FIG. 2.

Northern blot analysis of progeny viral RNAs isolated from cucumber protoplasts inoculated with various combinations of viral RNA transcripts. The RNA transcripts used in the inoculations are indicated at the top, and the positions of the genome (gRNA), sg mRNAs (sgRNA1 and sgRNA2), and defective RNAs (DI-82 and DI-83) are shown at the left. Total nucleic acids were isolated from approximately 3 × 10⁵ protoplasts after a 24-h incubation, separated in nondenaturing 1.4% agarose gels, transferred to a nylon membrane, and hybridized with a ³²P-labeled oligonucleotide probe complementary to the 3′-terminal 23 nucleotides of the TBSV genome.