Template activity of chromatins isolated from regenerating rat liver.

Abstract

1. The priming (template) activities for RNA synthesis of normal and regenerating rat liver chromatins were investigated using E. coli RNA polymerase [EC 2. 7. 7. 6] and isolated chromatins. A slightly higher template activity was observed in regenerating liver chromatin but no detectable difference in the ratio of histone to DNA compared to that of normal liver chromatin. 2. The template activities of normal and regenerating liver chromatins were compared after removal of different extents of histone with citric acidNaCl. The difference in the template activities of normal and regenerating liver chromatins were still apparent up to a stage of selective removal of lysine-rich histones, but disappeared when most of the histones were removed. 3. Removal of histones with dilute HC1 caused some structural damage of the chromatins resulting in change in the template activity and melting profile. 4. The addition of histones after their removals from chromatins inhibited template activity slightly in contrast to the dramatic increase in template activity seen on removal of histones from chromatins. 5. The regulatory roles of histones in the synthesis of are discussed on the basis of the results.