Fig. 1: Erratic migration: a characteristic migration mode of astrocyte progenitors.

a Observations of erratic migration (magenta) and radial migration (blue). VZ derived cells were labeled by in utero electroporation as indicated. The slice at the beginning of observation is shown in left. The erratically migrating cell divided at 15.3 h (h) and continued erratic migration (arrowheads). See also Supplementary Movie 1. b Trajectories of erratic (left) and radial migration (right). The arrows indicate the direction of movement. The horizontal bars represent the border between the CP and the IZ (M, medial; L, lateral). c The migration speeds during each frame interval. Erratic migration is faster than radial migration (Welch t-test, 932 and 961frames of erratic (11 cells) and radial migration (10 cells) in 4 slices, P < 0.0001). d Strategy to investigate the final fate of erratically migrating cells in vitro. e Marker staining of radial and erratic migration cells (arrows) after the cultivation. Radial and erratically migration cells differentiated into TuJ1⁺ neurons (7 among 7 clones), and GFAP⁺ astrocytes (15 among 17 clones). Samples were pooled from three independent experiments. f Method for differentially labeling of neurons (EGFP, green) and astrocyte progenitors (turboRFP, magenta). g Trajectories of GFP- and turboRFP-expressing cells during 25 h of observation. Erratic migration could be found only for the turboRFP-labeled population. See also Supplementary Movie 2. h Distances and directions related to the radial axis (0 degree is the direction from the VZ to CP) achieved by GFP- and turboRFP-expressing cells within the observation period (24.5 h). The distances and directions are plotted in polar graphs (left), and the distribution of moved directions are shown in violin and box plots (right). The moving directions of turboRFP-expressing cells were significantly broader compared to the GFP-expressing cells (Two-tailed Mann-Whitney test, 868 turboRFP+ cells vs. 1944 GFP+cells, P < 0.0001). CP cortical plate, IZ intermediate zone, VZ ventricular zone; Scale bars, 100 μm (g), 50 μm (a, b), 20 μm (e). For detailed information of box plots, see “Statistical analysis” section in Methods. Source data are provided as a Source Data file.