Pax6 and Gli3 are dorsally expressed genes that are known to antagonize sonic hedgehog (Shh) activity. We have previously shown that dorsoventral patterning defects seen in Shh -/- mutants are rescued in Shh -/-;Gli3 -/- compound mutants. Here we investigate if the loss of Pax6 can also ameliorate defects seen in Shh -/- mutants. In support of this notion, we observe that the fusion of the cerebral vesicles seen in Shh -/- mutants is partially corrected in E12.5 Shh -/-;Pax6 -/- compound mutants. Investigation of pan-ventral markers such as Dlx2 also shows that, unlike Shh -/-, a broad domain of expression of this gene is observed in Shh -/-;Pax6 -/- mice. Interestingly, we observe that while the expression of ER81 in the ventral telencephalon is expanded, the expression of Ebf1 is lost. This suggests that the rescued ventral domain observed in Shh -/-;Pax6 -/- mice is the dorsal lateral ganglionic eminence region. With regard to dorsal telencephalic patterning, we also observe rescue of the pallial-subpallial boundary, as well as a partial rescue of the dorsal midline. Together, our findings are consistent with Pax6 function being required for aspects of Gli3-mediated telencephalic patterning.
- Dorsoventral patterning
ASJC Scopus subject areas
- Cognitive Neuroscience
- Cellular and Molecular Neuroscience