Two-dimensional gel analysis of histones in acid extracts of nuclei, cells, and tissues.

Two-dimensional gel analysis of histones from extracts of nuclei, cells, and tissues is described. A discontinuous buffer system concentrates the sample was used to increase resolution in both dimensions and also to allow the direct loading of HCl extracts of chromatin, nuclei, cells, and tissues. Stained one-dimensional gels are used as sample gels for the second dimension, cetylltrimethylammonium bromide being used to solubilize the proteins in the dye-protein complex. These methods enable one to purify proteins through acetic acid/urea/Triton, acetic acid/urea, and sodium dodecyl sulfate gels without eluting them from the gels. The method is also compatible with the use of protamine to displace histones from nuclei and nucleosomes separated in chromatin gels.