FIG 1.

Transient expression of intermediate transcription factor orthologs. (A) Recombinant VACV that express T7 RNA Pol and contains the VACV A8 and A23 intermediate transcription factors (A8/A23), only A23 (ΔA8), only A8 (ΔA23), or neither A8 or A23 (ΔA8/ΔA23) were constructed by homologous recombination using GFP and/or DsRed as a reporter. In the scheme shown, for example, A8/A23 virus expresses both A8 and A23, while ΔA8 virus expresses a GFP reporter and A23. (B) Expression of A8 and A23 orthologs. BS-C-1 cells were infected with ΔA8 or ΔA23 virus and transfected with plasmids that encode A8 orthologs with V5 epitope tags or A23 orthologs with HA epitope tags regulated by T7 promoters. Following cell lysis, proteins were resolved on SDS-polyacrylamide gels, transferred to membranes, and detected with anti-V5 and anti-HA antibodies. The poxviruses from which the A8 or A23 orthologs were derived are as follows: lanes 1, VACV; lanes 2, MYXV; lanes 3, CNPV; lanes 4, CRV; lanes 5, SGPV. C represents a control plasmid not expressing a protein. The masses in kilodaltons to the left of each blot indicate the mobilities of marker proteins.