Figure 4.
Sedimentation and microscopy assays for vesicle release. (a) Representative results from a sedimentation fission assay. SUPER templates were incubated in 20 mM HEPES, 150 mM KCl and 1 mM MgCl2 for 30 min in the presence of 1 mM GTP and with increasing amounts of dynamin (Dyn)-1. Vesicle release is dependent on dynamin-1 presence and concentration and requires GTP. (b) Fluorescence micrograph of released vesicles. (c) SUPER templates were dispersed into assay buffer containing an oxygen-scavenging system and 1 mM GTP in individual wells of an eight-well glass slide. After the beads had settled, imaging was started and Dyn-1 was added to the solution with a pipette to a final concentration of 0.5 μM. The figure shows the field of view before (left) and after (right) addition of Dyn-1. See Supplementary Video 3 for the full sequence. Scale bars, 5 μm.