Time lapse images of VD growth cone outgrowth. Series of time-lapse images of VD growth cones in early L2 larvae as they migrate between muscle quadrants. The time in minutes after initiation of the experiment are shown in the lower left corner of each image. The scale bar represents 5 μm. (A) A wild-type VD growth cone displays multiple protrusions. The arrow points to the initiation (at 14 minutes) and retraction (at 18 minutes) of a growth cone filopodium. (B) An arx-7(ok1118M+) growth cone displayed fewer filopodial protrusions and generally less dynamics than wild type. (C) An unc-115(ky275) growth cone displayed few filopodia and generally reduced dynamics. (D) An unc-34(e951) growth cone as it spread along a nerve tract as described in . The growth cone displayed few filopodial protrusions.