Analyzing Histone Modification Using Crosslinked Chromatin Treated With Micrococcal Nuclease

  • Pascal Lefevre
  • Constanze Bonifer
Part of the Methods in Molecular Biology™ book series (MIMB, volume 325)


Epigenetic processes involve alterations in the covalent modification of histones, which are driven by sequence-specific transcription factors recruiting the enzymatic machinery performing these reactions. Such histone modifications alter the charge or biochemical surface of the chromatin fiber and also serve as “docking” sites for transcription factor and chromatin remodelling complexes. Examining histone modification patterns is vital if we want to understand how transcription complexes establish patterns of gene expression. Histone modification can be quite localized and sometimes only involves a few nucleosomes. We therefore established a chromatin immunoprecipitation procedure that uses crosslinked chromatin allowing the isolation of small chromatin fragments while simultaneously minimizing histone movement during chromatin preparation.

Key Words

Chromatin/nucleosomes histone modifications chromatin immunoprecipitation assay ChIP formaldehyde crosslinking real-time PCR micrococcal nuclease 


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Copyright information

© Humana Press Inc. 2006

Authors and Affiliations

  • Pascal Lefevre
    • 1
  • Constanze Bonifer
    • 2
  1. 1.Molecular Medicine UnitUniversity of Leeds, St. James’s University HospitalLeedsUK
  2. 2.Molecular Medicine UnitUniversity of Leeds; St. James’s University HospitalLeedsUK

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