Regensburg 2019 – wissenschaftliches Programm

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

BP: Fachverband Biologische Physik

BP 6: Poster I

BP 6.55: Poster

Montag, 1. April 2019, 17:30–19:30, Poster B2

Ion Depending Stress-strain Behavior and Interaction of Intermediate Filaments — Anna Schepers, •Charlotta Lorenz, Johanna Block, Julia Kraxner, and Sarah Köster — Institute for X-Ray Physics, Georg-August-Universität, Göttingen, Germany

The cytoskeleton, consisting of microtubules, actin filaments and intermediate filaments (IFs), is essential for the survival of the cell. Only intermediate filaments are expressed in a cell-type specific manner. Therefore, they are ideal candidates to tune the stability and mechanics of a cell to the environment and requirements. In cells, IFs usually form networks which have been thoroughly studied in vitro by rheology. The properties of single filaments, but also the network structure itself, influence the results derived from rheology. To decouple these two effects, we measure the interaction of two single vimentin IFs with optical trapping in combination with microfluidics and fluorescence microscopy. The interactions between IFs depends on the concentration and ionic strength of surrounding ions. We study how these ions influence the interactions and the stress-strain behavior of single filaments. Thus, we also quantify the effect of ion addition to single vimentin and keratin IFs. We suggest that the cooperativity between monomers within the IF is enhanced upon ion addition, which can be modeled theoretically. Results from a Monte-Carlo simulation support our model qualitatively.