Figure 6

Medial migration of intramedullary sensory neuron-like cells in Six1/4^EGFP/EGFPmice. (A-H) Abnormalities in the Six1/4^EGFP/EGFP dorsal root entry zone (DREZ). (B-D) and (F-H) show close-up of the DREZ (indicated with rectangles) in Six1/4^+/EGFP(A) and Six1/4^EGFP/EGFP(E). ISL1/2 (magenta/green)- and enhanced GFP (EGFP; green)-double positive cells (arrowheads) are located across the basal lamina, which is demarcated by the immunofluorescence signal of laminin (magenta). The position of nuclei is visualized with DAPI (green). (I) Time-lapse imaging of EGFP-positive cells on the slice culture of embryonic day 11 Six1/4^EGFP/EGFP lumbar region. Top line shows elapsed time of observation. See also Additional file 5. Dashed lines demarcate the position of the spinal cord (sc). Scale bars: 25 μm (A,E,I) and 10 μm (B-D,F-H).