title: Ultra-soft cantilevers and 3-D micro-patterned substrates for contractile bundle tension measurement in living cells.
abstract: Actin-myosin microfilament bundles or stress-fibers are the principal tension-generating structures in the cell. Their mechanical properties are critical for cell shape, motion, and interaction with other cells and extracellular matrix, but were so far difficult to access in a living cell. Here we propose a micro-fabricated two-component setup for direct tension measurement on a peripheral bundle within an intact cell. We used 3-D substrates made of silicon elastomer to elevate the cell making the filament bundle at its border accessible from the side, and employed an ultra-soft (spring constant 0.78 nN μm(-1)) epoxy-based cantilever for mechanical probing. With this setup we were able for the first time to measure the tension in peripheral actin bundles in living primary fibroblasts spread on a rigid substrate.
authors.affiliation: Laboratory of Cell Biophysics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. niccolo.piacentini@epfl.ch.
authors.forename: Niccolò
authors.initials: N
authors.lastname: Piacentini
authors.forename: Alexander B
authors.initials: AB
authors.lastname: Verkhovsky
authors.forename: Chiara
authors.initials: C
authors.lastname: Gabella
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Meister
authors.forename: Benoît
authors.initials: B
authors.lastname: Vianay
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism*; D000818:Animals; D018929:Cell Culture Techniques / Q000295:instrumentation / Q000379:methods; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000737:chemistry*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D009218:Myosins / Q000378:metabolism*; D051381:Rats; D012826:Silicone Elastomers / Q000737:chemistry*
chemical_list: D012826:Silicone Elastomers; D009218:Myosins