FIG. 7.

In vitro transcription of NA-specific RNP complexes and analysis of the transcription products on oligo(dT)-cellulose. In vitro transcription reactions with RNPs isolated from wild-type (WT) A/WSN/33 virus and D2 or D1/2 transfectant virus were performed with globin mRNA as primer (for details see Materials and Methods). One third of the transcription products was directly analyzed (A) on a 3% polyacrylamide gel in 7 M urea. Two-thirds of the transcription products were separated on oligo(dT)-cellulose, and fractions depleted of (B) and enriched in (C) poly(A)-containing molecules were analyzed on the same gel. A longer exposure of the D1/2 products enriched in poly(A)-containing molecules is shown. The positions of the NP- and NA-specific transcription products are indicated.