Figure 5.

The vwa1 zebrafish model has impaired spinal motor neuron axon development. Transgenic embryos [Tg(olig2:dsRed), expressing red fluorescent oligodendrocytes and motor neurons axons) were injected with vwa1 CRISPR (knockout) or morpholino (MO, knockdown). Both vwa1 models displayed a significantly shorter motor axons in comparison to control axon growth. Representative embryos full-body lateral view and trunk lateral view for the examined groups at: (A) Spinal cord motor neurons examined at 48 hpf [enlarged images below showing the measurement of axon length from the base of the spinal cord to the end of the motor neuron (white arrow)]; (B) 72 hpf, examined spinal motor neurons (white box) and aberrant developing axons (white arrowheads); and (C) 96 hpf. (D) The vwa1 model resulted in impaired motor neurons axon growth in comparison to control axon growth. Spinal motor neurons axon length was measured for 8–10 axons per embryo starting from axon number 5. Vwa1 Crispants (n = 29) and morphants (n = 26) showed significantly shortened axons compared to controls (n = 22). Zebrafish imaging using Lumar 12 microscope (whole body images, scale bar = 40 mm and axon images, scale bar = 10 mm), t-test was used for statistical analysis. Spinal motor neuron images at a magnification of ×150, scale bar = 10 µm. Statistical analysis was performed with GraphPad Prism 8.0.