VIEW ARTICLE

Molecular Plant Pathology

Expression of Coat Protein Gene from Cucumber Mosaic Virus Strain C in Tobacco: Protection Against Infections by CMV Strains Transmitted Mechanically or by Aphids. Hector D. Quemada, Molecular Biology Unit–7472, The Upjohn Company, Kalamazoo, MI 49007, Present address: Experimental Plant Genetics Unit–9612, The Upjohn Company, Kalamazoo, MI 49001; Dennis Gonsalves(2), and Jerry L. Slightom(3). (2)Department of Plant Pathology, Cornell University, New York State Agricultural Experiment Station, Geneva 14456; (3)Molecular Biology Unit–7472, The Upjohn Company, Kalamazoo, MI 49007. Phytopathology 81:794-802. Accepted for publication 1 February 1991. Copyright 1991 The American Phytopathological Society. DOI: 10.1094/Phyto-81-794.

The coat protein (CP) gene from cucumber mosaic virus (CMV) strain C was engineered for expression in plants and transferred into the genome of tobacco (Nicotiana tabacum ‘Xanthi’).Transfer of the CP gene was confirmed, and plants containing it produced the expected 1,400-nucleotide mRNA and 24-kDa protein products, which were detected by northern and western blots, respectively. Transgenic tobacco plant lines were infected with CMV strains C and Chi of subgroup I and strain WL of subgroup II, transmitted mechanically or by aphids. The effectiveness of the protection varied in different transgenic plant lines, ranging from almost complete protection to none, depending upon the challenge strain. These experiments demonstrate that within a group of transgenic plants expressing the CP gene of CMV strain C (subgroup I), plant lines can be found that show a significant degree of protection when challenged with CMV strains of either subgroup.