Direct force probe reveals the mechanics of nuclear homeostasis in the mammalian cell
UMass Chan Affiliations
Department of Cell and Developmental BiologyDocument Type
ArticlePublication Date
2015-05-05Keywords
ActinsAnimals
Cell Adhesion
Cell Line, Tumor
Cell Membrane
Cell Nucleus
Cell Survival
Cytoskeleton
Elasticity
Fibroblasts*Gene Expression RegulationGreen Fluorescent Proteins*HomeostasisHumansMiceMicromanipulationMicroscopy, FluorescenceMicrotubulesNIH 3T3 CellsNuclear EnvelopeRNA, Small Interferingcytoskeletonnuclear forcesnuclear mechanicsnuclear positioningnuclear shapeCell Biology
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How cells maintain nuclear shape and position against various intracellular and extracellular forces is not well understood, although defects in nuclear mechanical homeostasis are associated with a variety of human diseases. We estimated the force required to displace and deform the nucleus in adherent living cells with a technique to locally pull the nuclear surface. A minimum pulling force of a few nanonewtons--far greater than typical intracellular motor forces--was required to significantly displace and deform the nucleus. Upon force removal, the original shape and position were restored quickly within a few seconds. This stiff, elastic response required the presence of vimentin, lamin A/C, and SUN (Sad1p, UNC-84)-domain protein linkages, but not F-actin or microtubules. Although F-actin and microtubules are known to exert mechanical forces on the nuclear surface through molecular motor activity, we conclude that the intermediate filament networks maintain nuclear mechanical homeostasis against localized forces.Source
Proc Natl Acad Sci U S A. 2015 May 5;112(18):5720-5. doi: 10.1073/pnas.1502111112. Epub 2015 Apr 21. Link to article on publisher's site.DOI
10.1073/pnas.1502111112Permanent Link to this Item
http://hdl.handle.net/20.500.14038/26489PubMed ID
25901323Related Resources
Link to Article in PubMedRights
Publisher PDF posted as allowed by the publisher's author rights policy at http://www.pnas.org/site/aboutpnas/authorfaq.xhtml.
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