rapgef1-knockdown reduced survival rate and caused alteration in gross morphology
Both E2I2-MO and ATG-MO exerted negative influences on the gross morphology of zebrafish. We observed general abnormality ofrapgef1a -knockdown zebrafish embryos, especially in the curved body axis and brain patterns (Figure 4 (A) and (B)). The percentage of embryos with body defects was much higher in rapgef1a -knockdown animals than in controls (Figure 4 (C)). Also, the survival rate of zebrafish embryos for a 5-day time course was significantly lower in therapgef1a -knockdown group than in controls (Figure 4 (C)).
To evaluate the deleterious effect of human mutant RAPGEF1transcript and as a proof-of-concept approach, we co-injected the E2I2-MO and the human RAPGEF1 transcripts with and without the aforementioned patient mutation. The rescuing capacity of human wildtypeRAPGEF1 transcript was obvious in the zebrafish with curved body axis and brain patterning defects, while the human mutant RAPGEF1transcript showed no rescue effect (Figure 4 (D) and (E)). In parallel, the percentage of embryos with defects was to some extent promoted by the human wildtype RAPGEF1 transcript but not by the mutant one (Figure 4 (F)). The same effect was observed in the survival rate (Figure 4 (F)).