Abstract
Muscle contraction is highly dynamic and thus may be influenced by viscosity of the medium surrounding the myofilaments. Single, skinned fibers from rabbit psoas muscle were used to test this hypothesis. Viscosity within the myofilament lattice was increased by adding to solutions low molecular weight sugars (disaccharides sucrose or maltose or monosaccharides glucose or fructose). At maximal Ca2+ activation, isometric force (Fi) was inhibited at the highest solute concentrations studied, but this inhibition was not directly related to viscosity. Solutes readily permeated the filament lattice, as fiber diameter was unaffected by added solutes (except for an increased diameter with Fi < 30% of control). In contrast, there was a linear dependence upon 1/viscosity for both unloaded shortening velocity and also the kinetics of isometric tension redevelopment; these effects were unrelated to either variation in solution osmolarity or inhibition of force. All effects of added solute were reversible. Inhibition of both isometric as well as isotonic kinetics demonstrates that viscous resistance to filament sliding was not the predominant factor affected by viscosity. This was corroborated by measurements in relaxed fibers, which showed no significant change in the strain-rate dependence of elastic modulus when viscosity was increased more than twofold. Our results implicate cross-bridge diffusion as a significant limiting factor in cross-bridge kinetics and, more generally, demonstrate that viscosity is a useful probe of actomyosin dynamics.
Full Text
The Full Text of this article is available as a PDF (158.2 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Ansari A., Jones C. M., Henry E. R., Hofrichter J., Eaton W. A. The role of solvent viscosity in the dynamics of protein conformational changes. Science. 1992 Jun 26;256(5065):1796–1798. doi: 10.1126/science.1615323. [DOI] [PubMed] [Google Scholar]
- Ashley C. C., Moisescu D. G. Effect of changing the composition of the bathing solutions upon the isometric tension-pCa relationship in bundles of crustacean myofibrils. J Physiol. 1977 Sep;270(3):627–652. doi: 10.1113/jphysiol.1977.sp011972. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bagni M. A., Cecchi G., Colomo F., Garzella P. Absence of mechanical evidence for attached weakly binding cross-bridges in frog relaxed muscle fibres. J Physiol. 1995 Jan 15;482(Pt 2):391–400. doi: 10.1113/jphysiol.1995.sp020526. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Beece D., Eisenstein L., Frauenfelder H., Good D., Marden M. C., Reinisch L., Reynolds A. H., Sorensen L. B., Yue K. T. Solvent viscosity and protein dynamics. Biochemistry. 1980 Nov 11;19(23):5147–5157. doi: 10.1021/bi00564a001. [DOI] [PubMed] [Google Scholar]
- Brenner B., Chalovich J. M., Greene L. E., Eisenberg E., Schoenberg M. Stiffness of skinned rabbit psoas fibers in MgATP and MgPPi solution. Biophys J. 1986 Oct;50(4):685–691. doi: 10.1016/S0006-3495(86)83509-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brenner B., Eisenberg E. Rate of force generation in muscle: correlation with actomyosin ATPase activity in solution. Proc Natl Acad Sci U S A. 1986 May;83(10):3542–3546. doi: 10.1073/pnas.83.10.3542. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brenner B. Technique for stabilizing the striation pattern in maximally calcium-activated skinned rabbit psoas fibers. Biophys J. 1983 Jan;41(1):99–102. doi: 10.1016/S0006-3495(83)84411-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brenner B., Yu L. C. Equatorial x-ray diffraction from single skinned rabbit psoas fibers at various degrees of activation. Changes in intensities and lattice spacing. Biophys J. 1985 Nov;48(5):829–834. doi: 10.1016/S0006-3495(85)83841-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Burton K., Huxley A. F. Identification of source of oscillations in apparent sarcomere length measured by laser diffraction. Biophys J. 1995 Jun;68(6):2429–2443. doi: 10.1016/S0006-3495(95)80425-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chase P. B., Kushmerick M. J. Effect of physiological ADP concentrations on contraction of single skinned fibers from rabbit fast and slow muscles. Am J Physiol. 