Multi-scale Simulations of Soft Elasticity of the Stem Cell and

advertisement
Multi-scale Simulations of Soft Elasticity of the Stem Cell and
Its Contact/Focal Adhesion with Extra-cellular Environments
University of California at Berkeley
Shaofan Li
The latest discovery in cellular and molecular biology is that the
fate or lineage specification of stem cells depend sensitively on
both the rigidity as well as surface micro-structures of the
extra-cellular environment. For example,Engler et al [2006]
reported that matrix elasticity directs stem cell lineage specification.
The ability of the cell to sense the environmental mechanical stimulus
and subsequently to mediate its own coordinated responses is called
Mechanotransduction.
The exact molecular mechanism for mechanotransduction to stem
cell lineage specification is unknown, and it currently is under active
investigation. The objectives of this project are: (1) establishing a
Predictive modeling paradigm that can help us understand biomechanics
and biophysics the focal adhesion of stem cell, (2) to explain and
to elucidate protein conformational changes and binding affinity
changes in response to external forces, external ligand perturbations,
and mechanical properties of external environment.
Even-Ram, S. et al. [2006] Cell and
Engler et al. [2006] Cell
Microstructures of actin in cells and mesgen in nematic liquid crystals
By using a multi-scale approach, we propose a soft elasticity
coarse-grained model that combines modeling methods in
different scales to study this problem, including molecular
dynamics, implicit solvent model,and finite element method
of contact mechanics .
Liquid crystal elastomer cell model and its finite element
Simulation.
The basic hypothesis of our approach is: (1) cells including
stem cells may be modeled as a special type of liquid crystal
elastomer, (2) the cell focal adhesion is induced from contact
phase-transformation, and (3) the stem cell lineage specification
may be explained by contact induced changes in conformation
of protein as well as structural change in cytoskeloton of
the stem cell.
Different surface elastic stiffness induce different
conformation structures as well as global cell structures.
External Research Initiative
Supported by
External Research
2008
Download