Visualizing protein partnerships in living cells and organisms

Curr Opin Chem Biol. 2011 Dec;15(6):781-8. doi: 10.1016/j.cbpa.2011.10.024. Epub 2011 Nov 19.


In recent years, scientists have expanded their focus from cataloging genes to characterizing the multiple states of their translated products. One anticipated result is a dynamic map of the protein association networks and activities that occur within the cellular environment. While in vitro-derived network maps can illustrate which of a multitude of possible protein-protein associations could exist, they supply a falsely static picture lacking the subtleties of subcellular location (where) or cellular state (when). Generating protein association network maps that are informed by both subcellular location and cell state requires novel approaches that accurately characterize the state of protein associations in living cells and provide precise spatiotemporal resolution. In this review, we highlight recent advances in visualizing protein associations and networks under increasingly native conditions. These advances include second generation protein complementation assays (PCAs), chemical and photo-crosslinking techniques, and proximity-induced ligation approaches. The advances described focus on background reduction, signal optimization, rapid and reversible reporter assembly, decreased cytotoxicity, and minimal functional perturbation. Key breakthroughs have addressed many challenges and should expand the repertoire of tools useful for generating maps of protein interactions resolved in both time and space.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Cross-Linking Reagents / chemistry
  • Fluorescence Resonance Energy Transfer
  • Fluorescent Dyes / chemical synthesis*
  • Fluorescent Dyes / metabolism
  • Microscopy, Fluorescence
  • Photochemical Processes / radiation effects
  • Photochemistry / methods*
  • Protein Interaction Mapping / methods*
  • Protein Interaction Maps
  • Proteins / analysis*
  • Proteins / chemistry
  • Proteins / metabolism
  • Staining and Labeling / methods*
  • Ultraviolet Rays


  • Cross-Linking Reagents
  • Fluorescent Dyes
  • Proteins