Statistical analysis
All data were assumed to be normally distributed. Statistical difference between the conditions for the in vitro overexpression experiments was determined using one-way analysis of variance (ANOVA) followed by Bonferroni’s post-hoc test for multiple comparisons. For the Western blot analysis, two-tailed unpaired t-test was used (dual comparison). Neuronal migration was analyzed based on the proportion of electroporated cells targeted to the cortical plate at P1 (defined as the most proximal 40% of dorsoventral distance between the pia and ventricle (first 4 of 10 equally-spaced bins)) or to layer 2/3 of the somatosensory cortex, defined as the proximal 30% of dorsoventral distance between the proximal 10% of the cortex (assumed to represent layer 1) and ventricle (bin 2-4 of equally-spaced bins). For neuronal migration analyses, we used a minimum of 3 targeted pups per condition.