Forces measured with micro-fabricated cantilevers during actomyosin interactions produced by filaments containing different myosin isoforms and loop 1 structures

Kalganov, Albert; Shalabi, Nabil; Zitouni, Nedjma B.; Kachmar, Linda; Lauzon, Anne‐Marie; Rassier, Dilson E.

doi:10.1016/j.bbagen.2012.11.022

Cited by 12 publications

(15 citation statements)

References 68 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We next tested the force developed by the isolated myosin filaments using micro-fabricated cantilevers of known stiffness (Kalganov et al, 2010; Kalganov et al, 2013). In this assay, a myosin filament attached to a cantilever is brought into contact with an actin filament that is attached to another cantilever coated with α-actinin.…”

Section: Resultsmentioning

confidence: 99%

“…Once the filaments interacted, they initiated force production and consequently displacement of the cantilevers, which was tracked with Image software (NIH, USA). The forces were calculated from the displacements of the cantilevers as explained previously (Kalganov et al , 2010;Kalganov et al , 2013). Briefly, the force (F) was calculated as F = K * Ad (cantilever displacement).…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Arginylation of Myosin Heavy Chain Regulates Skeletal Muscle Strength

et al. 2014

Self Cite

View full text Add to dashboard Cite

Protein arginylation is a post-translational modification with an emerging global role in the regulation of actin cytoskeleton. To test the role of arginylation in the skeletal muscle, we generated a mouse model with Ate1 knockout driven by skeletal muscle-specific creatine kinase (Ckmm) promoter. Such Ckmm-Ate1 mice were viable and outwardly normal, however their skeletal muscle strength was significantly reduced compared to the control. Mass spectrometry of the isolated skeletal myofibrils showed a limited set of proteins arginylated on specific sites, including myosin heavy chain. Atomic force microscopy measurements of the contractile strength in individual myofibrils and isolated myosin filaments from these mice showed a significant reduction of contractile forces, which, in the case of the myosin filaments could be fully rescued by re-arginylation with purified Ate1. Our results demonstrate that arginylation regulates force production in the muscle and exerts a direct effect on muscle strength through arginylation of myosin.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Arginylation of Myosin Heavy Chain Regulates Skeletal Muscle Strength

et al. 2014

Self Cite

View full text Add to dashboard Cite

show abstract

“…The limits intrinsic in our design, consisting in reduced force and step size generated by randomly oriented motors, could be overcome by motor systems such as the native isolated thick filament or the synthetic cofilament made of rods and myosin molecules [ 39 ]. However, the performance of the systems based on single actin–single myosin filament [ 39 , 40 , 41 ] appears systematically limited to transient displacements of the actin filament abruptly interrupted after variable time periods, failing to produce steady force and power by a constant number of interacting motors. The reason for the success of our design is the possibility to ensure that the array of interacting motors and the actin filament lie on parallel planes, in this way preserving the in situ motor condition of being “in-parallel force generators”.…”

Section: Discussionmentioning

confidence: 99%

A Myosin II-Based Nanomachine Devised for the Study of Ca2+-Dependent Mechanisms of Muscle Regulation

Pertici

Bianchi

Bongini

et al. 2020

IJMS

View full text Add to dashboard Cite

The emergent properties of the array arrangement of the molecular motor myosin II in the sarcomere of the striated muscle, the generation of steady force and shortening, can be studied in vitro with a synthetic nanomachine made of an ensemble of eight heavy-meromyosin (HMM) fragments of myosin from rabbit psoas muscle, carried on a piezoelectric nanopositioner and brought to interact with a properly oriented actin filament attached via gelsolin (a Ca2+-regulated actin binding protein) to a bead trapped by dual laser optical tweezers. However, the application of the original version of the nanomachine to investigate the Ca2+-dependent regulation mechanisms of the other sarcomeric (regulatory or cytoskeleton) proteins, adding them one at a time, was prevented by the impossibility to preserve [Ca2+] as a free parameter. Here, the nanomachine is implemented by assembling the bead-attached actin filament with the Ca2+-insensitive gelsolin fragment TL40. The performance of the nanomachine is determined both in the absence and in the presence of Ca2+ (0.1 mM, the concentration required for actin attachment to the bead with gelsolin). The nanomachine exhibits a maximum power output of 5.4 aW, independently of [Ca2+], opening the possibility for future studies of the Ca2+-dependent function/dysfunction of regulatory and cytoskeletal proteins.

