Abstract
The topographical locations on the simian virus 40 (SV40) genome of the templates for virus-specific RNA species present late in the lytic infection were determined by RNA-DNA hybridization experiments with the Hind restriction enzyme fragments. Two classes of late virus-specific cytoplasmic mRNA's can be separated on the basis of either sedimentation properties in neutral sucrose or electrophoretic mobility in polyacrylamide gels. In the 16S class, two species of RNA were identified by hybridization experiments. One of these species was complementary to sequences of the early template on the minus (E) strand (0.175 to 0.655 map units), and the other more abundant species was complementary to sequences present in the late template on the plus (L) strand (0.655 to 0.175 map units). In addition two species were detected in the 16S class of late cytoplasmic virus-specific mRNA. One of these species was the major late RNA detected and consisted of a polyadenylated transcript complementary to the plus (L) DNA strands of Hind fragments K, F, J, and G (0.945 to 0.175 map units). This species appears to specify the major capsid protein (VP1). A less abundant nonpolyadenylated 16S RNA species complementary to the plus (L) strands of Hind fragments C, D, and E (0.655 to 0.945 map units) may result from post-transcriptional processing or nonspecific degradation of the 19S viral RNA complementary to the plus (L) strand.