Essential role of POU-domain factor Brn-3c in auditory and vestibular hair cell development.
The Brn-3 subfamily of POU-domain transcription factor genes consists of three highly homologous members-Brn-3a, Brn-3b, and Brn-3c-that are expressed in sensory neurons and in a small number of brainstem nuclei. This paper describes the role of Brn-3c in auditory and vestibular system development. In the inner ear, the Brn-3c protein is found only in auditory and vestibular hair cells, and the Brn-3a and Brn-3b proteins are found only in subsets of spiral and vestibular ganglion neurons. Mice carrying a targeted deletion of the Brn-3c gene are deaf and have impaired balance. These defects reflect a complete loss of auditory and vestibular hair cells during the late embryonic and early postnatal period and a secondary loss of spiral and vestibular ganglion neurons. Together with earlier work demonstrating a loss of trigeminal ganglion neurons and retinal ganglion cells in mice carrying targeted disruptions in the Brn-3a and Brn-3b genes, respectively, the Brn-3c phenotype reported here demonstrates that each of the Brn-3 genes plays distinctive roles in the somatosensory, visual, and auditory/vestibular systems.
Xiang
M
M
Center for Advanced Biotechnology and Medicine, Department of Pediatrics, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
Gan
L
L
Li
D
D
Chen
Z Y
ZY
Zhou
L
L
O'Malley
B W
BW
Klein
W
W
Nathans
J
J
D000818:Animals; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D007758:Ear, Inner / Q000196:embryology* / Q000378:metabolism; D005260:Female; D018507:Gene Expression Regulation, Developmental; D018069:Hair Cells, Vestibular / Q000196:embryology* / Q000378:metabolism; D051379:Mice; D008817:Mice, Mutant Strains; D011247:Pregnancy; D050818:Transcription Factor Brn-3; D050819:Transcription Factor Brn-3A; D050820:Transcription Factor Brn-3B; D050821:Transcription Factor Brn-3C; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D004268:DNA-Binding Proteins; C494189:Pou4f1 protein, mouse; D050818:Transcription Factor Brn-3; D050819:Transcription Factor Brn-3A; D050820:Transcription Factor Brn-3B; D050821:Transcription Factor Brn-3C; D014157:Transcription Factors