Reelin-Dab1 signaling is required for orientation of neuronal somata and primary neurites. (A) The angles of the neuronal soma (θ) and primary neurite (φ) with respect to the shortest line from the somal tip to the pial surface (red line in A) were measured in 3-D using a custom MATLAB script. Only GFP + neurons within 50 μm of the pial surface were included for analysis. Scatter and box plots of somal orientation (B) and primary neurite orientation (C) in all four explant conditions. Both r/r Ct-CM and s/s Ct-CM neurons demonstrated significant somal and primary neurite misorientation compared to wt neurons. Injection of Rln-CM significantly rescued both somal and primary neurite orientation angles in r/r mutant explants. Dashed lines on both scatter and box plots represent mean values; solid lines on box blots represent median values. Box plots display upper and lower quartiles; whiskers represent 90th and 10th percentiles. Kruskal-Wallis one-way ANOVA on ranks with post-hoc Dunn tests were performed between treatment conditions. * p < 0.05, as compared to wt controls. wt analysis: 209 neurons from 22 explants across 9 litters. r/r Ct-CM analysis: 105 neurons from 7 explants across 5 separate litters. s/s Ct-CM analysis: 49 neurons from 3 explants across 3 litters. r/r RlnCM analysis: 86 neurons from 8 explants across 4 separate litters.