Anomalous Dynamics of in Vivo Cargo Delivery by Motor Protein Multiplexes

J Phys Chem Lett. 2019 Jun 6;10(11):3071-3079. doi: 10.1021/acs.jpclett.9b01106. Epub 2019 May 23.

Abstract

Vesicle transport conducted by motor protein multiplexes (MPMs), which is ubiquitous among eukaryotes, shows anomalous and stochastic dynamics qualitatively different from the dynamics of thermal motion and artificial active matter; the relationship between in vivo vesicle-delivery dynamics and the underlying physicochemical processes is not yet quantitatively understood. Addressing this issue, we perform accurate tracking of individual vesicles, containing upconverting nanoparticles, transported by kinesin-dynein-multiplexes along axonal microtubules. The mean-square-displacement of vesicles along the microtubule exhibits unusual dynamic phase transitions that are seemingly inconsistent with the scaling behavior of the mean-first-passage time over the travel length. These paradoxical results and the vesicle displacement distribution are quantitatively explained and predicted by a multimode MPM model, developed in the current work, where ATP-hydrolysis-coupled motion of MPM has both unidirectional and bidirectional modes.

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Axonal Transport
  • Biological Transport, Active
  • Cell Line
  • Dyneins / metabolism*
  • Humans
  • Hydrolysis
  • Kinesins / metabolism*
  • Kinetics
  • Microtubules / metabolism
  • Models, Biological
  • Multivesicular Bodies / metabolism*
  • Nanoparticles / metabolism

Substances

  • Adenosine Triphosphate
  • Dyneins
  • Kinesins