FIGURE 1.

Interaction of RIG-I and in vitro transcribed _5′pppdsRNA1 in vivo. Parallel cultures of 2fTGH cells were treated (or not) with 1000 IU/ml of IFNβ for 12 h and then transfected (or not) with 5 μg of unpurified in vitro transcribed RNA1 containing 5′-biotin-UMP. After 4 h of incubation, cytoplasmic extracts (extr.) were prepared, and equal amounts of extracts were incubated with streptavidin beads. After four cycles of washing, the RIG-I remaining on the beads was determined by Western blotting. The amount of RIG-I present in the extract of 50,000 cells is shown (lanes 1, 2, 7, and 8), as well as that “pulled down” from the extract of 250,000 cells (lanes 3–6).