Electrophysiological evidence for light-activated cation transport in calcifying corals.

Taubner, Isabelle, Hu, Marian Yong-An , Eisenhauer, Anton and Bleich, Markus (2019) Electrophysiological evidence for light-activated cation transport in calcifying corals. Proceedings of the Royal Society B: Biological Sciences, 286 (20182444). DOI 10.1098/rspb.2018.2444.

[img] Text
Taubner.pdf - Published Version
Restricted to Registered users only

Download (1198Kb) | Contact
[img] Text
Taubner_Suppl.docx - Supplemental Material
Restricted to Registered users only

Download (228Kb) | Contact

Supplementary data:

Abstract

Light has been demonstrated to enhance calcification rates in hermatypic coral species. To date, it remains unresolved whether calcifying epithelia change their ion transport activity during illumination, and whether such a process is mediated by the endosymbiotic algae or can be controlled by the coral host itself. Using a modified Ussing chamber in combination with H+ sensitive microelectrode measurements, the present work demonstrates that light triggers the generation of a skeleton positive potential of up to 0.9 mV in the hermatypic coral Stylophora pistillata. This potential is generated by a net flux of cations towards the skeleton and reaches its maximum at blue (450 nm) light. The effects of pharmacological inhibitors targeting photosynthesis 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) and anion transport 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) were investigated by pH microelectrode measurements in coral tissues demonstrating a rapid decrease in tissue pH under illumination. However, these inhibitors showed no effect on the electrophysiological light response of the coral host. By contrast, metabolic inhibition by cyanide and deoxyglucose reversibly inhibited the light-induced cation flux towards the skeleton. These results suggest that ion transport across coral epithelia is directly triggered by blue light, independent of photosynthetic activity of algal endosymbionts. Measurements of this very specific and quantifiable physiological response can provide parameters to identify photoreception mechanisms and will help to broaden our understanding of the mechanistic link between light stimulation and epithelial ion transport, potentially relevant for calcification in hermatypic corals.

Document Type: Article
Keywords: ion transport, Ussing chamber, microsensor, light spectrum photosynthesis, Stylophora pistillata
Research affiliation: Kiel University
OceanRep > GEOMAR > FB2 Marine Biogeochemistry > FB2-MG Marine Geosystems
Kiel University > Kiel Marine Science
OceanRep > The Future Ocean - Cluster of Excellence
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1098/rspb.2018.2444
ISSN: 0962-8452
Related URLs:
Projects: BIOACID, TRION II, Emmy Noether Program
Date Deposited: 20 Feb 2019 08:21
Last Modified: 23 Sep 2019 19:26
URI: http://oceanrep.geomar.de/id/eprint/45845

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...