Fig. 6

Knockdown of zC2orf62 or zTTC17 in embryos results in body curvature, head defects, and heart positioning defects.

Zebrafish embryos were either not injected (n.i.) or injected with different quantities of Ctrl. MO, C2orf62_1 MO, C2orf62_2 MO, TTC17_1 MO or TTC17_2 MO and observed under a stereomicroscope. Scale bars, 200 μm. (A) Embryos injected with 5 ng C2orf62_1 MO, C2orf62_2 MO, TTC17_1 MO or TTC17_2 MO display the same phenotype at 24 hpf characterized by a curved body, a lack of defined brain structures or necrosis in the developing brain, and eye formation defects (arrows). Phenotypic traits were classified into four categories, each being associated with one grey code, as reported in the bar graph: normal (white, indistinguishable from controls), severe (clear grey, defect of brain structure formation and short body axis), very severe (dark grey, indistinguishable left/right or front/back polarity), and lethal (black). The bar graph shows the percentages of embryos in each category. Injection of 10 ng C2orf62_1 or C2orf62_2 MO or of 5 ng TTC17_1 MO results in >97% severe-to-lethal phenotypes. Injection of 5 ng C2orf62_1 or TTC17_2 MO results in about 65% severe-to-lethal phenotypes. See also the synergy between C2orf62_1 MO and C2orf62_2 MO in fig. S5. (B) Embryos were either not injected (n.i.), or injected with 1.25 to 5 ng C2orf62_1 MO or with 5 ng TTC17_2 MO, and observed at 72 hpf. Embryos injected with 5 ng C2orf62_1 or TTC17_2 MO display a curved body, incorrectly defined brain structures and heart edema (arrows). Injected embryos were classified into four categories, each being associated with one grey code, as reported in the bar graph: normal (white, indistinguishable from controls), moderate (clear grey, little body curvature and small heart edema), severe (dark grey, strong body curvature, brain defect morphology and edema), and lethal (black). The bar graph shows the percentages of embryos in each category. Injection of 5 ng C2orf62_1 or TTC17_2 MO results in about 50% severe-to-lethal phenotypes. (C) Embryos were labeled for myh6 at 30 hpf and classified into four categories according to the position of their heart (ventral views, scale bars, 200 μm): situs solitus (white), situs inversus (black), bilateral/midline positioning (light grey) and unclear/undeterminable positioning (dark grey). The bar graph shows the percentage of embryos in each category. About 20% of C2orf62_1 or TTC17_2 MO-injected embryos display situs inversus. See Figs S5 and S6 for further characterization of C2orf62_1 and C2orf62_2 MO.