Induction of premature termination of transcription of the mouse β-globin gene by 5,6-dichloro-1-β-D-ribofuranosylbenzimidazole (DRB)

Abstract

Hybridization of pulse-labeled RNA from DRB-treated Friend cells to mouse β-globin cDNA revealed that the appearance of β-globin mRNA in the cytoplasm was inhibited by greater than 87%. To examine the effect of DRB (125 μM) on HnRNA synthesis, nuclear RNA was electrophoresed in methyl mercuric hydroxide gels, transferred to nitrocellulose, and hybridized with β-globin specific probes. Full-length nuclear transcripts, while present in untreated cells, were not detected in DRB-treated cells. Using restriction enzymes, the cloned β-globin gene was divided into fragments proceeding from the 5′ gene region to the 3′ gene region. RNA labeled in vitro by transcription in nuclei isolated from DRB-treated cells hybridized only to the promoter proximal DNA fragment. Transcripts hybridizing to fragments from both the 5′ and 3′ regions of the gene were produced in nuclei from untreated cells. Together these results indicate that DRB causes premature termination of transcription within the β-globin gene. © 1981 IRL Press Limited.