Abstract
A stochastic, nonlinear dynamic model is proposed to explain the growth cone at the tip of a cell process, such as a growing axon or dendrite of a neuron. The model explains the outward motion of the tip as an extension of the cytoskeleton, using the actin-myosin system as a molecular motor. The kinetic energy is supplied by heat from ATP hydrolysis in the form of random motion of water molecules embedding the actin-myosin. The mechanical structure is provided by the F-actin macromolecules forming a spiral filament. The myosin heads form a stochastic distribution of small spheres. They are attached by elastic springs to the spiral rods of the myosin filaments. Under thermal agitation the system sustains oscillation, which is directed by the interaction between the myosin heads and the actin filament. As the energy of oscillation is dissipated, the actin filament is moved toward the center of the growth cone. The joint probability density of movement of the actin filament is obtained by solving a non-stationary version of the FPK equation. By incorporating a probability distribution of actin filaments provided by the geometry of the tip, the directed motion of the tip is explained.
Highlights
It is important to understand the mechanism of motion of the growth cone at the tip of an axon, in order to explain how it is accurately directed to its targets in the formation of functional neural networks
It follows that the actin- myosin mechanism is a dissipative, non-equilibrium system feeding on thermal energy, and that the joint probability density is a function of the distributions of displacement and velocity of the molecules
In this paper, according to the theory of molecular machines of the living cell we present a new idea and a new nonlinear mechanical model that can be used to describe why the growth cone can induct the reach of neuronal salience in probabilistic sense
Summary
It is important to understand the mechanism of motion of the growth cone at the tip of an axon, in order to explain how it is accurately directed to its targets in the formation of functional neural networks. The thermal energy serves to expand the center of the growth cone. It follows that the actin- myosin mechanism is a dissipative, non-equilibrium system feeding on thermal energy, and that the joint probability density is a function of the distributions of displacement and velocity of the molecules.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
