Analysis of adeno-associated satellite virus DNA

Abstract

Adeno-associated satellite viruses (ASV) cannot replicate unless host cells are coinfected with competent adenoviruses. During replication both satellite virus DNA and adenovirus DNA are produced and the system is difficult to dissect at the molecular level. We have studied a temperature-sensitive mutant (ts 13) of human adenovirus Type 31, which at the non-permissive temperature (around 40 °C) in the absence of detectable synthesis of adenovirus DNA appears to be able to support satellite virus replication with production of intact virions. No adenovirus was detected by infectivity assay. In cells infected with the ts 13 mutant adenovirus alone and labelled with [ 3H]thymidine shortly after infection, no adenovirus DNA was isolated. In cells coinfected with satellite virus Type 1 and the adenovirus mutant, satellite virus DNA was detected. This DNA was infectious as DNA in test systems using a simian adenovirus (SV 15) helper and immunofluorescence assay techniques. The DNA was a linear, 16-S species, approximately 1.5 μm in length, and double stranded under the extraction conditions used (high salt concentrations). No circular molecules were detected either by electron microscopy or by nitrocellulose chromatography. We do not feel that a circular species is involved in satellite virus replication.