Figure 4.
ERK-type MAPKs are strongly posttranslationally activated during symptom expression in the compatible interaction. Western-blot analysis of the activation of ERK-type MAPKs. Protein extracts from leaves inoculated with compatible or incompatible fungal isolates were probed with an anti-active ERK antiserum that recognizes the dual phosphorylated motif present in the active form (PTEYP). These data demonstrate that at least two ERK-type MAPKs are activated during a compatible interaction between Avalon and isolate IPO323 (top panel). The relative protein loading (Ponceau S staining of the nitrocellulose membrane) is displayed in each case for the 60-kD region.