Figure 6. SARD1 and CBP60g modulate the expression of signalling components of PTI and contribute to flg22-induced resistance to P.s.t. DC3000.

(a,b) Binding of SARD1-HA (a) and CPB60g-HA (b) to the promoter regions of BAK1, BKK1, AGB1, BIK1, MEKK1, MKK4, MPK3 and CPK4 following P.s.m. ES4326 infection as determined by ChIP-PCR. ChIP was performed as described in Fig. 2. Real-time PCR was carried out using gene-specific primers. ChIP results are presented as fold changes by dividing signals from ChIP with the anti-HA antibody by those of the IgG controls, which are set as one. Bars represent means±s.d. (n=3). (c) Induction of BAK1, BKK1, AGB1, BIK1, MEKK1, MKK4, MPK3 and CPK4 expression by P.s.m. ES4326 as determined by real-time RT–PCR. Samples were collected 12 h after inoculation with P.s.m. ES4326 (OD₆₀₀=0.001) or 10 mM MgCl₂ (mock). Expression levels of the genes were normalized with ACTIN1. Bars represent means±s.d. (n=3). (d) flg22-induced resistance to P.s.t DC3000 on the indicated genotypes. Four-week-old plants were infiltrated with 1 μM flg22 or H₂O 1 day before inoculation with P.s.t. DC3000 (OD₆₀₀=0.001). Bacterial growth was determined 3 days post inoculation. Bars represent means±s.d. (n=5). Statistical differences among the samples are labelled with different letters (ANOVA, P<0.001). ANOVA, analysis of variance; c.f.u., colony-forming unit; P.s.t., P. syringae pv tomato.