Mechanical properties of organelles driven by microtubule-dependent molecular motors in living cells

Authors
<div class="autor_fcen" id="1190">Bruno, L.</div>; <div class="autor_fcen" id="7706">Salierno, M.</div>; <div class="autor_fcen" id="9168">Wetzler, D.E.</div>; <div class="autor_fcen" id="2494">Despósito, M.A.</div>; <div class="autor_fcen" id="4951">Levi, V.</div>
Publication Year
2011
Language
English
Format
article
Status
Published version
Description
The organization of the cytoplasm is regulated by molecular motors which transport organelles and other cargoes along cytoskeleton tracks. Melanophores have pigment organelles or melanosomes that move along microtubules toward their minus and plus end by the action of cytoplasmic dynein and kinesin-2, respectively. In this work, we used single particle tracking to characterize the mechanical properties of motor-driven organelles during transport along microtubules. We tracked organelles with high temporal and spatial resolutions and characterized their dynamics perpendicular to the cytoskeleton track. The quantitative analysis of these data showed that the dynamics is due to a spring-like interaction between melanosomes and microtubules in a viscoelastic microenvironment. A model based on a generalized Langevin equation explained these observations and predicted that the stiffness measured for the motor complex acting as a linker between organelles and microtubules is ~ one order smaller than that determined for motor proteins in vitro. This result suggests that other biomolecules involved in the interaction between motors and organelles contribute to the mechanical properties of the motor complex. We hypothesise that the high flexibility observed for the motor linker may be required to improve the efficiency of the transport driven by multiple copies of motor molecules. © 2011 Bruno et al.
Fil:Bruno, L. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Salierno, M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Wetzler, D.E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Despósito, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Levi, V. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Source
PLoS ONE 2011;6(4)
Subject
dynactin
dynein adenosine triphosphatase
kinesin
molecular motor
microtubule associated protein
animal cell
article
cell organelle
cell tracking
controlled study
gene dosage
in vitro study
melanosome
microtubule
molecular dynamics
nonhuman
protein function
protein interaction
protein stiffness
protein transport
quantitative analysis
viscoelasticity
Xenopus laevis
animal
biological model
biomechanics
cell survival
elasticity
mechanics
metabolism
viscosity
Animals
Biomechanics
Cell Survival
Elasticity
Mechanical Processes
Melanosomes
Microtubule-Associated Proteins
Microtubules
Models, Biological
Molecular Motor Proteins
Protein Transport
Viscosity
Xenopus laevis
Access level
Open access
License
http://creativecommons.org/licenses/by/2.5/ar
Repository
Biblioteca Digital (UBA-FCEN)
Institution
Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
OAI Identifier
snrd:HASH01872f8c27feaca6bd786aa5