The fascin-1/p-Lin-11/Isl-1/Mec-3 kinase (LIMK)1 interaction promotes stabilization of filopodia. (A-D) Images from confocal time-lapse movies of cells expressing mRFP-fascin-1 with (A) green fluorescent protein (GFP), (B) GFP-LIMK1 (B), (C) GFP-LIMK1T508A or (D) GFP-LIMK1D460A. see Additional files 7 to 10 (movies 4 to 7). There were 15 to 25 cells per condition analyzed in 4 independent experiments. and cells from representative movies are shown. (A-D) Boxed 15 × 15 mm regions in the lefthand panels are enlarged in the images from a series of time points in the right panels. See Additional file 3, Figure S3, for single-channel images from (A) and (B). Scale bars, 10 μm. (E) Kymographs of representative filopodia from cells co-expressing GFP or GFP-LIMK1 and mRFP-fascin-1. Displacement of filopodia was measured in accordance with the maximum change in position of filopodial tips over 2 minutes, as indicated by the dotted yellow lines. (F) Quantification of the maximum displacement of filopodia from cells expressing GFP, or wild-type or mutant GFP-LIMK1 and mRFP-fascin-1. Each column represents the mean from five filopodia from at least five cells per condition in four independent experiments; bars indicate SEM. *P < 0.001 versus GFP control.