Measuring nonequilibrium vesicle dynamics in neurons under tension

Wylie W. Ahmed, Brian J. Williams, Aaron M. Silver, M Taher A Saif

Research output: Contribution to journalArticle

Abstract

Vesicle transport in neurons is a highly complex nonequilibrium process. Their subcellular environment is undergoing constant fluctuations from thermal energy and molecular motors. Vesicle transport is an interplay between random motion (passive) and directed motion (active) driven by molecular motors along cytoskeletal filaments. It has been shown that growth, guidance, and vesicle dynamics of neurons is affected by mechanical tension. Here we present a method to analyze vesicle transport via a temporal Mean Square Displacement (tMSD) analysis while applying mechanical strain to neurons. The tMSD analysis allows characterization of active and passive vesicle motion as well as many other parameters including: power law scaling, velocity, direction, and flux. Our results suggest: (1) The tMSD analysis is able to capture vesicle motion alternating between passive and active states, and indicates that vesicle motion in Aplysia neurons is primarily passive (exhibiting active motion for ∼8% of the time). (2) Under mechanical stretch (increased neurite tension), active transport of vesicles increases to ∼13%, while vesicle velocity remains unchanged. (3) Upon unstretching (decreased tension), the level of active transport returns to normal but vesicle velocity decreases. These results suggest that vesicle transport in neurons is highly sensitive to mechanical stimulation. Our method allows precise characterization of vesicle dynamics in response to applied mechanical strain.

Original languageEnglish (US)
Pages (from-to)570-578
Number of pages9
JournalLab on a Chip
Volume13
Issue number4
DOIs
StatePublished - Feb 21 2013

Fingerprint

Transport Vesicles
Neurons
Active Biological Transport
Scaling laws
Aplysia
Thermal energy
Neurites
Cytoskeleton
Fluxes
Hot Temperature
Growth

ASJC Scopus subject areas

  • Bioengineering
  • Biochemistry
  • Chemistry(all)
  • Biomedical Engineering

Cite this

Measuring nonequilibrium vesicle dynamics in neurons under tension. / Ahmed, Wylie W.; Williams, Brian J.; Silver, Aaron M.; Saif, M Taher A.

In: Lab on a Chip, Vol. 13, No. 4, 21.02.2013, p. 570-578.

Research output: Contribution to journalArticle

Ahmed, Wylie W. ; Williams, Brian J. ; Silver, Aaron M. ; Saif, M Taher A. / Measuring nonequilibrium vesicle dynamics in neurons under tension. In: Lab on a Chip. 2013 ; Vol. 13, No. 4. pp. 570-578.
@article{94d5eea26f3a42bba8e93233944ff322,
title = "Measuring nonequilibrium vesicle dynamics in neurons under tension",
abstract = "Vesicle transport in neurons is a highly complex nonequilibrium process. Their subcellular environment is undergoing constant fluctuations from thermal energy and molecular motors. Vesicle transport is an interplay between random motion (passive) and directed motion (active) driven by molecular motors along cytoskeletal filaments. It has been shown that growth, guidance, and vesicle dynamics of neurons is affected by mechanical tension. Here we present a method to analyze vesicle transport via a temporal Mean Square Displacement (tMSD) analysis while applying mechanical strain to neurons. The tMSD analysis allows characterization of active and passive vesicle motion as well as many other parameters including: power law scaling, velocity, direction, and flux. Our results suggest: (1) The tMSD analysis is able to capture vesicle motion alternating between passive and active states, and indicates that vesicle motion in Aplysia neurons is primarily passive (exhibiting active motion for ∼8{\%} of the time). (2) Under mechanical stretch (increased neurite tension), active transport of vesicles increases to ∼13{\%}, while vesicle velocity remains unchanged. (3) Upon unstretching (decreased tension), the level of active transport returns to normal but vesicle velocity decreases. These results suggest that vesicle transport in neurons is highly sensitive to mechanical stimulation. Our method allows precise characterization of vesicle dynamics in response to applied mechanical strain.",
author = "Ahmed, {Wylie W.} and Williams, {Brian J.} and Silver, {Aaron M.} and Saif, {M Taher A}",
year = "2013",
month = "2",
day = "21",
doi = "10.1039/c2lc41109a",
language = "English (US)",
volume = "13",
pages = "570--578",
journal = "Lab on a Chip - Miniaturisation for Chemistry and Biology",
issn = "1473-0197",
publisher = "Royal Society of Chemistry",
number = "4",

