Requirement of adenovirus type 12 gene 401 function for initiation of virus DNA synthesis.

The highly oncogenic human adenovirus type 12 temperature sensitive mutant. H12ts401, is unable to maintain the growth characteristics of transformed cells at the non-permissive temperature. In lytic infection, the 401 gene function is required to produce virus DNA. In the present study, virus DNA synthesized in ts401-infected human cells after temperature shift-up was characterized. No apparent suppression of DNA chain elongation or ligation occurs at the non-permissive temperature, but, as shown by density labelling, new initiation of virus DNA replication is inhibited under this condition. The results indicate that the 401 gene function is involved in the initiation of virus DNA synthesis in the lytic cycle.