Figure 2B. Copyright: Reprinted with permission from Elsevier from [doi:10.1016/S0012-1606(03)00258-6] Dev Biol 261: 251-67, Park KW; Morrison CM; Sorensen LK; Jones CA; Rao Y; Chien CB; Wu JY; Urness LD; Li DY, "Robo4 is a vascular-specific receptor that inhibits endothelial migration." Copyright 2003 [PMID:12941633]