Complementary RNAs in paramyxovirions and paramyxovirus-infected cells.

PARAMYXOVIRIONS contain single-stranded RNAs sedimenting at 50–57S1–3, Newcastle disease virus (NDV) and Sendai virus have been shown to induce infected cells to synthesize single-stranded RNAs which sediment more slowly than virion RNAs and are complementary to them in nucleotide sequences4–6. Interest in these complementary RNAs derives from the possibility that they are templates for viral proteins. For some RNA viruses it is clear that the viral genome is the message7–10; but for paramyxoviruses, the genome may contain little or no genetic information that can be translated directly. Paramyxoviruses do not seem to be unique: vesicular stomatitis virus (VSV) directs the synthesis of RNAs smaller than virion RNA and complementary to it11,12.