Xiang M, Gan L, Li D, Chen Z Y, Zhou L, O'Malley B W, Klein W, Nathans J
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.
Proc Natl Acad Sci U S A. 1997 Aug 19;94(17):9445-50. doi: 10.1073/pnas.94.17.9445.
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.
POU结构域转录因子基因的Brn-3亚家族由三个高度同源的成员组成，即Brn-3a、Brn-3b和Brn-3c，它们在感觉神经元和少数脑干核中表达。本文描述了Brn-3c在听觉和前庭系统发育中的作用。在内耳中，仅在听觉和前庭毛细胞中发现Brn-3c蛋白，而Brn-3a和Brn-3b蛋白仅在螺旋神经节和前庭神经节神经元的亚群中发现。携带Brn-3c基因靶向缺失的小鼠失聪且平衡受损。这些缺陷反映了胚胎后期和出生后早期听觉和前庭毛细胞的完全丧失以及螺旋神经节和前庭神经节神经元的继发性丧失。结合早期的研究工作，分别证明携带Brn-3a和Brn-3b基因靶向破坏的小鼠中三叉神经节神经元和视网膜神经节细胞的丧失，本文报道的Brn-3c表型表明，每个Brn-3基因在躯体感觉、视觉和听觉/前庭系统中发挥着独特的作用。
