Fig. 1. Pax6 protein levels are increased in PAX77 mice. (A) Western-blots of E12.5 wild-type, PAX77⁺ and PAX77^+/+ telencephalic-protein extracts with anti-Pax6 and anti-ß-actin antibodies. (B) Quantitation of the two isoforms, 48 kDa Pax6(5a) and 46 kDa Pax6, in E12.5 wild-type PAX77⁺ and PAX77^+/+ telencephalons. For each sample, the intensity of the Pax6 and Pax6(5a) bands was divided by the intensity of the ß-actin band to account for loading differences and values were calculated relative to the mean value for wild-type Pax6, which was assigned a value of 1 (mean±s.e.m. are shown; n=3 in all cases). Asterisks indicate statistically significant differences from wild type (Student's t-test, P<0.05). There was no significant difference between the levels of Pax6 and Pax6(5a) in PAX77^+/+ and PAX77⁺ embryonic brains. (C-E) Immunohistochemistry on sagittal sections through the cortex showing Pax6 expression in (C) wild-type (WT), (D) PAX77⁺ and (E) PAX77^+/+ E12.5 embryos. The rostro-lateral^high to caudo-medial^low gradient of Pax6 expression is conserved in the cortex of PAX77 mice. Scale bar: 200 µm.