Chromatin directed transcription of 5S and tRNA genes.

Abstract Chromatin prepared by gentle methods from mouse myeloma cells retained its ability to synthesize RNA using bound endogenous RNA polymerase (RNA nucleotidyltransferase; nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6). The transcription resembles that observed in vivo in several respects. The low-molecular-weight RNA species 5S RNA and the 4.5S precursor to 4S RNA, are transcribed accurately and transcription is reinitiated continually in vitro. Their synthesis was not inhibited by alpha-amanitin (1 mug/ml) as was found previously for these species in isolated nuclei.