For more than 30 years, the association between the Hawaiian bobtail squid, Euprymna scolopes, and the bioluminescent bacterium Vibrio fischeri has been studied as a model system for understanding the colonization of animal epithelia by symbiotic bacteria. The squid–vibrio light-organ system provides the exquisite resolution only possible with the study of a binary partnership. The impact of this relationship on the partners’ biology has been broadly characterized, including their ecology and evolutionary biology as well as the underlying molecular mechanisms of symbiotic dynamics. Much has been learned about the factors that foster initial light-organ colonization, and more recently about the maturation and long-term maintenance of the association. This Review synthesizes the results of recent research on the light-organ association and also describes the development of new horizons for E. scolopes as a model organism that promises to inform biology and biomedicine about the basic nature of host–microorganism interactions.
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The authors thank E. Ruby, K. Visick and E. Stabb for helpful comments about the manuscript. Work in the authors’ laboratories has been supported by the National Science Foundation NSF IOS 1557914 to S.V.N.; National Institutes of Health (NIH), National Institute of Allergy and Infectious Diseases R37 AI50661 to M.J.M.-N.; NIH, Office of the Director, R01 OD11024 and GM135254 (M.J.M.-N.); and National Science Foundation, Integrated NSF Support Promoting Interdisciplinary Research and Education INSPIRE Grant MCB1608744 (to M.J.M.-N.).
The authors declare no competing interests.
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The fitness of both symbiotic partners is enhanced by the association.
(Or pathogenesis). The fitness of one partner is enhanced and the other is diminished.
The fitness of one symbiotic partner is enhanced and the other is unaffected.
Often refers to the group of microorganisms found in a specific habitat, such as a host or biofilm.
Often used interchangeably with the term microbiota. However, some researchers use microbiome to refer to the collective genomes of the microbiota.
Multiple analysis approaches applied to a biological system, for example, genomics, transcriptomics, proteomics and metabolomics.
Also known as metaorganism. Refers to a host and all of its associated partners.
Collective metabolites associated with a given organism or organisms.
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Nyholm, S.V., McFall-Ngai, M.J. A lasting symbiosis: how the Hawaiian bobtail squid finds and keeps its bioluminescent bacterial partner. Nat Rev Microbiol (2021). https://doi.org/10.1038/s41579-021-00567-y
Nature Reviews Microbiology (2021)
Nature Reviews Microbiology (2021)