Fig. 4

Effects of NCI-65828 and terrein on zebrafish spinal neurons. (A) Experimental plan for drug treatment of embryos at 10 hpf prior to specification of primary motor neurons and primary motor axon outgrowth. (B) Experimental plan for drug treatment of embryos at 18 hpf after specification of primary motor neurons but prior to primary motor axon outgrowth. (C) Diagrams of embryos at 27 and 36hpf with regions analysed highlighted (D) Islet1 immunostaining at 27 and 36 hpf in the developing spinal cord of embryos treated from 10 hpf with NCI-65828 or terrein. Increased gaps between islet⁺ nuclei seen (white asterisks). A/P, anterior/posterior. (E) Quantification of motor and Rohon-Beard sensory neurons in the spinal cord at the indicated time-points over the three regions anterior (A) to posterior (P) from 20 embryos (two replicates with 10 embryos each) shows a significant decrease (*p < 0.05) after treatment at 10 hpf. Regions counted and binned as shown by dashed regions in panel C and D.