3D Structure of Ring-shaped Microtubule Swarms Revealed by High-speed Atomic Force Microscopy

Abstract

Biomolecular motor, microtubule (MT) and kinesin based molecular swarm robots are important due to their applications in cooperative task achievements, while the structural details are still unknown. In this work, high-speed atomic force microscopy was used to observe the MT swarm ring structure at nanometer-level resolution. MTs were observed to pile up in multiple layers to form swarm rings. The number of MTs involved in force generation was estimated which will specifically impact the understanding of the force-generation capability of swarms. The conventional fluorescence observation technique is incapable of revealing the structural details of the microtubule (MT)-kinesin-based swarm ring. We observed the MTs in a swarm ring using high-resolution high-speed atomic force microscopy to understand the assembly and spacial arrangement. The MTs were found to stack in multiple layers instead of a single layer in the swarm structure.