mRNA amplification system by viral replicase in transgenic plants.

ABSTRACT

We have constructed transgenic tobacco plants (M1x2-FCP2IFN plants) expressing viral RNA replication genes of brome mosaic virus (BMV) and BMV RNA3 derivative (FCP2IFN) carrying the human gamma interferon (IFN-gamma) gene. In M1x2-FCP2IFN plants the RNA3 derivative expressed from the integrated cDNA was replicated and subgenomic RNA (i.e. mRNA of IFN-gamma) was produced by BMV replicase. The accumulation level of the mRNA of IFN-gamma was approximately 5-fold higher than that by the cauliflower mosaic virus (CaMV) 35S RNA promoter. In addition IFN-gamma accumulated in M1x2-FCP2IFN plants.