Tropical coral reefs are among the most diverse and productive ecosystems in the world and support a range of ecosystem goods and services that contribute to the well-being of millions of people. However, coral reef cover is declining globally because of local and global anthropogenic impacts. In particular, the frequency and severity of mass bleaching events caused by global climate change are expected to further increase in the future and threaten the long-term survival of coral reefs.
The trophic and structural foundations of this marine ecosystem rely on the mutualistic relationships existing between scleractinians and their associated microbial symbionts (photosynthetic dinoflagellates, bacteria, archaea etc.), forming a meta-organism called the coral holobiont. Despite an increasing understanding about the molecular underpinnings of coral holobiont function, there are still significant gaps in our knowledge. Uncovering the underlying fundamental processes involved in the establishment and maintenance of the interaction between the coral host and its microbial symbionts is essential if we are to fully understand the mechanisms by which they are impacted by stress and whether or how corals might adapt to environmental perturbations and survive.
The use of model organisms has a successful track record, leading to significant progress in molecular, cellular, and developmental biology. The model system Aiptasia, i.e. Exaiptasia diaphana, is a small sea anemone found globally in temperate and tropical marine waters, and intracellularly hosts symbiotic dinoflagellates (family: Symbiodiniaceae). Unlike corals, Aiptasia lacks a calcium carbonate skeleton, can be easily manipulated and cultivated under laboratory conditions, and lives in a facultative symbiotic state, which allows conducting experiments on aposymbiotic control animals. Since its formal proposal as a model system to study cnidarian symbiosis in 2008, Aiptasia has been adopted by a growing number of research groups and has enabled the development of tools to explore research questions on: development and cellular regeneration; the onset, maintenance, and disruption of symbiosis; and metabolic interactions, among others.
The last decade has seen the development of tools allowing the adoption of Aiptasia by a growing number of laboratories. The community made available a genome and developed omics tools, but to make this sea anemone a key model system in coral reef research and the symbiosis field, the Aiptasia community still needs to overcome a few hurdles like closing the life cycle, and developing gene-editing tools and new imaging techniques, etc.
For this Research Topic, we seek to solicit contributions that showcase the state-of-the-art of the Aiptasia model system and studies that show how it can contribute to coral reef conservation. Through this article collection, we also would like to provide inspiration and guidance to the next generation of biologists interested in symbiotic interactions.
We encourage the submission of the following article types: Brief Research Report, Original Research, Methods, (Mini) Review, Opinion, and Perspective. All topics are welcome, but we are especially interested in articles that employ Aiptasia to elucidate the following aspects of the cnidarian-dinoflagellate symbiosis and coral reef biology more generally:
Aiptasia Symbiosis Resource: https://aiptasia-resource.org/Image Copyright: Nils Radecker
- Developmental research
- Cell biology of symbiosis, including symbiosis onset, establishment and maintenance
- Genomic, transcriptomic, proteomic or metabolomic approaches for understanding symbiosis function
- Microbiome studies (manipulation, probiotics, etc.)
- Bleaching physiology and adaptability to climate change
- Tools development, including (but not limited to) those for enhancing resilience to climate change
- Research comparing or merging the observations in Aiptasia with those from other model systems and/or corals