» Articles » PMID: 22171985

How Myosin Motors Power Cellular Functions: an Exciting Journey from Structure to Function: Based on a Lecture Delivered at the 34th FEBS Congress in Prague, Czech Republic, July 2009

Overview
Journal FEBS J
Specialty Biochemistry
Date 2011 Dec 17
PMID 22171985
Citations 5
Authors
Affiliations
Soon will be listed here.
Abstract

Molecular motors such as myosins are allosteric enzymes that power essential motility functions in the cell. Structural biology is an important tool for deciphering how these motors work. Myosins produce force upon the actin-driven conformational changes controlling the sequential release of the hydrolysis products of ATP (Pi followed by ADP). These conformational changes are amplified by a 'lever arm', which includes the region of the motor known as the converter and the adjacent elongated light chain binding region. Analysis of four structural states of the motor provides a detailed understanding of the rearrangements and pathways of communication in the motor that are necessary for detachment from the actin track and repriming of the motor. However, the important part of the cycle in which force is produced remains enigmatic and awaits new high-resolution structures. The value of a structural approach is particularly evident from clues provided by the structural states of the reverse myosin VI motor. Crystallographic structures have revealed that rearrangements within the converter subdomain occur, which explains why this myosin can produce a large stroke in the opposite direction to all other myosins, despite a very short lever arm. By providing a detailed understanding of the motor rearrangements, structural biology will continue to reveal essential information and help solve current enigma, such as how actin promotes force production, how motors are tuned for specific cellular roles or how motor/cargo interactions regulate the function of myosin in the cell.

Citing Articles

Thermodynamics and Kinetics of a Binary Mechanical System: Mechanisms of Muscle Contraction.

Baker J Langmuir. 2022; 38(51):15905-15916.

PMID: 36520019 PMC: 9798825. DOI: 10.1021/acs.langmuir.2c01622.


Investigations of human myosin VI targeting using optogenetically controlled cargo loading.

French A, Sosnick T, Rock R Proc Natl Acad Sci U S A. 2017; 114(9):E1607-E1616.

PMID: 28193860 PMC: 5338553. DOI: 10.1073/pnas.1614716114.


Two Essential Light Chains Regulate the MyoA Lever Arm To Promote Toxoplasma Gliding Motility.

Williams M, Alonso H, Enciso M, Egarter S, Sheiner L, Meissner M mBio. 2015; 6(5):e00845-15.

PMID: 26374117 PMC: 4600101. DOI: 10.1128/mBio.00845-15.


Effects of ATP and actin-filament binding on the dynamics of the myosin II S1 domain.

Baker J, Voth G Biophys J. 2013; 105(7):1624-34.

PMID: 24094403 PMC: 3791303. DOI: 10.1016/j.bpj.2013.08.023.


Force generation by kinesin and myosin cytoskeletal motor proteins.

Kull F, Endow S J Cell Sci. 2013; 126(Pt 1):9-19.

PMID: 23487037 PMC: 3603507. DOI: 10.1242/jcs.103911.

References
1.
Lymn R, Taylor E . Mechanism of adenosine triphosphate hydrolysis by actomyosin. Biochemistry. 1971; 10(25):4617-24. DOI: 10.1021/bi00801a004. View

2.
Spink B, Sivaramakrishnan S, Lipfert J, Doniach S, Spudich J . Long single alpha-helical tail domains bridge the gap between structure and function of myosin VI. Nat Struct Mol Biol. 2008; 15(6):591-7. PMC: 2441774. DOI: 10.1038/nsmb.1429. View

3.
McConnell R, Tyska M . Leveraging the membrane - cytoskeleton interface with myosin-1. Trends Cell Biol. 2010; 20(7):418-26. PMC: 2897960. DOI: 10.1016/j.tcb.2010.04.004. View

4.
Hartman M, Finan D, Sivaramakrishnan S, Spudich J . Principles of unconventional myosin function and targeting. Annu Rev Cell Dev Biol. 2011; 27:133-55. PMC: 4787598. DOI: 10.1146/annurev-cellbio-100809-151502. View

5.
Ali M, Homma K, Iwane A, Adachi K, Itoh H, Kinosita Jr K . Unconstrained steps of myosin VI appear longest among known molecular motors. Biophys J. 2004; 86(6):3804-10. PMC: 1304281. DOI: 10.1529/biophysj.103.037416. View