1995 Feb;268(2 Pt 1):C480–C489. doi: 10.1152/ajpcell.1995.268.2.C480. [DOI] [PubMed] [Google Scholar]
- Chase P. B., Kushmerick M. J. Effects of pH on contraction of rabbit fast and slow skeletal muscle fibers. Biophys J. 1988 Jun;53(6):935–946. doi: 10.1016/S0006-3495(88)83174-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chase P. B., Martyn D. A., Hannon J. D. Activation dependence and kinetics of force and stiffness inhibition by aluminiofluoride, a slowly dissociating analogue of inorganic phosphate, in chemically skinned fibres from rabbit psoas muscle. J Muscle Res Cell Motil. 1994 Apr;15(2):119–129. doi: 10.1007/BF00130423. [DOI] [PubMed] [Google Scholar]
- Chase P. B., Martyn D. A., Hannon J. D. Isometric force redevelopment of skinned muscle fibers from rabbit activated with and without Ca2+. Biophys J. 1994 Nov;67(5):1994–2001. doi: 10.1016/S0006-3495(94)80682-4. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chase P. B., Martyn D. A., Kushmerick M. J., Gordon A. M. Effects of inorganic phosphate analogues on stiffness and unloaded shortening of skinned muscle fibres from rabbit. J Physiol. 1993 Jan;460:231–246. doi: 10.1113/jphysiol.1993.sp019469. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cooke R. The actomyosin engine. FASEB J. 1995 May;9(8):636–642. doi: 10.1096/fasebj.9.8.7768355. [DOI] [PubMed] [Google Scholar]
- Edman K. A. The velocity of unloaded shortening and its relation to sarcomere length and isometric force in vertebrate muscle fibres. J Physiol. 1979 Jun;291:143–159. doi: 10.1113/jphysiol.1979.sp012804. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Finer J. T., Simmons R. M., Spudich J. A. Single myosin molecule mechanics: piconewton forces and nanometre steps. Nature. 1994 Mar 10;368(6467):113–119. doi: 10.1038/368113a0. [DOI] [PubMed] [Google Scholar]
- Fisher A. J., Smith C. A., Thoden J. B., Smith R., Sutoh K., Holden H. M., Rayment I. X-ray structures of the myosin motor domain of Dictyostelium discoideum complexed with MgADP.BeFx and MgADP.AlF4-. Biochemistry. 1995 Jul 18;34(28):8960–8972. doi: 10.1021/bi00028a004. [DOI] [PubMed] [Google Scholar]
- Ford L. E., Huxley A. F., Simmons R. M. Tension responses to sudden length change in stimulated frog muscle fibres near slack length. J Physiol. 1977 Jul;269(2):441–515. doi: 10.1113/jphysiol.1977.sp011911. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gavish B., Werber M. M. Viscosity-dependent structural fluctuations in enzyme catalysis. Biochemistry. 1979 Apr 3;18(7):1269–1275. doi: 10.1021/bi00574a023. [DOI] [PubMed] [Google Scholar]
- Goldman Y. E. Measurement of sarcomere shortening in skinned fibers from frog muscle by white light diffraction. Biophys J. 1987 Jul;52(1):57–68. doi: 10.1016/S0006-3495(87)83188-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gordon A. M., LaMadrid M. A., Chen Y., Luo Z., Chase P. B. Calcium regulation of skeletal muscle thin filament motility in vitro. Biophys J. 1997 Mar;72(3):1295–1307. doi: 10.1016/S0006-3495(97)78776-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HUXLEY A. F. Muscle structure and theories of contraction. Prog Biophys Biophys Chem. 1957;7:255–318. [PubMed] [Google Scholar]
