The 50S and 35S RNAs from Newcastle Disease Virus-Infected Cells

Abstract
Electrophoretic analyses of the 50S and 35S Newcastle disease virus-specific RNA from infected [chick embryo] cells before and after heat denaturation make it possible to demonstrate that these regions each contain single-stranded RNA with corresponding S values and partially base-paired structures. The partially base-paired structures which sediment at 50S (40-60S) have a distribution in gels similar to that of the in vitro transcriptive intermediates, and they remain when 50S RNA synthesis (replication) is blocked by cycloheximide. The partially base-paired 35S RNA is more homogeneous and is neither labeled in the in vitro transcription reaction nor when infected cells are treated with cycloheximide. These base-paired structures may be involved in transcription and replication, respectively.