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.
Pubmed ID: 9256502 RIS Download
Animals | DNA-Binding Proteins | Ear, Inner | Female | Gene Expression Regulation, Developmental | Hair Cells, Vestibular | Mice | Mice, Mutant Strains | Pregnancy | Transcription Factor Brn-3 | Transcription Factor Brn-3A | Transcription Factor Brn-3B | Transcription Factor Brn-3C | Transcription Factors