Normal blood vessel development in synectin^KD embryos. In all panels, head faces left and dorsal is up. Scale bars represent 50 μm in panels A-B and E-L, and 150 μm in panels C-D. DA indicates dorsal aorta; DLAV, dorsal longitudinal anastomosing vessel; and PCV, posterior cardinal vein. (A-B) Confocal side views of the trunk of 48-hpf control (A) and synectin^KD (B) Fli1:eGFP^y1 zebrafish embryos, showing normal vascular morphogenesis in the morphant embryo. Large arrow indicates the DLAV while the small arrow indicates an intersegmental vessel. (C-D) Macroscopic side views of 48-hpf control (C) and synectin^KD (D) Gata-1:DsRed embryos expressing DsRed specifically in erythrocytes. Synectin^KD embryos show a normal distribution of erythrocytes throughout the body, indicating a fully functional circulation. (E-L) Bright-field side views of the trunk of 28-hpf control (E-F,I-J) and synectin^KD (G-H,K-L) embryos stained by whole-mount in situ hybridization for a panel of arterial (Grl, E,G; EphrinB2a, F,H) and venous markers (Flt4, I,K; EphB4, J,L). No difference in expression of any of these markers could be observed in the synectin^KD embryos, indicating that arterio-venous differentiation had occurred normally in these embryos. Red and blue lines denote DA and PCV, respectively.