We re-examined the generally accepted concept that replication of Rous sarcoma virus (RSV) requires host DNA synthesis. We used terminally differentiated chicken myotubes as the host because chromosomal DNA replication is completely abolished by the natural differentiation process. Southern blot analysis detected unintegrated viral DNA in both the nucleus and cytoplasm of infected myotubes. This indicated that reverse transcription of the infecting viral RNA and transport of the newly synthesized viral DNA into the nucleus proceeded normally in myotubes. However, restriction enzyme digestion of high DNA prepared from infected myotubes produced none of the fragments specific for RSV, indicating that the viral DNA had failed to integrate into the myotube chromosomal DNA. In these infected myotubes, viral RNA was detected by hybridization. Northern blot analysis showed the presence of all three RSV mRNAs (38S, 28S and 21S). The amount of these viral RNAs in infected myotubes was comparable with that found in infected fibroblasts. We conclude that host DNA synthesis is required for RSV integration, but, in contrast to the generally accepted concept, viral DNA integration is not an absolute requirement for transcription of the RSV genome.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error