Fig. 4

Sorbs1 is expressed in the vasculature throughout development. A Z-maximum projections of confocal images of the trunk vasculature of WT embryos at the indicated time of development and stained for sorbs1 transcripts (magenta dots) and for vessels (gfp immunostaining, green) using FISH. The DA and PCV are delineated in red and blue. zx sections are shown on the right to show presence of signal inside the vessels. The enrichment of the FISH signals (cumulative area of the spots) in the DA and in the PCV compared to non-endothelial tissues was quantified for each time point (see the “Methods” section for details). Scale bar represents 75 μm. DA, dorsal aorta; PCV, posterior cardinal vein; ISV, intersegmental vessel; PLs, parachordal lymphangioblasts (n = 4 embryos (24 hpf); n = 5 embryos (32 hpf); n = 6 embryos (48 hpf); n = 5 embryos (72 hpf); ns = non-significant; ***P < 0.001; **P < 0.01; *P < 0.05; Mann–Whitney U-test for comparing the expression between the DA and the PCV and Kruskal–Wallis test for testing the endothelial enrichment). B Quantification of the expression of sorbs1 and two veinous/lymphatic markers, prox1a and lyve1b, in arterial and venous cell types across development from the single-cell sequencing Daniocell database. The color gradient, ranging from light to darker violet, represents the mean gene expression level in cells. The size of each dot corresponds to the percentage of cells expressing the target gene within the cluster