title: Effects of cytoskeletal drugs on actin cortex elasticity.
abstract: Mechanical properties of cells are known to be influenced by the actin cytoskeleton. In this article, the action of drugs that interact with the actin cortex is investigated by tether extraction and rheology experiments using optical tweezers. The influences of Blebbistatin, Cytochalasin D and Jasplakinolide on the cell mechanical properties are evaluated. The results, in contradiction to current views for Jasplakinolide, show that all three drugs and treatments destabilize the actin cytoskeleton, decreasing the cell membrane tension. The cell membrane bending modulus increased when the actin cytoskeleton was disorganized by Cytochalasin D. This effect was not observed for Blebbistatin and Jasplakinolide. All drugs decreased by two-fold the cell viscoelastic moduli, but only Cytochalasin D was able to alter the actin network into a more fluid-like structure. The results can be interpreted as the interplay between the actin network and the distribution of myosins as actin cross-linkers in the cytoskeleton. This information may contribute to a better understanding of how the membrane and cytoskeleton are involved in cell mechanical properties, underlining the role that each one plays in these properties.
authors.affiliation: LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-972, Brazil.
authors.forename: Yareni A
authors.initials: YA
authors.lastname: Ayala
authors.affiliation: LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil.
authors.forename: Bruno
authors.initials: B
authors.lastname: Pontes
authors.affiliation: James Franck Institute, Institute for Biophysical Dynamics and Physics Department, University of Chicago, Chicago, IL 60637,United States.
authors.forename: Barbara
authors.initials: B
authors.lastname: Hissa
authors.affiliation: LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil.
authors.forename: Ana Carolina M
authors.initials: AC
authors.lastname: Monteiro
authors.affiliation: LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil.
authors.forename: Marcos
authors.initials: M
authors.lastname: Farina
authors.affiliation: LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, RJ 20231-092, Brazil.
authors.forename: Vivaldo
authors.initials: V
authors.lastname: Moura-Neto
authors.affiliation: LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-972, Brazil. Electronic address: nathan@if.ufrj.br.
authors.forename: Nathan B
authors.initials: NB
authors.lastname: Viana
authors.affiliation: LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-972, Brazil.
authors.forename: H Moysés
authors.initials: HM
authors.lastname: Nussenzveig
mesh_terms: D008841:Actin Cytoskeleton / Q000737:chemistry / Q000187:drug effects* / Q000648:ultrastructure; D000818:Animals; D001696:Biomechanical Phenomena; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects / Q000648:ultrastructure; D015638:Cytochalasin D / Q000494:pharmacology*; D047630:Depsipeptides / Q000494:pharmacology*; D004548:Elasticity / Q000187:drug effects; D006576:Heterocyclic Compounds, 4 or More Rings / Q000494:pharmacology*; D006801:Humans; D051379:Mice; D009218:Myosins / Q000737:chemistry*; D041681:NIH 3T3 Cells; D052898:Optical Tweezers; D012212:Rheology; D014783:Viscosity / Q000187:drug effects
chemical_list: D047630:Depsipeptides; D006576:Heterocyclic Compounds, 4 or More Rings; C057531:jasplakinolide; C472645:blebbistatin; D015638:Cytochalasin D; D009218:Myosins
keywords: Cell viscoelasticity; Membrane mechanical properties; Membrane-cortex complex; Optical tweezers; Rheology