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Ribonucleic acid synthesis in isolated rat liver nuclei under conditions of ribonucleic acid processing and transport.

ABSTRACT: A cell-free system is described which permits a significant and prolonged synthesis of RNA in isolated rat liver nuclei, under conditions previously demonstrated to support normal nuclear processing and transport of both rRNA and mRNA. The system contains cytosol but not (NH4)2SO4 or other non-physiological components. Evidence is presented for cytosol factors which stimulate ribosomal, and to a lesser degree, non-ribosomal RNA synthesis.

SUBMITTER: McNamara DJ

PROVIDER: S-EPMC1165430 | biostudies-other | 1975 May

REPOSITORIES: biostudies-other

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Decreased ribonucleic acid synthesis in isolated rat liver nuclei during starvation.

Project description:1. Isolated nuclei from starved rats showed a lowered incorporation of [(14)C]UMP into RNA. 2. The Mg(2+)-dependent incorporation was decreased by 30% after 1 day of starvation, but incorporation in the presence of Mn(2+) and ammonium sulphate decreased only after longer periods of starvation. 3. RNA synthesis by nuclei in the presence of excess of added RNA polymerase was unchanged after 1 day of starvation and was inhibited by 20% after 4 days. 4. The capacity of nuclei to bind actinomycin D was unchanged after 1 day and was decreased by 20% after 4 days of starvation.

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Characterization of the ribonucleic acid synthesized by isolated rat-liver nuclei.

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