Fiber bundles are widely found in nature. They facilitate a multitude of biological functions and exhibit unusual mechanical properties. An example of a fiber bundle in cell biology is the microtubule which is involved in many cell functions. Microtubules are tubular-shaped, formed of small protein filaments whose interactions determine the mechanics of the overall microtubule. Recent studies have provided evidence that this specific molecular architecture leads to unexpected mechanical properties, the most important of which is that they become stiffer against bending as they grow longer. This finding also suggests that the molecular architecture largely determines how fast a bent microtubule relaxes to its equilibrium state. Thus, a systematic study is needed to address the interplay between molecular architecture, mechanics, and dynamical properties over a wide range of filament lengths. In the proposed research, the relaxation of naturally occurring bending deformations of microtubules will be analyzed with high-resolution light microscopy and compared with theoretical models that take the molecular architecture of microtubules into account.
The research will be important for material science and engineering as the knowledge can be used to design materials with novel mechanical properties. More generally a better understanding of multifunctional fiber materials in cells will be obtained. The project will expose students to a rich interplay between scientific fields as diverse as material science and engineering, theoretical physics, physical chemistry, and molecular biology, thereby educating them in an interdisciplinary approach towards research.
