(F) Growth of motor neurons from E11.5 - E12.5 WT and crmp2-/- spinal cord explants in microfluidic chambers. Excerpts from 14 hour time-lapse imaging are shown. Upon application of Sema3A into distal compartment, WT axons tend to stop or slow down their growth unlike crmp2-/- axons. Purple lines highlight the growth path of individual axons in a distal chamber. Scale bars: 100 μm. 