Fig. 1.

Delivery and production of the type III effector AvrPto by DC3000 is restricted in mkp1 plants in an MPK6-dependent manner. (A) WT, mkp1, and mkp1 mpk6 plants were infected with 1 × 10⁸ cfu/mL DC3000 expressing AvrPto fused to an adenylate cyclase reporter (AvrPto-CyaA). cAMP levels were measured in plants 3 h postinfection (PI). Graphed data are means ± SE of percent cAMP relative to cAMP in WT plants. Data shown were pooled from four independent experiments, each with six samples per genotype; n = 24. (B) Serial-dilution plating of bacteria isolated from infected plants 3 h postinfection. Graphed data are means ± SE; n = 6. Each sample comprises three infected plants. (C) qRT-PCR analysis of avrPto transcripts in plants infected with 5 × 10⁸ cfu/mL DC3000 for 4 h. avrPto transcript levels were normalized to the levels of bacterial RpoD and 16S rRNA transcripts detected in each sample. Each sample was RNA extracted from three infected plants. Six samples were analyzed for each genotype with technical replication of each. Graphed data are means ± SE of percent avrPto transcripts relative to mean avrPto transcript levels in infected WT plants; n = 12. Asterisks in A and C denote significant differences based on Student's t-test: *P < 0.05, **P < 0.01.