Figure 6. Multiple markers reveal shrinkage of the somatosensory VB on loss of LDB1. A–F, Sections from E17.5 control (A, C, E) and NesCre;Ldb1lox/lox (B, D, F) embryos at three rostro-caudal levels. A, B, Expression of Ldb1 mRNA in E17.5 control (A) and NesCre;Ldb1lox/lox (B) brains. In the mutant, Ldb1 expression is undetectable in a broad region of the dorsal thalamus (asterisks, B), while expression in the cortical plate (black arrowheads, A, B) and hippocampus persists. C–F, Chst2 expression is seen at the perimeter of the VB nucleus (ovals, C), and Prox1 expression excludes the VB nucleus leaving a distinct negative zone (oval, E). These features are not revealed in mutant sections (D, F), in which only a small Prox1 negative domain is seen (solid line, F). Black and open arrowheads identify the PO and the dLGN, respectively, which appear to be present in both control and mutant brains. Scale bars: 500 μm.