Growth and Elasticity of Mechanically-Created Neurites

TL;DR

This paper presents a morphoelasticity-based model for neurite growth under elastic deformation, fitting experimental data to reveal growth dynamics and establish limits on growth rates.

Contribution

It introduces a novel morphoelasticity framework for modeling neurite growth in response to elastic forces, with experimentally fitted parameters.

Findings

Growth time constant of 0.009 s$^{-1}$ similar to actin diffusion rate

Characterized neurite growth kinematics under mechanical deformation

Established new limits on neurite growth rate

Abstract

Working in the framework of morphoelasticity, we develop a model of neurite growth in response to elastic deformation. We decompose the applied stretch into an elastic component and a growth component, and adopt an observationally-motivated model for the growth law. We then compute the best-fit model parameters by fitting to force-extension curves from measurements of constant-speed uniaxial deformations of mechanically-induced neurites of rat hippocampal neurons. We find a time constant for the growth law of 0.009~s$^{-1}$, similar to the diffusion rate of actin in a cell. Our results characterize the kinematics of neurite growth and establish new limits on the growth rate of neurites.