EDInfo Biomedical Sciences Maciver Lab. Home ABP  A-Z Encyclopaedia Amoebae Protist Links Cytoskeleton Links Site Index

Myosin I

Updated 6/4/03

The simplest member of the myosins consisting as it does of the basic myosin head with a "tail" region that is in some types very small. The nomenclature for the myosin I class has been uncoordinated leading to confusion.  An attempt has been made to rectify this situation however (Gillespie et al, 2001).  The myosin I family has been divided into four groups (Berg et al, 2001).
The tails of myosin I class are very variable, some contain membrane binding domains while others contain an ATP-insensitive actin binding site
The function of myosin I is most often described as being vesicle transport (Adams & Pollard, 1986), but to date the clearest example of a myosin I function comes from experiments with Acanthamoeba in which antibodies against myosin Ic were introduced to the cytoplasm that resulted from the cell exploding through the disruption of the contractile vacuole (Doberstein et al, 1993).



Adams, R. J. & Pollard, T. D. (1986) Propulsion of organelles isolated from Acanthamoeba along actin filaments by myosin-1. Nature. 322, 754-756.

Baines, I. C., Brzeska, H. & Korn, E. D. (1992) Differential localization of Acanthamoeba myosin I isoforms. J.Cell Biol. 119, 1193-1203.

Berg, J. S., Powell, B. C. & Cheney, R. E. (2001) A millennial myosin census. Mol.Biol.Cell. 12, 780-794.

Brzeska, H., Szczepanowska, J., Hoey, J. & Korn, E. D. (1996) The catalytic domain of Acanthamoeba myosin I heavy chain kinase. J.Biol.Chem. 271, 27056-27062.

Brzeska, H., Young, R., Tan, C., Szczepanowska, J. & Korn, E. D. (2001) Calmodulin-binding and autoinhibitory domains of Acanthamoeba myosin I heavy chain kinase, a p21-activated kinase (PAK). J.Biol.Chem. 276, 47468-47473.

Carragher, B. O., Cheng, N., Wang, Z.-Y., Korn, E. D., Reilein, A., Belnap, D. M., Hammer III, J. A. & Steven, A. C. (1998) Structural invariance of constitutively active and inactive mutants of Acanthamoeba myosin IC bound to F-actin in the rigor state. Proc.Nat.Acad.Sci. USA. 95, 15206-15211.

Coluccio, L. M. & Geeves, M. A. (1999) Transient kinetic analysis of the 130-kDa myosin I (MYR-1 gene product) from rat liver.  J.Biol.Chem. 274, 21575-21580.

Cordonnier, M.-N., Dauzonne, D., Louvard, D. & Coudrier, E. (2001) Actin filaments and myosin I alpha cooperate with microtubules for the movement of lysosomes. Mol.Biol. Cell. 12, 4013-4029.

Dai, J., Ting-Beall, H. P., Hochmuth, R. M., Sheetz, H. P. & Titus, M. A. (1999) Myosin 1 contributes to the generation of resting cortical tension.  J.Biophys. 77, 1168-1176.

de La Roche, M. A. & Cote, G. P. (2001) Regulation of Dictyostelium myosin I and II. Biochim.Biophys.Acta. 1525, 245-261.

Doberstein, S. K., Baines, I. C., Wiegand, G., Korn, E. D. & Pollard, T. D. (1993) Inhibition of contractile vacuole function in vivo by antibodies against myosin-I. Nature. 365, 841-843.

Ezzell, R. M., Leung, J., Collins, K., Chafel, M. M., Cardozo, T. J. & Matsudaira, P. T. (1992) Expression and Localization of Villin, Fimbrin, and Myosin I in Differentiating Mouse F9 Teratocarcinoma Cells. Developmental Biol. 151, 575-585.

Fukui, Y., Lynch, T. J., Brzeska, H. & Korn, E. D. (1989) Myosin is located at the leading edge of locomoting Dictyostelium amoebae. Nature. 341, 328-332.

Gillespie, P.G., Albanesi, J.P., Bahler, M., Bement, W.M., Berg, J.S.,et al (2001) Myosin-1 nomenclature. J.Cell Biol. 155, (5), 703-704.

