Preferences help
enabled [disable] Abstract
Number of results
2002 | 49 | 4 | 805-812
Article title

Structural determinants of cooperativity in acto-myosin interactions.

Title variants
Languages of publication
Regulation of muscle contraction is a very cooperative process. The presence of tropomyosin on the thin filament is both necessary and sufficient for cooperativity to occur. Data recently obtained with various tropomyosin isoforms and mutants help us to understand better the structural requirements in the thin filament for cooperative protein interactions. Forming an end-to-end overlap between neighboring tropomyosin molecules is not necessary for the cooperativity of the thin filament activation. When direct contacts between tropomyosin molecules are disrupted, the conformational changes in the filament are most probably transmitted cooperatively through actin subunits, although the exact nature of these changes is not known. The function of tropomyosin ends, alternatively expressed in various isoforms, is to confer specific actin affinity. Tropomyosin's affinity or actin is directly related to the size of the apparent cooperative unit defined as the number of actin subunits turned into the active state by binding of one myosin head. Inner sequences of tropomyosin, particularly actin-binding periods 3 to 5, play crucial role in myosin-induced activation of the thin filament. A plausible mechanism of tropomyosin function in this process is that inner tropomyosin regions are either specifically recognized by myosin or they define the right actin conformation required for tropomyosin movement from its blocking position.
Physical description
  • Kazimierz Wielki University of Bydgoszcz, Institute of Biology and Environmental Protection, Bydgoszcz, and Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warszawa, Poland
  • Brown JH, Kim K-H, Jun G, Greenfield NJ, Dominguez R, Volkmann N, Hitchock- DeGregori SE, Cohen C. (2001) Deciphering the design of the tropomyosin molecule. Proc Natl Acad Sci U S A.; 98: 8496-501.
  • Butters CA, Willadsen KA, Tobacman LS. (1993) Cooperative interactions between adjacent troponin-tropomyosin complexes may be transmitted through the actin filament. J Biol Chem.; 268: 15565-70.
  • Cho YJ, Liu J, Hitchcock-DeGregori SE. (1990) The amino terminus of muscle tropomyosin is a major determinant for function. J Biol Chem.; 265: 538-45.
  • Craig R, Lehman W. (2001) Crossbridge and tropomyosin positions observed in native, interacting thick and thin filaments. J Mol Biol.; 311: 1027-36.
  • Drees B, Brown C, Barrel BG, Bretscher A. (1995) Tropomyosin is essential in yeast; yet the TPM1 and TPM2 products perform distinct functions. J Cell Biol.; 128: 383-92.
  • Dabrowska R, Nowak E, Drabikowski W. (1983) Some functional properties of nonpolymerizable and polymerizable tropomyosin. J Muscle Res Cell Motil.; 4: 143-61.
  • Eaton BL. (1976) Tropomyosin binding to F-actin induced by myosin heads. Science.; 192: 1337-9.
  • Geeves MA, Lehrer SS. (1994) Dynamics of the muscle thin filament regulatory switch: the size of the cooperative unit. Biophys J.; 67: 273-82.
  • Gordon AM, Homsher E, Regnier M. (2000) Regulation of contraction in striated muscle. Physiol Rev.; 80: 853-924.
  • Hammell RL, Hitchcock-DeGregori SE. (1996) Mapping the functional domains within the carboxyl terminus of alpha-tropomyosin encoded by the alternatively spliced ninth exon. J Biol Chem.; 271: 4236-42.
  • Hill TL, Eisenberg E, Greene L. (1980) Theoretical model for the cooperative equilibrium binding of myosin subfragment-1 to the actin-troponin-tropomyosin complex. Proc Natl Acad Sci U S A.; 77: 3186-90.
  • Hitchcock-DeGregori SE, Song Y, Moraczewska J. (2001) Importance of internal regions and the overall length of tropomyosin for actin binding and regulatory function. Biochemistry.; 40: 2104-12.
  • Landis CA, Back N, Homsher E, Tobacman L. (1999) Effects of tropomyosin internal deletions on thin filament function. J Biol Chem.; 274: 31279-85.
  • Lees-Miller JP, Helfman DM. (1991) The molecular basis for tropomyosin isoform diversity. Bioessays.; 13: 429-37.
  • Lehman W, Craig R, Vibert P. (1994) Ca2+-induced tropomyosin movement in Limulus thin filaments revealed by three-dimentional reconstruction. Nature.; 368: 65-7.
