Occluding junctions and cytoskeletal components in a cultured transporting epithelium

作者：I Meza, Guillermo S. Romano Ibarra, Myrna Sabanero, Adolfo Martínez‐Palomo, Marcelino Cereijido · 发表于：The Journal of Cell Biology · 年份：1980 · DOI：10.1083/jcb.87.3.746 · 被引用次数：327 · 研究领域：3D Printing in Biomedical Research、Barrier Structure and Function Studies、Microtubule and mitosis dynamics

MDCK cells form uninterrupted monolayers and make occluding junctions similar to those of natural epithelia. This aricle explores the relationship between these junctions and the cytoskeleton by combining studies on the distribution of microfilaments and microtubules with the effect of drugs, such as colchicines and cytochalasin B, on the degree of tightness of the occluding junctions. To study the degree of tightness, monolayers were prepared by plating MDCK cells on mylon disks coated with collagen. Disks were mounted as flat sheets between two Lucite chambers, and the sealing capacity of the junctions was evaluated by measuring the electrical resistance across the monolayers. Equivalent monolayers on coverslips were used to study the distribution of microtubules and microfilaments by indirect immunofluorescence staining with antibodies against tubulin and actin. This was done both on complete cells and on cytoskeleton preparations in which the cell membranes had been solubilized before fixation. Staining with antiactin shows a reticular pattern of very fine filaments that spread radially toward the periphery where they form a continuous cortical ring underlying the plasma membrane. Staining with antitubulin depicts fibers that extend radially to form a network that occupies the cytoplasm up to the edges of the cell. Colchicine causes a profound disruption of microtubules but only a 27 percent decrease in the electrical resistance of the resting monolayers. Cytochalasin B, ...