Accounting for limited detection efficiency and localization precision in cluster analysis in single molecule localization microscopy

PLoS One. 2015 Mar 20;10(3):e0118767. doi: 10.1371/journal.pone.0118767. eCollection 2015.

Abstract

Single Molecule Localization Microscopy techniques like PhotoActivated Localization Microscopy, with their sub-diffraction limit spatial resolution, have been popularly used to characterize the spatial organization of membrane proteins, by means of quantitative cluster analysis. However, such quantitative studies remain challenged by the techniques' inherent sources of errors such as a limited detection efficiency of less than 60%, due to incomplete photo-conversion, and a limited localization precision in the range of 10-30 nm, varying across the detected molecules, mainly depending on the number of photons collected from each. We provide analytical methods to estimate the effect of these errors in cluster analysis and to correct for them. These methods, based on the Ripley's L(r) - r or Pair Correlation Function popularly used by the community, can facilitate potentially breakthrough results in quantitative biology by providing a more accurate and precise quantification of protein spatial organization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cluster Analysis
  • Computer Simulation
  • Image Processing, Computer-Assisted
  • Limit of Detection
  • Microscopy / methods*

Grants and funding

AS was funded by a Swiss National Competence Center for Biomedical Imaging PhD fellowship. JU was supported by the ERC Advanced Grant—SPARSAM No. 247006. AR acknowledges financial support by FNS grants No. 200021-125319 and No. 200021-132206. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.