Microtubules Microtubule-based cytoskeleton

The Locomotion of Amoeba The Locomotion of Fibroblastic Cell Types The Locomotion of Leukocytes The Behavior of Locomoting Cells The Role of the Cytoskeleton in Cell Locomotion The Microtubule-Based Cytoskeleton The Intermediate Filament-Based Cytoskeleton The Microfilament-Based Cytoskeleton The Organization of Microfilaments in Cells Microfilament Dynamics and Cell Locomotion Sites of Lamellar Protrusion May Be Determined by the Nucleation of Actin Polymerization... 

The Role of Myosins in Cell Locomotion The Role of Actin-Binding Proteins in Cell Locomotion The Transduction of Extracellular Motility Signals to the Cytoskeleton Lipid Flow and Cell Locomotion The Role of Cell Locomotion in Metastasis Intracellular Motility Microtubule-Based Intracellular Motility... 

The cytoplasm of eukaryotic cells is traversed by three-dimensional scaffolding structures consisting of filaments (long protein fibers), which together form the cytoskeleton. These filaments are divided into three groups, based on their diameters microfilaments (6-8 nm), intermediate filaments (ca. 10 nm), and microtubules (ca. 25 nm). All of these filaments are polymers assembled from protein components. 

We conclude that dynamic instability is a means of creating an endless stream of cell types with only one common structure and with the choice of a few anchoring molecules. But this is possible only because there is no necessary relationship between the common structure of the cytoskeleton and the cellular structures that the cytoskeleton is working on. The anchoring molecules (or accessory proteins) are true adaptors that perform two independent recognition processes microtubules on one side and different cellular structures on the other side. The resulting correspondence is based therefore on arbitrary rules, on true natural conventions that we can refer to as the cytoskeleton codes. 

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