Artificial rotary molecular motors convert energy into controlled motion in a continuous manner. The capability to drive a system out-of-equilibrium with molecular precision offers fascinating prospects to mediate cell behavior as biological systems take advantage of dynamic environments in order to control the biointerface and direct adhesion events and cell fate. Here, we demonstrate that the fate of human bone marrow-derived mesenchymal stem cells (hBM-MSCs) can be regulated by the rotary motion of light-driven molecular motors grafted on surfaces.
We found that the dynamic motion of molecular motors grafted on surfaces is able to direct the fate of hBM-MSCs. hBM-MSCs on the rotary motor surface were more prone to differentiate into osteoblasts, whereas on the static motor surface they tend to better maintain their stemness. We demonstrated that the underlying mechanism is associated with the behavior of initial adsorbed serum albumin (i.e., amount, conformation, and morphology), which is regulated solely by the molecular motion. Unidirectional rotating molecular motors increased the serum albumin adsorption and decreased the α-helix secondary structure, which subsequently affected the adsorbed amount of Fn. The distinct protein adsorption behavior influenced the FA cytoskeleton actin transduction pathway as well as the macroscopic cell adhesion and morphology, evident from studying focal adhesion, filopodia and actin stress fibers, and as a result mediates the fate of hBM-MSCs. Besides providing a unique way to dynamically influence the interaction between surfaces and cells as demonstrated here, the molecular motors based the surface offer numerous opportunities for mechanical stimulation and control of cell fate and responsive biomimetic materials.