) recruitment to DSBs.
- Assessment of the role of non-homologous end-joining (NHEJ) pathway components and H2AX.
Main Results:
- CENP-A is rapidly recruited to DSBs in human and mouse cells, along with CENP-N, CENP-T, and CENP-U.
- The centromere-targeting domain of CENP-A is sufficient for this recruitment.
- Recruitment is enhanced by active NHEJ but does not require DNA-PKcs, Ligase IV, or H2AX.
- CENP-A expression levels correlate with survival after radiation-induced DNA damage.
Conclusions:
- DSB induction is sufficient to recruit CENP-A to damage sites.
- CENP-A's ability to target DSBs suggests a novel function in DNA repair pathways.
- Further investigation into CENP-A's role in DNA repair is warranted.
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