DEV02382 Supplementary Material

Files in this Data Supplement:

• Supplemental Figure 1 -

  Fig. S1. Ventricle-oriented GIs in the MZ and upper CP three days after DiD injection (E18.5). (A,B) Confocal images of DiD-labelled GFP neurons rostral (A) or caudal (B) to the injection site, observed in a sagittal slice.  A is a merged view of GFP and DiD signals.  Insets show higher magnification views of the DiD-labelled GFP neurons indicated by straight lines in A or B.  Both of them were observed in the CP, extending a leading process toward the ventricle. (C) Similar to A and B, but in a coronal slice. (C1) Low-magnification view of the dorsal cortex. (C2-C4) Higher magnification views of the DiD-labelled GFP neurons indicated by the straight lines in C1. These neurons were located in the CP and extended a leading process toward the ventricle.  Such neurons occasionally extended a long, trailing process that curved in the MZ (C2, arrowheads). (D) Distribution of ventricle-oriented DiD-labelled GFP neurons. Pooled data from five consecutive sagittal (white circles) or nine consecutive coronal (black circles) slices is shown. All ventricle-oriented DiD-labelled GFP neurons were distributed in the MZ or CP, at various distances from the injection site, and at various depths from the pial surface. Asterisks indicate the neurons with a long (more than 1.5 times longer than its leading process) trailing process that reached the MZ.  R, rostral; M, medial; V, ventral. Dotted lines indicate the slice outline. Scale bars: A,B, 100 µm; C1, 200 µm; A,B, insets, 10 µm; C2-C4, 10 µm.

• Supplemental Figure 2 -

  Fig. S2. Migration of MZ GFP neurons towards the ventricle at the postnatal stage in vitro. (A) Schematic of the experimental arrangement. A cortical slice from a P0 GAD67-GFP mouse was co-cultured with a P0 wild-type cortex with their MZ in contact. (B) Low magnification confocal image of the co-culture after 1 day.  The preparation was stained for MAP2 (magenta).  The explant to the top is from a GAD67-GFP mouse, judged by green fluorescence. (C) Higher magnification confocal images of the boxed area in B.  Many GFP neurons (C1) from the GAD67-GFP cortex migrated into the wild-type CP (n=10), which is discernible by the pattern of MAP2 immunofluorescence (C2, magenta in C3) (see Polleux et al., 2002). Some of the neurons in the CP extended a leading process toward the ventricular side (C, arrowheads). (D) In control cortex-thalamus co-culture, GFP neurons failed to migrate into the wild-type thalamus (n=4), indicating that MZ GFP neurons are selective about their target zones of migration.  Dotted lines indicate the border of the tissues. TH, thalamus. Scale bar: 500 µm for B; 40 µm for C,D.

• Movie 1 -

  Movie 1. Ventral view of migrating GFP neurons in a flat-mount preparation of E13.5 dorsal cortex. This movie corresponds to Fig. 2B.  The movie was taken at 5-minute intervals for 80 minutes with a confocal microscope.  Neurons indicated by arrowheads of the same colour represent the same neurons.  Lateral is downwards and rostral is towards the left.

• Movie 2 -

  Movie 2. As for Movie 1, but at a lower magnification.  Duration: 105 minutes.

• Movie 3 -

  Movie 3. As for Movie 2, but from an E15.5 mouse brain.  Duration: 120 minutes.

• Movie 4 -

  Movie 4. Dorsal view of migrating DsRed-positive neurons in a flat-mount preparation of E12.0+3.5 days dorsal cortex.  This movie corresponds to Fig. 9B.  The movie was taken at 20-minute intervals for 440 minutes with a confocal microscope.  Neurons indicated by arrowheads of the same colour represent the same neurons.  Lateral is downwards and rostral is towards the left.