Figure 4

Immunohistochemistry of Prox1 embryos for lymphatic markers. E13.5 embryos were analyzed for the markers VEGFR-3 and Podoplanin on the jugular vein (JV) of control and double transgenic Prox1 embryos. (A) In control samples VEGFR-3 expression is relatively low in comparison to (B) Prox1 DT embryos (arrows). (C) In control embryos, Podoplanin is found expressed on the jugular vein during early development, however it begins to be downregulated and moves to the lymph sac (LS). (D) In contrast, overexpression of Prox1 results in the sustained expression of Podoplanin on the jugular vein (JV; arrowheads) as well as the enlarged lymph sac (LS). Scale bar: 100 μm.