Response of holosymbiont pigments from the scleractinian coral Montipora monasteriata to short-term heat stress
Dove, Sophie, Ortiz, Juan Carlos, Enriquez, Susana, Fine, Maoz, Fisher, Paul, Iglesias-Prieto, Roberto, Thornhill, Dan, and Hoegh-Guldberg, Ove (2006) Response of holosymbiont pigments from the scleractinian coral Montipora monasteriata to short-term heat stress. Limnology and Oceanography, 51 (2). pp. 1149-1158.
Heating the scleractinian coral, Montipora monasteriata (Forskăl 1775) to 32°C under <650 mmol quanta m-2 s-1 led to bleaching in the form of a reduction in Peridinin, xanthophyll pool, chlorophyll c2 and chlorophyll a, but areal dinoflagellates densities did not decline. Associated with this bleaching, chlorophyll (Chl) allomerization and dinoflagellate xanthophyll cycling increased. Chl allomerization is believed to result from the interaction of Chl with singlet oxygen (1O2) or other reactive oxygen species. Thermally induced increases in Chl allomerization are consistent with other studies that have demonstrated that thermal stress generates reactive oxygen species in symbiotic dinoflagellates. Xanthophyll cycling requires the establishment of a pH gradient across the thylakoid membrane. Our results indicate that, during the early stages of thermal stress, thylakoid membranes are intact. Different morphs of M. monasteriata responded differently to the heat stress applied: heavily pigmented coral hosts taken from a high-light environment showed significant reductions in green fluorescent protein (GFP)-like homologues, whereas nonhost pigmented high-light morphs experienced a significant reduction in water-soluble protein content. Paradoxically, the more shade acclimated cave morph were, based on Chl fluorescence data, less thermally stressed than either of the high-light morphs. These results support the importance of coral pigments for the regulation of the light environment within the host tissue.
|Item Type:||Article (Refereed Research - C1)|
|Keywords:||pigments, scleractinian corals, Montipora monasteriata, heat stress, bleaching, Peridinin, chlorophyll, dinoflagellates, chlorophyll allomerization|
Reproduced with permission from American Society of Limnology and Oceanography
|Date Deposited:||01 Jun 2007|
|FoR Codes:||06 BIOLOGICAL SCIENCES > 0602 Ecology > 060205 Marine and Estuarine Ecology (incl Marine Ichthyology) @ 0%
06 BIOLOGICAL SCIENCES > 0605 Microbiology > 060504 Microbial Ecology @ 0%
|Citation Count from Web of Science||
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