Architecture and mechanical properties of crosslinked Keratin 8/18 networks
Auch gedruckt in der BibliothekW: W-H 14.802
FakultätFakultät für Naturwissenschaften
InstitutionInstitut für Experimentelle Physik
Ressourcen- / MedientypDissertation, Text
Datum der Erstveröffentlichung2016-07-19
The cytoskeleton, which consists of microtubules, actin filaments and intermediate filaments, stabilizes cells under mechanical stress. Especially important for stress resistance is the intermediate filament network. Since cells are very complex systems, it is difficult to obtain detailed knowledge about mechanics and functionality of single cytoskeletal components by only studying complete cells. Therefore, this thesis investigates intermediate filaments, the major contributor to cell rigidity, with the help of in vitro assembled keratin 8/18 networks. In particular the influence of monovalent ions on network stiffness is tested by using KCl and compared to crosslinking mediated by plectin. The results obtained with plectin in vitro are compared to extracted cells from the vulvar carcinoma derived cell line A431 with and without plectin downregulation. Furthermore, the special role of the C-terminal tail domain in network mechanics is examined. All samples are first analysed with electron microscopic methods to characterise the network architecture and subsequently mechanical properties are investigated with passive microrheology. Combining the findings from different methods and samples, a deeper insight in intermediate filament network mechanics is obtained. Setting these results in context with recent advances in other fields of biophysics and cell biology leads to a deeper knowledge of cell behaviour.