Selective Assembly and Alignment of Actin Filaments with Desired Polarity on Solid Substrates

We report a new strategy to selectively assemble and align filamentous actin (F-actin) onto desired locations on a solid substrate with a specific structural polarity. In this strategy, biotinylated gelsolin caps the structural minus end of F-actin so that the F-actin binds onto a streptavidin pattern with a specific structural polarity. We also demonstrate that an electric field can be utilized to align bound F-actin along a desired direction. This can be one of the major technical breakthroughs toward the assembly of nanomechanical systems based on myosin biomotors.