title: Inhibition of myosin II triggers morphological transition and increased nuclear motility.
abstract: We investigate the effect of myosin II inhibition on cell shape and nuclear motility in cultures of mouse radial glia-like neural progenitor and rat glioma C6 cells. Instead of reducing nucleokinesis, the myosin II inhibitor blebbistatin provokes an elongated bipolar morphology and increased nuclear motility in both cell types. When myosin II is active, time-resolved traction force measurements indicate a pulling force between the leading edge and the nucleus of C6 cells. In the absence of myosin II activity, traction forces during nucleokinesis are diminished below the sensitivity threshold of our assay. By visualizing the centrosome position in C6 cells with GFP-centrin, we show that in the presence or absence of myosin II activity, the nucleus tends to overtake or lag behind the centrosome, respectively. We interpret these findings with the help of a simple viscoelastic model of the cytoskeleton consisting active contractile and passive compressed elements.
authors.affiliation: Department of Biological Physics, Eötvös University, 1117 Budapest, Pa´zma´ny P stny 1A, Hungary.
authors.forename: Bálint
authors.initials: B
authors.lastname: Szabó
authors.forename: Renáta
authors.initials: R
authors.lastname: Ünnep
authors.forename: Károly
authors.initials: K
authors.lastname: Markó
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Környei
authors.forename: Elod
authors.initials: E
authors.lastname: Méhes
authors.forename: András
authors.initials: A
authors.lastname: Czirók
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism* / Q000648:ultrastructure; D016764:Cell Polarity; D048430:Cell Shape; D002478:Cells, Cultured; D018385:Centrosome / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D004548:Elasticity; D006576:Heterocyclic Compounds, 4 or More Rings / Q000494:pharmacology; D051379:Mice; D008870:Microtubules / Q000378:metabolism; D024462:Myosin Type II / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D058953:Neural Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D009457:Neuroglia / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D013314:Stress, Mechanical
chemical_list: D000199:Actins; D006576:Heterocyclic Compounds, 4 or More Rings; C472645:blebbistatin; D024462:Myosin Type II