DFG Priority Program SPP 1164
Nano- & Microfluidics:
Bridging the Gap between
Molecular Motion and Continuum Flow
Hydrodynamic manipulation of active transport along action cortex models
| Project Leader: | Prof. Dr. Joachim Spatz Ruprecht-Karls-Univesität Heidelberg Physikalisch-Chemisches Institut Heidelberg |
| together with: | Dr. Tamas Haraszti Ruprecht-Karls-Universität Heidelberg Physikalisch-Chemisches Institut Heidelberg |
Summary
We aim to understand how active transport along two-dimensional,
semi-flexible polymer networks is mediated by flow. In particular, the
investigations will focus on twodimensional networks of actin filaments
(F-actin), F-actin bundles and microtubule. These structures mimic
important transport systems in cells such as the actin cortex of
spindle formation. We will make use of our two micromechanical tolls,
i.e. micropillar arrays and Dynamic Holographic Optical Tweezers (DHOT)
in slim microfluidic devices, which engineer the construction of
filament networks and allow for quantitative evaluation of the
hydrodynamic impact on filament network responses. These filament
network models are of extreme biological interest, can be easily
visualized by fluorescent optical microscopy, and their stiffness can
be tuned by bundling of the actin filaments to one another. Most
importantly, actin filaments and microtubule act as tracks for guiding
active transport of cargo such as organelles or microspheres by
molecular motors.
We will explore further how twodimensional actin networks at pillar interfaces or with the help of DHOT are constructed in flow and how their conformations are manipulated after network assembly. Filament bending instabilities and dynamic responses under confined flow situations will be studied quantitatively. Modification of transport of micro- and nanoscopic colloids as well as of Factin bundles with and without motors along these model networks under the drag of flow will then be studied. The transport problems suggested are biomimetic studies of the influence of order and randomness along two-dimensional networks of tracks and external driving forces (motors, flow) on a statistical process isolated from the complicated and undetermined cellular environment.
Ultimately, we will use our models to investigate a variety of interesting questions that cover issues in hydrodynamics, polymer physics (confinement of actin solutions in flow), biology (actin cortex and cellular transport mechanisms in flow) and statistical physics (polymer conformations in flow, statistics of transport on a partially disordered network).
We will explore further how twodimensional actin networks at pillar interfaces or with the help of DHOT are constructed in flow and how their conformations are manipulated after network assembly. Filament bending instabilities and dynamic responses under confined flow situations will be studied quantitatively. Modification of transport of micro- and nanoscopic colloids as well as of Factin bundles with and without motors along these model networks under the drag of flow will then be studied. The transport problems suggested are biomimetic studies of the influence of order and randomness along two-dimensional networks of tracks and external driving forces (motors, flow) on a statistical process isolated from the complicated and undetermined cellular environment.
Ultimately, we will use our models to investigate a variety of interesting questions that cover issues in hydrodynamics, polymer physics (confinement of actin solutions in flow), biology (actin cortex and cellular transport mechanisms in flow) and statistical physics (polymer conformations in flow, statistics of transport on a partially disordered network).