Cytoskeleton dynamics: fluctuations within the network.
Out-of-equilibrium systems, such as the dynamics of a living cytoskeleton (CSK), are inherently noisy with fluctuations arising from the stochastic nature of the underlying biochemical and molecular events. Recently, such fluctuations within the cell were characterized by observing spontaneous nano-scale motions of an RGD-coated microbead bound to the cell surface [Bursac et al., Nat. Mater. 4 (2005) 557-561]. While these reported anomalous bead motions represent a molecular level reorganization (remodeling) of microstructures in contact with the bead, a precise nature of these cytoskeletal constituents and forces that drive their remodeling dynamics are largely unclear. Here, we focused upon spontaneous motions of an RGD-coated bead and, in particular, assessed to what extent these motions are attributable to (i) bulk cell movement (cell crawling), (ii) dynamics of focal adhesions, (iii) dynamics of lipid membrane, and/or (iv) dynamics of the underlying actin CSK driven by myosin motors.
Bursac
Predrag
P
Molecular and Integrative Physiological Sciences, Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115, USA.
Fabry
Ben
B
Trepat
Xavier
X
Lenormand
Guillaume
G
Butler
James P
JP
Wang
Ning
N
Fredberg
Jeffrey J
JJ
An
Steven S
SS
D000199:Actins / Q000378:metabolism; D000818:Animals; D002465:Cell Movement; D002478:Cells, Cultured; D003599:Cytoskeleton / Q000378:metabolism*; D006801:Humans; D008024:Ligands; D009130:Muscle, Smooth / Q000648:ultrastructure*; D009218:Myosins / Q000378:metabolism; D051381:Rats
D000199:Actins; D008024:Ligands; D009218:Myosins