Expression of avian reovirus σC protein in transgenic plants

Avian reovirus (ARV) structural protein, σC encoded by S1 genome segment, is the prime candidate to become a vaccine against ARV infection. Two plant nuclear expression vectors with expression of σC-encoding gene driven by CaMV 35S promoter and rice actin promoter were constructed, respectively. Agrobacterium containing the S1 expression constructs were used to transform alfalfa, and transformants were selected using hygromysin. The integration of S1 transgene in alfalfa chromosome was confirmed by PCR and histochemical GUS staining. Western blot analysis using antiserum against σC was carried out to determine the expression of σC protein in transgenic alfalfa cells. The highest expression levels of σC protein in the cellular extracts of selected p35S-S1 and pAct1-S1 transgenic alfalfa lines were 0.008% and 0.007% of the total soluble protein, respectively. The transgenic alfalfa cells with expression of σC protein pave the way for the development of edible vaccine.