Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA.
PLoS Biol. 2012 Jan;10(1):e1001231. doi: 10.1371/journal.pbio.1001231. Epub 2012 Jan 3.
A large proportion of age-related hearing loss is caused by loss or damage to outer hair cells in the organ of Corti. The organ of Corti is the mechanosensory transducing apparatus in the inner ear and is composed of inner hair cells, outer hair cells, and highly specialized supporting cells. The mechanisms that regulate differentiation of inner and outer hair cells are not known. Here we report that fibroblast growth factor 20 (FGF20) is required for differentiation of cells in the lateral cochlear compartment (outer hair and supporting cells) within the organ of Corti during a specific developmental time. In the absence of FGF20, mice are deaf and lateral compartment cells remain undifferentiated, postmitotic, and unresponsive to Notch-dependent lateral inhibition. These studies identify developmentally distinct medial (inner hair and supporting cells) and lateral compartments in the developing organ of Corti. The viability and hearing loss in Fgf20 knockout mice suggest that FGF20 may also be a deafness-associated gene in humans.
很大一部分与年龄相关的听力损失是由于耳蜗器官中外毛细胞的损失或损伤引起的。耳蜗器官是内耳的机械感觉换能器，由内毛细胞、外毛细胞和高度特化的支持细胞组成。调节内毛细胞和外毛细胞分化的机制尚不清楚。在这里，我们报告说，成纤维细胞生长因子 20（FGF20）是耳蜗器官中外侧耳蜗隔（外毛细胞和支持细胞）细胞在特定发育时间分化所必需的。在没有 FGF20 的情况下，小鼠耳聋，外侧隔细胞保持未分化、有丝分裂后和对 Notch 依赖性侧向抑制无反应。这些研究确定了发育中的耳蜗器官中具有发育上不同的内侧（内毛细胞和支持细胞）和外侧隔室。Fgf20 基因敲除小鼠的存活和听力损失表明，FGF20 也可能是人类耳聋相关基因。
