International Research Team Investigates Marine Species Adaptation

It has long been known that animals can adapt to their environment through changes to their DNA, or their genetic code. More recently, research has shown that non-genetic components may be important, as well — and in some cases essential — for processes such as health, aging and development.

For example, genetically identical twins, despite having identical DNA, are not copies of one another in appearance, behavior, or other characteristics that are dependent on their environmental experiences. Two central non-genetic contributors to individual variation are chemical modifications of the DNA, or epigenetics, and associations with different bacterial species or microbial symbioses.

An international research team led by Adam Reitzel of UNC Charlotte Biological Sciences is investigating how epigenetic regulations and microbial communities influence the adaption of coastal marine species to climate change.

The team received funding in March from the Human Frontier Science Program, as one of only seven teams to receive a Young Investigators’ Grant from 871 teams that sought funding. Reitzel’s collaborators are Sylvain Forêt of the Australian National University and Sebastian Fraune of the Christian-Albrechts University of Kiel, Germany.

“Evidence is growing that climate change has profound effects on marine ecosystems, yet our understanding and ability to predict how species respond in these ecosystems is still very limited,” Reitzel says. Unlike the genes of an animal, epigenetics and microbial composition can rapidly alter due to changes in the environment, making them ideal mechanisms to study how species respond to environmental threats like global warming.

The researchers are modeling their study on the anemone Nematostella vectensis, in which they will first monitor physiological, epigenetic, and microbial changes associated with thermal acclimation. They will then separate the effects of each change through bacterial experimentation, and will carry out gene knockdown and over-expression experiments to determine the function of critical host genes in epigenetic regulations and in the plasticity of the microbiota.

This research will include fieldwork in estuaries throughout the United States, including in North Carolina.

The aim of this research is to determine how epigenetic regulations and microbial communities participate in thermal acclimation of a coastal marine species residing in a dynamic temperature environment, and how these non-genetic factors interact with each other. The researchers hypothesize that changes in the microbial community improve the thermal tolerance of the host, and that the epigenetic landscape is responding both to the shifts in temperature and to the altered microbial composition.

“We believe these results will not only have important consequences for our understanding of the response of marine species to climate change, but will more broadly give us insight into unanswered questions regarding the role of epigenetic regulations and microbes in animal ecology and evolution,” Reitzel says.

The research team also will explore how epigenetics, microbiomes, and genomic mutations intersect, as they are largely studied in isolation at the moment.

The Human Frontier Science Program Organization is a non-profit association based in Strasbourg, France that supports novel, innovative and interdisciplinary basic research focused on the complex mechanisms of living organisms. Research grants are provided for international science teams that wish to combine their expertise to focus on problems in the life sciences. Young Investigators’ Grants are awarded to teams whose members all are within the first five years of obtaining an independent laboratory.

Reitzel has been an assistant professor at UNC Charlotte since 2012 and received his doctoral degree in 2008 from Boston University.

In addition to this funding, he also has received funding from the National Science Foundation for the marine species adaptation research, and is the recipient of a National Institutes of Health AREA grant for his research on circadian clocks. He has been on the review editorial board for Frontiers in Marine Molecular Biology and Ecology since 2013 and has authored more than 60 peer-reviewed journal publications.

Words: Tyler Harris | Image: Vanna Sombatsaphay, used with permission