Fig. 3.

Characterization of NtMPK4-silenced and NtMPK4L-silenced plants. (A) Pictures of 1-month-old transgenic plants after sowing. Bar, 9cm. (B) Relative expression levels of NtMPK4 and NtMPK4L transcripts were measured. Error bars indicate standard deviations determined from three independent biological replicates. Asterisks indicate significant differences analyzed using Student’s t-test compared with the relevant vector control at P<0.05 (*) or P<0.01 (**). (C) Immune complex kinase assay of NtMPK4 and NtMPK4L in wild-type (WT), NtMPK4-IR6 (4-IR6), NtMPK4L-IR6 (4L-IR6), and NtMPK4L-IR8 (4L-IR8) plants. Crude extracts were prepared from leaf discs after wounding for 0 or 10min. Phosphorylation of MBP as a substrate was detected by autoradiography. Three independent experiments were performed in all figures.