Southern blot hybridization analysis of polyoma virus-specific RNA synthesized under the block of virus replication by 5-bromo-2'-deoxyuridine.

Polyoma (Py) virus-specific RNA, synthesized at reduced level in infected cells in the presence of antiviral substance 5-bromo-2'-deoxyuridine was characterized in more detail by Southern blot hybridization analysis. Virus-specific RNA present in 3H-uridine labelled cytoplasmic preparations hybridized to individual viral DNA restriction fragments in a characteristic manner and extent, which was quantitatively assayed. BrdUrd (6.34 micrograms/ml) lowers the hybridization profiles essentially in a proportional manner, which indicates that no new, atypical transcription products are formed in the presence of BrdUrd.