Fig. 6

Fig. 6

Frictional Coupling of Retrograde Cortical Flows Drives Stable-Bleb Migration

(A and D) TIRFM images of (A) Myl12.1-eGFP and (D) Lifeact-GFP localization in motile stable-bleb cells. White dashed line marks the cell-to-substrate contact area. Scale bars represent 10 µm.

(B and E) Kymograph data along the direction of movement indicated by yellow lines in (A) and (D). Green dashed lines outline cell front and rear advancement. White dashed line highlights the rearward flow of a representative fluorescent patch.

(C and F) Retrograde cortical flow velocity data in single stable-bleb cells obtained from kymograph data in (B) and (E) with v_Cell = 24.1 µm/min (C) and v_Cell = 18.2 µm/min (F).

(G and H) Average (black) and single cell local flow velocity data (red) of migrating stable-bleb cells (H) (n = 15) with average cell speed v_Cell = 19.2 ± 2.4 µm/min and of non-motile stable-bleb cells (G) (n = 30) cultured in confinement under agarose on a non-adhesive PEG-coated substrate (v_Cell = 0). Shaded areas denote regions with zero (v = 0, light gray) or anterograde (v < 0, dark gray) cortical flow. Cortical flows are shown in the laboratory frame of reference. All cells were cultured in the presence of 30 µM LPA in confinement under agarose on Fibronectin-coated substrates despite data in (G). n, number of cells. Error bars represent mean ± SEM.

See also Figure S4, Movie S5, and Extended Experimental Procedures.