Figure 5

Re-expression of Pax6 induces extensive neurogenesis from Pax6^-/- ES cells. (A, B) Immunocytochemistry for Pax6 (green) does not label cells derived from the founder Pax6^-/- line SeyD1 (A) whilst Pax6 expression is observed in cells generated from this line that were stably transfected with a Pax6-expression construct (SeyD1-TF1) (B). (C) At Day 14, wild type ES cell-derived cultures contain large numbers of β-III-tubulin-expressing neurons (green; see also Figure 4) with small proportions of GFAP-positive cells (red). (D) At Day 14, almost all SeyD1-TF1 cells (i.e. Pax6^-/- cells containing a Pax6-expression construct) are β-III-tubulin-expressing neurons (contrasting with results from untransfected Pax6^-/- cells at this age, see Figure 4), with a small proportion of GFAP-positive cells.