Skip to main content
. Author manuscript; available in PMC: 2008 Nov 25.
Published in final edited form as: Dev Dyn. 2008 May;237(5):1359–1372. doi: 10.1002/dvdy.21536

Figure 3. Ventral midbrain is specified but cannot be maintained in the Shh-/- mouse.

Figure 3

A, B, E-J. Wholemounts oriented as in 1A. C, D. Embryos in sagittal view, rostral to the right. A, B. The expression of Pax7 (blue) is restricted dorsally in the midbrain of the control (A) and Shh-/- mouse (B) at E8 (6 somites). Gli1 expression (brown), present in A and missing in B, identifies the Shh-/- mouse. C, D. E8 (6 somites) embryos showing the complete loss of Ptc1 expression from the Shh-/- midbrain (D) compared to its control littermate (C). E, F. Pax7 expression in E8.5 (10 somites) controls is restricted to the dorsal midbrain (E). Increased Pax7 expression in the rostral, but not the caudal portion of the Shh-/- midbrain (F) at E8.5 (10 somites). The bracket in F marks the rostrocaudal extent of the midbrain. G, H. Fgf8 (brown) expression in the MHB and Pax7 (blue) expression in the midbrain in an E8.5 wild-type (9 somites; G) and Shh-/- mouse (10 somites; H). Note that the Pax7-negative territory is rostral to the Fgf8 expression domain and therefore within the midbrain. I, J. Pax7 expression demonstrating that compared to controls (I), the Shh-/- midbrain (J) is completely dorsalized by E9 (15 somites). Abbreviations: rFP: rostral floor plate; MB: midbrain; MHB: midbrain-hindbrain boundary.