1. Cell Biology
  2. Physics of Living Systems
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Correlative all-optical quantification of mass density and mechanics of sub-cellular compartments with fluorescence specificity

  1. Raimund Schlüßler  Is a corresponding author
  2. Kyoohyun Kim  Is a corresponding author
  3. Martin Nötzel
  4. Anna Taubenberger
  5. Shada Abuhattum
  6. Timon Beck
  7. Paul Müller
  8. Shovamaye Maharana
  9. Gheorghe Cojoc
  10. Salvatore Girardo
  11. Andreas Hermann
  12. Simon Alberti
  13. Jochen Guck  Is a corresponding author
  1. Technische Universität Dresden, Germany
  2. Max Planck Institute for the Science of Light, Germany
  3. University of Rostock, Germany
Research Article
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Cite this article as: eLife 2022;11:e68490 doi: 10.7554/eLife.68490

Abstract

Quantitative measurements of physical parameters become increasingly important for understanding biological processes. Brillouin microscopy (BM) has recently emerged as one technique providing the 3D distribution of viscoelastic properties inside biological samples - so far relying on the implicit assumption that refractive index (RI) and density can be neglected. Here, we present a novel method (FOB microscopy) combining BM with optical diffraction tomography and epi-fluorescence imaging for explicitly measuring the Brillouin shift, RI and absolute density with specificity to fluorescently labeled structures. We show that neglecting the RI and density might lead to erroneous conclusions. Investigating the nucleoplasm of wild-type HeLa cells, we find that it has lower density but higher longitudinal modulus than the cytoplasm. Thus, the longitudinal modulus is not merely sensitive to the water content of the sample - a postulate vividly discussed in the field. We demonstrate the further utility of FOB on various biological systems including adipocytes and intracellular membraneless compartments. FOB microscopy can provide unexpected scientific discoveries and shed quantitative light on processes such as phase separation and transition inside living cells.

Data availability

The data sets generated during and/or analyzed during the current study are available from figshare under the following link: https://doi.org/10.6084/m9.figshare.c.5347778

The following data sets were generated

Article and author information

Author details

  1. Raimund Schlüßler

    Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
    For correspondence
    raimund.schluessler@tu-dresden.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3752-2382
  2. Kyoohyun Kim

    Biological Optomechanics, Max Planck Institute for the Science of Light, Erlangen, Germany
    For correspondence
    kyoohyun.kim@mpl.mpg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1808-775X
  3. Martin Nötzel

    Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6442-9899
  4. Anna Taubenberger

    Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Shada Abuhattum

    Biological Optomechanics, Max Planck Institute for the Science of Light, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Timon Beck

    Biological Optomechanics, Max Planck Institute for the Science of Light, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. Paul Müller

    Biological Optomechanics, Max Planck Institute for the Science of Light, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. Shovamaye Maharana

    Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
    Competing interests
    The authors declare that no competing interests exist.
  9. Gheorghe Cojoc

    Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
    Competing interests
    The authors declare that no competing interests exist.
  10. Salvatore Girardo

    Biological Optomechanics, Max Planck Institute for the Science of Light, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  11. Andreas Hermann

    Translational Neurodegeneration Section 'Albrecht Kossel', University of Rostock, Rostock, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7364-7791
  12. Simon Alberti

    Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4017-6505
  13. Jochen Guck

    Biological Optomechanics, Max Planck Institute for the Science of Light, Erlangen, Germany
    For correspondence
    jochen.guck@mpl.mpg.de
    Competing interests
    The authors declare that no competing interests exist.

Funding

Deutsche Forschungsgemeinschaft (419138906)

  • Simon Alberti
  • Jochen Guck

Volkswagen Foundation (92847)

  • Simon Alberti
  • Jochen Guck

Alexander von Humboldt-Stiftung

  • Jochen Guck

NOMIS Stiftung

  • Andreas Hermann

Hermann und Lilly Schilling-Stiftung

  • Andreas Hermann

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

Reviewing Editor

  1. Rohit V Pappu, Washington University in St Louis, United States

Publication history

  1. Received: March 17, 2021
  2. Accepted: January 8, 2022
  3. Accepted Manuscript published: January 10, 2022 (version 1)

Copyright

© 2022, Schlüßler 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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