show abstract

“…Actin was purified from acetone powder of rabbit skeletal muscle (Sigma-Aldrich) according to a protocol (51). Myosin was purified from rabbit psoas muscle as described (52). HMM was prepared by proteolysis of the myosin with α-chymotrypsin (Sigma-Aldrich) according to protocols described here (53).…”

Section: Methodsmentioning

confidence: 99%

High-speed AFM reveals subsecond dynamics of cardiac thin filaments upon Ca ²⁺ activation and heavy meromyosin binding

Matusovsky

Månsson

Persson

et al. 2019

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

High-speed atomic force microscopy (HS-AFM) can be used to study dynamic processes with real-time imaging of molecules within 1- to 5-nm spatial resolution. In the current study, we evaluated the 3-state model of activation of cardiac thin filaments (cTFs) isolated as a complex and deposited on a mica-supported lipid bilayer. We studied this complex for dynamic conformational changes 1) at low and high [Ca2+] (pCa 9.0 and 4.5), and 2) upon myosin binding to the cTF in the nucleotide-free state or in the presence of ATP. HS-AFM was used to directly visualize the tropomyosin–troponin complex and Ca2+-induced tropomyosin movements accompanied by structural transitions of actin monomers within cTFs. Our data show that cTFs at relaxing or activating conditions are not ultimately in a blocked or activated state, respectively, but rather the combination of states with a prevalence that is dependent on the [Ca2+] and the presence of weakly or strongly bound myosin. The weakly and strongly bound myosin induce similar changes in the structure of cTFs as confirmed by the local dynamical displacement of individual tropomyosin strands in the center of a regulatory unit of cTF at the relaxed and activation conditions. The displacement of tropomyosin at the relaxed conditions had never been visualized directly and explains the ability of myosin binding to TF at the relaxed conditions. Based on the ratios of nonactivated and activated segments within cTFs, we proposed a mechanism of tropomyosin switching from different states that includes both weakly and strongly bound myosin.

show abstract

Forces measured with micro-fabricated cantilevers during actomyosin interactions produced by filaments containing different myosin isoforms and loop 1 structures

Cited by 12 publications

References 68 publications

Arginylation of Myosin Heavy Chain Regulates Skeletal Muscle Strength

Arginylation of Myosin Heavy Chain Regulates Skeletal Muscle Strength

A Myosin II-Based Nanomachine Devised for the Study of Ca2+-Dependent Mechanisms of Muscle Regulation

High-speed AFM reveals subsecond dynamics of cardiac thin filaments upon Ca ²⁺ activation and heavy meromyosin binding

Contact Info

Product

Resources

About

Forces measured with micro-fabricated cantilevers during actomyosin interactions produced by filaments containing different myosin isoforms and loop 1 structures

Cited by 12 publications

References 68 publications

Arginylation of Myosin Heavy Chain Regulates Skeletal Muscle Strength

Arginylation of Myosin Heavy Chain Regulates Skeletal Muscle Strength

A Myosin II-Based Nanomachine Devised for the Study of Ca2+-Dependent Mechanisms of Muscle Regulation

High-speed AFM reveals subsecond dynamics of cardiac thin filaments upon Ca 2+ activation and heavy meromyosin binding

Contact Info

Product

Resources

About

High-speed AFM reveals subsecond dynamics of cardiac thin filaments upon Ca ²⁺ activation and heavy meromyosin binding