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To understand species response and vulnerability to ocean warming, the underlying biological mechanisms can be examined through the emerging field of ecological proteomics. Proteomics is a powerful tool in identifying and quantifying important proteins. While octopuses are renowned for their intelligence and adaptability, it is still unclear whether they will thrive in future oceans under the current climate crisis. The hypothesis tested in this study is that exposure of Octopus berrima embryos to projected thermal conditions will be reflected in proteome changes that provide insight into mechanisms of temperature adaptation during ocean warming. Results from this study represent the first proteomic analysis of octopuses under ocean warming, thereby informing us of potential biomarkers and performance of octopuses under thermal stress.
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Projected ocean temperatures impair key proteins used in vision of octopus hatchlings
Abstract Global warming is one of the most significant and widespread effects of climate change. While early life stages are particularly vulnerable to increasing temperatures, little is known about the molecular processes that underpin their capacity to adapt to temperature change during early development. Using a quantitative proteomics approach, we investigated the effects of thermal stress on octopus embryos. We exposedOctopus berrimaembryos to different temperature treatments (control 19°C, current summer temperature 22°C, or future projected summer temperature 25°C) until hatching. By comparing their protein expression levels, we found that future projected temperatures significantly reduced levels of key eye proteins such as S‐crystallin and retinol dehydrogenase 12, suggesting the embryonic octopuses had impaired vision at elevated temperature. We also found that this was coupled with a cellular stress response that included a significant elevation of proteins involved in molecular chaperoning and redox regulation. Energy resources were also redirected away from non‐essential processes such as growth and digestion. These findings, taken together with the high embryonic mortality observed under the highest temperature, identify critical physiological functions of embryonic octopuses that may be impaired under future warming conditions. Our findings demonstrate the severity of the thermal impacts on the early life stages of octopuses as demonstrated by quantitative proteome changes that affect vision, protein chaperoning, redox regulation and energy metabolism as critical physiological functions that underlie the responses to thermal stress.
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- Award ID(s):
- 2127516
- PAR ID:
- 10498974
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Global Change Biology
- Volume:
- 30
- Issue:
- 4
- ISSN:
- 1354-1013
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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