Formation of Force Conduits Give Rise to Mechanical Self-Organization Across Microscopic Length Scales

Mechanical self-organization is uniquely found in cells, which organize forces from nanometer to micron length scales with remarkable precision to perform functions like locomotion and cell division. Presently, we are unable to design systems with similar capabilities due to a lack of governing principles for mechanical self-organization. Here, we identify a fundamental mechanism of mechanical self-organization in a minimal biochemical system we re-engineered. We find that forces can be controlled across length scales through the self-organization of structures that act as force conduits. The system contains filaments and light controlled molecular motors that, when activated, form pairs and pull on adjacent filaments. We show that, within localized regions of light, filaments organize into radially aligned asters. Furthermore, asters generate piconewton pulling forces when linked together with light, where the vectors of the pulling forces are determined by both the spatial arrangement of the asters and the geometry of the light that links them. Using the properties of aster interactions, we design and implement schemes for force-actuated logic gates and micron scale control over the transport of beads, which may be further developed to build adaptive micron-scale machines.