Fig. 6

NCCs Migrate into the Spinal Cord and Phagocytose CNS Debris (A) Images from a time-lapse movie of a Tg(sox10:nls-Eos);Tg(nkx2.2a:nls-mCherry) embryo starting at 20 hpf. Arrows denote a NCC nuclei crossing into the CNS, which is magnified below. Dashed lines indicate the ventral edge of the spinal cord. (B) Quantification of the ratio of CNS-located NCCs per hemi-segment after ablation of 2 floorplate cells (mean ± SD, n = 8/10 fish for control/ablated). (C) Images of a Tg(sox10:nls-Eos);Tg(nkx2.2a:nls-mCherry);Tg(mnx1:mCerulean) embryo at 20 hpf after ablation of 2 nkx2.2a+ floorplate cells. Left: z projection; middle: 90° rotated image; right: schematic view of the rotated image, illustrating the locations of floorplate cells (fp), motor neurons (mn) and NCCs in the CNS (cN) and PNS (pN). (D) Quantification of the ratio of CNS-located NCCs in embryos with radial glial ablation (n = 5 fish) or DMSO-treated controls (n = 6 fish). The data includes NCCs in 3 hemi-segments per fish. (E) Quantification of the number of NCCs entering the CNS per hemi-segment in DMSO and MTZ-treated embryos within a 20-h time window (mean ± SD). (F and G) Quantification of the number of NCCs per hemi-segment (F) and the ratio of proliferating NCCs (G) in DMSO and MTZ-treated embryos between 20 to 40 hpf (mean ± SD). (H) Distribution of the length of time NCCs spent in the CNS (n = 15 cells). (I) Images from a time-lapse movie of a Tg(sox10:Eos);Tg(gfap:NTR-mCherry) embryo. Arrows denote a NCC engulfment vesicle filled with radial glia debris. Dashed lines mark the ventral edge of the spinal cord. Scale bars, 10 μm.