Figure 2

The cbln12 promoter drives transgene expression in granule cells (GCs). (A) Genomic structure of the cbln12 gene. cbln12 has four exons and a total length of about 4.2 kbp. The start codon is in exon 2, and the stop codon is in exon 4. We isolated a 2-kbp fragment extending upstream from the start codon (cbln12 promoter). (B) Schematic drawing of the Tol2 plasmid used to express Venus in the GCs. We fused the cbln12 promoter to Venus cDNA and inserted it into a Tol2 vector. This construct was used to establish Tg(cbln12:Venus) lines. (C–E) Immunostaining of 5-days post fertilization (dpf) Tg(cbln12:Venus) larvae with anti-GFP (green) and anti-Neurod1 antibodies (magenta). Venus (Ca,Da,Ea), Neurod1 (Cb,Db,Eb), and merged images (C,D,E) are shown. Dorsal views with rostral to the left (C,Ca,Cb,D,Da,Db) or to the top (E,Ea,Eb). (D,E) High-magnification images of the boxes in (C,D). Venus was expressed in the Tel, the TL, and the Cb. In the medial region and the caudal edge of the Cb, some Neurod1⁺ cells did not express Venus (D). These were probably immature GCs. In the ventral region of the Cb (E), most of the Neurod1⁺ neurons co-expressed Venus (E). (F) Sagittal section of an adult Tg(cbln12:Venus) brain was stained with an anti-GFP antibody. Scale bars: (C) 100 μm, (D) 20 μm, (E) 10 μm, and (F) 200 μm.