EXPRESSION OF THE GREEN FLUORESCENT PROTEIN-ENCODING GENE FROM A TOBACCO MOSAIC VIRUS-BASED VECTOR

A cDNA fragment encompassing the Aequorea victoria green fluorescent p rotein-encoding gene (gfp) was introduced into a genomic cDNA done of tobacco mosaic virus (TMV). Infectious RNA transcripts produced in vit ro were used to inoculate tobacco (Nicotiana benthamiana) leaves, Afte r 1-2 days, bright green fluorescent areas could be visualized upon il lumination with a long-wave ultraviolet (UV) light source, The virus w as capable of infecting and expressing gfp in plant tissues both local ly (in the inoculated leaf) and systemically (throughout the entire pl ant). Continued observation of inoculated plants indicated that system ic infection resulted from a combination of two forms of virus movemen t: a slow, cell-to-cell spread with concomitant virus replication and gfp expression, and a rapid, vascular-mediated form of transport witho ut gfp expression.