Movie 1. Transport of EGFP-SMN granules within neuronal processes. Cultured chick forebrain neurons were transfected with EGFP-SMN and imaged live using a cooled CCD camera. Shown here is a time lapse that depicts bi-directional movements of EGFP-SMN granules (shown in black). One can see persistent movements of granules in both anterograde and retrograde directions. One small granule (white bar) takes a rapid retrograde trajectory in the primary neurite toward a branch point and then moves in an anterograde direction into a secondary neurite. Large granules often displayed either oscillatory or bi-directional movements over short distances. Note that the GFP signal is inverted and appears black. (see Figure 3A)

Movie 2. Movements of EGFP-SMNDEx7 aggregates within nucleus. Cultured chick forebrain neurons were transfected with the exon-7 deletion mutant (EGFP-SMNDEx7) and imaged live using a cooled CCD camera. Shown here is a time lapse that depicts an exclusive nuclear localization in the form of aggregates. There was no detection of EGFP-SMNDEx7 granules in the perinuclear cytoplasm. (see Figure 6E)

Movie 3. The GAP-43 membrane targeting sequence directs EGFP-SMNDEx7 granules into neuronal processes. Cultured chick forebrain neurons were transfected with mem/EGFP-SMNDEx7 and imaged live using a cooled CCD camera. This time lapse demonstrates bi-directional granule movements characteristic of the full length EGFP-SMN. One granule is observed to take a long distance anterograde trajectory in an axon-like process that was followed by a shorter retrograde trajectory (white bar). (see Figure 8C)

Movie 4. Active transport of mem/EGFP-SMNDEx7 granules from the cell body into the proximal neurite. Cultured chick forebrain neurons were transfected with the exon-7 deletion mutant fused to the GAP43 targeting sequence (mem/EGFP-SMNDEx7) and imaged live using a cooled CCD camera. This time lapse demonstrate the movement of granule (black) from the cytoplasm into the proximal neurite (white bar). (see Figure 8C)