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BP: Fachverband Biologische Physik
BP 9: Physics of Cells I
BP 9.6: Vortrag
Dienstag, 23. März 2010, 11:15–11:30, H43
Shell-String Model of Global Cell Motions, Intracellular Trafficking and Phagocytosis — •Erich Sackmann1, Felix Keber2, and Doris Heinrich2 — 1Biophysik E22, Physik Department, TU München, Germany — 2Fakultät für Physik und CeNS, LMU München, Germany
The survival of cells depends on the ongoing intracellular motions and the rapid reorganisation of intracellular macromolecular scaffolds. Thus, the cytoplasmic space is explored by superpositions of directed transport along and by random walks between microtubules. Further, cell locomotion and phagocytosis are driven by actin gelation waves. This requires cells to combine a high degree of plasticity of the intracellular space with mechanical robustness. We first provide evidence that this astonishing mechanical robustness can be explained in terms of dynamic coupling of the microtubule aster to the actin cortex. Large forces in the nN range are balanced by coupling of the microtubules to actin gelation waves rather than cellular micromuscles. Second, we show that rapid global shape changes, associated with locomotion and phagocytosis, are driven by solitary actin gelation waves acting as travelling force fields. We finally present a model explaining the travelling force field in terms of the synchronous motion of signalling lipids with adhesion domains spreading on surfaces.