Figure 4

URP detection by immunohistochemistry. (a) Parasagittal section of caudal telencephalon showing increased immunostaining for URP in an oval area corresponding to nucleus HVC, immediately beneath the lateral ventricle. (b) Box inside HVC enlarged from panel a, showing cytoplasmic immunostaining pattern of a subset of cells (small inset, Hoechst counterstaining revealing all cell nuclei). (c) Field inside Area X, with negligible immunostaining. (d) Absence of primary antibody demonstrates negligible non-specific fluorescence (field inside HVC as in b). (e) Large labelled cells in brainstem nucleus nXIIts. (f) Large labelled cells in brainstem supraspinal nucleus (SSp). (g) Intense puncta of URP staining suggestive of synaptic terminals in RA. Bar = 100 µm (a) or 50 µm (b–g).