Berlin 2012 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 27: Posters: Cytoskeletal Filaments

BP 27.15: Poster

Donnerstag, 29. März 2012, 17:30–19:30, Poster A

Diameter of Keratin 8/18 — •Ines Martin¹, Anke Leitner¹, Masoud Amirkhani¹, Vladislav Krzyzanek², Michael Beil³, Harald Herrmann⁴, Paul Walther⁵, and Othmar Marti¹ — ¹Institute for Experimental Physics, Ulm University, Ulm — ²Institute of Medical Physics and Biophysics, Münster University, Münster — ³Internal Medicine I, Ulm University, Ulm — ⁴Division of Molecular Genetics, German Cancer Research Center, Heidelberg — ⁵Central Facility of Electron Microscopy, Ulm University, Ulm

The cytoskeleton of epithelial cells consists of three types of filament systems: microtubules, intermediate filaments (IFs) and actin filaments. In our work, we have a closer look at intermediate filaments, which are responsible for the stiffness of cells and responses to mechanical stimuli.

Because of their heterogeneous nature, it is not exactly known how IFs are arranged over their cross-section, even though some measurements of diameter, mass per length and cross-section exist. Therefore we compared the diameter of filaments with different techniques: Transmission Electron Microscopy with negative staining, Scanning Electron Microscopy of freeze-dried samples with tungsten coating, Scanning Transmission Electron Microscopy (STEM) with and without glutaraldehyde fixation and Small Angle X-ray Scattering (SAXS). Additionally we studied the behavior of Keratin 8/18 adsorbed on a substrate with SEM of freeze-dried samples. Here we could see flattening of some of the filaments, from which one can conclude in agreement with STEM data that the IFs are not very densely packed.