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Engineering Approaches to Biomolecular Motors: From in vitro to in vivo Poster Abstracts
48
19-POS
Board 19
Simulating Motor Protein-based Microtransporters
Takahiro Nitta
, Koki Kawauchi, Yuki Ishigure.
Gifu University, Gifu, Gifu, Japan.
Motor proteins, such as myosin and kinesin, are attractive motive powers for nanoscale
engineering. Integration of the motor proteins may offer new driving methods of microdevices,
such as MEMS and biosensors. In pursuing the integration, gliding assay serves as a basis, where
cytoskeletal filaments glide over surfaces covered with their associated motor proteins. In order
to design microdevices integrated with motor proteins, by developing and using a computer
simulation, we investigated the detail mechanisms of the gliding movements.
Cytoskeletal filaments were modeled as inextensible elastic rods. Time evolutions of
conformations of the filaments were computed with a Brownian dynamics simulation. Kinesin
and myosin motors were modeled as linear springs. Once bound, motor heads were assumed to
move toward designated ends of the cytoskeletal filaments. This led that the filaments were
propelled toward the opposite direction. In addition, normal forces were applied when the
filaments collided against the microfabricated guiding walls and the track surfaces. The filaments
were also subjected to external forces. The external forces induced by electric field and fluid
flow are used for directing gliding movements of the filaments.
As well as reproducing previous experimental results, the simulation revealed detail mechanisms
of the gliding movements of the filaments. For example, at chemical edges, zipping of motor
proteins located at the edges was found to occur. And, under strong external forces, filaments
were found to be detached from the leading and trailing ends of cytoskeletal filaments. Such
findings were difficult to obtain in experiments due to their limited spatial and temporal
resolutions.
In summary, our simulation study revealed the detail mechanisms of the gliding movements.
Insights obtained here would be useful in designing microdevices integrated with motor proteins.