title: Transcription of T-DNA in octopine and nopaline crown gall tumours is inhibited by low concentrations of alpha-amanitin.
abstract: Highly purified and physiologically active nuclei were isolated from four different octopine and nopaline crown gall lines. These nuclei exhibited a high endogenous RNA synthesizing activity involving all three RNA-polymerases I, II and III. Isolated nuclei were shown by Southern blotting to synthesize T-DNA specific RNA. This synthesis was shown to be sensitive to actinomycin D and therefore to be DNA-dependent. The transcription of the T-DNA was also inhibited for more than 90% by low concentrations of alpha-amanitin (0.7 micrograms/ml) indicating that the T-DNA, although from bacterial origin, is transcribed by the host RNA polymerase II.
mesh_terms: D000546:Amanitins / Q000494:pharmacology*; D001483:Base Sequence; D002471:Cell Transformation, Neoplastic; D004247:DNA / Q000378:metabolism*; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D003609:Dactinomycin / Q000494:pharmacology; D009693:Nucleic Acid Hybridization; D009994:Osmolar Concentration; D010941:Plant Tumors / Q000032:analysis*; D010957:Plasmids; D012313:RNA / Q000096:biosynthesis; D014158:Transcription, Genetic / Q000187:drug effects*
chemical_list: D000546:Amanitins; D003609:Dactinomycin; D012313:RNA; D004247:DNA; D012321:DNA-Directed RNA Polymerases