Abstract
α-Helical coiled coils in muscle exemplify simplicity and economy of protein design: small variations in sequence lead to remarkable diversity in cellular functions1,2. Myosin II is the key protein in muscle contraction, and the molecule's two-chain α-helical coiled-coil rod region—towards the carboxy terminus of the heavy chain—has unusual structural and dynamic features. The amino-terminal subfragment-2 (S2) domains of the rods can swing out from the thick filament backbone at a hinge in the coiled coil, allowing the two myosin ‘heads’ and their motor domains to interact with actin and generate tension3. Most of the S2 rod appears to be a flexible coiled coil, but studies suggest that the structure at the N-terminal region is unstable4,5,6, and unwinding or bending of the α-helices near the head–rod junction seems necessary for many of myosin's functional properties7,8. Here we show the physical basis of a particularly weak coiled-coil segment by determining the 2.5-Å-resolution crystal structure of a leucine-zipper-stabilized fragment of the scallop striated-muscle myosin rod adjacent to the head–rod junction. The N-terminal 14 residues are poorly ordered; the rest of the S2 segment forms a flexible coiled coil with poorly packed core residues. The unusual absence of interhelical salt bridges here exposes apolar core atoms to solvent.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Cohen, C. & Parry, D. A. D. α-Helical coiled coils and bundles: How to design an α-helical protein. Proteins 7, 1–15 (1990)
Lupas, A. Coiled coils: New structures and new functions. Trends Biochem. Sci. 21, 375–382 (1996)
Huxley, H. E. The mechanism of muscular contraction. Science 164, 1356–1365 (1969)
Trybus, K. M. Regulation of expressed truncated smooth muscle myosins. Role of the essential light chain and tail length. J. Biol. Chem. 269, 20819–20822 (1994)
Knight, P. J. Dynamic behavior of the head–tail junction of myosin. J. Mol. Biol. 255, 269–274 (1996)
Malnasi-Csizmadia, A., Shimony, E., Hegyi, G., Szent-Györgyi, A. G. & Nyitray, L. Dimerization of the head–rod junction of scallop myosin. Biochem. Biophys. Res. Commun. 252, 595–601 (1998)
Lauzon, A. M., Fagnant, P. M., Warshaw, D. M. & Trybus, K. M. Coiled-coil unwinding at the smooth muscle myosin head–rod junction is required for optimal mechanical performance. Biophys. J. 80, 1900–1904 (2001)
Liu, J., Wendt, T., Taylor, D. & Taylor, K. Refined model of the 10 S conformation of smooth muscle myosin by cryo-electron microscopy 3D image reconstruction. J. Mol. Biol. 329, 963–972 (2003)
Crick, F. H. C. The packing of α helices: simple coiled-coils. Acta Crystallogr. 6, 689–697 (1953)
O'Shea, E. K., Klemm, J. D., Kim, P. S. & Alber, T. X-ray structure of the GCN4 leucine zipper, a two-stranded, parallel coiled coil. Science 254, 539–544 (1991)
Li, Y. et al. The crystal structure of the C-terminal fragment of striated-muscle α-tropomyosin reveals a key troponin T recognition site. Proc. Natl Acad. Sci. USA 99, 7378–7383 (2002)
Gruen, M. & Gautel, M. Mutations in β-myosin S2 that cause familial hypertrophic cardiomyopathy (FHC) abolish the interaction with the regulatory domain of myosin-binding protein-C. J. Mol. Biol. 286, 933–949 (1999)
McLachlan, A. D. & Stewart, M. Tropomyosin coiled-coil interactions: Evidence for an unstaggered structure. J. Mol. Biol. 98, 293–304 (1975)
Kammerer, R. A. et al. An autonomous folding unit mediates the assembly of two-stranded coiled coils. Proc. Natl Acad. Sci. USA 95, 13419–13424 (1998)
Burkhard, P., Kammerer, R. A., Steinmetz, M. O., Bourenkov, G. P. & Aebi, U. The coiled-coil trigger site of the rod domain of cortexillin I unveils a distinct network of interhelical and intrahelical salt bridges. Structure 8, 223–230 (2000)
