Winged helix transcription factor BF-1 is essential for the development of the cerebral hemispheres

First Author: Shouhong Xuan (More authors)
Journal: Neuron
Year: 1995

A mouse lacking Foxg1 expression was generated by replacing the coding sequencing with a lacZ/neomycin cassette; heterozygotes (only one copy of Foxg1 absent) were fertile and indistinguishable from wild-type littermates. Homozygotes were live born, but flaccid, with minimal spontaneous movements, and died shortly after birth.

Homozygotes were noted to have a significant reduction in brain size. The ventral telencephalon was noted to be more severely affected than the dorsal telencephalon; almost all telencephalon examined at E12.5 expressed dorsal markers, and not ventral markers. The authors further demonstrate that at E10.5, only dorsal telencephalic neuroepithelial cells are actively proliferating – ventral telencephalon cells are not. Authors suggest that their data demonstrate that absence of Foxg1 results in early withdrawal of telencephalic NPCs from the cell cycle, and premature onset of neuronal differentiation.

Significance
First Foxg1 animal model published; associated differences in brain development well-documented in the homozygous state.