Cell motility

Certain proteins endow cells with unique capabilities for movement. Cell division, muscle contraction, and cell motility represent some of the ways in which cells execute motion. The contractile and motile proteins underlying these motions share a common property they are filamentous or polymerize to form filaments. Examples include actin and myosin, the filamentous proteins forming the contractile systems of cells, and tubulin, the major component of microtubules (the filaments involved in the mitotic spindle of cell division as well as in flagella and cilia). Another class of proteins involved in movement includes dynein and kinesin, so-called motor proteins that drive the movement of vesicles, granules, and organelles along microtubules serving as established cytoskeletal tracks. ... 

Blanchard, A., Ohanian, V., and Critchley, D., 1989. The. structure and fnnction of a-3.c inin. Journal of Muscle Research and Cell Motility 10 280-289. 

Phosphorylation is the reversible process of introducing a phosphate group onto a protein. Phosphorylation occurs on the hydroxyamino acids serine and threonine or on tyrosine residues targeted by Ser/Thr kinases and tyrosine kinases respectively. Dephosphorylation is catalyzed by phosphatases. Phosphorylation is a key mechanism for rapid posttranslational modulation of protein function. It is widely exploited in cellular processes to control various aspects of cell signaling, cell proliferation, cell differentiation, cell survival, cell metabolism, cell motility, and gene transcription. 

Chitoohgomers act as templates for hyaluronan synthesis. Hyaluronan has been shown to promote cell motility, adhesion and prohferation, and... 

It is of interest that proteins termed motility factors (55-70 kD) are secreted by fetal cells and some tumor cells. These proteins act as autocrine factors and stimulate rapid movement by these cells. Motility factors induce the formation of cell processes that are packed with actin filaments and have an increased number of receptors for the matrix proteins laminin and fibronectin. The latter enhance the ability of the cells to bind to the extracellular matrix. Thus, it is likely that motility factors influence the organization of the cytoskeleton through changes taking place at the cell surface (reviewed by Warn and Dowrick, 1989). 

The widespread nature of cell motility is readily apparent, but the attention of this chapter will be focused on phenomena that relate particularly to human medicine in order to accommodate the medical nature of this compendium. 

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Huxley, H.E. (1973). Muscular contraction and cell motility. Nature 243,445-449. 

King, C.A. (1988). Cell motility of sporozoan protozoa. Parasitology Today 4, 315-319. 

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Lassing, I Lindberg, U. (1988). Evidence that the phosphatidyl-inositol cycle is linked to cell motility. Expt. Cell Res. 174, 1-15. 

Stoker, M., Gherardi, E., Perryman, M., Gray, J. (1987). Scatter factor is a fibroblast-derived modulator of epithelial cell motility. Nature, 327,239-242. 

Theriot, J.A., Mitchison, T.J. (1992). The nucleation-release model of actin filament dynamics in cell motility. Trends Cell Biol. 2,219-222. 

King, C.A., Preston, T.M. (1992). Cell Motility. In Fundamentals of Cell Biology, Vol. 5B Membrane Dynamics and Signalling, pp. 145-182. JAI Press Inc, Greenwich. 

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