Expression of retinoic acid binding and signalling components. A. Dorsal view of Crabp1 in the rhombic lip at e5. B. Transverse section through the cerebellar region (black dashed line in A). Crabp1 lies outside the ventricular layer. Dorsally, apparent ventricular expression is a by-product of the plane of section. C. Transverse section through the hindbrain (white dashed line in A) with the rhombic lip indicated (arrow).D. Dorsal view of an e6 embryo. E. Transverse section through the cerebellum (black dashed line in D). F. Transverse section through the caudal hindbrain (white dashed line in D) shows expression in the magnocellularis and underlying laminaris of the vestibuloacoustic nuclei, as identified by mafB  (inset). G. RARγ expression at the level of the cerebellum at e5 is expressed throughout the neural tube. Areas of lower expression correspond to descending axon tracts. H. RXRγ expression at the same axial level is ubiquitous but conspicuously elevated in the locus coeruleus, identified by the expression of TH or Phox2a (inset). I. RARγ in transverse section is uniformly expressed throughout the neural tube. J. In caudal hindbrain, RXRγ is elevated in a discrete column of neurons close to the pial surface.