Myosins

Abstract

Myosins are molecular motors that move or interact with actin filaments to perform a variety of functions in cells. The multiple myosin genes in humans contain a conserved motor domain that harbors the machinery needed to interact with actin and hydrolyze ATP. Other functional domains exist to determine the localization and anchoring of the molecule.

Keywords: myosin; molecular motor; ATPase; motility; deafness; actomyosin; cytoskeleton

Figure 1.

Phylogenetic tree of the human myosin superfamily. Solid lines indicate myosins for which chromosomal deoxyribonucleic acid (cDNA) sequences exist, and dashed lines indicate putative myosins predicted from genomic sequence. Recently discovered or newly predicted myosin genes are italicized, and potential gene names suggested for myosins predicted from genomic sequence are indicated in parentheses. The tree was modified from the one provided by R. Cheney (Berg et al., ).

Figure 2.

Crystal structure of the head of scallop striated muscle myosin. The three‐dimensional structure of the scallop striated muscle head fragment protein 1DFK is shown in ribbon format. The myosin heavy chain is depicted in blue, the essential light chain in red and the regulatory light chain in green.

Figure 3.

Bar diagrams of the heavy chains of the human myosin superfamily. A representative myosin from each class found in humans is shown. The various functional domains are color‐coded and are drawn approximately to scale.

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References

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Further Reading

El‐Amraoui A, Schonn JS, Kussel‐Andermann P, et al. (2002) MyRIP, a novel Rab effector, enables myosin VIIa recruitment to retinal melanosomes. The EMBO Journal 3: 463–470.

Homma K, Yoshimura M, Saito J, Ikebe R and Ikebe M (2001) The core of the motor domain determines the direction of myosin movement. Nature 412: 831–834.

Oliver TN, Berg JS and Cheney RE (1999) Tails of unconventional myosins. Cellular and Molecular Life Sciences 56: 243–257.

Spudich JA (2001) The myosin swinging cross‐bridge model. Nature Reviews Molecular Cell Biology 2: 387–392.

Uren D, Hwang HK, Hara Y, et al. (2000) Gene dosage affects the cardiac and brain phenotype in nonmuscle myosin II‐B‐depleted mice. Journal of Clinical Investigation 105: 663–671.

Wu XS, Rao K, Zhang H, et al. (2002) Identification of an organelle receptor for myosin‐Va. Nature Cell Biology 4: 271–278.

Web Links

myosin, heavy polypeptide 7, cardiac muscle, β (MYH7); LocusID: 4625. LocusLink: http://www.ncbi.nlm.nih.gov/LocusLink/LocRpt.cgi?l=4625

myosin IIIA (MYO3A); LocusID: 53904. LocusLink: http://www.ncbi.nlm.nih.gov/LocusLink/LocRpt.cgi?l=53904

myosin VA (MYO5A); LocusID: 4644. LocusLink: http://www.ncbi.nlm.nih.gov/LocusLink/LocRpt.cgi?l=4644

myosin VIIA (MYO7A); LocusID: 4647. LocusLink: http://www.ncbi.nlm.nih.gov/LocusLink/LocRpt.cgi?l=4647

myosin XVA (MYO15A); LocusID: 51168. LocusLink: http://www.ncbi.nlm.nih.gov/LocusLink/LocRpt.cgi?l=51168

myosin, heavy polypeptide 7, cardiac muscle, β (MYH7); MIM number: 160760. OMIM: http://www.ncbi.nlm.nih.gov/htbin‐post/Omim/dispmim?160760

myosin IIIA (MYO3A); MIM number: 606808. OMIM: http://www.ncbi.nlm.nih.gov/htbin‐post/Omim/dispmim?606808

myosin VA (MYO5A); MIM number: 160777. OMIM: http://www.ncbi.nlm.nih.gov/htbin‐post/Omim/dispmim?160777

myosin VIIA (MYO7A); MIM number: 276903. OMIM: http://www.ncbi.nlm.nih.gov/htbin‐post/Omim/dispmim?276903

myosin XVA (MYO15A); MIM number: 602666. OMIM: http://www.ncbi.nlm.nih.gov/htbin‐post/Omim/dispmim?602666

Human Genome Organization (HUGO) http://www.gene.ucl.ac.uk/nomenclature/

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How to Cite close
Sellers, James R(Sep 2006) Myosins. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0006149]