Recombinant negative-strand viral RNA templates are described which may
be used with purified RNA-directed RNA polymerase complex to express heterologous
gene products in appropriate host cells and/or to rescue the heterologous gene
in virus particles. The RNA templates are prepared by transcription of appropriate
DNA sequences with a DNA-directed RNA polymerase. The resulting RNA templates are
of the negative-polarity and contain appropriate terminal sequences which enable
the viral RNA-synthesizing apparatus to recognize the template. Bicistronic mRNAs
can be constructed to permit internal initiation of translation of viral sequences
and allow for the expression of foreign protein coding sequences from the regular
terminal initiation site, or vice versa.
