title: Removal of Pax6 partially rescues the loss of ventral structures in Shh null mice.
abstract: 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.
authors.affiliation: Developmental Genetics Program and the Department of Cell Biology, The Skirball Institute of Biomolecular Medicine, New York University Medical Center, New York, NY 10016, USA.
authors.forename: Marc
authors.initials: M
authors.lastname: Fuccillo
authors.forename: Michael
authors.initials: M
authors.lastname: Rutlin
authors.forename: Gord
authors.initials: G
authors.lastname: Fishell
mesh_terms: D000818:Animals; D019521:Body Patterning / Q000502:physiology; D002449:Cell Aggregation; D002454:Cell Differentiation; D002465:Cell Movement; D005136:Eye Proteins / Q000378:metabolism*; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins / Q000378:metabolism*; D066298:In Vitro Techniques; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009415:Nerve Net / Q000166:cytology / Q000196:embryology / Q000502:physiology; D009474:Neurons / Q000166:cytology* / Q000502:physiology*; D038081:Organogenesis / Q000502:physiology; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D013687:Telencephalon / Q000166:cytology* / Q000196:embryology* / Q000502:physiology; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: C088334:Distal-less homeobox proteins; D005136:Eye Proteins; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; C000605732:Pax6 protein, mouse; D012097:Repressor Proteins; C465570:Shh protein, mouse; D015534:Trans-Activators; D014157:Transcription Factors