Expression of WRKY25. A. RNA blot analysis of WRKY25 expression in 5-week old wild-type or mutant Arabidopsis. Two fully expanded leaves were infiltrated with 10 mM MgCl2 (mock inoculation) or Psm ES4326 (OD600 = 0.0001 in 10 mM MgCl2) and harvested at the indicated times after inoculation. After separation on a gel and blotting to nylon membrane, the blot was probed with a WRKY25-specific DNA fragment. B. Induced WRKY25 expression in 5-week old wild-type Arabidopsis plants sprayed with H2O, 2 mM SA, 0.1 mM ACC or 0.1 mM methyl JA. Leaves were harvested at the indicated times after treatment and used for preparation of total RNA and RNA blotting. Ethidium bromide stained rRNA was used as a loading control. The experiments were repeated twice with similar results.