Deletion mutants of adenovirus 2: Isolation and initial characterization of virus carrying mutations near the right end of the viral genome

A series of eight deletion mutants of human adenovirus 2 have been isolated by a procedure which employs temperature-sensitive adenovirus mutants as helper viruses. Seven of these deletions are located in the right end of the viral genome and cover portions of early regions 3 and/or 4. The mutant with the largest deletion (807) has been separated from its helper by CsCl density gradient centrifugation. Measurements of the synthesis of viral DNA and late viral protein in 807-infected cells show that the mutant synthesizes DNA normally, and. that it produces reduced amounts of some, but not all, late proteins. These observations suggest that while the region 82.5-95 on the adenoviral genome contains no gene essential for DNA replication, it does include a gene or site whose function affects the synthesis of late proteins encoded by widely separated regions of the viral genome.