Figure 1. Tbr1 transcriptional regulation in the neonatal cortex.

(A) Volcano plot of genes up-regulated (red) and downregulated (blue) in FACS purified layer 6 neurons from P5 Tbr1^layer6 homozygous mutant SSCx. Black dots represent the genes that did not reach statistical significance (adjusted p value > 0.05). The size of each point represents the difference in the median gene expression between Tbr1^wildtype and Tbr1^layer6 mutant (large dots mean large differences). (B) P5 transcriptomic comparison of DEX genes between layer 5^wildtype vs. layer 6^wildtype and Tbr1^layer6 homozygotes vs. layer6^wildtype. With respect to genes that mark wildtype layer 5 (red genes), we observed eight genes with increased expression in the Tbr1^layer6 mutants (p < 0.05). With respect to genes that mark wildtype layer 6 (blue genes), we observed 13 with reduced expression in the Tbr1^layer6 mutants (p < 0.05). However, there were 14 of the layer 5 and layer 6 marker genes whose expression did not significantly change in the Tbr1^layer6 mutants (Fig. 1B). Genes with layer 5-like transcriptome profile (green box) and layer 6-like expression profile (black box) are indicated. See also Figure S1 and Tables S1, S2 and S3.