Abstract

Social behaviour is regulated by activity of host-associated microbiota across multiple species. However, the molecular mechanisms mediating this relationship remain elusive. We therefore determined the dynamic, stimulus-dependent transcriptional regulation of germ-free (GF) and GF mice colonised post weaning (exGF) in the amygdala, a brain region critically involved in regulating social interaction. In GF mice the dynamic response seen in controls was attenuated and replaced by a marked increase in expression of splicing factors and alternative exon usage in GF mice upon stimulation, which was even more pronounced in exGF mice. In conclusion, we demonstrate a molecular basis for how the host microbiome is crucial for a normal behavioural response during social interaction. Our data further suggest that social behaviour is correlated with the gene-expression response in the amygdala, established during neurodevelopment as a result of host-microbe interactions. Our findings may help toward understanding neurodevelopmental events leading to social behaviour dysregulation, such as those found in autism spectrum disorders (ASDs).

Data availability

The data discussed in this publication have been deposited in NCBI's Gene Expression Omnibus [86] and are accessible through GEO Series accession number GSE114702 https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE114702

The following data sets were generated

Article and author information

Author details

  1. Roman M Stilling

    APC Microbiome Institute, University College Cork, Cork, Ireland
    For correspondence
    roman.stilling@gmail.com
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7637-5851
  2. Gerard M Moloney

    APC Microbiome Institute, University College Cork, Cork, Ireland
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3672-1390
  3. Feargal J Ryan

    APC Microbiome Institute, University College Cork, Cork, Ireland
    Competing interests
    No competing interests declared.
  4. Alan E Hoban

    APC Microbiome Institute, University College Cork, Cork, Ireland
    Competing interests
    No competing interests declared.
  5. Thomaz Bastiaanssen

    APC Microbiome Institute, University College Cork, Cork, Ireland
    Competing interests
    No competing interests declared.
  6. Fergus Shanahan

    APC Microbiome Institute, University College Cork, Cork, Ireland
    Competing interests
    Fergus Shanahan, principal investigator in the APC Microbiome Institute,University College Cork.
  7. Gerard Clarke

    APC Microbiome Institute, University College Cork, Cork, Ireland
    Competing interests
    Gerard Clarke, faculty member or funded investigator of the APC Microbiome Institute. The APC Microbiome Institute has conducted research funded by Pfizer, GlaxoSmithKline, Proctor & Gamble, Mead Johnson, Suntory Wellness, and Cremo.
  8. Marcus J Claesson

    APC Microbiome Institute, University College Cork, Cork, Ireland
    Competing interests
    Marcus J Claesson, faculty member or funded investigator of the APC Microbiome Institute. The APC Microbiome Institute has conducted research funded by Pfizer, GlaxoSmithKline, Proctor & Gamble, Mead Johnson, Suntory Wellness, and Cremo.
  9. Timothy G Dinan

    APC Microbiome Institute, University College Cork, Cork, Ireland
    Competing interests
    Timothy G Dinan, principal investigator in the APC Microbiome Institute, University College Cork. Has been an invited speaker at meetings organized by Servier, Lundbeck, Janssen, and AstraZeneca..
  10. John F Cryan

    APC Microbiome Institute, University College Cork, Cork, Ireland
    For correspondence
    j.cryan@ucc.ie
    Competing interests
    John F Cryan, principal investigator in the APC Microbiome Institute, University College Cork. Has been an invited speaker at meetings organized by Mead Johnson, Yakult, Alkermes, and Janssen..
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5887-2723

Funding

Science Foundation Ireland (12/RC/2273)

  • Fergus Shanahan
  • Gerard Clarke
  • Marcus J Claesson
  • Timothy G Dinan
  • John F Cryan

Irish Research Council (GOIPD/2014/355)

  • Roman M Stilling
  • John F Cryan

Irish Health Board

  • Timothy G Dinan
  • John F Cryan

NARSAD (20771)

  • Gerard Clarke

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

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations provided by Laboratory Animal Science and Training (LAST) Ireland. All of the animals were handled according to institutional protocols approved by the Animal Ethics Experimentation Committee (AEEC) of University College Cork (#2015/014) and the Health Products Regulatory Authority (HPRA) Ireland (#AE19130/P023). Every effort was made to minimize suffering and animals were killed humanely.

Copyright

© 2018, Stilling 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. Roman M Stilling
  2. Gerard M Moloney
  3. Feargal J Ryan
  4. Alan E Hoban
  5. Thomaz Bastiaanssen
  6. Fergus Shanahan
  7. Gerard Clarke
  8. Marcus J Claesson
  9. Timothy G Dinan
  10. John F Cryan
(2018)
Social interaction-induced activation of RNA splicing in the amygdala of microbiome-deficient mice
eLife 7:e33070.
https://doi.org/10.7554/eLife.33070

Share this article

https://doi.org/10.7554/eLife.33070

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