FIG. 2.

Transcriptional activity of BRSV and ORSV P proteins. Recombinant P proteins of BRSV and ORSV were expressed in Escherichia coli and purified as described in Materials and Methods. Transcription reactions (10 μl) were reconstituted with the HRSV N-RNA template, HRSV L protein, HEp-2 cell extract (as a source of actin and CK2), and various amounts (25, 50, 100, and 150 ng) of recombinant wild-type (wt) and mutant P proteins, as indicated. incorp., incorporated.