title: Initiation of transcription in permeabilized Novikoff hepatoma cells.
abstract: Novikoff hepatoma cells, grown in monolayer cultures, when permeabilized by treatment with lysolecithin, incorporated 3H-UTP at a high rate for 2 hours at 25 degrees. The incorporation was inhibited by initiation inhibitors such as rifampicin AF/013, heparin and aurintricarboxylic acid. About 75% of RNA polymerase II, and 45% of RNA polymerase I activities were inhibited by rifampicin AF/013. In contrast, transcription in isolated nuclei was not inhibited either by rifampicin AF/013 or heparin. The permeabilized cells apparently retain the mechanisms for reinitiation in vitro and may be a useful model for studies on the effects of proteins on gene transcription.
mesh_terms: D000818:Animals; D002463:Cell Membrane Permeability / Q000187:drug effects; D002467:Cell Nucleus / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D003609:Dactinomycin / Q000494:pharmacology; D006493:Heparin / Q000494:pharmacology; D008114:Liver Neoplasms, Experimental / Q000235:genetics*; D008244:Lysophosphatidylcholines / Q000494:pharmacology; D012318:RNA Polymerase I / Q000378:metabolism*; D012319:RNA Polymerase II / Q000378:metabolism*; D012320:RNA Polymerase III / Q000378:metabolism*; D012334:RNA, Neoplasm / Q000096:biosynthesis; D012293:Rifampin / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D008244:Lysophosphatidylcholines; D012334:RNA, Neoplasm; D003609:Dactinomycin; D006493:Heparin; D012319:RNA Polymerase II; D012321:DNA-Directed RNA Polymerases; D012318:RNA Polymerase I; D012320:RNA Polymerase III; D012293:Rifampin