CiteULike: dchens Koenderink http://www.citeulike.org/user/dchen/author/Koenderink CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dchen/article/2767406 <i>Physical Review Letters, Vol. 100, No. 11. (2008)</i><br /><br />Biological activity gives rise to nonequilibrium fluctuations in the cytoplasm of cells; however, there are few methods to directly measure these fluctuations. Using a reconstituted actin cytoskeleton, we show that the bending dynamics of embedded microtubules can be used to probe local stress fluctuations. We add myosin motors that drive the network out of equilibrium, resulting in an increased amplitude and modified time dependence of microtubule bending fluctuations. We show that this behavior results from steplike forces on the order of 10 pN driven by collective motor dynamics. Nonequilibrium Microtubule Fluctuations in a Model Cytoskeleton Clifford Brangwynne Gijsje Koenderink Frederick Mackintosh David Weitz doi:10.1103/PhysRevLett.100.118104 Physical Review Letters, Vol. 100, No. 11. (2008) 2008-05-07T21:19:39-00:00 Physical Review Letters 100 11 APS 2008 biology weitz http://www.citeulike.org/user/dchen/article/2688177 <i>Current Opinion in Cell Biology, Vol. 19, No. 1. (February 2007), pp. 101-107.</i><br /><br />To elucidate the dynamic and functional role of a cell within the tissue it belongs to, it is essential to understand its material properties. The cell is a viscoelastic material with highly unusual properties. Measurements of the mechanical behavior of cells are beginning to probe the contribution of constituent components to cell mechanics. Reconstituted cytoskeletal protein networks have been shown to mimic many aspects of the mechanical properties of cells, providing new insight into the origin of cellular behavior. These networks are highly nonlinear, with an elastic modulus that depends sensitively on applied stress. Theories can account for some of the measured properties, but a complete model remains elusive. The cell as a material Karen Kasza Amy Rowat Jiayu Liu Thomas Angelini Clifford Brangwynne Gijsje Koenderink David Weitz doi:10.1016/j.ceb.2006.12.002 Current Opinion in Cell Biology, Vol. 19, No. 1. (February 2007), pp. 101-107. 2008-04-18T15:21:56-00:00 Current Opinion in Cell Biology 19 1 101 107 biology review weitz