Viral infection of <i>drb4</i> and DRB4 OE line.

<p>(<b>A</b>) Pictures from infected plants with the TRV-PDS virus, 14 days post-infection (dpi). Scale bar: 1 cm. (<b>B</b>) Northern blot analysis of TRV-PDS viral RNA or viral-derived siRNA accumulation in Col-0, <i>drb4</i> and DRB4 OE-27 line using a PDS specific probe. TAS1 tasiRNA accumulation was detected using a siRNA255 probe. miR159 accumulation was used here as a loading control. Values are normalized to miR159 and are expressed as a ratio relative to the wild-type Col-0, which was arbitrarily set to 1.