Structural Rearrangements in CHO Cells After Disruption of Individual Cytoskeletal Elements and Plasma Membrane.
Cellular structural integrity is provided primarily by the cytoskeleton, which comprises microtubules, actin filaments, and intermediate filaments. The plasma membrane has been also recognized as a mediator of physical forces, yet its contribution to the structural integrity of the cell as a whole is less clear. In order to investigate the relationship between the plasma membrane and the cytoskeleton, we selectively disrupted the plasma membrane and each of the cytoskeletal elements in Chinese hamster ovary cells and assessed subsequent changes in cellular structural integrity. Confocal microscopy was used to visualize cytoskeletal rearrangements, and optical tweezers were utilized to quantify membrane tether extraction. We found that cholesterol depletion from the plasma membrane resulted in rearrangements of all cytoskeletal elements. Conversely, the state of the plasma membrane, as assessed by tether extraction, was affected by disruption of any of the cytoskeletal elements, including microtubules and intermediate filaments, which are located mainly in the cell interior. The results demonstrate that, besides the cytoskeleton, the plasma membrane is an important contributor to cellular integrity, possibly by acting as an essential framework for cytoskeletal anchoring. In agreement with the tensegrity model of cell mechanics, our results support the notion of the cell as a prestressed structure.
Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000, Ljubljana, Slovenia. spela.zemljic-jokhadar@mf.uni-lj.si.
Špela Zemljič
ŠZ
Jokhadar
Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000, Ljubljana, Slovenia.
Jure
J
Derganc
D008841:Actin Cytoskeleton / Q000378:metabolism; D000818:Animals; D001696:Biomechanical Phenomena / Q000187:drug effects; D016466:CHO Cells; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D048430:Cell Shape / Q000187:drug effects; D002784:Cholesterol / Q000378:metabolism; D006224:Cricetinae; D003412:Cricetulus; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism; D015739:Nocodazole / Q000494:pharmacology
D002784:Cholesterol; D015739:Nocodazole
Actin filaments; Cholesterol; Membrane reservoir; Microtubules; Tether extraction; Vimentin