Visualization of the Adenovirus DNA Terminal Protein, Its Gene, and Messenger RNA

Studies using biochemical and electron microscopical RNA:DNA heteroduplex methods have shown that the transcription patterns of the human adenoviruses are extremely complicated. Almost all early and late mRNAs are spliced. Each transcriptional unit produces a family of RNAs that share common 5' and 3' ends but have alternative splicing. Most of the genome is expressed as relatively abundant mRNAs, except for the region between coordinates 16 and 27. This segment encodes the RNA leader components for the late rightward-transcribed (r-strand) RNAs. However, DNA-negative temperature-sensitive mutations have been mapped to this interval. Recently, experiments by several laboratories using different techniques have elucidated how these mutations might affect DNA replication.A protein of 55,000 daltons (55KD) M is covalently joined to each 5' terminus of adenovirus DNA isolated from virions. The ends of replicating DNA in infected cells are also bound to proteins. The linkage is via a phosphodiester bond between serine and the terminal deoxy-cytidine.