Figure 6

Expression of cad7 in the motor neurons and precerebellar systems. A-E: Expression of cad7 and cad20 on serial cross-sections from the hindbrain of E14.5 rat embryo at r7 level. (B) High magnification of the image shown in A. Expression of cad7 and cad20 is detected in hypoglossal motor nuclei (nXII) expressing Islet1/2 (A, B, C and E). No expression of cad7 is seen in the ventricular zone (VZ) of the dorsal area (D). F-O: Expression of Pax6, cad7 and cad20 on serial cross-sections at E18.5. Pax6 protein is detected in both the lower rhombic lip (LRL) (F), posterior extramural migrating stream (pes) (J and arrows in L) and the external cuneate nucleus (ECN) (bracket in J). Cad7 is expressed in nXII (bracket in G), vagus motor nuclei (nX) (arrowhead in G), lateral reticular nuclei (LRT) (arrow in G), the ECN (bracket in K), the nucleus of the solitary tract (Sol), and in the intermediate reticular zone (IRt). Cad7-expressing cells are migrating on the surface of the brain, which is similar to Pax6-expressing cells (arrows in L, M and arrowheads in N and O). Cad7 is also expressed in the medial accessory olive (MAO) nuclei expressing cad6 (G and I). Cad20 is expressed in nXII but not in nX (bracket in H). P-S: Serial cross-sections of E18.5 Pax6 homozygous mutant rat (rSey²/rSey²). Pax6 protein is undetectable (P), while expression of cad7 is detected in LRT (arrow in Q) and MAO expressing cad6 (S). nXII motor nuclei and ECN are missing in the Pax6 homozygous mutant (bracket and arrowhead in Q, respectively). The expression of cad20 is also undetectable, which is similar to the cad6 expression (bracket in R and S). T: Summary of expression of cad7 and cad20. Scale bars: 300 μm in A and E and F-I; 100 μm in B and C; 200 μm in D, J-M and P-S; 50 μm in N and O.