Investigating the transcriptomic patterns of the Antarctic pteropod Limacina helicina antarctica, and how it will be affected by ocean warming and ocean acidification
Pteropods are a major food source for many Antarctic fish species, thereby playing an integral role in the Antarctic food web. Unfortunately high latitude seas are predicted to experience ocean acidification at an accelerated rate due to the high solubility of carbon dioxide in cold waters. Furthermore, organisms that inhabit the Southern Ocean may be particularly limited in their ability to adapt or migrate. Thus, negative impacts of climate change on the Antarctic pteropod Limacina helicina antarctica could disrupt the vast diversity of Antarctic marine fauna that it supports.
In collaboration with other members of the Hofmann Lab, we investigated how the metabolism of these pteropods were altered in response to changes in pH and temperature. Additionally, we explored the gene expression patterns of L. helicina antarctica collected in the field, using transcriptomic data in combination with oceanographic data to gain insight into how pteropod populations are responding to current ocean conditions.
We found that pH and temperature interacted additively to affect metabolic rates. Metabolic rates increased in juvenile pteropods exposed to simultaneous stressors of low pH and high temperature.
In another study, we analyzed seasonal transcriptomic data that suggested that after over-wintering, the pteropods progress towards full maturity in the early summer when food becomes more available.
Kevin M. Johnson, Juliet M. Wong, Umihiko Hoshijima, Cailan S. Sugano, and Gretchen E. Hofmann (2019). Seasonal transcriptomes of the Antarctic pteropod, Limacina helicina antarctica. Marine Environmental Research 143: 49-59. https://doi.org/10.1016/j.marenvres.2018.10.006.
Umihiko Hoshijima, Juliet M. Wong, and Gretchen E. Hofmann (2017). Additive effects of pCO2 and temperature on respiration rates of the Antarctic pteropod, Limacina helicina antarctica. Conservation Physiology 5(1): cox064. https://doi.org/10.1093/conphys/cox064.