Abstract
Localization of messenger ribonucleoproteins (mRNPs) plays an essential role in the regulation of gene expression for long-term memory formation and neuronal development. Knowledge concerning the nature of neuronal mRNP transport is thus crucial for understanding how mRNPs are delivered to their target synapses. Here, we report experimental and theoretical evidence that the active transport dynamics of neuronal mRNPs, which is distinct from the previously reported motor-driven transport, follows an aging Lévy walk. Such nonergodic, transient superdiffusion occurs because of two competing dynamic phases: the motor-involved ballistic run and static localization of mRNPs. Our proposed Lévy walk model reproduces the experimentally extracted key dynamic characteristics of mRNPs with quantitative accuracy. Moreover, the aging status of mRNP particles in an experiment is inferred from the model. This study provides a predictive theoretical model for neuronal mRNP transport and offers insight into the active target search mechanism of mRNP particles in vivo.
Highlights
Localization of messenger ribonucleoproteins plays an essential role in the regulation of gene expression for long-term memory formation and neuronal development
A newly transcribed messenger RNA (mRNA) binds multiple RNA binding proteins (RBPs) to form an messenger ribonucleoproteins (mRNPs), which is subsequently transported into a dendrite
Using a genetically engineered mouse that expresses β-actin mRNA labeled with green fluorescent proteins (GFPs)[11], we imaged individual β-actin mRNP particles in hippocampal neurons using wide-field fluorescence microscopy
Summary
Localization of messenger ribonucleoproteins (mRNPs) plays an essential role in the regulation of gene expression for long-term memory formation and neuronal development. With the help of single-particle tracking techniques[30,31], it was shown that some biological superdiffusions such as motordriven active transport in the cytoplasm[32,33] and swarming bacteria migration[34] exhibit patterns of Lévy walks in the sense that their flight length distribution or the velocity autocorrelation decays following a (truncated) power-law. To the best of our knowledge, this report describes the first observation of an in vivo molecular transport process with superdiffusive characteristics that are consistent with an aging Lévy walk. This process belongs to an extended Lévy walk model, allowing a rest period between the successive flights. In the neuronal mRNP motion studied here, we find that this type of Lévy walk process emerges because of the bidirectional a Neuron
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.
