Figure 1.
In situ hybridization of mouse embryos shows HFH-4 expression in the choroid plexus epithelium. In situ hybridization of sagittal sections of paraffin-embedded mouse embryo with 33P-labeled antisense HFH-4 RNA probe. (A) HFH-4 expression in 11 day p.c. mouse embryo. The darkfield panel demonstrates that HFH-4 expression (white) is restricted to the neuroepithelium lining the roof of the hindbrain (RHB) in the fourth ventricle, in regions separating the mesencephalic vesicle (MV), and telencephalic vesicle (TV) and in the floorplate (Fp) of the neural lumen (NL). Indicated are other structures that do not express HFH-4 including nasal cavity (NC), oropharynx (Op), heart (He), liver (Li), and hindlimb (HL). (B) HFH-4 expression in 13.5 day p.c. mouse embryo. HFH-4 is expressed in the choroid plexus (CP) epithelium of the fourth ventricle (FV) and lateral ventricle (LV) and in the epithelium lining part of the mesencephalic vesicle (MV). No HFH-4 expression is observed in lung (Lu), upper lip (UL), lower lip (LL), vertebrae (Ve), and pericardial cavity (PC). (C) Enlargement of 13.5 day p.c. embryonic brain shows that HFH-4 expression is restricted to the choroid plexus epithelium and ependymal (epithelial) cells lining the lateral, mesencephalic, and fourth ventricles. (D) Enlargement of the fourth ventricle of 13.5 day p.c. embryonic brain shows HFH-4 expression in the choroid plexus epithelium.