Fig. 2. Effect of cis elements on trans complementation. Rx constructs are schematically represented as in Figure 1. The CC–NBS(D460V) construct is identical to CC–NBS shown in Figure 1 except that residue D460 is mutated to V, indicated by an asterisk. (A) The CC– NBS(D460V) or CC–NBS polypeptides were co-expressed with the Rx derivatives indicated on the left, in conjunction with either 35S-GUS or 35S-CP via agroinfiltration in N.benthamiana leaves. (B) Rx derivatives indicated on the left were agroinfiltrated with CP plus either Rx LRR, ARC–LRR or NBS–LRR. The occurrence of a HR or not (–) is indicated. Similar results were obtained using either the Rx or the 35S promoter. No HR was observed with any combination in the absence of CP. (C) Potato leaves (rx genotype) were agroinfiltrated with pB1-Rx derivatives in conjunction with either 35S-CP or GUS, as indicated. Constructs were infiltrated at a concentration of agrobacterium of OD600 = 0.2 each.