Pocillopora damicornis adult pCO2 x temperature experiment. This project was carried out with collaborator Dr. Hollie Putnam. We have not published the findings yet, but I can tell you this: a 15-day exposure to a pCO2 of 850 ppm did virtually nothing to adult Pocillopora damicornis samples! The question is: does this experiment, all by itself, mean that OA is not a big problem or is it, perhaps, that these corals were from upwelling environments and so already have special adaptations for all manner of environmental change? Or maybe we just didn’t exposed them to high pCO2 for long enough?

For the larval experiment (see  here ).

For the larval experiment (see here).

ATAC=ambient temperature (26C)/ambient  p CO2 (controls), ATHC=ambient temperature/high  p CO2, HTAC=high temperature (29C)/ambient  p CO2, and HTHC=high temperature/high  p CO2. Error bars represent standard error of the mean.

ATAC=ambient temperature (26C)/ambient pCO2 (controls), ATHC=ambient temperature/high pCO2, HTAC=high temperature (29C)/ambient pCO2, and HTHC=high temperature/high pCO2. Error bars represent standard error of the mean.

P. damicornis  nubbins in respiration chambers (by Hollie Putnam).

P. damicornis nubbins in respiration chambers (by Hollie Putnam).

Given my recent loss of faith in transcriptomics, I now propose to use nano-liquid chromatography followed by mass spectrometry (MS) to analyze the proteins after labeling them with  iTRAQ  such that they can be multiplexed (and therefore analyzed in each of only two MS runs). I am currently seeking funds from  National Geographic , the  Fulbright Scholar Program , and the  PADI Foundation  for this work aimed at uncovering the proteomic basis of acclimation to OA in this reef coral.

Given my recent loss of faith in transcriptomics, I now propose to use nano-liquid chromatography followed by mass spectrometry (MS) to analyze the proteins after labeling them with iTRAQ such that they can be multiplexed (and therefore analyzed in each of only two MS runs). I am currently seeking funds from National Geographic, the Fulbright Scholar Program, and the PADI Foundation for this work aimed at uncovering the proteomic basis of acclimation to OA in this reef coral.

Here are some preliminary results from the transcriptome analysis. Of the 36 differentially expressed genes (DEGs), 33, 2, and 1 were from the coral host (94%), either host or  Symbiodinium  (3%), and  Symbiodinium  (3%), respectively. This lack of an mRNA-level response to environmental change in  Symbiodinium  is similar to that documented by other researchers, but contrasts with my long-term temperature  study , in which I found that a higher proportion of DEGs (weighted to account for the fact that  Symbiodinium  comprise only 30-40% of the biomass of  P. damicornis ) were of  Symbiodinium , rather than host coral, origin.

Here are some preliminary results from the transcriptome analysis. Of the 36 differentially expressed genes (DEGs), 33, 2, and 1 were from the coral host (94%), either host or Symbiodinium (3%), and Symbiodinium (3%), respectively. This lack of an mRNA-level response to environmental change in Symbiodinium is similar to that documented by other researchers, but contrasts with my long-term temperature study, in which I found that a higher proportion of DEGs (weighted to account for the fact that Symbiodinium comprise only 30-40% of the biomass of P. damicornis) were of Symbiodinium, rather than host coral, origin.

Heatmap.DEG.jpg