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Effect of the exotoxin of Bacillus thuringiensis on normal and ecdysone-stimulated ribonucleic acid polymerase activity in intact nuclei from the fat-body of Sarcophaga bullata larvae.

ABSTRACT: A nuclear preparation from the fat-body of Sarcophaga bullata was obtained which incorporates nucleotides at a steady rate. Two activities, differing in their response to alpha-amanitin, are present. The activities are not separated by changes in the concentration of (NH(4))(2)SO(4) as effectively as in mammalian nuclei. The activity resistant to alpha-amanitin is stimulated by ecdysone, and both normal and the ecdysone-stimulated activities are inhibited by the exotoxin. The amanitin-sensitive enzyme is also inhibited by exotoxin, but higher concentrations are required.

SUBMITTER: Beebee TJ

PROVIDER: S-EPMC1165918 | biostudies-other | 1973 Sep

REPOSITORIES: biostudies-other

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Differential inhibition of mammalian ribonucleic acid polymerases by an exotoxin from Bacillus thuringiensis. The direct observation of nucleoplasmic ribonucleic acid polymerase activity in intact nuclei.

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