Figure 3. The crucial role of the extracellular domain of CD44 in airineme extension.

(A) Airineme extension frequency did not significantly altered in transgenic embryos that overexpressed the intracellular domain of cd44 (cd44aICD) specifically in the xanthophore-lineages or macrophages, (F(₂, ₁₄)=1.736, P=0.2121, 17 embryos in total). (B) Overexpression of CD44a with a truncated extracellular domain (cd44aTMICD) exhibited significant reduction in airineme extension frequency in both the xanthophore-lineages and macrophages, (F(₂, ₁₃) = 23.62, P<0.0001, 16 embryos in total). Airineme extension frequency was even further significantly reduced when cd44aTMICD was overexpression in both cell type simultaneously, (F(₂, ₁₇)=18.04, P<0.0001). (C) Airineme extension frequency was restored when the WT CD44 was overexpressed in embryos already expressing cd44aTMICD in the xanthophore lineages, (P=0.5767, 4 embryos each). Statistically significant results were evaluated using a One-way ANOVA, followed by a Tukey’s HSD post hoc test or a Student’s t test. Error bars indicate mean ± SEM.