Research

Mechanical interaction with the environment

Mechanical communication between cells

The unique nonlinear mechanics of the fibrous extracellular matrix (ECM) facilitates propagation of forces, supporting a mechanism of long-range cell-cell mechanical communication that would be impossible for linear elastic substrates. When seeded in fibrous gels, pairs of cells or cell aggregates can induce bands of deformed gel extending between them, indicating their mechanical coupling. We use computational finite element simulations and biological experiments to reveal how mechanical forces, exerted by contractile cells, are transmitted in fibrous nonlinear environments, and how these forces can reach out neighboring cells and regulate their biological activity.

Related papers:

• David Gomez, Eial Teomy, Ayelet Lesman, Yair Shokef. Target finding in fibrous biological environments. New J. Phys. New J. Phys. 22 103008 Oct 2020. https://doi.org/10.1088/1367-2630/abb64b
• Assaf Nahum, Yoni Koren, Sari Natan, Shahar Goren, Ayelet Lesman, Assaf Zaritsky. Quantifying the dynamics of long-range cell-cell mechanical communication. July 2020, bioRxiv preprint. doi: https://doi.org/10.1101/2020.07.30.223149
• Sari Natan, Yoni Koren, Ortal Shelah, Shahar Goren, Ayelet Lesman. Long-range mechanical coupling of cells in 3D fibrin gels. Molecular Biology of the Cell, Volume 31, No. 14, July 2020. https://doi.org/10.1091/mbc.E20-01-0079. * This article appears on the cover
• Shahar Goren, Yoni Koren, Xinpeng Xu, Ayelet Lesman. Elastic Anisotropy Governs the Range of Cell-Induced Displacements. Biophysical Journal. March 2020 .Volume 118, Issue 5, 10 March 2020, Pages 1152-1164. https://doi.org/10.1007/s10439-019-02426-7
• David Gomez, Sari Natan, Yair Shokef, Ayelet Lesman. Mechanical Interaction between Cells Facilitates Molecular Transport. Advanced Biosystems, Volume 3, Issue 12, November 2019. https://doi.org/10.1002/adbi.201900192
• Amots Mann, Ran S Sopher, Shahar Goren, Ortal Shelah, Oren Tchaicheeyan, Ayelet Lesman. Force chains in cell-cell mechanical communication. Journal of the Royal Society Interface. 16 (159), Oct 2019.
• Ran S Sopher, Hanan Tokash, Sari Natan, Mirit Sharabi, Ortal Shelah, Oren Tchaicheeyan, Ayelet Lesman. Nonlinear elasticity of the ECM fibers facilitates efficient inter-cellular communication. Biophysical J. 2;115(7):1357-1370, 2018. *This article appears on the cover

Force transmission in anisotropic fibrous environments

The mechanical and structural properties of fibrous materials dynamically evolve and develop as they are strained. Together with Dr. Raya Sorkin (Chemistry, TAU), we use laser tweezers to study how forces propagate in fibrous gels that are put under tension and become elastically anisotropic. This line of research provides insight into the mechanisms how mechanical cues are transmitted between biological cells, and provide inspiration for the design of new biomaterials.

Forces exerted by growing roots

Plant roots are considered one of the most efficient soil explorers. As opposed to the penetration strategy of other organisms, that is based on pushing through soil, roots penetrate by growing, adding new cells at the tip and elongating over a well-defined growth zone. In collaboration with Dr. Yasmin Meroz (Plant Sciences, TAU), we study the forces applied by plant roots in agar gel by traction force microscopy, and use finite element modeling to reveal the advantages of the growth mechanism.