FIG. 3.

Immunocapture RT-PCR assay for virions. Virion preparations were obtained from protoplasts inoculated with the in vitro transcripts derived from the cDNA of LIYV RNA 1 (p9/55) (lanes 4, 9, 14, and 19) alone or along with pR6 RNA 2 (lanes 3, 8, 13, and 18) or p1-5b RNA 2 (lanes 2, 7, 12, and 17). Greenhouse-maintained wild-type virions (lanes 6, 11, 16, and 21) and virion RNAs (lanes 5, 10, 15, and 20) purified from LIYV-infected plants were included as positive and negative controls, respectively. Immunocaptured samples were subjected to RT-PCR using primers specific to the 5′ region, nucleotide positions 6 to 278 and nucleotide positions 19 to 504 of RNA 2 (lanes 2 to 6) and RNA 1 (lanes 12 to 16), respectively, and primers specific to the 3′ region, nucleotide positions 6235 to 6537 and nucleotide positions 7085 to 7339 of RNA 2 (lanes 7 to 11) and RNA 1 (lanes 17 to 21), respectively. Sizes in base pairs for DNA standards (lanes 1 and 22) are indicated. The asterisk indicates the position of a nonspecifically amplified product present in samples in lanes 17 to 21. vRNA, viral RNA.