2020 New Investigator Grant
Katie Barott, Ph.D. Assistant Professor, Department of Biology, University of Pennsylvania
The role of cyclic AMP signaling in acid-base homeostasis of ancestral metazoans
Preventing the loss of coral reefs is one of the great challenges of our lifetimes. These beautiful ecosystems support an incredible amount of biodiversity – including 25% of all marine species – and have enormous economic and cultural importance for communities around the world. The historical success of coral reefs derives from a unique biological innovation: the establishment of symbiosis between corals and single-celled algae that reside within the animal’s cells. These algae harness energy from sunlight via photosynthesis, surrendering the majority of their spoils to their captor and allowing corals to thrive in nutrient-poor tropical waters. Although historically an advantage, this symbiosis has recently transformed into a liability as ocean warming associated with climate change prompts episodic breakdown of the coral-algal partnership, which often leads to coral death. Coupled with ocean warming is the additional stress of ocean acidification, which increases dissolution of coral skeletons and makes their formation more energetically costly for the animal. Furthermore, maintaining acid-base homeostasis is a fundamental necessity for all living organisms, and the mechanisms by which corals maintain homeostasis under normal conditions, let alone as external temperature and pH changes, remain undescribed. In order to address this critical gap in our understanding of coral physiology, this project will investigate the role of an evolutionarily conserved signaling pathway in determining the ability of corals to maintain symbiosis and survive the combinatorial stressors of warming and acidification that are associated with climate change. If we can reveal the fundamental mechanisms that regulate coral biology, then we can better predict if and how corals will survive under the pressure of a changing marine environment. This work will include the development of powerful molecular tools in lab-tractable model species, which will be applied to reef-building corals in natural reef systems in Hawaii. The insights we gain into how corals function on a mechanistic level will improve our ability to predict and perhaps even influence how corals respond to the increasing magnitude of ocean warming and acidification that is happening on coral reefs today. Our research also has implications for human health and the evolution of signaling pathways in animals, as corals are one of the most ancient animal lineages yet have surprisingly high genetic conservation with humans.