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CPP: Chemische Physik und Polymerphysik
CPP 22: SYMPOSIUM Microfluidics II: Soft objects in flow, open geometries
CPP 22.4: Vortrag
Donnerstag, 30. März 2006, 15:00–15:15, ZEU 160
Freely suspended actin cortex models in a controlled microfluidic environment — •Tamas Haraszti1,2, Simon Schulz1,2, Wouter Roos1,2, Christian Schmitz1,2, Jens Ulmer1,2, Stefan Gräter1,2, and Joachim Spatz1,2 — 1Max-Planck-Institute for Metals Research, Department New Materials & Biosystems, Heisenbergstr. 3, D-70569 Stuttgart — 2Biophysical Chemistry, University of Heidelberg, INF 253, D-69120 Heidelberg
Arrays of pillars, microfabricated in PDMS, are constructed to serve as a template for mimicking the actin cortex of cells. The three-dimensional template surface prevents confinement effect on the actin filaments hanging between pillars at a height of about 10 microns. A special flow-cell design enables applying flow -an external driving force- around the network of actin. This unique experimental system opens new possibilities, for example to study the mechanics of two-dimensional actin networks as a function of actin-crosslinkers, to observe the active diffusion of molecular motors operating on pending networks and to investigate the alternations in the transport of microscopic particles, coated by different proteins, along these actin cortex models under the drag of flow.
Such transport problems are studies of tracks and external driving forces (motors, flow) on a statistical process under the influence of order and randomness along two-dimensional networks isolated from the complicated and undetermined cellular environment. The filaments are visualized by fluorescent optical microscopy, and their stiffness can be tuned by bundling of actin filaments through various cross-linkers.