Figure 3

VIGS constructs, phenotypes, and suppression of the NbNAG transcripts. A Schematic drawing showing NbNAG structure and two VIGS constructs, TRV:NAG(N1) and TRV:NAG(N2), each containing a different NbNAG cDNA fragment (indicated by bars). The primer set used for RT-PCR is also indicated. B Semiquantitative RT-PCR analysis of NbNAG transcript levels. Three independent VIGS plants were analyzed for TRV:NAG(N1) and TRV:NAG(N2) lines. The actin mRNA level was included as a control. C-F Cell death phenotypes of TRV:NAG VIGS plants. Photographs of the plants were taken at 25 days after infiltration (DAI). G Cell death phenotypes of TRV:NAG VIGS plants at 15 DAI. H and I Root growth of TRV (left) and TRV:NAG lines (right) at 15 (H) and 25 DAI (I). J-M Hand-cut sections of the petiole of the fourth leaf above the infiltrated leaf (J and K) and the stem where the fourth leaf above the infiltrated leaf was attached (L and M) from TRV (J and L) and TRV:NAG lines (K and M) at 15 DAI. Brown-colored dead cells in the vasculature are indicated by the arrows. Scale bars: 200 μm. N and O The stem sections shown in (L and M) were observed under fluorescence microscopy to detect autofluorescent secondary metabolites in TRV (N) and TRV:NAG lines (O). The arrow indicates the autofluorescence around the stem vasculature that undergoes cell death.