Fig. 6.

Inhibition of tombusvirus RNA accumulation in plants by overexpression of RBD1+2 dominant negative GAPDH mutant. (A) Expression of yeast or N. benthamiana RBD1+2 was evaluated in N. benthamiana leaves, which were coinfiltrated with Agrobacterium carrying a plasmid to launch CNV replication from the 35S promoter. The control samples were obtained from leaves expressing no proteins (pGD, lanes 9 to 10). Total RNA was extracted from leaves 4 days after agroinfiltration. The accumulation of CNV gRNA in the infiltrated N. benthamiana leaves was measured by Northern blotting (top panel). The rRNA was used as a loading control and is shown in an agarose gel stained with ethidium bromide (second panel). The bottom panel shows the accumulation of the yeast or N. benthamiana RBD1+2 in N. benthamiana leaves. (B) Northern blot analysis of the accumulation of CNV gRNA in the systemically infected N. benthamiana leaves, measured as shown in panel A. (C) Symptoms of CNV-infected or mock-infected N. benthamiana plants expressing different RBD1+2 proteins are shown 11 days after infection. Note that the yellow color of the older leaves are due to the damaging effect of agroinfiltration.