sf3b1 gain- and loss-of-function analyses. (A,B) The tstb460 phenotype is partially rescued by sf3b1 misexpression. (A) Melanophores are absent in uninjected tstb460 mutant embryos. (B) tstb460 homozygous mutant embryos were injected with hs>sf3b1 and heat-shocked 2 or 3 times (6 hpf, 10 or 11 hpf, 22 or 23 hpf), 1h/each time. Several melanophores present in the dorsal trunk region and over the yolk region in injected tstb460 mutant embryos (arrows). (C-F) Phenocopy of tstb460 mutant embryos using morpholino knockdown analysis. (C) Lateral view of a live uninjected wildtype embryo at 30 hpf. (D) Lateral view of a tstb460 homozygous mutant at 30 hpf. (E) Lateral view of a live sf3b1MO3rd morphant showing the absence of melanophores (arrowheads) and CNS (brain) cell death at 30 hpf. (F) Lateral view of a live sf3b1MOATG morphant showing phenocopy of the tstb460 mutant at 30 hpf. (G) The phenotype was more severe in the sf3b1MOATG injected tstb460 mutant as compared with uninjected tstb460 mutant, suggesting that the tstb460 allele is hypomorphic. (H) Variant transcripts in sf3b1MO3rd morphants. Lane1 and lane2: RT-PCR product from uninjected wildtype total RNA. Lane 3 and lane 4: RT-PCR product from sf3b1MO3rd morphant total RNA. (I) Western blot analysis of Sf3b1 protein levels in uninjected wildtype embryos and sf3b1MOATG morphants at 12 hpf. Lane 1: uninjected wildtype embryos; Lane 2: sf3b1MOATG morphants. (J) Schematic diagram of different sf3b1 transcripts in sf3b1MO3rd morphants. (K) Schematic diagram of different sf3b1 transcripts in hi3394a mutants.