A quantitative comparison of single-dye tracking analysis tools using Monte Carlo simulations

PLoS One. 2013 May 30;8(5):e64287. doi: 10.1371/journal.pone.0064287. Print 2013.

Abstract

Single-particle tracking (SPT) is widely used to study processes from membrane receptor organization to the dynamics of RNAs in living cells. While single-dye labeling strategies have the benefit of being minimally invasive, this comes at the expense of data quality; typically a data set of short trajectories is obtained and analyzed by means of the mean square displacements (MSD) or the distribution of the particles' displacements in a set time interval (jump distance, JD). To evaluate the applicability of both approaches, a quantitative comparison of both methods under typically encountered experimental conditions is necessary. Here we use Monte Carlo simulations to systematically compare the accuracy of diffusion coefficients (D-values) obtained for three cases: one population of diffusing species, two populations with different D-values, and a population switching between two D-values. For the first case we find that the MSD gives more or equally accurate results than the JD analysis (relative errors of D-values <6%). If two diffusing species are present or a particle undergoes a motion change, the JD analysis successfully distinguishes both species (relative error <5%). Finally we apply the JD analysis to investigate the motion of endogenous LPS receptors in live macrophages before and after treatment with methyl-β-cyclodextrin and latrunculin B.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Animals
  • Cell Membrane / metabolism*
  • Coloring Agents / metabolism*
  • Lipopolysaccharide Receptors / metabolism
  • Lipopolysaccharides / metabolism
  • Mice
  • Molecular Probe Techniques
  • Monte Carlo Method*
  • Toll-Like Receptor 4 / metabolism

Substances

  • Coloring Agents
  • Lipopolysaccharide Receptors
  • Lipopolysaccharides
  • Toll-Like Receptor 4