Tucker J B, Paton C C, Richardson G P, Mogensen M M, Russell I J
School of Biological and Medical Sciences, University of St Andrews, Fife, Scotland.
J Cell Sci. 1992 Jun;102 ( Pt 2):215-26. doi: 10.1242/jcs.102.2.215.
This investigation provides evidence that pericentriolar material is divorced from the immediate vicinities of centrioles and becomes functionally associated with the plasmalemma during the differentiation of a mammalian cell type. Such events occur prior to the assembly of large transcellular microtubule bundles in columnar epithelial cells called inner pillar cells in the mouse organ of Corti. The microtubules do not radiate from a typical centrosome and its centrioles. They elongate from a microtubule-organizing centre (MTOC), which is deployed as a subapical cell surface-associated layer in each cell. Most of the dense material of this layer, and the tops of most of the microtubules, are initially concentrated around the sides of a cell about 1 microns below its apical surface. In addition, a pair of centrioles is located above the layer, which acts as if it is a pericellular concentration of the pericentriolar material of a modified centrosome. Although microtubule nucleation takes place in a centrosome-like region, 13 protofilament fidelity is not exercised. Most of the microtubules have 15 protofilaments. Microtubule assembly progresses in these cells after the organ of Corti has been isolated for in vitro culture. However, large numbers of microtubules elongate from pericentriolar material juxtaposed against the centrioles. Hence, there is some reversion by the centrosomes of cultured cells to the operational configuration regarded as typical for animal tissue cells in general.
本研究提供了证据，表明在一种哺乳动物细胞类型的分化过程中，中心粒周围物质与中心粒的紧邻区域分离，并与质膜建立功能联系。这些事件发生在小鼠柯蒂氏器中称为内柱细胞的柱状上皮细胞内大的跨细胞微管束组装之前。微管并非从典型的中心体及其中心粒辐射而出。它们从一个微管组织中心（MTOC）延伸，该中心在每个细胞中作为亚顶端细胞表面相关层分布。该层的大部分致密物质以及大多数微管的顶端最初集中在细胞顶端表面下方约1微米处的细胞周边。此外，一对中心粒位于该层上方，其作用就好像是一个经过修饰的中心体的中心粒周围物质的细胞周集中区。尽管微管成核发生在类似中心体的区域，但并未保持13根原纤维的精确性。大多数微管有15根原纤维。在柯蒂氏器被分离用于体外培养后，这些细胞中的微管组装仍在进行。然而，大量微管从紧邻中心粒的中心粒周围物质延伸出来。因此，培养细胞的中心体在一定程度上恢复到了一般被认为是动物组织细胞典型的运作构型。
