title: Synthesis of low molecular weight RNA components A, C and D by polymerase II in alpha-amanitin-resistant hamster cells.
abstract: In an attempt to establish which RNA polymerase catalyzes the synthesis of the low molecular weight RNA components A, C and D, Ama 1 cells (mutant Chinese hamster cells) were used in experiments with addition of alpha-amanitin. Ama 1 cells contain an altered RNA polymerase II which is 800 times more resistant towards inhibition by alpha-amanitin than the wild type enzyme. Alpha-amanitin (up to 200 microgram/ml) added to these cells does not affect the synthesis of the low molecular weight RNAs A, C and D. These data together with our previous data showing that alpha-amanitin (0.5 - 5.0 microgram/ml) preferentially inhibits the synthesis of A, C and D in normal cells indicate that RNA polymerase II catalyzes the synthesis of the low molecular weight RNA components A, C and D.
mesh_terms: D000546:Amanitins / Q000494:pharmacology*; D002460:Cell Line; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004351:Drug Resistance; D008970:Molecular Weight; D012313:RNA / Q000096:biosynthesis; D012319:RNA Polymerase II / Q000378:metabolism*
chemical_list: D000546:Amanitins; D012313:RNA; D012319:RNA Polymerase II; D012321:DNA-Directed RNA Polymerases