Fig. S3

Fig. S3 Vegfc^um18 mutants display primary defects in lymphatic progenitor and vein sprouting. (A) Diagram describing lymphatic vessel formation in zebrafish. (1) Dorsal sprouting of parachordal lymphangioblasts (PLs) from the posterior cardinal vein (PCV) at 1.5-2 dpf. (2) Ventral migration of PLs along the horizontal myoseptum. (3) Ventral migration of PLs to a position between the dorsal aorta and posterior cardinal vein to form the TD. (B-D) Confocal microangiographs of trunk blood vessels in Tg(fli1a:egfp)^y1 embryos at 2 dpf. Anterior is to the left, dorsal is up. White arrows indicate position where PLs normally form. (B) Wild-type embryo. (C) vegfc^um18/+ heterozygous embryo. (D) vegfc^um18 homozygous mutant embryo. (E) Quantification of PL formation. Values indicate the percentage of embryos of the indicated genotype that display either presence or absence of PLs. (F,G) Confocal microangiographs of trunk blood vessels at 3 dpf. Anterior is to the left, dorsal is up. DA, dorsal aorta; PCV, posterior cardinal vein; SegA, segmental artery; SegV, segmental vein. White arrowheads indicate SegA. (F) Wild-type sibling embryo. (G) Homozygous vegfc^um18 mutant embryo. (H) Quantification of percentage artery and vein connections in wild-type and vegfc^um18 mutant embryos. Mutants were identified as those lacking a PHBC at 30 hpf. At 3 dpf, embryos of both phenotypic classes were scored for the connection of intersegmental vessel to either DA or PCV based on blood flow. The values shown are based on the average of three independent experiments. Scale bar: 25 μm.