Fig. 6

miR-139 and miR-24 Mutants Are Broadly Affected by Stress

(A and B) Schematic depicts the duration of chemical exposure or environmental condition used to test stress sensitivity of miR-139-regulated (A) and miR-24-regulated (B) vascular traits in the absence of miRNA activity. Stressors were administered at doses that minimally affect wild-type as indicated (see Table S1).

(C and D) Arrows point to ectopic ISV branches in 54-hpf miR-139Δ/Δ embryos treated with pro-angiogenic drugs: BIO (n = 24) and GSI (n = 50–55 embryos). Controls were treated with DMSO vehicle (n = 17–24 embryos).

(E) Arrows highlight stunted ISV branches in 27-hpf miR-139Δ/Δ embryos treated with anti-angiogenic VEGF inhibitor SU5416 (n = 25–27 embryos). Controls were treated with DMSO vehicle (n = 17–25 embryos).

(F) Arrows show ectopic ISV branches in 54-hpf miR-139Δ/Δ embryos exposed to high-temperature stress (n = 31–44 embryos/genotype).

(G) Yellow arrows show region captured in zoom images. White arrow points to hypersprouting of DLAV endothelial cells in 52 hpf miR-139Δ/Δ embryos exposed to 4 hr of hypoxia (n = 40–45 embryos/genotype).

(H) Arrows indicate the HA of BIO-treated embryos.

(I–M) Quantification of 56-hpf HA length (μm) upon treatment of BIO or DMSO (n = 12–24 for all genotypes except n = 6 for quadruple mutant embryos, I); GSI or DMSO (n = 15, J); SU5416 or DMSO (n = 11–16, K); high or control temperature (n = 38–50, L); and hypoxia or normoxia (n = 24, M). S = single, D = double, T = triple, Q = quadruple mutant embryos.

All images were captured with a 25× objective. All bar plots represent mean ± SEM, and significance comparisons between samples are as indicated. n.s., not significant (p > 0.05); ^∗p ≤ 0.05, ^∗∗p ≤ 0.01, ^∗∗∗p ≤ 0.001, ^∗∗∗∗p ≤ 0.0001, two-tailed Mann-Whitney U test.