A VARIANT OF POLYOMA VIRUS ALTERED IN ITS PROCESSING OF LATE VIRAL RNA

Publisher Summary This chapter describes the variant of polyoma virus altered in its processing of late viral RNA. The 3049 variant of Py virus is altered in a step associated with the processing of its primary late transcript. It is recognized by its unusual phenotype in an indirect immunofluorescent test using antibody directed against capsid antigens. Cells infected with w.t. virus fluoresce only in the nucleus, whereas 3049 infected cells fluoresce in both nucleus and cytoplasm—a phenotype related to overproduction of viral proteins. In all early lytic events and in the amount and timing of viral DNA replication, 3049 and w.t. are the same. It is found that in the nucleus, at late times, the amount of high molecular weight and total nuclear viral RNA is the same. In 3049 infected cells, there is a three- to fivefold increase in the amount of viral capsid proteins and a difference in their relative distribution. The difference in relative distribution of 3049 capsid proteins suggests the possibility of a difference in the relative distribution of 3049 messages.