Figure 1.
Enhanced resistance and PTI responses in plants overexpressing BSK5.
(A) Western blot analysis of BSK5-HA in total protein extracts of five BSK5 overexpression lines (OE1-OE5) performed with anti-HA antibodies (α:HA). Ponceau S staining of Rubisco is shown as a loading control. (B) Leaves of wild-type, and OE1-OE5 plants were inoculated by infiltration with a suspension of Pst (1x105 CFU/mL). Bacterial growth was measured at 0 and 4 dpi. Data are means ± SE of three biological replicates each including five plants. (C) Leaves of wild-type and OE1-OE5 plants were droplet-inoculated with a suspension of B. cinerea spores (5 x 105 conidia/mL). The size of disease lesions was measured at 3 dpi. Data are means ± SE of three biological replicates each including five plants. (D) ROS production. Leaf disks from plants of the indicated genotypes were treated with flg22 (100 nM), elf18 (100 nM), pep1 (1 μM) or water, and incubated with luminol and horseradish peroxidase. Luminescence was measured as relative luminescence unit for 26 min after treatment every 2 min. Data are means ± SE of three biological repeats each including ten samples. (E) Callose deposition. Leaves were treated with 1 μM flg22, elf18 and pep1 or water, and samples were collected 16 h later. Callose deposits were visualized by fluorescence microscopy and counted. Data are means ± SE of four biological replicates each with five leaves. (F) PR1 mRNA expression. Leaves were sprayed with 100 nM flg22, elf18 and pep1 or water. After 12 h, PR1 mRNA levels were measured by RT-qPCR analysis relative to wild-type mock-inoculated plants. ACTIN2 was used as normalizer. Data are means ± SE of three biological repeats. In B-F, asterisks indicate a significant difference (Student’s t test, P value < .05) compared to wild-type plants.