  • Lehman W, Hatch V, Korman N, Rosol M, Thomas L, Maytum R, Geeves MA, Van Eyk JE, Tobacman L, Craig R. (2000) Tropomyosin and actin isoforms modulate the localization of tropomyosin strands on actin filament. J Mol Biol.; 302: 593-606.
  • Lehrer SS, Golitsina NL, Geeves MA. (1997) Actin-tropomyosin activation of myosin subfragment 1 ATPase and thin filament cooperativity. The role of tropomyosin flexibility and end-to-end interactions. Biochemistry.; 36: 13449-54.
  • Liu H, Bretscher A. (1989) Disruption of the single tropomyosin gene in yeast results in the disappearance of actin cables from the cytoskeleton. Cell.; 57: 233-42.
  • McKillop DF, Geeves MA. (1993) Regulation of the interaction between actin and myosin subfragment 1: evidence for three states of the thin filament. Biophys J.; 65: 693-701.
  • McLachlan AD, Stewart M. (1975) Tropomyosin coiled-coil interactions: evidence for an unstaggered structure. J Mol Biol.; 98: 293-304.
  • McLachlan AD, Stewart M. (1976) The 14-fold periodicity in a-tropomyosin and the interaction with actin. J Mol Biol.; 103: 271-98.
  • Milligan RA, Wittaker M, Safer D. (1990) Molecular structure of F-actin and location of surface binding sites. Nature.; 348: 217-21.
  • Moraczewska J, Hitchcock-DeGregori SE. (2000) Independent functions for N- and C-termini in the overlap region of tropomyosin. Biochemistry.; 39: 6891-7.
  • Moraczewska J, Nicholson-Flynn K, Hitchcock-DeGregori SE. (1999) The ends of tropomyosin are major determinants of actin affinity and myosin subfragment1-induced binding to F-actin in the open state. Biochemistry.; 38: 15885-92.
  • O'Brien EJ, Bennett PM, Hanson J. (1971) Optical diffraction studies of myofibrillar structure. Philos Trans R Soc Lond B Biol Sci.; 261: 201-8.
  • Pan B-S, Gordon AM, Luo Z. (1989) Removal of tropomyosin overlap modifies cooperative binding of myosin S-1 to reconstituted thin filaments of rabbit striated muscle. J Biol Chem.; 264: 8495-8.
  • Perry SV. (2001) Vertebrate tropomyosin: distribution, properties and function. J Muscle Res Cell Motil.; 22: 5-49.
  • Phillips GN Jr, Fillers JP, Cohen C. (1986) Tropomyosin crystal structure and muscle regulation. J Mol Biol.; 192: 111-31.
  • Pittenger MF, Kazzaz JA, Helfman DM. (1994) Functional properties of non-muscle tropomyosin isoforms. Curr Opin Cell Biol.; 6: 96-104.
  • Poole KVG, Evans G, Rosenbaum G, Lorenz M, Holmes KC. (1995) The effect of cross-bridges on the calcium sensitivity of the structural change of the regulated thin filament. Biophys J.; 68: 365a.
  • Rosol M, Lehman W, Craig R, Landis CA, Butters CA, Tobacman L. (2000) Three-dimensional reconstruction of thin filaments containing mutant tropomyosin. Biophys J.; 78: 908-17.
  • Sellers JR, Adelstein RS. (1986) Regulation of contractile activity. In The Enzymes. Boyer PD, Krebs EG, eds, pp 381-418. Academic Press, Orlando.
  • Tobacman L, Butters CA. (2000) A new model of cooperative myosin-thin filament binding. J Biol Chem.; 275: 27587-93.
  • Tobacman LS. (1996) Thin filament-mediated regulation of cardiac contraction. Annu Rev Physiol.; 58: 447-81.
  • Vibert P, Craig R, Lehman W. (1997) Steric model for activation of muscle thin filaments. J Mol Biol.; 266: 8-14.
  • Xu C, Craig R, Tobacman L, Horowitz R, Lehman W. (1999) Tropomyosin positions in regulated thin filaments revealed by cryoelectron microscopy. Biophys J.; 77: 985-92.
  • Zot AS, Potter JD. (1987) Structural aspects of troponin-tropomyosin regulation of skeletal muscle contraction. Annu Rev Biophys Biophys Chem.; 16: 535-59.
Document Type
Publication order reference
YADDA identifier
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.