Fig. 2

GB9 treatment causes vascular defects during zebrafish development. (A,B) Lateral view of GB9 treatment shows less ISV growth at the top of embryo and less or no angiogenic sprouting from the caudal vein plexus (CVP) (hollow arrow in (B)) compared to untreated controls (arrows in (A)) in Tg(flk:eGFP) that expressed GFP in endothelial cells. (C) Quantification of endothelial sprouting at CVP shows a five-fold decrease in GB9-treated fish (n = 12 in control and n = 12 in GB9 sample) at 25 hpf. (D–H) At 30 hpf, bright field images showed GB9 treatment causes minor pericardial edema ((E), arrow). In untreated control embryos, ISVs reach the DLAV at the embryo’s dorsal aspect (arrowheads in (F,H)) and the CVP formed loop structures at the tail ((H), arrows). At the same stage, ISVs show slower growth at mid-somite in the GB9 treated embryos (hollow arrowheads in (G,I)) and less endothelial cell sprouting and loop formation at CVP (hollow arrow in (I)). (J,K) Quantification of percentage of completed ISV and CVP structures in GB9-treated fish at 30 hpf shows a ~2.2-fold and ca. six-fold reduction, respectively (n = 12 in control and n = 15 in GB9 treated samples). *** refers to p < 0.0001 by an unpaired Student’s t-test. Scale bars are 100 μm for (A,B,F–I), and 200 μm for (D,E).