Fig. 1.

Assay of DNaseI hypersensitive regions near the Otx2 gene for CRM activity in the retina. (A) Twenty-five DNaseI hypersensitive regions (The ENCODE Project Consortium, 2011; Vierstra et al., 2014), O1-O24, flanking the Otx2 gene are highlighted. (B) Individual DNaseI hypersensitive regions were cloned into the Stagia3 reporter plasmid and electroporated into P0 mouse retinas. The retinas were cultured as organ cultures for 5 days ex vivo. The CAG-mCherry plasmid served as the electroporation efficiency control. (C) Seven out of the 25 DNaseI hypersensitive regions drove AP expression. The O5, O7 and O9 CRMs (highlighted) became the focus of this study. Scale bars: 0.5 mm.