Spontaneous body wall contractions stabilize the fluid microenvironment that shapes host-microbe associations
Abstract
The freshwater polyp Hydra is a popular biological model system; however, we still do not understand one of its most salient behaviours, the generation of spontaneous body wall contractions. Here, by applying experimental fluid dynamics analysis and mathematical modelling, we provide functional evidence that spontaneous contractions of body walls enhance the transport of chemical compounds from and to the tissue surface where symbiotic bacteria reside. Experimentally, a reduction in the frequency of spontaneous body wall contractions is associated with a changed composition of the colonizing microbiota. Together, our findings suggest that spontaneous body wall contractions create an important fluid transport mechanism that (1) may shape and stabilize specific host-microbe associations and (2) create fluid microhabitats that may modulate the spatial distribution of the colonizing microbes. This mechanism may be more broadly applicable to animal-microbe interactions since research has shown that rhythmic spontaneous contractions in the gastrointestinal tracts are essential for maintaining normal microbiota.
Data availability
All data presented in the main manuscript and supplemental figures is publicly available at NCBI Bioproject PRJNA842888The 16S rRNA sequencing raw data are deposited at the SRA and are available under the project ID PRJNA842888.
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Funding
Deutsche Forschungsgemeinschaft (CRC 1182 Origin and Function of Metaorganisms"")
- Janna C Nawroth
- Christoph Giez
- Alexander Klimovich
- Eva Kanso
- Thomas CG Bosch
Deutsche Forschungsgemeinschaft (CRC 1461 Neurotronics: Bio-Inspired Information Pathways"")
- Thomas CG Bosch
Deutsche Forschungsgemeinschaft (CRC 1461 Neurotronics: Bio-Inspired Information Pathways"")
- Alexander Klimovich
National Institutes of Health (grant 1 R01 HL 15362201-A)
- Janna C Nawroth
- Christoph Giez
- Alexander Klimovich
- Eva Kanso
National Science Foundation (INSPIRE grant 1608744)
- Janna C Nawroth
- Christoph Giez
- Alexander Klimovich
- Eva Kanso
National Science Foundation (RAISE grant)
- Eva Kanso
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Nawroth 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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