|
Fig. 1 Generation of the nkx2.4b zd20 null allele. A, Transcription activator‐like effector nucleases (TALENs) were targeted to exon 1 of the nkx2.4b gene, upstream of exon 2 which encodes the DNA‐binding homeodomain (HD). The 5‐bp deletion in zd20 is underlined in the spacer sequence located between the two TALENs binding sites. B, DNA alignment of nkx2.4b in wild‐type and zd20 mutant fish showing the 5‐bp deletion, identified with a red bar. C, Wild‐type Nkx2.4b amino acid sequence—serine 71 is labeled in magenta. An arrowhead marks the exon 1‐exon 2 boundary, and the homeodomain in exon 2 is underlined. D, The zd20 allele translation showing the predicted amino acid sequence resulting from the frameshift in grey, with a stop codon at position 114