Fig. 8. Rbpsuh is necessary for the maintenance of Sox9 expression after E12.5 in the spinal cord. (A-E) Transverse sections of the spinal cord from control and Nestin-Cre⁺ Rbpsuh^fl/fl mouse embryos from E11.5 to E19.5 were stained for Sox9. A-E represent montages of multiple non-overlapping images of the same section. In control embryos, Sox9⁺ cells were in the ventricular zone early in development but gradually dispursed throughout the spinal cord by E19.5. (F) In Nestin-Cre⁺ Rbpsuh^fl/fl embryos, Sox9⁺ cells were in the ventricular zone from E11.5 to E13.5, but became increasingly depleted relative to control embryos after E12.5 (three to six mice per genotype and time point). (G) Only rare Sox9⁺ cells appeared to undergo cell death at E13.5 and E14.5, but Sox9⁺ cells from Nestin-Cre⁺ Rbpsuh^fl/fl embryos exhibited increased cell death at E19.5. (H) Nestin-Cre⁺ Rbpsuh^fl/fl embryos exhibited reduced expression of Rbpsuh and Sox9 but not Scl by qRT-PCR at E14.5.