Abstract
Myosins and kinesins are molecular motors that hydrolyse ATP to track along actin filaments and microtubules, respectively. Although the kinesin family includes motors that move towards either the plus or minus ends of microtubules1, all characterized myosin motors move towards the barbed (+) end of actin filaments2. Crystal structures of myosin II (refs 3,4,5,6) have shown that small movements within the myosin motor core are transmitted through the ‘converter domain’ to a ‘lever arm’ consisting of a light-chain-binding helix and associated light chains5,6. The lever arm further amplifies the motions of the converter domain into large directed movements3,5,6,7. Here we report that myosin VI, an unconventional myosin8,9,10,11,12, moves towards the pointed (-) end of actin. We visualized the myosin VI construct bound to actin using cryo-electron microscopy and image analysis, and found that an ADP-mediated conformational change in the domain distal to the motor, a structure likely to be the effective lever arm, is in the opposite direction to that observed for other myosins. Thus, it appears that myosin VI achieves reverse-direction movement by rotating its lever arm in the opposite direction to conventional myosin lever arm movement.
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
Bloom,G. S. & Endow,S. A. Motor proteins 1: kinesins. Protein Profile 2, 1105–1171 (1995).
Sellers,J. R. & Goodson,H. V. Motor proteins 2: myosin. Protein Profile 2, 1323–1423 (1995).
Rayment,I. et al. Three-dimensional structure of myosin subfragment-1: A molecular motor. Science 261, 50– 58 (1993).
Fisher,A. J. et al. X-ray structures of the myosin motor domain of Dictyostelium discoideum complexed with MgADP.BeFx and MgADP.AlF-4. Biochem. 34, 8960– 8972 (1995).
Dominguez,R., Freyzon,Y., Trybus,K. M. & Cohen,C. Crystal structure of a vertebrate smooth muscle myosin motor domain and its complex with the essential light chain: visualization of the pre-power stroke state. Cell 94, 559–571 ( 1998).
Houdusse,A., Kalabokis,V. N., Himmel,D., Szent-Gyorgyi,A. G. & Cohen,C. Atomic structure of scallop myosin subfragment S1 complexed with MgADP: a novel conformation of the myosin head. Cell 97, 459–470 (1999).
Whittaker,M. et al. A 35 Å movement of smooth muscle myosin on ADP release. Nature 378, 748– 751 (1995).
Mooseker,M. S. & Cheney,R. E. Unconventional myosins. Annu. Rev. Cell Dev. Biol. 11, 633– 675 (1995).
Kellerman,K. A. & Miller,K. G. An unconventional myosin heavy chain gene from Drosophila melanogaster. J. Cell Biol. 119, 823–834 (1992).
Hasson,T. & Mooseker,M. S. Porcine myosin VI: characterization of a new mammalian unconventional myosin. J. Cell Biol. 127, 425–440 (1994).
Avraham,K. B. et al. The mouse Snell's waltzer deafness gene encodes an unconventional myosin required for structural integrity of inner ear hair cells. Nature Genet. 11, 369–375 (1995).
Avraham,K. B. et al. Characterization of human unconventional myosin-VI, a gene responsible for deafness in Snell's waltzer mice. Hum. Mol. Genet. 6, 1225–1231 ( 1997).
Hasson,T. et al. Unconventional myosins in inner-ear sensory epithelia. J. Cell Biol. 137, 1287–1307 (1997).
Buss,F. et al. The localization of myosin VI at the Golgi complex and leading edge of fibroblasts and its phosphorylation and recruitment into membrane ruffles of A431 cells after growth factor stimulation. J. Cell Biol. 143, 1535–1545 ( 1998).
Mermall,V., McNally,J. G. & Miller, K. G. Transport of cytoplasmic particles catalysed by an unconventional myosin in living Drosophila embryos. Nature 369, 560–562 ( 1994).
Kron,S. J. & Spudich,J. A. Fluorescent actin filaments move on myosin fixed to a glass surface. Proc. Natl Acad. Sci. USA 83, 6272–6276 (1986).
Wolenski,J. S., Cheney,R. E., Mooseker,M. S. & Forscher,P. In vitro motility of immunoadsorbed brain myosin-V using a Limulus acrosomal process and optical tweezer-based assay. J. Cell Sci. 108, 1489–1496 ( 1995).
Jontes,J. D., Wilson-Kubalek,E. M. & Milligan, R. A. A 32 degree tail swing in brush border myosin I on ADP release. Nature 378, 751– 753 (1995).
Henningsen,U. & Schliwa,M. Reversal in the direction of movement of a molecular motor. Nature 389, 93– 96 (1997).
Sablin,E. P. et al. Direction determination in the minus-end-directed kinesin motor ncd. Nature 395, 813– 816 (1998).
Endow,S. A. & Waligora,K. W. Determinants of kinesin motor polarity. Science 281, 1200– 1202 (1998).
Hirose,K., Cross,R. A. & Amos,L. A. Nucleotide-dependent structural changes in dimeric NCD molecules complexed to microtubules. J. Mol. Biol. 278, 389–400 (1998).
Sosa,H. et al. A model for the microtubule-Ncd motor protein complex obtained by cryo-electron microscopy and image analysis. Cell 90, 217–224 (1997).
Sweeney,H. L. et al. Kinetic tuning of myosin via a flexible loop adjacent to the nucleotide binding pocket. J. Biol. Chem. 273, 6262–6270 (1998).
Hopp,T. P. et al. A short polypeptide marker sequence useful for recombinant protein identification and purification. Biotechnology 6, 1205–1210 (1988).
Kolodziej,P. A. & Young,R. A. Epitope tagging and protein surveillance. Methods Enzymol. 194, 508–519 (1991).
Espreafico,E. M. et al. Primary structure and cellular localization of chicken brain myosin-V (p190), an unconventional myosin with calmodulin light chains. J. Cell Biol. 119, 1541–1557 (1992).
Pollard,T. D. Assays for myosin. Methods Enzymol. 85, 123–130 (1982).
Elzinga,M. & Phelan,J. J. F-actin is intermolecularly crosslinked by N,N′-p-phenylenedimaleimide through lysine-191 and cysteine-374. Proc. Natl Acad. Sci. USA 81, 6599– 6602 (1984).
Jontes,J. D. & Milligan,R. A. Brush border myosin-I structure and ADP-dependent conformational changes revealed by cryoelectron microscopy and image analysis. J. Cell Biol. 139, 683 –693 (1997).
Acknowledgements
This work was supported by grants from the NIH. We thank M. S. Mooseker for the chicken myosin V cDNA, and G. Daniels of Leica Microsystems for technical support.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Wells, A., Lin, A., Chen, LQ. et al. Myosin VI is an actin-based motor that moves backwards. Nature 401, 505–508 (1999). https://doi.org/10.1038/46835
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/46835
This article is cited by
A joint proteomic and genomic investigation provides insights into the mechanism of calcification in coccolithophores
Nature Communications (2023)
Nuclear myosin VI maintains replication fork stability
Nature Communications (2023)
In focus in HCB
Histochemistry and Cell Biology (2021)
Diverse functions of myosin VI in spermiogenesis
Histochemistry and Cell Biology (2021)
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.