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Fig. 7 Truncation of Ve-cadherin inhibits both JBL and endothelial cell remodeling. a Images of anti-ZO1 immunostained junctions in cdh5ubs25/+ and cdh5ubs25/ubs25 embryos. Arrows point to medial site of the junction. b Quantitation of the medial and lateral junctional thickness, based on immunostaining for ZO1; cdh5ubs25/+, n = 44 junctions (17 embryos); cdh5ubs25/ubs25, n = 40 (11 embryos); wild-type n = 28 (9 embryos). Black lines are medians. Non-parametric Kruskal–Wallis statistical test was used. c Quantitation of the duration of JBL based on EGFP-UCHD signal; cdh5ubs25/+, n = 122 (8 embryos), cdh5ubs25/ubs25 n = 103 (8 embryos) and wild-type n = 43 (3 embryos). All embryos carry the UAS:EGFP-UCHD transgene Tg(fli:GFFubs3;UAS:EGFP-UCHDubs18). d–l Tg(kdrl:EGFPs843);cdh5ubs25/+ (d–g) and Tg(kdrl:EGFPs843);cdh5ubs25/ubs25 (h–k) embryos stained for VE-cadherin (rabbit antibody, green) and ZO1 (red). Individual channels are shown in inversed contrast. Both wild-type and mutant VE-cad show junctional localization (solid arrow in panels d, f, h, and j). The junctional gap in the VE-cadherin staining of a SeA in a mutant embryo (cdh5ubs25/ubs25) is marked with dashed double arrow in panel h. l Quantification of the length of junctional gaps in control (cdh5 ubs25/+, n = 72 gaps, 23 embryos) and mutant (cdh5ubs25/ubs25, n = 139 gaps, 33 embryos) embryos. Black lines are medians. Non-parametric Mann–Whitney statistical test was used. m Still images from a confocal time-lapse of endothelial nuclei (Tg; kdrl:nlsEGFPubs1) in wild-type or cdh5ubs25/ubs25 embryos during SeA formation. T tip cell, S1 stalk cell 1, S2 stalk cell 2; double-headed arrow indicates the distance of S1 and S2 nuclei. n Quantification of movement of stalk cell 1 (S1) nuclei in relation to stalk cell 2 (S2) nuclei during cell rearrangements in SeA; cdh5ubs25/+, n = 22 SeA (4 embryos); cdh5ubs25/ubs25, n = 17 SeA (4 embryos); wild-type n = 20 SeA (4 embryos). Black lines are medians. Non-parametric Kruskal–Wallis statistical test was used. Scale bars 5 µm (a), 10 µm (d, h, m)