Fig. 6. Notch-mediated DeltaD endocytosis results in DeltaD degradation. (A-B') Distribution of DeltaD-HA in WT and Notch MO zebrafish embryos. In vitro synthesized mRNA encoding DeltaD-HA and Myc^PM was co-injected with control (WT in A,A') or notch1a and notch3 MOs (Notch MO in B,B'). Embryos are labeled with anti-HA mAb (green) and anti-myc pAb (red) at 80% epiboly stage. More DeltaD-HA is localized in cytoplasmic puncta in WT than in Notch MO cells. (C-H') Comparison of DeltaD-HA (green) and Myc^PM stability with (F-H) and without Notch morpholinos (C-E). DeltaD-HA expression reduces from 80% epiboly (C) to the two-somite stage (2 ss) (D) and is barely detectable at the five-somite stage (5 ss) (E) in WT. By comparison, Myc^PM expression levels are progressively increased from 80% epiboly to 5 ss (C'-E'). In Notch MO embryos, Delta-HA (F-H) behaves like Myc^PM (F'-H') and its expression is not decreased.