[Coral-List] Siderastrea siderea transcriptomic response to thermal and pCO2 stress
daviessw at gmail.com
Thu Jul 7 18:10:31 EDT 2016
We would like to draw your attention to our recently published manuscript
in Frontiers in Marine Science titled "Thermal and pCO2 Stress Elicit
Divergent Transcriptomic Responses in a Resilient Coral".
In addition, the *S. siderea* and Clade C *Symbiodinium* transcriptomes are
freely available here:
The oceans are becoming warmer and more acidic as a result of rising
atmospheric pCO2. Transcriptome plasticity may facilitate marine organisms'
acclimation to thermal and acidification stress by tailoring gene
expression to mitigate the impacts of these stressors. Here, we produce the
first transcriptome of the abundant, ubiquitous, and resilient Caribbean
reef-building coral Siderastrea siderea, and investigate this corals'
transcriptomic response to 95 days of thermal (T = 25, 28, 32°C) and
CO2-induced acidification (324, 477, 604, 2553 μatm) stress. The S. siderea
transcriptome was assembled using RNAseq and then Weighted Gene Correlation
Network Analysis was employed to obtain systems-level insights into the
coral's stress response. Exposure of the coral to both elevated temperature
and acidification elicited strong but divergent transcriptomic responses.
Gene Ontology analysis suggests that long-term thermal stress disrupts
homeostasis by increasing transcription of protein-coding genes associated
with protein catabolism and suppressing transcription of genes involved in
responding to environmental stimuli. Both next century (604 μatm) and
extreme-high (2553 μatm) pCO2 stress increased transcription of genes
associated with respiration, highlighting the potentially greater energetic
requirements of maintaining calcification under high-pCO2 conditions. Under
extreme-high-pCO2, increased transcription of H+-transporter genes was
observed, consistent with the proposed role of proton transport in
facilitating coral calcification under elevated pCO2. These results suggest
that 95 days of exposure to 32°C seawater elicits a more adverse
transcriptomic response (i.e., broad scale reductions in gene expression)
than exposure to extreme-high acidification (2553 μatm; i.e., increased
expression of genes associated with ion transport) withinS. siderea—with
the response to extreme warming suggesting cellular shutdown and the
response to extreme acidification indicating capacity for acclimation.
These results are consistent with the observation that rates of net
calcification for the investigated corals were more negatively affected by
the prescribed thermal stress than by the prescribed acidification stress.
This study demonstrates how transcriptome plasticity may promote coral
acclimation to these global change stressors, but that there are limits to
the efficacy of this plasticity.
The paper and additional information can be found here:
Sarah W. Davies M.Sc. Ph.D.
Postdoctoral Research Associate
Department of Marine Sciences
University of North Carolina at Chapel Hill
daviessw at gmail.com
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