1. Physics of Living Systems
  2. Structural Biology and Molecular Biophysics
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Multi-color fluorescence fluctuation spectroscopy in living cells via spectral detection

  1. Valentin Dunsing  Is a corresponding author
  2. Annett Petrich
  3. Salvatore Chiantia  Is a corresponding author
  1. Universität Potsdam, Germany
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Cite this article as: eLife 2021;10:e69687 doi: 10.7554/eLife.69687

Abstract

Signaling pathways in biological systems rely on specific interactions between multiple biomolecules. Fluorescence fluctuation spectroscopy provides a powerful toolbox to quantify such interactions directly in living cells. Cross-correlation analysis of spectrally separated fluctuations provides information about inter-molecular interactions but is usually limited to two fluorophore species. Here, we present scanning fluorescence spectral correlation spectroscopy (SFSCS), a versatile approach that can be implemented on commercial confocal microscopes, allowing the investigation of interactions between multiple protein species at the plasma membrane. We demonstrate that SFSCS enables cross-talk-free cross-correlation, diffusion and oligomerization analysis of up to four protein species labeled with strongly overlapping fluorophores. As an example, we investigate the interactions of influenza A virus (IAV) matrix protein 2 with two cellular host factors simultaneously. We furthermore apply raster spectral image correlation spectroscopy for the simultaneous analysis of up to four species and determine the stoichiometry of ternary IAV polymerase complexes in the cell nucleus.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1-7. The analysis software is freely available on Github: https://github.com/VaDu8989/SpectralFFS.

The following data sets were generated

Article and author information

Author details

  1. Valentin Dunsing

    Universität Potsdam, Potsdam, Germany
    For correspondence
    valentin.dunsing@gmx.de
    Competing interests
    The authors declare that no competing interests exist.
  2. Annett Petrich

    Universität Potsdam, Potsdam, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Salvatore Chiantia

    Universität Potsdam, Potsdam, Germany
    For correspondence
    chiantia@uni-potsdam.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0791-967X

Funding

Deutsche Forschungsgemeinschaft (254850309)

  • Salvatore Chiantia

Deutsche Forschungsgemeinschaft (INST 336/114-1 FUGG)

  • Salvatore Chiantia

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Ilaria Testa, KTH Royal Institute of Technology, Sweden

Publication history

  1. Received: April 23, 2021
  2. Accepted: September 7, 2021
  3. Accepted Manuscript published: September 8, 2021 (version 1)

Copyright

© 2021, Dunsing et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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Further reading

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