Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Neurosci Methods. 2006 Sep 30;156(1-2):284-92. Epub 2006 Mar 30.

Chromatin immunoprecipitation in postmortem brain.

Author information

  • 1Brudnick Neuropsychiatric Research Institute, Department of Psychiatry, University of Massachusetts Medical School, Worcester, MA 01604, USA. hsien-sung@umassmed.edu

Abstract

Methylation and other covalent modifications of nucleosome core histones are key regulators of chromatin structure and function, including epigenetic control of gene expression. For the human brain, however, very little is known about the regulation of histone modifications at specific genomic loci. Furthermore, chromatin immunoprecipitation protocols applicable to postmortem tissue are lacking, and the impact of potential confounds such as autolysis time or tissue pH is unknown. We treated cerebral cortex from human postmortem brain and mice by micrococcal nuclease digestion or, alternatively, by formaldehyde-crosslinking and sonication. We show that the bulk of nucleosomal DNA remains attached to histones during the first 30 h after death. Immunoprecipitation with antibodies against methylated histones was at least 10-fold more effective in unfixed, micrococcal nuclease-digested samples, in comparison to extracts prepared by fixation and sonication. Histone methylation differences across various genomic sites were maintained within a wide range of autolysis times and tissue pH. Therefore, immunoprecipitation of micrococcal nuclease-digested tissue extracts is a feasible approach to profile histone methylation at defined genomic loci in postmortem brain.

PMID:
16574239
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk