Non-cell autonomous Otx2 homeoprotein regulates visual cortex plasticity through Gadd45b

A better understanding of how Otx2 regulates plasticity in the visual cortex requires that its non-cell autonomous transcription targets be identified. We dissected layer IV of the visual cortex and used RNA-sequencing to analyze gene expression at postnatal day 30 (P30) and P100 in wild-type (WT) and Otx2+/GFP heterozygotes mice. The rationale is that CP plasticity is opened at P30 in WT but not in Otx2+/GFP mice, given that genetic deletion delays CP opening (Sugiyama et al., 2008), and that the CP is closed at P100 in WT mice and not yet in Otx2+/GFP mice. Thus, genes with similar expression at P30 in Otx2+/GFP and at P100 in WT mice but with a different level of expression during the critical period (P30 in WT or P100 Otx2+/GFP mice) were considered as potential genes involved in plasticity. Examination of genes expression at P30 and P100 in wild-type and Otx2 (+/GFP) mice. 4 mice were pooled per condition and experiment was done in duplicate.