Figure 2. The isolated tombusvirus replicase preparations from N. benthamiana plants expressing dominant negative ESCRT factors show low activity in vitro.

Top panel: Denaturing PAGE of in vitro replicase activity in the membrane-enriched fraction from co-infiltrated leaves expressing p33, p92^pol, DI-72 repRNA, p19 (suppressor of gene silencing) and the shown dominant negative ESCRT factors using the co-purified repRNA template. The lack of replicase activity in the absence of p33 (lane 11) or p92^pol (lane 12) demonstrates that the in vitro replication is tombusvirus specific. Bottom panel: Western blot analysis of p33 and p92^pol levels in the above membrane-enriched fractions was performed with anti-p33 antibody.