Regensburg 2010 – wissenschaftliches Programm
BP 23.9: Vortrag
Donnerstag, 25. März 2010, 12:30–12:45, H43
Intermediate filament assembly in micro-flow studied by X-ray scattering — •Martha Brennich, Jens Nolting, Christian Dammann, Bernd Nöding, Susanne Bauch, and Sarah Köster — Courant Research Centre Nano-Spectroscopy and X-Ray Imaging, University of Göttingen, Germany
The cytoskeleton, which is responsible for many mechanical properties of the cell, primarily consists of three different types of fibrous proteins: actin filaments, microtubules and intermediate filaments (IFs). The latter comprise a variety of proteins that vary from cell type to cell type. Our work is focused on the hierarchical self-assembly of IF subunits into filaments. We study these processes on the example of vimentin where the assembly can be initiated in vitro by increasing the salt concentration of the solution. Microfluidic tools are used to establish precise pH and salt concentration gradients, wherein the assembly occurs and can be observed in situ. Because of the small channel dimensions and the corresponding laminar flow, the time axis for the assembly process is projected onto a spatial axis along the flow direction and we observe different assembly states by collecting data at different positions in the device. A new type of 3D microfluidic device optimized for small angle X-ray scattering experiments allows us to obtain structural information on the first steps of the vimentin assembly. From the changes in the structural composition we deduce the kinetics of the filament formation and elongation.