Figure 2. WASp and its phosphorylation are not required for directional response to CSF-1.

The role of WASp in directional sensing was examined by monitoring the chemotactic responses of WASp mutant macrophages in a CSF-1 gradient. Representative kymographs from time-lapse images of (A) shControl, (B) shWASp and (C) Y291F cells in response to a micropipette containing CSF-1 are shown (Movies S1, S2, S3). (D) Overlay of the outlines of the membrane protrusions from panels A through C is shown.