- Harford J. J., Squire J. M. Evidence for structurally different attached states of myosin cross-bridges on actin during contraction of fish muscle. Biophys J. 1992 Aug;63(2):387–396. doi: 10.1016/S0006-3495(92)81613-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Homsher E., Kim B., Bobkova A., Tobacman L. S. Calcium regulation of thin filament movement in an in vitro motility assay. Biophys J. 1996 Apr;70(4):1881–1892. doi: 10.1016/S0006-3495(96)79753-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Howard J. Molecular motors: structural adaptations to cellular functions. Nature. 1997 Oct 9;389(6651):561–567. doi: 10.1038/39247. [DOI] [PubMed] [Google Scholar]
- Howard J. The movement of kinesin along microtubules. Annu Rev Physiol. 1996;58:703–729. doi: 10.1146/annurev.ph.58.030196.003415. [DOI] [PubMed] [Google Scholar]
- Hunt A. J., Gittes F., Howard J. The force exerted by a single kinesin molecule against a viscous load. Biophys J. 1994 Aug;67(2):766–781. doi: 10.1016/S0006-3495(94)80537-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Huxley A. F., Simmons R. M. Proposed mechanism of force generation in striated muscle. Nature. 1971 Oct 22;233(5321):533–538. doi: 10.1038/233533a0. [DOI] [PubMed] [Google Scholar]
- Huxley H. E., Stewart A., Sosa H., Irving T. X-ray diffraction measurements of the extensibility of actin and myosin filaments in contracting muscle. Biophys J. 1994 Dec;67(6):2411–2421. doi: 10.1016/S0006-3495(94)80728-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Huxley H. E. The mechanism of muscular contraction. Science. 1969 Jun 20;164(3886):1356–1365. doi: 10.1126/science.164.3886.1356. [DOI] [PubMed] [Google Scholar]
- Iwazumi T., Pollack G. H. On-line measurement of sarcomere length from diffraction patterns in muscle. IEEE Trans Biomed Eng. 1979 Feb;26(2):86–93. doi: 10.1109/tbme.1979.326514. [DOI] [PubMed] [Google Scholar]
- Kushmerick M. J., Podolsky R. J. Ionic mobility in muscle cells. Science. 1969 Dec 5;166(3910):1297–1298. doi: 10.1126/science.166.3910.1297. [DOI] [PubMed] [Google Scholar]
- Levine R. J., Kensler R. W., Yang Z., Stull J. T., Sweeney H. L. Myosin light chain phosphorylation affects the structure of rabbit skeletal muscle thick filaments. Biophys J. 1996 Aug;71(2):898–907. doi: 10.1016/S0006-3495(96)79293-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lumry R. On the interpretation of data from isothermal processes. Methods Enzymol. 1995;259:628–720. doi: 10.1016/0076-6879(95)59065-x. [DOI] [PubMed] [Google Scholar]
- Martyn D. A., Chase P. B., Hannon J. D., Huntsman L. L., Kushmerick M. J., Gordon A. M. Unloaded shortening of skinned muscle fibers from rabbit activated with and without Ca2+. Biophys J. 1994 Nov;67(5):1984–1993. doi: 10.1016/S0006-3495(94)80681-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McKie J. E., Brandts J. F. High precision capillary viscometry. Methods Enzymol. 1972;26:257–288. doi: 10.1016/s0076-6879(72)26014-1. [DOI] [PubMed] [Google Scholar]
- Metzger J. M., Greaser M. L., Moss R. L. Variations in cross-bridge attachment rate and tension with phosphorylation of myosin in mammalian skinned skeletal muscle fibers. Implications for twitch potentiation in intact muscle. J Gen Physiol. 1989 May;93(5):855–883. doi: 10.1085/jgp.93.5.855. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Metzger J. M., Moss R. L. Calcium-sensitive cross-bridge transitions in mammalian fast and slow skeletal muscle fibers. Science. 1990 Mar 2;247(4946):1088–1090. doi: 10.1126/science.2309121. [DOI] [PubMed] [Google Scholar]
