Symbiont location, host fitness, and possible coadaptation in a symbiosis between social amoebae and bacteria
- Washington University in St Louis, United States
- Southern Illinois University Edwardsville, United States
Abstract
Recent symbioses, particularly facultative ones, are well suited for unravelling the evolutionary give and take between partners. Here we look at variation in natural isolates of the social amoeba Dictyostelium discoideum and their relationships with bacterial symbionts, Burkholderia hayleyella and Burkholderia agricolaris. Only about a third of field-collected amoebae carry a symbiont. We cured and cross-infected amoebae hosts with different symbiont association histories and then compared host responses to each symbiont type. Before curing, field-collected clones did not vary significantly in overall fitness, but infected hosts produced morphologically different multicellular structures. After curing and reinfecting, host fitness declined. However, natural B. hayleyella hosts suffered fewer fitness costs when reinfected with B. hayleyella, indicating that they have evolved mechanisms to tolerate their symbiont. Our work suggests that amoebae hosts have evolved mechanisms to tolerate specific acquired symbionts; exploring host-symbiont relationships that vary within species may provide further insights into disease dynamics.
Data availability
All raw data has been archived in the Washington University Library: https://doi.org/10.7936/wgnk-2c37
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Raw data from Symbiont location, host fitness, and possible coadaptation in a symbiosis between social amoebae and bacteriaWashington University Open Scholarship, doi.org/10.7936/wgnk-2c37.
Article and author information
Author details
Funding
National Science Foundation (DEB1146375)
- David C Queller
- Joan E Strassmann
The Life Sciences Research Foundation
- Longfei Shu
John Templeton Foundation (43667)
- David C Queller
- Joan E Strassmann
National Science Foundation (IOS1256416)
- David C Queller
National Science Foundation (IOS1656756)
- David C Queller
Simons Foundation
- Longfei Shu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Shu 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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Symbiont location, host fitness, and possible coadaptation in a symbiosis between social amoebae and bacteria
eLife 7:e42660.
https://doi.org/10.7554/eLife.42660
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