[The role of intermediate filaments in forming cellular processes induced in fibroblasts by the tumor promoter TPA].

A tumor promoter phorbol 12-myristate 13-acetate (PMA) induces characteristic reversible changes in the cell shape in certain fibroblastic lines. This reaction to PMA may be regarded as a prototype of reorganizations involving formation of stable cytoplasmic processes. Two specific drugs, Taxol and Colcemid, were used to study the role of microtubules and vimentin-containing intermediate filaments (IF) in the development of PMA-induced reorganizations.

[Role of the cytoskeleton in the morphological normalization of transformed cells in culture].

The role of the cytoskeleton in morphological normalization of transformed cells was studied. Mouse cells of the L197/6 clonal line were fused by polyethylene glycol and replated. The multinuclear cells were more spread than control ones: the ratio of the cell-occupied area to the number of the nuclei increased 2-3 times as a result of multinucleation.

[Regulating role of the microtubule system in the distribution of actin microfilament bundles in embryonic fibroblasts].

The effect of colcemid on the distribution of actin microfilament bundles in the mouse embryo fibroblasts was studied using immunomorphological methods. In the control fibroblasts, microfilament bundles usually cross the entire cell and are oriented in parallel to the stable edges of the cell. In the colcemid-treated cells there are several groups of bundles.

[Changes in the morphology and cytoskeleton of cultured fibroblasts as a result of raised osmotic pressure].

The effect of high osmotic pressure on the morphology and organization of the cytoskeleton and cell-to-substrate contacts of normal mouse embryonic fibroblasts was studied. One-hour incubation of the cells in a hypertonic medium made by the addition of 0.25 M or 0.