Figure 2

Nrp1 and Nrp2 expression defines distinct cranial NCC populations along the anteroposterior axis. (A-D) Whole mount immunofluorescence analysis of Nrp1 and Nrp2 on E9.0 Wnt1Cre; Z/EG embryos in which all NCCs were labelled by GFP expression (B). In addition to staining of NCCs, both Nrp1 and Nrp2 were present in blood vessels within and around the r2 and r4 streams. (C-D) Antibody staining showed that Nrp1 expression was restricted to the r4 stream of NCCs (closed arrowhead) and Nrp2 was restricted to the r2 stream of NCCs (open arrowhead). (E-H) Longitudinal sections through the head confirmed that Nrp1 expression was indeed within NCCs of the r4 stream and not in the r2 stream (delta), while Nrp2 staining was within NCCs of the r2 stream and not in the r4 stream (closed arrowhead). Nrp1 and Nrp2 antibodies also labelled the major blood vessels (bv). e, eye; ov, otic vesicle. Scale bar = 100 μm.