Mogensen M M, Henderson C G, Mackie J B, Lane E B, Garrod D R, Tucker J B
School of Biomedical Sciences, University of St. Andrews, Scotland, UK.
Cell Motil Cytoskeleton. 1998;41(2):138-53. doi: 10.1002/(SICI)1097-0169(1998)41:2<138::AID-CM5>3.0.CO;2-A.
The intricate and spatially precise ways in which keratin intermediate filaments are deployed in certain cochlear epithelial cells, called supporting cells, suggests that these filaments make a micromechanically important contribution to the functional design of the guinea pig organ of Corti. Filament arrays that include keratins 8, 18, and 19 are confined mainly to regions close to the ends of large transcellular microtubule bundles in supporting cells. These cells and their microtubule bundles link sensory hair cells to a specialized basement membrane that vibrates during hearing. The keratin filament arrays apparently help anchor the ends of the microtubule bundles to cell surfaces. Filaments are concentrated at the apices and bases of most cells that contact hair cells. Substantial arrays of adherens junctions link the apices of these cells. Hence, keratin filaments may contribute to a cytoskeletal network that distributes mechanical forces from cell to cell and that coordinates the displacement of neighboring hair cells. However, high concentrations of keratin filaments have not been detected at the apices of one of the supporting cell types, which apparently has a mechanical role that is different from that of the others. Transmission electron microscopy has revealed previously undescribed filament networks at all the locations where the binding of antibodies to keratins is most marked. There is evidence that intercellular linkage of the keratin networks via their association with actin-containing meshworks and adherens junctions is more extensive than linkage provided by desmosomes.
角蛋白中间丝在某些被称为支持细胞的耳蜗上皮细胞中以复杂且空间精确的方式分布，这表明这些细丝对豚鼠柯蒂氏器的功能设计在微观力学方面具有重要贡献。包含角蛋白8、18和19的丝阵列主要局限于支持细胞中大的跨细胞微管束末端附近的区域。这些细胞及其微管束将感觉毛细胞连接到在听觉过程中振动的特殊基底膜。角蛋白丝阵列显然有助于将微管束的末端锚定到细胞表面。细丝集中在大多数与毛细胞接触的细胞的顶端和基部。大量的黏着连接连接着这些细胞的顶端。因此，角蛋白丝可能有助于形成一个细胞骨架网络，该网络在细胞间分布机械力并协调相邻毛细胞的位移。然而，在其中一种支持细胞类型的顶端未检测到高浓度的角蛋白丝，这种细胞显然具有与其他细胞不同的机械作用。透射电子显微镜在抗体与角蛋白结合最明显的所有位置都揭示了以前未描述的丝网络。有证据表明，角蛋白网络通过与含肌动蛋白的网络和黏着连接的关联而形成的细胞间连接比桥粒提供的连接更广泛。
