Increase in initiation sites for chromatin directed RNA synthesis by acetylation of chromosomal proteins.

Treatment of rat liver chromatin with 0.7 mM acetic anhydride (1) leads to an approximately twofold increase in initiation sites for DNA-dependent RNA polymerase from $\text{E.}\text{coli}$. With reconstituted chromatin, in which only the histone moiety was acetylated, again a twofold increase in initiation sites could be observed, compared to control chromatin which had undergone the dissociation and reassociation procedure, but which had not been exposed to acetic anhydride.