Fig. 1.
Expression of PRRSV M protein by rTGEV-derived vectors. (A) Schematic structure of the rTGEV cDNA encoding the PRRSV M gene. The numbers and letters inside the rectangles indicate the viral genes. TRS, transcription-regulating sequence. (B) RT-PCR analysis of ten clones from plaque-purified passage 16 rTGEV-S7.1-TRS3a-M virus. Genomic RNA (gRNA) and subgenomic mRNA (mRNA) encoding PRRSV M protein were detected. The arrow indicates the expected size of the corresponding PCR product. Numbers on the left indicate the molecular weight markers (Mw) size in base pairs. (C) Immunofluorescence analysis of ST cells infected with the passage 16 rTGEV-S7.1-TRS3a-M at 8 hpi. A polyclonal antibody specific for TGEV and a secondary antibody staining red were used to identify virus-infected cells. Expression of PRRSV M protein was detected with a monoclonal antibody and a secondary antibody staining green.