Figure 2.

WIT1 forms aggregates when overexpressed. A, Root cells of a transgenic Arabidopsis line expressing 35S-driven GFP-WIT1. GFP-WIT1 expression was visualized in different transient expression systems (B and C). B, Transiently transformed leaf mesophyll Arabidopsis protoplasts (magenta signal, chlorophyll autofluorescence) and N. benthamiana protoplasts (latter is shown with corresponding bright-field image to mark the position of the nucleus). C, Agroinfiltrated N. benthamiana leaves (with or without p19). D, WIT1 colocalizes with an ER marker. N. benthamiana leaves were coagroinfiltrated with GFP-WIT1 (green) and an mCherry-HDEL ER marker (magenta; Nelson et al., 2007) in the presence of p19. Two magnified insets (a and b) were shown to enable better visualization of colocalization within the ER. A, Aggregation; braces, ER. Bars = 10 μm. The gain settings for images presented in A and C (right) were significantly higher than for other images for better visualization.