Figure 5

Effects on tangential migration of ectopic Hoxa2 are rhombic-lip-autonomous A comparison of E6 quail-chick chimaeras with different combinations of targeted Hoxa2 overexpression (red), in which the relative proportions of dorsal and ventral rhombic lip derivatives are compared (right). (A) Uninfected quail (Q) donor tissue in a normal chick (C) host (Q into C) gives rise to EGL cells and a small number of neurons in ventral r1 (white arrow). (B) Quail cells expressing Hoxa2 in a normal host (Q-Hoxa2) bypass the EGL and condense ventrally. (C) Normal quail cells migrate in a host expressing ectopic Hoxa2 (Q into Hoxa2 C) migrate as controls. Scale bar for high-power insets = 100 μm. egl – external granule cell layer; ml – midline.