Gene Expression and Silencing Studies in Phytophthora infestans Reveal Infection-Specific Nutrient Transporters and a Role for the Nitrate Reductase Pathway in Plant Pathogenesis
Fig 2
Expression of infection stage markers during plant colonization by P. infestans.
A. mCherry-expressing transformant of P. infestans 1306 in tomato leaf at 3 dpi, showing hyphae ramifying through intercellular spaces. Selected haustoria are indicated (h), and the dark spaces between red-colored P. infestans hyphae are the plant cells. Haustoria were also observed in tubers and plant material colonized by wild-type P. infestans 1306, which was used for the RNA analysis, but are harder to visualize in a photograph. B. Levels of Avr3a (PITG_14371), Hmp1 (PITG_00375), Centrin (PITG_02616), and Npp1 (PITG_16866) mRNA in tomato leaves and potato tuber slices from Experiment One. Infections were made by dipping whole plants or tuber slices in a suspension of zoospores from P. infestans isolate 1306, and RNA was extracted after 3 or 6 dpi. Bars represent ranges from biological replicates. The right panel indicates the percentage of RNA reads that mapped to P. infestans in the leaves (solid circles) and tubers (open circles). C. Same as panel B, except showing data from Experiment Two.