Fig. 1.

Tat exhibits RSS activity in plant cells that is not attributable to inhibited processing of long dsRNA. (A) N. benthamiana culture cells protoplasts were transfected with GFP reporter plasmid, long GFP-specific dsRNA and the empty vector (Ve) (1) or indicated RSS expression plasmid (2, 3, 4) and monitored for GFP activity 3 days post electroporation. P19, Tat, and HC-Pro restored GFP expression. (B) Quantitative analysis of bulk cultures is summarized from 5 replicate experiments. Expression of indicated RSS increased the GFP fluorescence compared to empty vector control. (C) Northern blot analysis with probe complementary to the antisense strand of gfp effector RNA. HC, P19, and Tat do not induce accumulation of effector RNA. CP induced accumulation of effector RNA. Lower panel is the gel stained with ethidium bromide.