Foxg1 is required for proper separation and formation of sensory cristae during inner ear development.
The vestibular portion of the inner ear, the three semicircular canals and their sensory cristae, is responsible for detecting angular head movements. It was proposed that sensory cristae induce formation of their non-sensory components, the semicircular canals. Here, we analyzed the inner ears of Foxg1(-/-) mouse mutants, which display vestibular defects that are in conflict with the above model. In Foxg1(-/-) ears, the lateral canal is present without the lateral ampulla, which houses the lateral crista. Our gene expression analyses indicate that at the time when canal specification is thought to occur, the prospective lateral crista is present, which could have induced lateral canal formation prior to its demise. Our genetic fate-mapping analyses indicate an improper separation between anterior and lateral cristae in Foxg1(-/-) mutants. Our data further suggest that a function of Foxg1 in the inner ear is to restrict sensory fate.
Hwang
Chan Ho
CH
Lab of Molecular Biology, National Institute on Deafness and Other Communication Disorders, Rockville, Maryland 20850, USA.
Simeone
Antonio
A
Lai
Eseng
E
Wu
Doris K
DK
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000378:metabolism*; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology; D018398:Homeodomain Proteins / Q000378:metabolism*; D060588:LIM Domain Proteins; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009024:Morphogenesis; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D054776:Semicircular Ducts / Q000033:anatomy & histology / Q000196:embryology* / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*
D048868:Adaptor Proteins, Signal Transducing; D055396:Bone Morphogenetic Protein 2; C501120:Dlx5 protein, mouse; D051858:Forkhead Transcription Factors; C489565:Foxg1 protein, mouse; D018398:Homeodomain Proteins; D060588:LIM Domain Proteins; C491976:Lmo4 protein, mouse; D009419:Nerve Tissue Proteins; D014157:Transcription Factors