Figure 3

Myosin ii and F-actin dynamics motor activity are required for basal motility of Golgi apparatus. Golgi were imaged in non-migrating CGNs for 1 hour in control (untreated), jasplakinolide-treated, and blebbistatin-treated neurons; average Golgi velocity was measured before and at various time points after addition of cytoskeletal drugs. (A) In control neurons, Golgi velocity remained stable (mean velocity, 0.013 ± 0.006 (SD) μm/sec, n = 53 to 70 Golgi, depending on time point). Below, motility of the Golgi before treatment and at 60 minutes is supported by representative imaging sequences showing the temporal positions of the Golgi (position of the organelle is shown at every 75 seconds in a different color as indicated by the key). Golgi appear to be moving similarly in both images. (B) Golgi velocity diminishes rapidly after treatment with 50 μM blebbistatin. Golgi are motile in the pre-treatment image sequence (mean velocity, 0.013 ± 0.006 μm/sec, n = 52) but almost stationary after 60 minutes of blebbistatin treatment (mean velocity, 0.006 ± 0.005 μm/sec, n = 38, P <0.0001, t-test). (C) Golgi velocity diminishes rapidly after treatment with 5 μM jasplakinolide. The mean velocity was 0.015 ± 0.005 μm/sec (n = 34) before treatment and 0.011 ± 0.005 μm/sec (n = 58, P <0.0001, t-test) after 60 minutes of jasplakinolide treatment. This is also reflected in the images below, comparing pre-treatment movement to 60-minutes post-treatment.