Fig. 7.

Bbs4 and Ofd1 morpholinos synergize in disrupting body axis formation and laterality in zebrafish. (A–D) Whole mount images of zebrafish embryos 28 hours after fertilization. Shown are untreated control (A) and embryos treated with 2 ng Bbs4 morpholino (B), 2 ng Ofd1 morpholino (C) and 2 ng Bbs4 + 2 ng Ofd1 morpholino (D). Only the embryo administered both Ofd1 and Bbs4 morpholinos exhibits a bent body axis. (E) Frontal view of two zebrafish embryos (28 hours post-fertilization) injected with 4 ng of Ofd1 morpholino. Red vertical lines indicate the embryonic midline, and the arrow and black curved lines indicate the position of the heart. In the left image, the heart is positioned normally on the left side of the embryo, whereas in the right image the position of the heart is reversed. (F) Histogram indicates frequency of heart laterality defects in one-day-old embryos treated with single or combined morpholinos. *P<0.001 versus control, **P<0.001 versus effects from low dose morpholinos administered individually.