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Fig. 3 Lateral-line topographic map and rheotaxis (A and B) Volume-filled skeletons of 6 pLANs morphed onto a reference brain. Each pLAN innervates a different neuromast: L1 (red), L2 (green), L3 (blue), L4 (cyan), L5 (magenta) and Ter (yellow). (A) Side view and (B) top view. The central projections crossed one another along the length of the hindbrain. (C) Scheme of a double injection of a larval zebrafish with magenta and red dextrans, in HGn39D (green). Magenta dextran is injected into the L2 neuromast to label only L2_pLANs. The red dextran is injected into the terminal neuromasts to label only Ter_pLANs. (D) Maximal projection of the central projections of pLANs labeled with magenta and red dextrans, showing with corresponding-color arrowheads the central projections of L2_pLANs and Ter_pLANs relative to one another. The somata of the labeled neurons are indicated with color-coded arrowheads. Note that somatotopy is not precise along the LCL. (E) Scheme of the projections shown and color-coded in (D). (F and G) Central projections of a red- and a magenta-labeled axon within the background of the HGn39D transgenic line that labels the LCL with EGFP (green) (F). Color-coded arrowheads indicate the relative position of each axonal projection along the LCL (G). (H and I) Same specimen after the severing and regeneration of the peripheral axons, revealing that central axons do not change relative position along the somatotopic axis despite peripheral rewiring (I). (J) Orientation of intact and manipulated specimens at 6dpf under no flow (left hand-side, or under laminar water flow at 6mm/s (right hand-side). Scale bars are 50 μm. See also Figure S3 and Videos S2 and S3.