| Dynamic Regulation of Photoprotection Determines Thermal Tolerance of two Phylotypes of Symbiodinium Clade A at two Photon Fluence Rates. | |
| | |
MedLine Citation:
|
PMID: 22117932 Owner: NLM Status: Publisher |
Abstract/OtherAbstract:
|
Coral bleaching is the manifestation of the dysfunction of the symbiosis between scleractinian corals and dinoflagellates of the diverse genus Symbiodinium and is induced by elevated temperatures and high irradiance. We investigated the photophysiological response of two genetically distinct Symbiodinium subtypes within clade A upon exposure to elevated temperatures at two light intensities for three weeks. While both subtypes displayed a characteristic photoacclimation to high light (decrease in light-harvesting pigments, lower photochemical efficiency of PSII, increased xanthophyll pool sizes), the tolerance towards thermal stress clearly differed between the two subtypes. Symbiodinium Ax was highly susceptible to chronic photoinhibition at temperatures ≥ 30 °C, which was exacerbated under high light conditions. A1 showed a capacity for photoacclimation and high thermal tolerance, which might be related to higher cellular concentrations of photoprotective xanthophylls and the low-molecular antioxidant glutathione (GSx) along with the dynamic regulation of these photoprotective pathways. Whereas high light conditions induced both accumulation of diatoxanthin and GSx, thermal stress further stimulated xanthophyll cycling, which might compensate for diminished amounts of GSx at elevated temperatures. Our results show that the two clade A subtypes clearly differ in their strategies to cope with thermal stress in combination with high irradiance. |
| | |
Authors:
|
Wiebke E Krämer; Isabel Caamaño-Ricken; Claudio Richter; Kai Bischof |
Publication Detail:
|
Type: JOURNAL ARTICLE Date: 2011-11-24 |
Journal Detail:
|
Title: Photochemistry and photobiology Volume: - ISSN: 1751-1097 ISO Abbreviation: - Publication Date: 2011 Nov |
Date Detail:
|
Created Date: 2011-11-28 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 0376425 Medline TA: Photochem Photobiol Country: - |
Other Details:
|
Languages: ENG Pagination: - Citation Subset: - |
Copyright Information:
|
Photochemistry and Photobiology © 2011 American Society for Photobiology. |
Affiliation:
|
Department of Marine Botany, University of Bremen, Leobener Straße NW2, 28359 Bremen, Germany Alfred Wegener Institute for Polar and Marine Research, Columbusstraße, 27568 Bremerhaven, Germany. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Vitamin D status of pregnant and non-pregnant women of reproductive age living in Hanoi City and the...
Next Document: Herbal medicine use among urban residents in Lagos, Nigeria.