Figure 6.

Periodic appearance of asterisk-shaped actin aggregates closely associated with oscillatory growth in pollen tubes moderately expressing LlLIM1:GFP. A, Serial images from one typical pollen tube bombarded with 3 μg of LlLIM1:GFP-expressing plasmids showed the oscillatory appearance of asterisk-shaped actin aggregates and growth after culture in germination medium for 6 h. Consecutive confocal time-lapse images were recorded at 9-s intervals with the GFP channels; white lines represent the initial length (at 0 s) of the pollen tube. Arrows indicate the subapical localization of asterisk-shaped actin aggregates. In all cases, the central section of pollen tubes lying flat on the cover-slide surface are shown and represent at least three similar serial images collected from at least two independent experiments. B, Diagram of the curve showing the continuing growth rate of the pollen tube obtained from A; asterisks indicate the time points around fast growth peaks when asterisk-shaped actin aggregates appeared. [See online article for color version of this figure.]