title: Direct observation of nanomechanical properties of chromatin in living cells.
abstract: Precise manipulation of nanometer-sized magnetic particles using magnetic tweezers has yielded insights into the rheology of the cell cytoplasm. We present first results using this approach to study the nanomechanics of the cell nucleus. Using a custom-designed micro-magnetic-tweezers instrument, we can achieve sufficiently high magnetic forces enabling the application and measurement of controlled distortion of the internal nuclear structure on the nanometer scale. We precisely measure the elasticity and viscosity inside the nucleus of living HeLa cells. The high value of the Young's modulus (Y = 2.5 x 10(2) Pa) measured relative to the cytoplasm is explained by a large-scale model for in vivo chromatin structure using a polymer network model.
authors: Biophysical Engineering, Faculty of Science and Technology, Institute for Biomedical Technology (BMTI), University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
authors: Anthony H B
authors: AH
authors: de Vries
authors: Bea E
authors: BE
authors: Krenn
authors: Roel
authors: R
authors: van Driel
authors: Vinod
authors: V
authors: Subramaniam
authors: Johannes S
authors: JS
authors: Kanger
mesh_terms: D002843:Chromatin / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D036103:Nanotechnology
chemical_list: D002843:Chromatin