Fig. 9. RFX4_v3 in situ staining in the region of the developing SCO. (A-D) Progressively rostral-to-caudal sections through the brain of a normal embryo at E16.5. The box labeled F in section C contains the SCO and the aqueduct of Sylvius. This region is shown enlarged at E14.5 (E), E16.5 (F) and at the time of birth (P0; G). Note the high level expression of the RFX4_v3 transcript in the region of the developing SCO in E, and in the SCO itself in F,G. Scale bars: 500 µm for A-D; 100 µm for E-G. cx, cerebral cortex; ch, choroid plexus; DT, dorsal thalamus; HY, hypothalamus; me, mesencephalon; cb, cerebellum; P, pituitary; ST, striatum; ep, epiphysis.