title: The synthesis of ribosomal 5 S RNA in cultured hamster cells during the inhibition of protein synthesis.
abstract: Ribosomal 5 S RNA synthesis in Chinese hamster V79 cells treated with an inhibitory antibiotic of protein synthesis, cycloheximide, was quantitated by hybridization of RNA preparations with plasmid ColE1-pSC101 DNA carrying Xenopus 5 S DNA. In V79 cells, cycloheximide produced a notable decrease in the production of the higher molecular weight ribosomal RNA (rRNA) fraction, whereas the accumulation of both 5 S RNA and polyadenylate-containing messenger RNA was much less affected. When the cellular protein synthesis was inhibited by over 85% of the control, accumulation of 5 S RNA and of rRNA was respectively 40-50% and about 10% of the control. The size distribution analysis of RNA species revealed that 5 S RNAs obtained from V79 cells after treatment with 0.1 microgram/ml or 2.0 microgram/ml cycloheximide were indistinguishable from control. Inhibition of precursor uptake into 5 S RNA by cycloheximide was apparently phase-specific during the cell cycle and was 44-67% and 78-85% of the control for the S and the M phase, respectively. The responses of RNA polymerase III activities to cycloheximide in isolated nuclei from each phase of the cell cycle correlated very well with those of precursor uptake into 5 S RNA observed in vivo, while total solubilized RNA polymerase activities showed no inhibition by the drug at any phase of the cell cycle. Cytosine arabinoside, a specific inhibitor of DNA synthesis, did not cause any decrease in the cellular level of 5 S RNA.
mesh_terms: D000818:Animals; D002453:Cell Cycle; D002478:Cells, Cultured; D006224:Cricetinae; D003412:Cricetulus; D003513:Cycloheximide / Q000494:pharmacology*; D004247:DNA; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D014176:Protein Biosynthesis; D012335:RNA, Ribosomal / Q000096:biosynthesis*; D014982:Xenopus laevis
chemical_list: D012335:RNA, Ribosomal; D004247:DNA; D003513:Cycloheximide; D012321:DNA-Directed RNA Polymerases