Fig. 2. Reduced and scattered expression of Lhx4 and ER81 by facial MN in reeler mice. The pial side of whole-mount E14.5 control (A,C) and reeler mutant (B,D) mice is shown. (A) Lhx4 is expressed in the trigeminal motor nucleus (V), a column of cells at the r4/r5 level, as well as in the medial part of the facial nucleus (circled), in control embryos. (B) In reeler mutants, the Lhx4-positive area in the facial nucleus is reduced in size (circle), and positive cells were observed deeper in the parenchyme (arrowheads). Most of the rostral column is not present at the pial surface. (C) In control embryos, ER81 mRNA is expressed in cells in the most lateral part of the facial nucleus, and in the inferior olive precursors cells. (D) In reeler mutants, ER81 labeling is mainly localized in the lateral part of the facial nucleus (arrowheads), but in a more scattered pattern than in controls. IO, inferior olive.