Conservation of the acetylation pattern of histones and the transcriptional activity in Ehrlich ascites tumor cells by sodium butyrate.

Histone deacetylases of Ehrlich ascites tumor cells are active at low temperatures (0-4 degrees C). The so-called hyperacetylated state of histones is the physiological state of histones in intact Ehrlich ascites tumor cells which is conserved by the continuous presence of 10 mM sodium butyrate during the preparation of nuclei and histones. Isolation of histones in the absence of butyrate causes an artificial decrease in histone acetylation. This artificial loss of histone acetylation produces a decrease of the elongation reaction in the RNA synthesis. The initiation of RNA synthesis is not affected.