Quantitative profiling of histone post-translational modifications by stable isotope labeling.

Methods for accurately quantitating changes in histone post-translational modifications are necessary for developing an understanding of how their dynamic nature influences nuclear events involving access to genomic DNA. This article describes methods for the use of in vivo stable isotope label incorporation for quantitating the levels of modification at specific residues in histone proteins. These methods are applicable to a wide variety of model systems and examples of their use in both mammalian cells and Saccharomyces cerevisiae are presented.