Structure of a large segment of the genome of simian virus 40 that does not encode known proteins

Abstract

The nucleotide sequence of the region of DNA of simian virus 40 extending from 0.595 to 0.790 map unit has been derived. The sequence includes the DNA complementary to the 5' end of early mRNA and to the 5' end of some of the forms of late RNA. Because there are termination codons in all three phases in early and late RNA, there is a sequence of almost 800 nucleotides of simian virus 40 DNA that probably does not code for known viral proteins. The sequence spans the 5' end of the early mRNA at 0.67 map unit and overlaps a species of late RNA whose 5' end is at 0.65 map unit and whose 3' end is at 0.77 map unit. This RNA is retained on oligo(dT)-cellulose columns in high salt concentrations. Analysis of the sequence of late strand RNA suggests that this RNA is not covalently linked to the mRNA that encodes structural proteins. There is another species of late RNA of simian virus 40 whose 5' end is at 0.775 map unit. The nucleotide sequence of this region of simian virus 40 DNA contains several examples of repeated sequences, most of which are located in DNA that does not encode known peptides. These may be analogous to the reiterated sequences that have been described in animal cell DNA.