Bipolar filaments of human nonmuscle myosin 2-A and 2-B have distinct motile and mechanical properties
- National Heart, Lung and Blood Institute, National Institutes of Health, United States
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, United States
- National Institutes of Allergy and Infectious Diseases, National Institutes of Health, United States
Abstract
Nonmuscle myosin 2 (NM-2) powers cell motility and tissue morphogenesis by assembling into bipolar filaments that interact with actin. Although the enzymatic properties of purified NM-2 motor fragments have been determined, the emergent properties of filament ensembles are unknown. Using single myosin filament in vitro motility assays, we report fundamental differences in filaments formed of different NM-2 motors. Filaments consisting of NM2-B moved processively along actin, while under identical conditions, NM2-A filaments did not. By more closely mimicking the physiological milieu, either by increasing solution viscosity or by co-polymerization with NM2-B, NM2-A containing filaments moved processively. Our data demonstrate that both the kinetic and mechanical properties of these two myosins, in addition to the stochiometry of NM-2 subunits, can tune filament mechanical output. We propose altering NM-2 filament composition is a general cellular strategy for tailoring force production of filaments to specific functions such as maintaining tension or remodeling actin.
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Funding
National Heart, Lung, and Blood Institute (HL001786)
- Jonathan E Bird
- Attila Nagy
National Institute on Deafness and Other Communication Disorders (DC000039)
- Thomas B Friedman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
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This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Bipolar filaments of human nonmuscle myosin 2-A and 2-B have distinct motile and mechanical properties
eLife 7:e32871.
https://doi.org/10.7554/eLife.32871
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