Abstract

In biological systems, liquid and solid-like biomolecular condensates may contain the same molecules but their behaviour, including movement, elasticity and viscosity, is different on account of distinct physicochemical properties. As such, it is known that phase transitions affect the function of biological condensates and that material properties can be tuned by several factors including temperature, concentration and valency. It is, however, unclear if some factors are more efficient than others at regulating their behaviour. Viral infections are good systems to address this question as they form condensates de novo as part of their replication programmes. Here, we used influenza A virus liquid cytosolic condensates, A.K.A viral inclusions, to provide a proof of concept that liquid condensate hardening via changes in the valency of its components is more efficient than altering their concentration or the temperature of the cell. Liquid IAV inclusions may be hardened by targeting vRNP interactions via the known NP oligomerizing molecule, nucleozin, both in vitro and in vivo without affecting host proteome abundance nor solubility. This study is a starting point for understanding how to pharmacologically modulate the material properties of IAV inclusions and may offer opportunities for alternative antiviral strategies.

Data availability

The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE (PubMed ID: 34723319) partner repository with the dataset identifier PXD034778.oReviewer account details:oUsername: reviewer_pxd034778@ebi.ac.ukoPassword: BprURfLwAll computer code or algorithm used to generate the results reported in the paper are available at 10.5281/zenodo.7709159.All data for figures Figure 1-8 and Figure S1-2 are provided with this paper in 10.5281/zenodo.7709159. Sequences of described viruses are accessible from the NCBI virus under accession number GCF_000865725.1.

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Temitope Akhigbe Etibor

    Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
    Competing interests
    The authors declare that no competing interests exist.
  2. Silvia Vale-Costa

    Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
    Competing interests
    The authors declare that no competing interests exist.
  3. Sindhuja Sridharan

    European Molecular Biology Laboratory, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Daniela Brás

    Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
    Competing interests
    The authors declare that no competing interests exist.
  5. Isabelle Becher

    European Molecular Biology Laboratory, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7170-2235
  6. Victor Hugo Mello

    Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
    Competing interests
    The authors declare that no competing interests exist.
  7. Filipe Ferreira

    Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
    Competing interests
    The authors declare that no competing interests exist.
  8. Marta Alenquer

    Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
    Competing interests
    The authors declare that no competing interests exist.
  9. Mikhail M Savitski

    European Molecular Biology Laboratory, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2011-9247
  10. Maria-João Amorim

    Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
    For correspondence
    mjamorim@igc.gulbenkian.pt
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4129-6659

Funding

European Research Council (101001521)

  • Maria-João Amorim

Fundação para a Ciência e a Tecnologia (PD/BD/128436/2017,PD/BD/148391/2019 and UI/BD/152254/2021)

  • Temitope Akhigbe Etibor
  • Daniela Brás
  • Victor Hugo Mello

European Commission Twinning Action Symbnet (952537)

  • Maria-João Amorim

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

Reviewing Editor

  1. Mauricio Comas-Garcia, Universidad Autónoma de San Luis Potosí, Mexico

Ethics

Animal experimentation: Animals were group housed in individually ventilated cages with access to food and water ad libitum. This research project was ethically reviewed and approved by both the Ethics Committee and the Animal Welfare Body of the IGC (license reference: A003.2021), and by the Portuguese National Entity that regulates the use of laboratory animals (DGAV - Direção Geral de Alimentação e Veterinária (license references: 0421/000/000/2022, Controlling influenza A virus liquid organelles - LOFLU, funded by the European Research Council). All experiments conducted on animals followed the Portuguese (Decreto-Lei nº 113/2013) and European (Directive 2010/63/EU) legislations, concerning housing, husbandry, and animal welfare.

Version history

  1. Preprint posted: August 5, 2022 (view preprint)
  2. Received: November 25, 2022
  3. Accepted: March 16, 2023
  4. Accepted Manuscript published: April 4, 2023 (version 1)
  5. Version of Record published: May 2, 2023 (version 2)

Copyright

© 2023, Etibor 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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  1. Temitope Akhigbe Etibor
  2. Silvia Vale-Costa
  3. Sindhuja Sridharan
  4. Daniela Brás
  5. Isabelle Becher
  6. Victor Hugo Mello
  7. Filipe Ferreira
  8. Marta Alenquer
  9. Mikhail M Savitski
  10. Maria-João Amorim
(2023)
Defining basic rules for hardening influenza A virus liquid condensates
eLife 12:e85182.
https://doi.org/10.7554/eLife.85182

Share this article

https://doi.org/10.7554/eLife.85182

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