Fig. 3.

Mutations of MYO6 residues within MYO6+ disrupt filopodia formation. (A) HeLa cells were transfected with GFP-MYO6+ control, or with point mutations at specific sites in the MYO6 motor domain (D179Y, K157R, T405A, and T405E), or tail (R1117A to ablate RRL binding site; W1202L to ablate WWY binding site; ΔPIP₂; A1013G) of MYO6+ as specified in the panels, fixed and stained with 568-phalloidin, and imaged by widefield microscopy. (B) Images in A (MYO6+ wild type or head and tail mutants) were quantified by counting the percentage of transfected (GFP-positive) cells presenting GFP-MYO6+ at the tips of filopodia [data are aggregate of three experiments with at least 50 cells per experiment, errors shown are SEM, P values for two-sample t tests with wild type are R1117A P < 0.001, W1202L P = 0.12 (not significant), ΔPIP₂ P < 0.001, A1013G P = 0.58 (not significant), D179Y P < 0.001, K157R P < 0.001, T405A P = 0.83 (not significant), and T405E P = 0.57 (not significant)]. (Scale bars, 20 µm.)