Cloning and expression of human calcitonin genes in transgenic potato plants

Synthetic human calcitonin monomeric (hCT(m)) and tetrameric (hCT(t)) genes were cloned under the control of the 35S cauliflower mosaic virus (CaMV) p romoter linked to the 5'-non-translated leader sequence of tobacco etch vir us (TEV). The resulting constructs were cloned into the binary vector Bin19 and potato minituber discs were transformed using an Agrobacterium strain. Northern dot-blot and RT-PCR were applied for monitoring of transcription. Translation of the hCT(m) and hCT(t) mRNAs was studied by radioimmunoassay and molecular size of the recombinant proteins was determined by SDS-PAGE. The estimated average yield of recombinant hCT in the transgenic potato pl ants was about 0.02% of the total soluble protein.