Molecular Pharmacology, Vol 9, 283-296, Copyright © 1973 by the American Society for Pharmacology and Experimental Therapeutics

Fluorinated Pyrimidines

XLII. Effect of 5-Trifluoromethyl-1-2'-deoxyuridine on Transcription of Vaccinia Viral Messenger Ribonucleic Acid

¹ McArdle Laboratory for Cancer Research, University of Wisconsin, Madison, Wisconsin 53706

The effect of 5-trifluoromethyl-2'-dexoyuridine (F₃dThd) on transcription in vaccinia virus-infected HeLa cells was studied. The sedimentation profile of the RNA in the cytoplasmic fraction extracted from HeLa cells infected with vaccinia virus in the presence of the analogue shows that no detectable normal late viral mRNA was produced; only 4 S RNA was detected. Hybridization competition experiments, using purified total viral RNA preparations and the isolated 12 S early and 16-28 S late viral mRNA peaks, show that the viral RNA transcribed late in the presence of the analogue lacks 30% of the sequences found in normal late viral RNA. The 4 S RNA transcribed late in the presence of F₃dThd contains both small mRNA sequences and 4 S RNA sequences that are presumably due to tRNA. The presence of F₃dThd has no effect on the size or sequences of viral RNA transcribed from the parental viral genomes.

Note:
ACKNOWLEDGMENT We gratefully acknowledge the skillful technical assistance of Mrs. Virginia Garcia.