Succinylation of histone amino groups facilitates transcription of nucleosomal cores.

Treatment of nucleosomal cores with succinic anhydride, which modifies preferentially the amino-terminal domains of core histones, takes place without dissociation of the particles. Low levels of modification, which cause small structural effects, are accompanied by substantial increases in the efficiency of the nucleosomal cores as in vitro transcription templates for RNA polymerase II. The transcriptional properties of the succinylated nucleosomal cores are similar to those of the acetylated particles (Piñeiro et al., (1991) Biochem. Biophys. Res. Commun. 177, 370-376), indicating that no specific blocking by acetyl residues is required to facilitate in vitro transcription. Moreover, to obtain a certain level of stimulation, a smaller number of groups has to be modified by succinic than by acetic anhydride.