Figure 2. Raldh3 is responsible for RA activity in neurospheres derived from the LGE but cortex-derived neurospheres lack RA activity.

(A–D) Neurospheres generated from the LGE of E14.5 wild-type (WT) embryos exhibit Raldh3 immunoreactivity and they induce RA activity when co-cultured with F9-RARE-lacZ RA-reporter cells (n = 4); neurospheres derived from Raldh3−/− LGE always lacked both Raldh3 detection and RA activity (n = 4). (E–H) Neither Raldh3 nor RA activity were detected in cortex-derived neurospheres from either wild-type or Raldh3−/− (KO) embryos (n = 4).