Disturbing the linkage between shootin1 and actin filament retrograde flow by NES-ΔN-shootin1 weakens the actin flow–L1 linkage. (A and B) DIC micrographs showing retrograde movement of L1-Fc–coated beads on axonal growth cones (two days in vitro) overexpressing myc-GST (A, left) or myc-NES-ΔN-shootin1 (B, left), and a time series of the indicated areas at 30-s intervals (A and B, right). (C) The percentage of beads coated with L1-Fc that showed retrograde flow on growth cones expressing myc-GST (n = 41) or myc-NES-ΔN-shootin1 (n = 41), mean velocity of moving beads as means ± SEM (**, P < 0.02), and the percentage of moving beads with indicated velocities. (D) A fluorescent speckle image of EGFP-NES-ΔN-shootin1 in an axonal growth cone (left) and a time series of the indicated area at 5-s intervals (right). Arrowheads indicate a speckle of EGFP-NES-ΔN-shootin1 moving retrogradely. Bars, 5 μm.