Development and properties of stereociliary link types in hair cells of the mouse cochlea
Development and properties of stereociliary link types in hair cells of the mouse cochlea
复制标题
DOI：
10.1002/cne.20513
复制
发表时间：
2005-04-25
影响因子：
2.5
通讯作者：
Richardson, GP
中科院分区：
文献类型：
--
作者：
Goodyear, RJ;Marcotti, W;Richardson, GP
成熟小鼠耳蜗外毛细胞的毛束具有三种不同的细胞表面特化：尖端连接、水平顶部连接和盖膜附着冠。电子显微镜被用来研究这些链接类型的外观和成熟，并检查其他结构与发展中的毛束短暂。在胚胎第17.5天（E17.5），静纤毛通过精细的横向链接相互连接，并在其表面分布有点状元件。在这个阶段也可以看到倾斜的尖端链接。到出生后第2天（P2），外毛细胞束具有致密的细胞被，但在E17.5时失去了许多横向连接。在P2，踝关节连接出现在束的基部周围，在静纤毛尖端可见覆膜附着冠。踝关节连接在P9时变得不那么明显，在P12时完全消失。水平顶部连接器的出现，持续到成年，发生伴随着这种踝关节链接的损失。用钙螯合剂BAPTA或蛋白酶枯草杆菌蛋白酶处理使这些联系能够进一步区分。踝关节连接对两种治疗都敏感，尖端连接仅对BAPTA敏感，并且通过枯草杆菌蛋白酶而不是BAPTA去除覆膜附着冠。细胞涂层材料仅对枯草杆菌蛋白酶部分敏感，而水平顶部连接器抵抗两种治疗。这些结果表明，有一个丰富的，快速变化的阵列不同的链接覆盖发展中的毛束，成为逐步完善，以产生成熟的补充P19。(c)2005 Wiley-Liss，Inc.
The hair bundles of outer hair cells in the mature mouse cochlea possess three distinct cell-surface specializations: tip links, horizontal top connectors, and tectorial membrane attachment crowns. Electron microscopy was used to study the appearance and maturation of these link types and examine additional structures transiently associated with the developing hair bundle. At embryonic day 17.5 (E17.5), the stereocilia are interconnected by fine lateral links and have punctate elements distributed over their surface. Oblique tip links are also seen at this stage. By postnatal day 2 (P2), outer hair cell bundles have a dense cell coat, but have lost many of the lateral links seen at E17.5. At P2, ankle links appear around the base of the bundle and tectorial membrane attachment crowns are seen at the stereociliary tips. Ankle links become less apparent by P9 and are completely lost by P12. The appearance of horizontal top connectors, which persist into adulthood, occurs concomitant with this loss of ankle links. Treatment with the calcium chelator BAPTA or the protease subtilisin enabled these links to be further distinguished. Ankle links are susceptible to both treatments, tip links are only sensitive to BAPTA, and tectorial membrane attachment crowns are removed by subtilisin but not BAPTA. The cell-coat material is partially sensitive to subtilisin alone, while horizontal top connectors resist both treatments. These results indicate there is a rich, rapidly changing array of different links covering the developing hair bundle that becomes progressively refined to generate the mature complement by P19. (c) 2005 Wiley-Liss, Inc.