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| TR |
TITLE |
AUTHORS |
KEYWORDS |
MATERIALS & METHODS
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MICROSCOPIC
TECHNIQUES |
SPECIES |
MORPHOLOGY |
CELL
LINE |
| 595 |
Cellular
adaptation to mechanical stress: role of integrins, Rho, cytoskeletal tension and mechanosensitive
ion channels |
Benjamin
D. Matthews, Darryl R. Overby, Robert Mannix and Donald E. Ingber |
Integrin,
Focal adhesion, Mechanotransduction,
Prestress, Tension, Magnetometry |
In preparation for experiments,
cells were cultured in DMEM with 0.5% FCS for 24 hours, trypsinized (Trypsin-EDTA, Gibco), and
then plated (1.5104 cells/dish) onto glass-bottomed 35 mm dishes (MatTek Corp)…
|
optical
microscopy |
bovine |
|
capillary
endothelial |
| Abstract |
| |
To understand how cells sense and adapt to mechanical
stress, we applied tensional forces to magnetic microbeads bound to cell-surface integrin receptors
and measured changes in bead displacement with sub-micrometer resolution using optical microscopy.
Cells exhibited four types of mechanical responses: (1) an immediate viscoelastic response;
(2) early adaptive behavior characterized by pulse-to-pulse attenuation in response to oscillatory
forces; (3) later adaptive cell stiffening with sustained (>15 second) static stresses; and
(4) a large-scale repositioning response with prolonged (>1 minute) stress. Importantly,
these adaptation responses differed biochemically. The immediate and early responses were affected
by chemically dissipating cytoskeletal prestress (isometric tension), whereas the later adaptive
response was not. The repositioning response was prevented by inhibiting tension through interference
with Rho signaling, similar to the case of the immediate and early responses, but it was also
prevented by blocking mechanosensitive ion channels or by inhibiting Src tyrosine kinases. All
adaptive responses were suppressed by cooling cells to 4°C to slow biochemical remodeling.
Thus, cells use multiple mechanisms to sense and respond to static and dynamic changes in the
level of mechanical stress applied to integrins. |
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