Engineering Approaches to Biomolecular Motors

Engineering Approaches to Biomolecular Motors: From in vitro to in vivo Poster Abstracts

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.

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