Fig. 7

The necessity of the kinase activities of LecRK-VI.2 and BAK1 in eNADP⁺ signaling and SAR. a Exogenous NADP⁺-induced local expression of PR1, PR2, and PR5 in the wild-type (WT), lecrk-VI.2-2, LecRK-VI.2:LecRK-VI.2-HA, and LecRK-VI.2:lecrk-VI.2(D494N)-HA plants. Leaves of 4-week-old soil-grown plants were infiltrated with 0.4 mm NADP⁺ or H₂O. The infiltrated leaves were collected 20 hr later. Total RNA was extracted and subjected to qPCR analysis. Expression levels were normalized against the constitutively expressed UBQ5. Data represent the mean ± SD of three biological replicates. Asterisks denote significant differences between the induction in the mutant or transgenic plants and that in the wild type (**p < 0.01, ***p < 0.001; two-way ANOVA with Sidak’s test). b Exogenous NADP⁺-induced local resistance in the wild-type, lecrk-VI.2-2, LecRK-VI.2:LecRK-VI.2-HA, and LecRK-VI.2:lecrk-VI.2(D494N)-HA plants. Leaves of 4-week-old soil-grown plants were infiltrated with 0.4 mm NADP⁺ or H₂O. Five hr later, the infiltrated leaves were inoculated with a Psm suspension (OD₆₀₀ = 0.001). Three d later, eight leaves were collected to examine the growth of the pathogen. Data represent the mean ± SD of eight biological replicates. Asterisks denote significant differences between the induction in the mutant or transgenic plants and that in the wild type (***p < 0.001; two-way ANOVA with Sidak’s test). c Biological induction of SAR in the wild-type, lecrk-VI.2-2, LecRK-VI.2:LecRK-VI.2-HA, and LecRK-VI.2:lecrk-VI.2(D494N)-HA plants. Three lower leaves on each 4-week-old soil-grown plant were infiltrated with 10 mm MgCl₂ or a Psm suspension (OD₆₀₀ = 0.002). Two d later, two systemic leaves were challenge-inoculated with Psm (OD₆₀₀ = 0.001). Three d later, eight leaves were collected to examine the growth of the pathogen. Data represent the mean ± SD of eight biological replicates. Asterisks denote significant differences between the induction in the mutant or transgenic plants and that in the wild type (***p < 0.001; two-way ANOVA with Sidak’s test). d Exogenous NADP⁺-induced local expression of PR1, PR2, and PR5 in the wild-type, bak1-5, 35 S:BAK1-GFP, and 35 S:bak1(K317E)-GFP plants. The experiment was conducted as in a. Data represent the mean ± SD of three biological replicates. Asterisks denote significant differences between the induction in the mutant or transgenic plants and that in the wild type (***p < 0.001; two-way ANOVA with Sidak’s test). e Exogenous NADP⁺-induced local resistance in the wild-type, bak1-5, 35 S:BAK1-GFP, and 35 S:bak1(K317E)-GFP plants. The experiment was conducted as in b. Data represent the mean ± SD of eight biological replicates. Asterisks denote significant differences between the induction in the mutant or transgenic plants and that in the wild type (**p < 0.01; two-way ANOVA with Sidak’s test). f Biological induction of SAR in the wild-type, bak1-5, 35 S:BAK1-GFP, and 35 S:bak1(K317E)-GFP plants. The experiment was conducted as in c. Data represent the mean ± SD of eight biological replicates. Asterisks denote significant differences between the induction in the mutant or transgenic plants and that in the wild type (***p < 0.001; two-way ANOVA with Sidak’s test)