}

TY - JOUR

T1 - Measuring nonequilibrium vesicle dynamics in neurons under tension

AU - Ahmed, Wylie W.

AU - Williams, Brian J.

AU - Silver, Aaron M.

AU - Saif, M Taher A

PY - 2013/2/21

Y1 - 2013/2/21

N2 - Vesicle transport in neurons is a highly complex nonequilibrium process. Their subcellular environment is undergoing constant fluctuations from thermal energy and molecular motors. Vesicle transport is an interplay between random motion (passive) and directed motion (active) driven by molecular motors along cytoskeletal filaments. It has been shown that growth, guidance, and vesicle dynamics of neurons is affected by mechanical tension. Here we present a method to analyze vesicle transport via a temporal Mean Square Displacement (tMSD) analysis while applying mechanical strain to neurons. The tMSD analysis allows characterization of active and passive vesicle motion as well as many other parameters including: power law scaling, velocity, direction, and flux. Our results suggest: (1) The tMSD analysis is able to capture vesicle motion alternating between passive and active states, and indicates that vesicle motion in Aplysia neurons is primarily passive (exhibiting active motion for ∼8% of the time). (2) Under mechanical stretch (increased neurite tension), active transport of vesicles increases to ∼13%, while vesicle velocity remains unchanged. (3) Upon unstretching (decreased tension), the level of active transport returns to normal but vesicle velocity decreases. These results suggest that vesicle transport in neurons is highly sensitive to mechanical stimulation. Our method allows precise characterization of vesicle dynamics in response to applied mechanical strain.

AB - Vesicle transport in neurons is a highly complex nonequilibrium process. Their subcellular environment is undergoing constant fluctuations from thermal energy and molecular motors. Vesicle transport is an interplay between random motion (passive) and directed motion (active) driven by molecular motors along cytoskeletal filaments. It has been shown that growth, guidance, and vesicle dynamics of neurons is affected by mechanical tension. Here we present a method to analyze vesicle transport via a temporal Mean Square Displacement (tMSD) analysis while applying mechanical strain to neurons. The tMSD analysis allows characterization of active and passive vesicle motion as well as many other parameters including: power law scaling, velocity, direction, and flux. Our results suggest: (1) The tMSD analysis is able to capture vesicle motion alternating between passive and active states, and indicates that vesicle motion in Aplysia neurons is primarily passive (exhibiting active motion for ∼8% of the time). (2) Under mechanical stretch (increased neurite tension), active transport of vesicles increases to ∼13%, while vesicle velocity remains unchanged. (3) Upon unstretching (decreased tension), the level of active transport returns to normal but vesicle velocity decreases. These results suggest that vesicle transport in neurons is highly sensitive to mechanical stimulation. Our method allows precise characterization of vesicle dynamics in response to applied mechanical strain.

UR - http://www.scopus.com/inward/record.url?scp=84875786039&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84875786039&partnerID=8YFLogxK

U2 - 10.1039/c2lc41109a

DO - 10.1039/c2lc41109a

M3 - Article

C2 - 23303380

AN - SCOPUS:84875786039

VL - 13

SP - 570

EP - 578

JO - Lab on a Chip - Miniaturisation for Chemistry and Biology

JF - Lab on a Chip - Miniaturisation for Chemistry and Biology

SN - 1473-0197

IS - 4

ER -