Fig. 8. Effects of Sema4d on metanephroic development are mediated by plexin B1. (A-D) Typical examples of anti-calbindin-stained metanephroi derived from wild-type (wt) or plexin B1-knockout embryos (Plxnb1^-/-) cultured with either Sema4d or mock medium. (E-H) The Sema4d-induced inhibition of ureteric branching (E,F) and kidney size (G,H) in wild-type kidneys is lost in kidneys that lack plexin B1.^*P<0.05 when compared with mock; Student's paired t-test.