Myosin II tension sensors visualize force generation within the actin cytoskeleton in living cells

Ryan G Hart; Divya Kota; Fangjia Li; Mengdi Zhang; Diego Ramallo; Andrew J Price; Karla L Otterpohl; Steve J Smith; Alexander R Dunn; Mark O Huising; Jing Liu; Indra Chandrasekar

doi:10.1242/jcs.262281

Myosin II tension sensors visualize force generation within the actin cytoskeleton in living cells

J Cell Sci. 2024 Oct 4:jcs.262281. doi: 10.1242/jcs.262281. Online ahead of print.

Authors

Ryan G Hart^{1

2}, Divya Kota³, Fangjia Li⁴, Mengdi Zhang⁴, Diego Ramallo⁵, Andrew J Price⁵, Karla L Otterpohl¹, Steve J Smith³, Alexander R Dunn⁶, Mark O Huising^{2

7}, Jing Liu^{4

8}, Indra Chandrasekar^{1

9}

Affiliations

¹ Enabling Technologies Group, Sanford Research, Sioux Falls, SD, 57104, USA.
² Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA 95616, USA.
³ Department of Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
⁴ Department of Physics, Indiana University-Purdue University Indianapolis, Indianapolis, IN, 46202, USA.
⁵ Biophysics Program, Stanford University, Stanford, CA, 94305, USA.
⁶ Department of Chemical Biology, Stanford University, Stanford, CA, 94305, USA.
⁷ Department of Physiology and Membrane Biology, School of Medicine, University of California Davis, Davis, CA 95616, USA.
⁸ Department of Physics and Astronomy, Purdue University, West Lafayette, IN 46907, USA.
⁹ Department of Pediatrics, University of South Dakota, Sioux Falls, SD, 57105, USA.

PMID: 39369303
DOI: 10.1242/jcs.262281

Abstract

Nonmuscle myosin II generates cytoskeletal forces that drive cell division, embryogenesis, muscle contraction, and many other cellular functions. However, at present there is no method that can directly measure the forces generated by myosins in living cells. Here we describe a Förster resonance energy transfer (FRET)-based tension sensor that can detect myosin associated force along the filamentous actin network. Fluorescence lifetime imaging microscopy (FLIM)-FRET measurements indicate that the forces generated by NMIIB exhibit significant spatial and temporal heterogeneity as a function of donor lifetime and fluorophore energy exchange. These measurements provide a proxy for inferred forces that vary widely along the actin cytoskeleton. This initial report highlights the potential utility of myosin-based tension sensors in elucidating the roles of cytoskeletal contractility in a wide variety of contexts.

Keywords: Actomyosin; Force in living cells; Tension Sensor.

Abstract

Grants and funding