Submitted to: American Society for Virology Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 2/22/2000
Publication Date: 7/26/2000
Citation: Choi, I., Stenger, D.C., Morris, T.J., French, R.C. 2000. A plant virus vector for systemic expression of foreign genes in cereals. American Society For Virology Meeting. (Meeting not published.)
Technical Abstract: NPT II and GUS were placed between the NIb and CP domains of the wheat streak mosaic virus (WSMV) polyprotein. The WSMV NIb-CP junction containing a NIa protease cleavage site was duplicated, permitting excision of foreign proteins. Wheat, barley, oat, and corn supported systemic infection of WSMV-NPT II. Immunoblotting detected NPT II in wheat and ELISA measured NPT II accumulation in all four cereals. The NPT II insert was stable at 18 days p.i. and had little effect on CP accumulation. Histochemical assays detected GUS in systemically infected wheat and barley inoculated with WSMV-GUS. The GUS insert was subject to deletion and CP accumulation was delayed and reduced relative to wild type, particularly when GUS was produced as a fusion protein. GUS activity in oat was restricted to clusters of cells at infection foci 3 days p.i., whereas in corn GUS activity was never observed. These results demonstrate utility of fWSMV as a gene vector for systemic expression in cereals, and further indicate that both host and inserted sequences affect stability and expression of foreign genes.