Analysis of histone modifications by mass spectrometry.

Histone N-termini undergo diverse post-translational modifications that significantly extend the information potential of the genetic code. Moreover, they appear to mark specific chromatin regions, modulating epigenetic control, lineage commitment, and overall function of chromosomes. It is widely accepted that histone modifications affect chromatin function, but the exact mechanisms of how modifications on histone tails and specific combinations of modifications are generated, and how they cross-talk with one another, is still enigmatic. Mass spectrometry is ideal for the analysis of histone modifications and is becoming the gold standard for histone post-translational modification analysis since it allows the quantification of modifications and combinations. This unit describes how high-resolution mass spectrometry can be used to study histone post-translational modifications. (c) 2008 by John Wiley & Sons, Inc.