Fig. 4

Detection of the RFP gene in egg-passaged virus stocks by RT-PCR and gel electrophoresis. Viral RNAs were extracted from the EP4, 6, 8 and 10 stocks (A, B, and C), and rZM10 as control. The RFP gene insert and surrounding sequences in the NDV vector were amplified from viral RNAs by using a PrimeScript™ II 1st Strand cDNA Synthesis Kit (TaKaRa Bio Inc, Japan) and a pair of specific primers. The RT-PCR products were analyzed by electrophoresis on 1% agarose gel and photographed using a Tanon-1600 Imager (Tanon, China). The sizes of the DL2 000 Plus DNA Ladder marker (Zoman Bio, China) are labelled with black arrows on the left side of the gel. The predicated sizes of the RT-PCR products from the rZM10-RFP (1685 bp) and the rZM10 control (778 bp) are labeled with black arrows on the right side of the gel