Fig. 2

nhsl1b is disrupted in fh131 mutants. (A) Genetic mapping of 1444 fh131 mutant zebrafish embryos identifies a genetic interval on chromosome 20 containing nhsl1b. (B) Genomic structure of nhsl1b. Black boxes mark exons 1-8. (C) Sequence trace of a nonsense mutation in nhsl1b in fh131 mutants. (D) Phylogram of the NHS protein family. Mm, mouse; Dr, zebrafish; Hs, human; Dm, Drosophila. (E,F) Tg(isl1:GFP)rw0 expression in an embryo injected with a splice-blocking morpholino targeted to the nhsl1b exon 4-intron 4 boundary (E) or a translation-blocking morpholino targeted to the ATG of exon 1 (F). (G-I) Tg(isl1:GFP)rw0 expression in PCR-genotyped embryos heterozygous for nhsl1b^fh131 (G) or for the nhs1b^fh280 nonsense allele generated by TILLING (H) and in nhsl1b^fh131/280 trans-heterozygotes (I). Note the strong block to FBM migration in the trans-heterozygotes indicating that fh131 and fh280 are alleles of the same gene. r4-r7, rhombomeres 4-7. Scale bar: 20 µm.