How does rising atmospheric CO2 affect marine organisms?

Click to locate material archived on our website by topic

How Coral Polyps May Counteract Ocean Water Acidification

Paper Reviewed
Ohno, Y., Iguchi, A., Shinzato, C., Inoue, M., Suzuki, A., Sakai, K. and Nakamura, T. 2017. An aposymbiotic primary coral polyp counteracts acidification by active pH regulation. Scientific Reports 7: 40342, DOI: 10.1038/srep40324.

Noting that "corals build their skeletons using extracellular calcifying fluid located in the tissue-skeleton interface," Ohno et al. (2017) describe how they "performed direct pH imaging at calcification sites (subcalicoblastic medium, SCM) to visualize active pH upregulation in live aposymbiotic primary coral polyps treated with HCL-acidified seawater." And what did they learn by so doing?

The seven scientists say they observed (1) "acid-induced oscillations in the pH of SCM (pHSCM) in 24% of polyps examined," and that (2) "corals can regulate pHSCM more dynamically than was previously believed," while further noting that (3) "these observations will have important implications for determining how corals regulate pHSCM during calcification." And they propose, therefore, that (4) "corals can sense ambient seawater pH via their innate pH-sensitive systems and, therefore that they can (5) "regulate pHSCM using several unknown pH-regulating ion transporters that coordinate with multicellular signaling occurring in coral tissue."

Posted 27 April 2017