Cell locomotion myosins

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... 

Cell migration and cytoplasmic movement involve predominantly actin filaments in the locomotion of neutrophilic granulocytes, both actin filaments and microtubules in the elongation of neuronal growth cones and migration of neurites, and both actin and myosin in cytokinesis and the contraction of skeletal and cardiac muscle. 

Kolega, J., Taylor, D.L. (1993). Gradients in the concentration and assembly of myosin II in living fibroblasts during locomotion and fiber transport. Mol. Biol. Cell 4, 819-836. 

In the cells of this tissue, which are known as fibres, the two major proteins, actin and myosin, are orgaiused to form myofibrils. These are structural rods that can contract (Figure 1.11). This enables muscle cells to shorten, which provides for movement and locomotion (Figure 1.12). There are three types ... 

The work that follows pertains primarily to actin networks. Many proteins within a cell are known to associate with actin. Among these are molecules which can initiate or terminate polymerization, intercalate with and cut chains, crosslink or bundle filaments, or induce network contraction (i.e., myosin) (A,11,12). The central concern of this paper is an exploration of the way that such molecular species interact to form complex networks. Ultimately we wish to elucidate the biophysical linkages between molecular properties and cellular function (like locomotion and shape differentiation) in which cytoskeletal structures are essential attributes. Here, however, we examine the iri vitro formation of cytoplasmic gels, with an emphasis on delineating quantitative assays for network constituents. Specific attention is given to gel volume assays, determinations of gelation times, and elasticity measurements. 

There is an important difference between the macroscopic actin/myosin structure in muscle cells discussed above and the separate actin/myosin threads involved in the locomotion of individual cells. This form of myosin (myosin I) is also quite different, with one head instead of two as in muscle cells (myosin II), further it lacks a tail. Another interesting property of myosin I is its membrane... 

The 20-amino acid residue peptide RS-20, whose sequence derives from smooth muscle myosin light chain kinase (MLCK), is a well-known calmodulin binding peptide [144], Both, RS-20 and LMS-1, a 13-residue peptide derived from the autoinhibitory domain of MLCK, have the capability of inhibiting MLCK phosphorylation activity, normally directed toward the molecular motor, actin binding protein myosin II, which is involved in physiological phenomena like cell polarization and locomotion [145, 146]. 

Kolega, J. (1997). Asymmetry in the distribution of free versus cytoskeletal myosin II in locomoting microcapillary endothelial cells. Exp. Cell Res. 231, 66-82. Kreis, T.E. and Birchmeier, W. (1980). Stress fiber sarcomeres of fibroblasts are contractile. Cell 22, 555-561. 

Urwyler, N., Eggli. P. and KeUer, H.U. (2000). Effects of the myosin inhibitor 2,3-butanedione monoxime (BDM) on ceU shape, locomotion and fluid pinocytosis in human polymorphonuclear leukocytes. Cell Biol. Inti. 24, 863-870. 

Valerius, N.H., Stendahl, O., Hartwig, J.H. and Stossel, TP. (1981). Distribution of actin-binding protein and myosin in polymorphonuclear leukocytes during locomotion and phagocytosis. Cell 24, 195-202. 

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