Fig. 1.

Generation of a dlx3b and dlx4b (dlx3b/4b) null allele. (A) Scheme of the dlx3b/4b bigene cluster at chromosome 12. Transcriptional start sites are indicated by arrows. Exon sequences with translated and untranslated regions are represented in dark and light grey, respectively. Positions of the CRISPR/Cas9 target sequences, separated by 21,045 bp, and their sequences in the wild-type and dlx3b/4b deletion allele are indicated in orange and red. Primers used for genotyping (1f, 2f and rev) are shown as half arrows. (B) In situ hybridization of dlx3b at early OEPD stages (three somites). Expression of dlx3b is absent in 25% of embryos obtained from a dlx3b/4b heterozygote incross. Scale bar: 500 µm. (C) Multiplex PCR using primers 1f, 2f and rev reveals the presence of the dlx3b/4b deletion (618 bp) and wild-type allele (473 bp). M indicates a marker for molecular size standard.