Movie 4

Rap activation is required for MTOC polarization towards anti-Ig-coated beads. Vector control and RapGAPII-expressing cells A20 cells that had been transfected with GFP-α-tubulin (green) were mixed with 3-μm diameter anti-IgG-coated fluorescent beads (blue). Time-lapse spinning disk confocal microscopy was used to acquire images every 60 s between 1 min and 16 min after adding the beads to the cells. The videos are played back at 5 frames per second (300X real time).

The Rap1–cofilin-1 pathway coordinates actin reorganization and MTOC polarization at the B cell immune synapse

Jia C. Wang, Jeff Y.-J. Lee, Sonja Christian, May Dang-Lawson, Caitlin Pritchard, Spencer A. Freeman, and Michael R. Gold

J Cell Sci 2017. 130:1094-1109; doi: 10.1242/jcs.191858