Fig. 1.

Infection by a range of viruses inhibited JA-mediated gene expression. N. benthamiana plants systemically infected with either Fny-CMV, LS-CMV, PVX, PVY or TMV were treated with MeJA at 2 weeks post-inoculation. Aerial tissue from three plants per treatment group was harvested immediately prior to treatment (0 h) and at 6 and 24 h following treatment. RNA was extracted from pooled tissue samples and reverse transcription coupled to quantitative PCR was performed to measure the transcript abundance of the JA-regulated transcripts AT3G55290 (a), lipoxygenase 2 (LOX2) (b), DEFENSIN 2.2 (DEF2.2) (c) and TRYPSIN PROTEINASE INHIBITOR (TPI) (d). Transcript accumulation levels were compared with those in mock-inoculated (Mock) plants. Significant suppression of MeJA-induced gene expression changes at one or both post-treatment time points are indicated (t-test: *P<0.05, **P<0.01, ***P<0.001). Histogram bars represent RNA samples from three plants (technical replicates). Error bars represent sem.