Approximately half of the Foxc2-heterozygoes embryos generated in C57BL/6 background are grossly indistinguishable from wild type embryos (A, B). The other half develops edema (C, arrows) by E14.5. Analysis of frontal sections from these embryos revealed one LVV in the normal-looking Foxc2+/− embryos (E, arrow). The edematous embryos lack LVVs (F, arrowheads). (G-I) SEM of the LVV-complex from control embryos revealed two LVVs (G, magenta) in control and one LVV (H, magenta) in non-edematous Foxc2-heterozygote embryos. In contrast, no LVVs are seen in edematous Foxc2-heterozygoes (I). Instead, a few elongated cells with the characteristics of LVV-ECs are seen (magenta).
Statistics: n= 3 for A-G; n = 4 for H; n = 2 for I.
Abbreviations: SVC, superior vena cava; SCV, subclavian vein; LS, lymph sac; IJV, internal jugular vein.
Scale bars: 50 µm