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Internet Electronic Journal of Molecular Design - IEJMD, ISSN 1538-6414, CODEN IEJMAT
| ABSTRACT - Internet Electron. J. Mol. Des. October 2003, Volume 2, Number 10, 642-652 |
Traction, Trypsin, and Tensegrity
Iva Marija Tolic-Nørrelykke and Ning Wang
Internet Electron. J. Mol. Des. 2003, 2, 642-652
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Abstract:
Cells exert traction on their substrates. These mechanical stresses
are crucial in cell contraction, locomotion, growth, and
differentiation. The cells are plated on a flexible gel substrate
with embedded fluorescent microbeads. The traction of the cells
induces a deformation of the gel and hence displacement of the
microbeads. These displacements are used to compute the
traction by Fourier Transform Traction Cytometry (FTTC). The
FTTC method was tested using computer simulations. The
method was applied to cultured human airway smooth muscle
cells before and after their partial detachment from the substrate,
induced by trypsin. Before detachment, the traction was highest
at the cell ends, whereas there was no traction after partial
detachment. Adherent cells are tensed and attached to the
substrate mainly at their ends. After one end of the cell detaches,
the cell rebounds like a spring to its intact attachment site. The
cells typically retract towards the site of highest traction,
possibly because this is the site of strong attachments. Retraction
of the cell after partial detachment is consistent with the
tensegrity model of cell mechanics, in which tension in the
cytoskeleton is crucial for the mechanical stability of cells.
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