Meier, M., Lustig, A., Aebi, U. & Burkhard, P. Removing an interhelical salt bridge abolishes coiled-coil formation in a de novo designed peptide. J. Struct. Biol. 137, 65–72 (2002)
Burkhard, P., Ivaninskii, S. & Lustig, A. Improving coiled-coil stability by optimizing ionic interactions. J. Mol. Biol. 318, 901–910 (2002)
Arndt, K., Pelletier, J., Muller, K., Pluckthun, A. & Alber, T. Comparison of in vivo selection and rational design of heterodimeric coiled coils. Structure 10, 1235–1248 (2002)
Conway, J. F. & Parry, D. A. D. Structural features in the heptad substructure and longer range repeats of two-stranded α-fibrous proteins. Int. J. Biol. Macromol. 12, 328–334 (1990)
McLachlan, A. D. & Karn, J. Periodic features in the amino acid sequence of nematode myosin rod. J. Mol. Biol. 164, 605–626 (1983)
Woolfson, D. N. & Alber, T. Predicting oligomerization states of coiled coils. Protein Sci. 4, 1596–1607 (1995)
Adelstein, R. S. & Eisenberg, E. Regulation and kinetics of the actin–myosin–ATP interaction. Annu. Rev. Biochem. 49, 921–956 (1980)
Burgess S. et al. Structure of smooth muscle myosin in the switched-off state. Biophys. J. (annual meeting abstracts), 356a (2002)
Stafford, W. F. et al. Calcium-dependent structural changes in scallop heavy meromyosin. J. Mol. Biol. 307, 137–147 (2001)
Nyitrai, M., Szent-Györgyi, A. G. & Geeves, M. A. A kinetic model of the co-operative binding of calcium and ADP to scallop (Argopecten irradians) heavy meromyosin. Biochem. J. 365, 19–30 (2002)
Chakrabarty, T., Xiao, M., Cooke, R. & Selvin, P. R. Holding two heads together: Stability of the myosin II rod measured by resonance energy transfer between the heads. Proc. Natl Acad. Sci. USA 99, 6011–6016 (2002)
Tomishige, M. & Vale, R. D. Controlling kinesin by reversible disulfide cross-linking. Identifying the motility-producing conformational change. J. Cell Biol. 151, 1081–1092 (2000)
Buss, F., Luzio, J. P. & Kendrick-Jones, J. Myosin VI, a new force in clathrin mediated endocytosis. FEBS Lett. 508, 295–299 (2001)
Burkhard, P., Stetefeld, J. & Strelkov, S. V. Coiled coils: A highly versatile protein folding motif. Trends Cell Biol. 11, 82–88 (2001)
Brown, J. H. et al. Deciphering the design of the tropomyosin molecule. Proc. Natl Acad. Sci. USA 98, 8496–8501 (2001)
Collaborative Computational Project, Number 4. Acta Crystallogr. D 50, 760–763 (1994)
Acknowledgements
We thank D. A. D. Parry, A. G. Szent-Györgyi and H. E. Huxley for a critical reading of the manuscript, and the staff of the Cornell High Energy Synchrotron Source for assistance with data collection. This work has been supported by grants to C.C. from the National Institutes of Health and the Muscular Dystrophy Association, and to L.N. from the Hungarian Scientific Research Fund (OTKA).
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Competing interests
The authors declare that they have no competing financial interests.
Supplementary information
41586_2003_BFnature01801_MOESM1_ESM.doc
Supplementary Information: The supplementary material provides the details of the expression, purification, crystallization, and structure determination (including a Table of X-ray data collection and refinement statistics) of the (leucine-zipper stabilized) 51-residue N-terminal fragment of scallop myosin subfragment-2. (DOC 30 kb)
Rights and permissions
About this article
Cite this article
Li, Y., Brown, J., Reshetnikova, L. et al. Visualization of an unstable coiled coil from the scallop myosin rod. Nature 424, 341–345 (2003). https://doi.org/10.1038/nature01801
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/nature01801
This article is cited by
-
Structure, interactions and function of the N-terminus of cardiac myosin binding protein C (MyBP-C): who does what, with what, and to whom?
Journal of Muscle Research and Cell Motility (2012)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.