- Metzger J. M., Moss R. L. Shortening velocity in skinned single muscle fibers. Influence of filament lattice spacing. Biophys J. 1987 Jul;52(1):127–131. doi: 10.1016/S0006-3495(87)83197-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Metzger J. M., Moss R. L. Thin filament regulation of shortening velocity in rat skinned skeletal muscle: effects of osmotic compression. J Physiol. 1988 Apr;398:165–175. doi: 10.1113/jphysiol.1988.sp017036. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Molloy J. E., Burns J. E., Kendrick-Jones J., Tregear R. T., White D. C. Movement and force produced by a single myosin head. Nature. 1995 Nov 9;378(6553):209–212. doi: 10.1038/378209a0. [DOI] [PubMed] [Google Scholar]
- Moss R. L. Effects on shortening velocity of rabbit skeletal muscle due to variations in the level of thin-filament activation. J Physiol. 1986 Aug;377:487–505. doi: 10.1113/jphysiol.1986.sp016199. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Parsegian V. A., Rand R. P., Rau D. C. Macromolecules and water: probing with osmotic stress. Methods Enzymol. 1995;259:43–94. doi: 10.1016/0076-6879(95)59039-0. [DOI] [PubMed] [Google Scholar]
- Regnier M., Martyn D. A., Chase P. B. Calmidazolium alters Ca2+ regulation of tension redevelopment rate in skinned skeletal muscle. Biophys J. 1996 Nov;71(5):2786–2794. doi: 10.1016/S0006-3495(96)79471-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rüdel R., Zite-Ferenczy F. Do laser diffraction studies on striated muscle indicate stepwise sarcomere shortening? Nature. 1979 Apr 5;278(5704):573–575. doi: 10.1038/278573a0. [DOI] [PubMed] [Google Scholar]
- Sachs F., Latorre R. Cytoplasmic solvent structure of single barnacle muscle cells studied by electron spin resonance. Biophys J. 1974 Apr;14(4):316–326. doi: 10.1016/S0006-3495(74)85918-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schoenberg M. Characterization of the myosin adenosine triphosphate (M.ATP) crossbridge in rabbit and frog skeletal muscle fibers. Biophys J. 1988 Jul;54(1):135–148. doi: 10.1016/S0006-3495(88)82938-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Spudich J. A. How molecular motors work. Nature. 1994 Dec 8;372(6506):515–518. doi: 10.1038/372515a0. [DOI] [PubMed] [Google Scholar]
- Sweeney H. L., Bowman B. F., Stull J. T. Myosin light chain phosphorylation in vertebrate striated muscle: regulation and function. Am J Physiol. 1993 May;264(5 Pt 1):C1085–C1095. doi: 10.1152/ajpcell.1993.264.5.C1085. [DOI] [PubMed] [Google Scholar]
- Sweeney H. L., Corteselli S. A., Kushmerick M. J. Measurements on permeabilized skeletal muscle fibers during continuous activation. Am J Physiol. 1987 May;252(5 Pt 1):C575–C580. doi: 10.1152/ajpcell.1987.252.5.C575. [DOI] [PubMed] [Google Scholar]
- Sweeney H. L., Stull J. T. Alteration of cross-bridge kinetics by myosin light chain phosphorylation in rabbit skeletal muscle: implications for regulation of actin-myosin interaction. Proc Natl Acad Sci U S A. 1990 Jan;87(1):414–418. doi: 10.1073/pnas.87.1.414. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Thomas D. D., Ramachandran S., Roopnarine O., Hayden D. W., Ostap E. M. The mechanism of force generation in myosin: a disorder-to-order transition, coupled to internal structural changes. Biophys J. 1995 Apr;68(4 Suppl):135S–141S. [PMC free article] [PubMed] [Google Scholar]
- Uyeda T. Q., Kron S. J., Spudich J. A. Myosin step size. Estimation from slow sliding movement of actin over low densities of heavy meromyosin. J Mol Biol. 1990 Aug 5;214(3):699–710. doi: 10.1016/0022-2836(90)90287-V. [DOI] [PubMed] [Google Scholar]
- Uyeda T. Q., Warrick H. M., Kron S. J., Spudich J. A. Quantized velocities at low myosin densities in an in vitro motility assay. Nature. 1991 Jul 25;352(6333):307–311. doi: 10.1038/352307a0. [DOI] [PubMed] [Google Scholar]
- Yu L. C., Brenner B. Structures of actomyosin crossbridges in relaxed and rigor muscle fibers. Biophys J. 1989 Mar;55(3):441–453. doi: 10.1016/S0006-3495(89)82838-3. [DOI] [PMC free article] [PubMed] [Google Scholar]