Figure 6.

 Sodium butyrate and trichostatin A alter histone isoform profiles in B. napus. Core histones from purified HeLa chromatin (lane 1; generously provided by Dr. Jerry Workman, The Pennsylvania State University, University Park) and partially purified histones from control (lane 2), butyrate (lane 3) and trichostatin A-treated (lane 4) plants were subjected to electrophoresis on triton–acid–urea gels to resolve histone isoforms. Proteins were then blotted to nitrocellulose and probed with antibodies raised against hyperacetylated histone H3 of Tetrahymena (kindly provided by Dr. David Allis). HeLa and plant H3 both cross-react with the antibody (lanes 1,2) and are located at gel positions expected based on previous studies (Waterborg et al. 1987; Waterborg 1992). Additional isoforms appear as a result of sodium butyrate and trichostatin A treatment (lanes 3,4). (b/t) Isoforms common to both treatments are denoted; (t) isoforms unique to trichostatin treatment are denoted. An asterisk denotes the only isoform present in control and chemically treated plants.