From dynamic live cell imaging to 3D ultrastructure: novel integrated methods for high pressure freezing and correlative light-electron microscopy

PLoS One. 2010 Feb 3;5(2):e9014. doi: 10.1371/journal.pone.0009014.

Abstract

Background: In cell biology, the study of proteins and organelles requires the combination of different imaging approaches, from live recordings with light microscopy (LM) to electron microscopy (EM).

Methodology: To correlate dynamic events in adherent cells with both ultrastructural and 3D information, we developed a method for cultured cells that combines confocal time-lapse images of GFP-tagged proteins with electron microscopy. With laser micro-patterned culture substrate, we created coordinates that were conserved at every step of the sample preparation and visualization processes. Specifically designed for cryo-fixation, this method allowed a fast freezing of dynamic events within seconds and their ultrastructural characterization. We provide examples of the dynamic oligomerization of GFP-tagged myotubularin (MTM1) phosphoinositides phosphatase induced by osmotic stress, and of the ultrastructure of membrane tubules dependent on amphiphysin 2 (BIN1) expression.

Conclusion: Accessible and versatile, we show that this approach is efficient to routinely correlate functional and dynamic LM with high resolution morphology by EM, with immuno-EM labeling, with 3D reconstruction using serial immuno-EM or tomography, and with scanning-EM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • COS Cells
  • Chlorocebus aethiops
  • Electron Microscope Tomography / methods*
  • Freezing
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Green Fluorescent Proteins / ultrastructure
  • Humans
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Microscopy, Confocal / methods*
  • Microscopy, Electron, Scanning
  • Molecular Dynamics Simulation
  • Pressure
  • Protein Tyrosine Phosphatases, Non-Receptor / genetics
  • Protein Tyrosine Phosphatases, Non-Receptor / metabolism
  • Protein Tyrosine Phosphatases, Non-Receptor / ultrastructure
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism*
  • Recombinant Fusion Proteins / ultrastructure*
  • Reproducibility of Results

Substances

  • Luminescent Proteins
  • Recombinant Fusion Proteins
  • Green Fluorescent Proteins
  • MTMR2 protein, human
  • MTMR4 protein, human
  • Protein Tyrosine Phosphatases, Non-Receptor
  • myotubularin