Fig. 3

Floorplate PCP is neither required nor sufficient for FBMN migration but can support the migration of WT FBMNs.

Confocal images showing dorsal views of 48 hpf hindbrains with anterior to the top. (A,B) Tg(shh:Gal4)-driven expression of Tg(UAS:Xdd1-GFP) (A) and Tg(UAS:Fzd3aΔC-GFP) (B) does not disrupt FBMN (magenta) migration. N = 13 Xdd1-GFP expressing embryos and 26 Fzd3aΔC-GFP expressing embryos. (C,D) Tg(shh:Gal4)-driven floorplate expression of GFP-Vangl2 (blue) in the floorplate of a wild type sibling does not disrupt FBMN migration (magenta) (C) and does not rescue migration in a vangl2 mutant (D). N = 24 vangl2 mutants with GFP-Vangl2 expression in the r4 floorplate, 14 with 5 or more expressing floorplate cells in r4. (C',D') Boxed regions from panels C and D respectively, showing a single z-plane where GFP-Vangl2 (blue) is expressed broadly in floorplate cells whose membranes are marked with the Zn5 antibody (yellow) [69]. (E,F) Genetic chimeras. Cascade blue-dextran marks all donor-derived cells (blue), Tg(isl1:mRFP) marks host FBMNs (magenta in E) and Tg(isl1:GFP) marks wild type donor-derived FBMNs (green in F). (E) The presence of wild type floorplate cells (blue) in a vangl2 mutant host embryo does not rescue the migration of host FBMNs. N = 16 embryos with extensive contribution of WT cells to the floorplate. (F) The presence of wild type floorplate cells (blue) in a vangl2 mutant can, however, support the migration of co-transplanted wild type donor derived FBMNs (green, arrows). N = 8 embryos with migrated donor-derived FBMNs/22 embryos with donor-derived FBMNs; N = 76 migrated FBMNs/383 total donor-derived FBMNs. (E',F') Single Z-planes of the boxed regions from panels E and F respectively, show that donor-derived cells (blue) are in the Zn-5-positive floorplate (yellow). Scale bars: 50 μm, 5μm in the insets.