Figure 2.

Enhanced HR cell death in transgenic tobacco plants expressing antisense RNA for cAPX. (A) Photograph showing that infiltration of antisense-APX leaves (Right) with a low titer of bacteria (OD₆₀₀ = 0.1) induces HR cell death. In contrast, infiltration of control leaves (Left) with the same titer failed to induce PCD. Infiltration of leaves with a high titer of bacteria (OD₆₀₀ = 1) induced cell death in both plants. Mock infiltration (i.e., OD₆₀₀ = 0) was performed with water. (B) A graph showing enhanced HR cell death in antisense-APX plants infiltrated with different concentrations of the HR-inducing bacteria, P. syringae pv. phaseolicola (NPS3121), compared with control plants infiltrated with the same amount of bacteria. An OD₆₀₀ of 1.0 is the equivalent of 500,000 colony-forming unit (cfu)/ml.