Large within, and between, species differences in marine cellular responses: Unpredictability in a changing...

Area of Science:

• Marine biology
• Molecular ecology
• Climate change research

Background:

• Predicting future biodiversity under environmental change necessitates understanding organismal stress responses.
• Current research often focuses on oxygen limitation and heat shock proteins as universal biomarkers, but their consistency across species and stressors is questionable.

Purpose of the Study:

• To investigate the variability of molecular stress responses in Antarctic marine invertebrates exposed to different thermal stresses.
• To determine if common gene expression patterns or heat shock protein responses exist across species and thermal treatments.

Main Methods:

• Exposed three Antarctic marine invertebrate species to four distinct thermal stress treatments (varying ramp rates and acclimation).
• Analyzed gene expression profiles for each species and treatment to identify differentially regulated transcripts.
• Correlated gene expression data across treatments and species to identify shared responses.

Main Results:

• Gene expression profiles were highly individual, varying significantly within and between species, with transcript numbers ranging from 10 to 3011.
• No common molecular response was observed across the four thermal treatments within any single species (0-2 shared transcripts).
• No differentially expressed genes were shared across species, even under identical thermal ramping rates; heat shock protein response was limited and species-specific.

Conclusions:

• Marine invertebrate responses to warming are highly variable at the molecular level.
• Universal biomarkers for marine biodiversity stress are unlikely; species-specific evaluations are crucial.
• Future assessments of climate change impacts on biodiversity must consider local biotic and abiotic factors and target key species.