Spontaneously Beating Biomimetic Structures

The propulsion of motile cells such as sperms and the transport of fluids on cell surfaces rely on oscillatory bending of cellular appendages that can perform periodic oscillations. These structures are flagella and cilia. Their beating is driven by the interaction between microtubules and motor proteins and the mechanism regulating this is still a puzzle. One approach to address this issue is the assembling of synthetic minimal systems by using natural building blocks, e.g., microtubules and kinesin motors, which undergo persistent oscillation in the presence of ATP. An example of an autonomous molecular system is reported in this chapter. It dynamically self-organizes through its elasticity and the interaction with the environment represented by the active forces exerted by motor proteins. The resulting motion resembles the beating of sperm flagella. Assembling such minimal systems able to mimic the behavior of complex biological structures might help to unveil basic mechanisms underlying the beating of natural cilia and flagella.The author also acknowledges support from the MaxSynBio Consortium which is jointly funded by the Federal Ministry of Education and Research of Germany and the Max Planck Society and from the Volkswagen Stiftung ("Experiment!")