a–j, The morpholinos shown in were used in Fig. 4 and Extended Data Figs 6a–j,8a–f. k–t, The morpholinos shown were used in Extended Data Figs 6k–s, 8g–j. Transverse sections from AxMLP-specific morpholino 1 (a–e) or control morpholino (f–j) electroporated tail. b, The spinal cord (SC) boxed in a. c, The higher-magnification images of the spinal cord boxed in b. AxMLP expression was detected in morpholino-negative cells (red asterisks), whereas it was reduced in morpholino-positive cells (yellow asterisks). d, The epidermis boxed in a. e, AxMLP expression was unaffected in morpholino-negative cells (red asterisks), whereas it was reduced in morpholino-positive cells (yellow arrowheads). In the control morpholino-electroporated tail (f) there was no morpholino-specific knockdown phenotype in either spinal cord (g, h) or epidermis (i, j). The same experiments were performed with AxMLP-specific morpholino 2 (k–o) and the corresponding five-mismatch control morpholino (p–t). k–t, The data sets were the same as a–j. Scale bars, 200 μm (a, f, k, p); 50 μm (b–e, g–j, l–o, q–t).