Fig. 4

Enhanced Phenotypic Variability in Hypobranchial Artery Sprouting with Diminishing miR-24 Activity

(A) sox9a WISH labeling chondrocyte progenitors (left) and Alcian blue-stained cartilage (right) in the ventral head of wild-type and miR-24 mutant embryos (n ≥ 6 for all genotypes except n = 2 for quadruple mutants). Numbers indicate the position of pharyngeal arches 1–7. miR-24 genotypes are categorized as in Figure S2B.

(B) Ventral view (25×) of 54-hpf head vasculature. Magnified images depict the spectrum of HA phenotypes (dotted outlines) for each genotype. The HA sprout most representative of the genotype is indicated with a yellow arrow and is depicted in the zoomed-in picture with a yellow HA label. White arrows point to aortic arches (AA).

(C) Bar plots show the average of replicate means ± SEM of HA length (μm) at 54 hpf (n = 4 replicates).

(D) Violin plots show 54-hpf HA length (μm) probability density distributions. Solid lines in box plots depict median values. Phenotypic variability was statistically different from wild-type as determined by the Levene's test (n = 40 embryos). Single: ^∗p = 0.04; double: ^∗∗∗∗p = 5.77 × 10⁻⁶; triple: ^∗∗∗p = 3.46 × 10⁻⁴; quadruple: ^∗∗∗p = 7.57 × 10⁻⁴

(E) Bar plots show average replicate SD ± SEM of HA length (μm) at 54 hpf (n = 4 replicates).

For all bar blots, S, single; D, double; T, triple; Q, quadruple mutant. Significance calculations were relative to wild-type embryos. n.s., not significant (p > 0.05); ^∗p ≤ 0.05, ^∗∗∗p ≤ 0.001, ^∗∗∗∗p ≤ 0.0001, two-tailed Mann-Whitney U test unless otherwise indicated.