Figure 1From: Fgf signaling controls the telencephalic distribution of Fgf-expressing progenitors generated in the rostral patterning center Generation and validation of Fgf8 CreER and Fgf17 CreER mouse lines. (A) In the Fgf8 CreER allele, the first 20 nucleotides of exon 1 coding sequence were replaced with CreER-SV40 pA-loxP-neo-loxP cassette, and the long arm of homology began 12 nucleotides upstream of the exon 1/intron 1 junction. In the Fgf17 CreER allele, all exon 1 coding sequences were replaced with CreER-SV40 pA. All Fgf17 intronic sequences were included in the targeted allele, but intron 2 was interrupted by insertion of the loxP-neo-loxP cassette and, further downstream, by a small insertion of MCS restriction enzyme sites. Symbols: small arrows, genotyping oligos; red rectangles, Southern blot probes. (B) Fgf8 CreER/+ and (C) Fgf17 CreER/+ Southern blots demonstrating correct targeting. (D) Fgf8 and Fgf17 whole mount ISHs (frontal view) showing mRNA expression in the rostral telencephalon of 12-s embryos. (E,F) E10.5 ISHs (horizontal sections) comparing Fgf8 versus Cre mRNA in an Fgf8 CreER/+ brain (E), and Fgf17 versus Cre mRNA expression in an Fgf17 CreER/+ brain (F). Sequential panels in (E) and (F) show successively more caudal planes of section. Abbreviations: B, BamHI; E, EcoRI; N, NdeI; S, SacI; X, XhoI; Di, diencephalon; MH, midbrain/hindbrain patterning center; Hy, hypothalamus. See also Additional file 1: Figure S1.Back to article page