Fig. 5. Retinal ganglion cell axonal outgrowth is slower after the depletion of the Xena/XVASP proteins. (A) The percentage of retinal axons, lipofected with control RFP or with FP4-Mito-GFP+RFP, with terminals in the optic nerve head, the brain entry point, the optic chiasm or the optic tract and tectum at stage 39 (left) and with terminals in the optic tract and tectum at stage 42 (right) [mean±s.e.m. from samples of 120 retinal ganglion cells (RGCs)]. ^***P<0.001, FP4-Mito-expressing growth cones compared with control growth cones in the corresponding region. (B) The average rate of elongation, basal rate of extension, frequency and duration of growth cone pauses from the ventral to the dorsal optic tract (VOT-DOT), as well as at the tectum border, are shown (mean±s.e.m. from samples of 15 RGCs). ^*P<0.05, ^***P<0.001; FP4-Mito-expressing growth cones compared with control growth cones in similar portions of the optic tract. °P<0.05, °°P<0.01, °°°P<0.001, compared axons in the optic tract and at the tectum border. OT, optic tract; RGCs, retinal ganglion cells.