Fig. 2

Blood Flow and Hemodynamic Forces Regulate vMC Recruitment

(A) Genetic and pharmacological impairment of blood flow prevent vMC recruitment. Confocal images of partial z-projections of the trunk region (somite 8–14) of Tg(kdrl:egfp)^s843;Tg(acta2:mCherry)^uto5 embryos at 3 dpf (merged and single channels) after injection of tnnt2 morpholinos or 2,3-BDM treatment. Compared to controls, vMCs (arrows) are not recruited around the DA of embryos with impaired blood flow. Scatter plots show the quantification of vMC number per 500 μm of the DA at 80 hpf. n = 15, 26, and 15 embryos, respectively. Data are represented as mean ± SD. Stars represent the results of one-way ANOVA-Dunnett’s post hoc test (^∗p < 0.05, ^∗∗p < 0.01, ^∗∗∗p < 0.001, ^∗∗∗∗p < 0.0001). g, gut.

(B) Abrogation of erythrocytes and reduced shear stress impair vMC coverage. Confocal images of partial z-projections of the trunk region (somite 8–14) of Tg(kdrl:egfp)^s843;Tg(acta2:mCherry)^uto5 embryos at 3 dpf (merged and single channels) after gata1 knockdown by morpholino injection. Compared to controls, gata1 morphants showed reduced vMCs around the DA (arrows). Scatter plots show the quantification of vMC number per 500 μm of the DA at 80 hpf. n = 15 and 23 embryos, respectively. Data are represented as mean ± SD. Stars represent the results of unpaired t tests of mean difference = 0 (^∗p < 0.05, ^∗∗p < 0.01, ^∗∗∗p < 0.001).

See also Figure S3.