Flg22-triggered PTI responses in the llg1 mutants. (A) Quantitative real-time RT-PCR analysis of PR genes at the indicated times after 100 nM flg22 treatment. RNA was extracted from 10-d-old seedlings. (B) Quantitative real-time RT-PCR analysis of the induction of early PTI marker genes 3 h after flg22 treatment. Ten-day-old seedlings were treated with 100 nM flg22 or water (control). In A and B, ACTIN2 was used as the internal control. Error bars represent SD of three independent experiments (n = 3). Asterisks represent significant differences (P < 0.05) using Student’s t test. (C) Flg22-induced activation of MAPKs in Col-0, llg1-2, llg1-3, and fls2 plants. Ten-day-old seedlings were treated with 100 nM flg22. Samples were collected at 0, 5, and 15 min and analyzed by immunoblots using anti-p44/42-ERK antibody. Ponceau S staining of Rubisco is shown as a loading control. The experiments were repeated three times with similar results. (D) Root growth inhibition triggered by flg22 in Col-0, llg1-2, llg1-3, and fls2 plants. Seedlings were treated with 0, 25, 50, 75, or 100 nM flg22 for 8 d. Error bars represent SD of three independent experiments (n = 12).