Cytokeratin filament organization in the ciliated cells of the quail oviduct.

With the exception of keratinocytes and some types of cultured cells, ciliated cells appear to be the major cell type which contains the most developed cytokeratin meshwork. We report, here, on the intermediate filament (IF) organization in ciliated cells of the quail oviduct using ultrastructural and immunocytochemical techniques. Special attention was focused on the relationships between IF and other cell organelles. The meshwork of IFs appears as a subapical disk constituted of separate bundles mainly composed of interwoven 10-nm filaments. From this subapical region, a descending bundle connects the array of IFs occupying the basal part of the cell. The nucleus is maintained in a loose network of IFs. In ciliated cells there are no free centrioles, but IFs are related to centriolar appendages (striated rootlets).