Mechanical assessment by magnetocytometry of the cytosolic and cortical cytoskeletal compartments in adherent epithelial cells.
This study aims at quantifying the cellular mechanical properties based on a partitioning of the cytoskeleton in a cortical and a cytosolic compartments. The mechanical response of epithelial cells obtained by magnetocytometry - a micromanipulation technique which uses twisted ferromagnetic beads specifically linked to integrin receptors - was purposely analysed using a series of two Voigt bodies. Results showed that the cortical cytoskeleton has a faster response ( approximately 1 s) than the cytosolic compartment ( approximately 30 s). Moreover, the two cytoskeletal compartments have specific mechanical properties, i.e., the cortical (resp. cytosolic) cytoskeleton has a rigidity in the range: 49-85 Pa (resp.: 74-159 Pa) and a viscosity in the range 5-14 Pa.s (resp.: 593-1534 Pa.s), depending on the level of applied stress. Depolymerising actin-filaments strongly modified these values and especially those of the cytosolic compartment. The structural relevance of this two-compartment partitioning was supported by images of F-actin structure obtained on the same cells.
Laurent
Valérie M
VM
Unité de Recherche de Physiopathologie et Thérapeutique Respiratoires INSERM Unité 492, Faculté de Médecine-Paris XII, 8 rue du Général Sarrail, 94010 Créteil Cedex, France. valerie.laurent@epfl.ch
Planus
Emmanuelle
E
Fodil
Redouane
R
Isabey
Daniel
D
D000199:Actins / Q000032:analysis; D002448:Cell Adhesion / Q000502:physiology; D018929:Cell Culture Techniques / Q000379:methods; D003599:Cytoskeleton / Q000737:chemistry / Q000502:physiology* / Q000648:ultrastructure; D004548:Elasticity; D004847:Epithelial Cells / Q000737:chemistry / Q000502:physiology* / Q000648:ultrastructure; D006801:Humans; D008280:Magnetics; D008846:Micromanipulation / Q000379:methods; D008863:Microspheres; D008954:Models, Biological; D013314:Stress, Mechanical; D014783:Viscosity
D000199:Actins