Fig. 4
Inhibiting Vegf signaling impairs linearisation and VE-cadherin tension changes during arterial maturation. (a, b) Junctional morphology of ECs in the DA (Venus, grey) in uic (top) and kdr/kdrl morphants (bottom) at 2 dpf (a) and 3 dpf (b). Scale bar = 10 μm. c Number of ECs quantified at 2 dpf (uic n = 9, kdr/kdrl MO n = 6 embryos) and 3 dpf (uic n = 10, kdr/kdrl MO n = 7 embryos). Error bars represent mean ± s.d.; 2 dpf uic–2 dpf kdr/kdrl MO ****p < 0.0001 from unpaired two-sided t test, 3 dpf uic–3 dpf kdr/kdrl MO **p = 0.0068 from unpaired two-sided Mann–Whitney test. d Junctional linearity index of junctions in uic and kdr/kdrl morphants at 2 dpf and 3 dpf. Error bars represent mean ± s.d.; 2dpf uic–3dpf uic ****p < 0.0001; 2 dpf kdr/kdrl MO–3dpf kdr/kdrl MO, p = 0.0862 from unpaired two-sided Mann–Whitney test. e, f Ratio-metric FRET values of uic and kdr/kdrl morphants at 2 dpf e (uic n = 74 junctional ROIs from n = 9 embryos, kdr/kdrl MO n = 86 junctional ROIs from n = 6 embryos) and 3 dpf f (uic n = 62 junctional ROIs from n = 10 embryos, kdr/kdrl MO n = 58 junctional ROIs from n = 7 embryos). Error bars represent mean ± s.d.; ***p = 0.0007; *p = 0.0391 from unpaired two-sided t test. g Ratio-metric FRET values from 1% DMSO controls (n = 48 junctional ROIs from n = 6 embryos) versus SL327 (4 μM/1% DMSO)-treated embryos (n = 66 junctional ROIs from n = 10 embryos). Treatment from 20 hpf to 3 dpf. Error bars represent mean ± s.d.; ****p < 0.0001 from unpaired two-sided t test. h Junctional linearity index in 1% DMSO treated controls (n = 32 junctional ROIs from n = 6 embryos) versus SL327 (4 μM/1% DMSO)-treated embryos (n = 56 junctional ROIs from n = 10 embryos). Error bars represent mean ± s.d.; **p = 0.0045 from unpaired two-sided Mann–Whitney test. i Junctional morphology of ECs in the DA (Venus, grey) at 3 dpf in 1% DMSO and SL327 (4 μM/1% DMSO) treated embryos at 3 dpf. Scale bar = 10 μm. j Ratio-metric FRET values from uic (n = 45 junctional ROIs from n = 8 embryos) versus kdr/kdrl morphants incubated in 1% DMSO as a control (n = 43 junctional ROIs from n = 9 embryos) and kdr/kdrl Y-27632-treated morphants (50 μM/1% DMSO, n = 40 junctional ROIs from n = 9 embryos) at 2 dpf. Error bars represent mean ± s.d.; uic–kdr/kdrlMO + DMSO ****p < 0.0001; kdr/kdrlMO + DMSO – kdr/kdrlMO + Y-27632 ***p = 0.0005 from unpaired two-sided t test