Fig. 5

Sim1 knockdown eliminates itnp mRNA expression. Sim1 knockdown by injection of translation inhibiting Morpholino oligonucleotides (MO) significantly disrupts itnp mRNA expression. Three different amounts, 0.125, 0.25, and 0.5 ng/embryo, of sim1 MO and 4-base mismatched “control MO” were injected into one to four cell stage embryos. At 0.25 and 0.5 ng/embryo, sim1 MO injections resulted in a significant elimination of itnp-expressing cells at 52 hpf. Only 47 and 19% of embryos, respectively, maintained full itnp expression following MO disruption at these concentrations (p < 0.0001). Dark grey bars indicate the percentage of embryos with full itnp expression (∼100 cells) following MO injections. Light grey bars indicate the percentage of embryos with reduced itnp expression below ½ of normal (from 1 to ∼50 cells). The number of embryos injected is designated by n. The asterisk indicates statistically significant differences in mean percentage of embryos exhibiting full expression for sim1 MO, from uninjected and “control MO” injected, revealed through a Tukey HSD analysis.