Gliksman, N. R., Santoyo, G., Novak, K. D. & Titus, M. A. (2001) Myosin I phosphorylation is increased by chemotactic stimulation. J.Biol.Chem. 276, 5235-5239.

Heimann, K., Percival, J. M., Weinberger, R., Gunning, P. & Stow, J. L. (1999) Specific isoforms of actin-binding proteins on distinct populations of golgi-derived vesicles. J.Biol.Chem. 274, 10743-10750.

Jontes, J. D. & Milligan, R. A. (1997) Brush border myosin-I structure and ADP-dependent conformational changes revealed by cryoelectron microscopy and image analysis, J.Cell Biol. 139, 683-693.

Kollmar, M., Dürrwang, U., Kliche, W., Manstein, D. J. & Kull, F. J. (2002) Crystal structure of the motor domain of a class-I myosin. EMBO J. 21, 2517-2525.

Lee, W.-L., Ostrap, M., Zot, H. G. & Pollard, T. D. (1999) Organization and ligand binding properties of the tail of Acanthamoeba myosin-IA. J.Biol.Chem. 274, 35159-35171.

Morita, Y. S., Jung, G., Hammer III, J. A. & Fukui, Y. (1996) Localization of Dictyostelium myoB and myoD to filopodia and cell-cell contact sites using isoform-specific antibodies. Eur.J.Cell Biol. 71, 371-379.

Novak, K. D., Peterson, M. D., Reedy, M. C. & Titus, M. A. (1995) Dictyostelium myosin I double mutants exhibit conditional defects in pinocytosis. J.Cell Biol. 131, 1205-1221.

Nowak, G., Pestic-Dragovich, L., Hozák, P., Philimonenko, A., Simerly, C., Schatten, G. & de Lanerolle, P. (1997) Evidence for the presence of Myosin I in the nucleus. J.Biol.Chem. 272, 17176-17181.

Ostrap, E. M., Lin, T., Rosenfeld, S. S. & Tang, N. (2002) Mechanism of regulation of Acanthamoeba myosin -IC by heavy-chain phosphorylation., Biochemistry. 41, 12450-12456.

Pelham, R. J., Lin, J. J.-C. & Wang, Y. L. (1996) A high molecular mass non-muscle tropomyosin isoform stimulates retrograde organelle transport. J.Cell Sci. 109, 981-989.

Probst, F. J., Fridell, R. A., Raphael, Y., Saunders, T. L., Wang, A., Liang, Y., Morell, R. J., Touchman, J. W., Lyons, R. H., Noben-Trauth, K., Friedman, T. B. & Camper, S. A. (1998) Correction of deafness in shaker-2 mice by an unconventional myosin in a BAC transgene, Science. 280, 1444-1447.

Schwarz, E. C., Nuehaus, E. M., Kistler, C., Henkel, A. W. & Soldati, T. (2000) Dictyostelium myosin IK is involved in the maintenance of cortical tension and affects motility and phagocytosis., J.Cell Sci. 113, 621-633.

Senda, S., Lee, S.-F., Cote, G. P. & Titus, M. A. (2001) Recruitment of a specific amoeboid myosin I isoform to the plasma membrane in chemotactic Dictyostelium cells. J.Biol. Chem. 267, 2898-2904.

Skowron, J. F., Bement, W. M. & Mooseker, M. S. (1998) Human brush border myosin-1 and myosin-1c expression in human intestine and Caca-2BBe cells. Cell Mot. Cytoskeleton. 41, 308-324.

Wang, Z.-Y., Wang, F., Sellers, J. R., Korn, E. D. & Hammer III, J. A. (1998) Analysis of the regulatory phosphorylation site in Acanthamoeba myosin IC by using site-directed mutagenesis. Proc.Nat.Acad.Sci. USA. 95, 15200-15205.

Yazu, M., Adachi, H. & Sutoh, K. (1999) Novel Dictyostelium unconventional myosin MyoK is a class I myosin with the longest loop-1 insert and the shortest tail. Biochem.Biophys.Res.Comm. 255, 711-716.

  EDInfo Biomedical Sciences Cytoskeletal Links Encyclopaedia of A.B.P.s The Amoebae Protozoology links Glossary of Amoeba terms   Maciver Lab Home