title: Cells as active particles in asymmetric potentials: motility under external gradients.
abstract: Cell migration is a crucial event during development and in disease. Mechanical constraints and chemical gradients can contribute to the establishment of cell direction, but their respective roles remain poorly understood. Using a microfabricated topographical ratchet, we show that the nucleus dictates the direction of cell movement through mechanical guidance by its environment. We demonstrate that this direction can be tuned by combining the topographical ratchet with a biochemical gradient of fibronectin adhesion. We report competition and cooperation between the two external cues. We also quantitatively compare the measurements associated with the trajectory of a model that treats cells as fluctuating particles trapped in a periodic asymmetric potential. We show that the cell nucleus contributes to the strength of the trap, whereas cell protrusions guided by the adhesive gradients add a constant tunable bias to the direction of cell motion.
authors.affiliation: Laboratory of Cell Physics ISIS/IGBMC, CNRS UMR 7006 and University of Strasbourg, Strasbourg, France; Development and Stem Cells Program, IGBMC, CNRS UMR 7104, INSERM (U964) and University of Strasbourg, Illkirch, France; Nanobioengineering Group, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Comelles
authors.affiliation: Laboratory of Cell Physics ISIS/IGBMC, CNRS UMR 7006 and University of Strasbourg, Strasbourg, France; Development and Stem Cells Program, IGBMC, CNRS UMR 7104, INSERM (U964) and University of Strasbourg, Illkirch, France.
authors.forename: David
authors.initials: D
authors.lastname: Caballero
authors.affiliation: Laboratoire de Physique Théorique de la Matière Condensée, CNRS UMR 7600, Université Pierre et Marie Curie, Paris, France; Laboratoire Jean Perrin, CNRS FRE 3231, Université Pierre et Marie Curie, Paris, France.
authors.forename: Raphaël
authors.initials: R
authors.lastname: Voituriez
authors.affiliation: Biomimetic Systems for Cell Engineering, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain; Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Zaragoza, Spain.
authors.forename: Verónica
authors.initials: V
authors.lastname: Hortigüela
authors.affiliation: Laboratory of Cell Physics ISIS/IGBMC, CNRS UMR 7006 and University of Strasbourg, Strasbourg, France; Development and Stem Cells Program, IGBMC, CNRS UMR 7104, INSERM (U964) and University of Strasbourg, Illkirch, France.
authors.forename: Viktoria
authors.initials: V
authors.lastname: Wollrab
authors.affiliation: Laboratory of Cell Physics ISIS/IGBMC, CNRS UMR 7006 and University of Strasbourg, Strasbourg, France; Development and Stem Cells Program, IGBMC, CNRS UMR 7104, INSERM (U964) and University of Strasbourg, Illkirch, France.
authors.forename: Amélie Luise
authors.initials: AL
authors.lastname: Godeau
authors.affiliation: Nanobioengineering Group, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain; Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Zaragoza, Spain; Department of Electronics, University of Barcelona, Barcelona, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Samitier
authors.affiliation: Biomimetic Systems for Cell Engineering, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain; Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Zaragoza, Spain; Department of Electronics, University of Barcelona, Barcelona, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Martínez
authors.affiliation: Laboratory of Cell Physics ISIS/IGBMC, CNRS UMR 7006 and University of Strasbourg, Strasbourg, France; Development and Stem Cells Program, IGBMC, CNRS UMR 7104, INSERM (U964) and University of Strasbourg, Illkirch, France. Electronic address: riveline@unistra.fr.
authors.forename: Daniel
authors.initials: D
authors.lastname: Riveline
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002465:Cell Movement; D002467:Cell Nucleus / Q000378:metabolism; D051379:Mice; D008954:Models, Biological; D041681:NIH 3T3 Cells