FIGURE 4.

The EAR motif is required for PopP2 stability in planta. (A) Agro-mediated co-expression of the PopP2 variants with RPS4 and RRS1-R in tobacco. PopP2^LAAL triggers a cell death response when co-expressed with RPS4 and RRS1-R independent of SRDX fusion. This experiment was conducted 3 times with similar results. (B) Mutation of the PopP2 EAR motif affects PopP2 protein accumulation after transient expression following agro-infiltration in N. benthamiana. The wild-type level of protein accumulation could be restored by fusion of a functional synthetic EAR motif (SRDX), but not by the mutated version (srdx). Immuno-detection of PopP2 variants C-terminally fused to YFP tag was conducted using anti-GFP antibodies. Ponceau S staining of total protein demonstrates equal loading of the samples.