Repair machinery of symbiotic photosynthesis as the primary target of heat stress for reef-building corals.
In a coral-algae symbiotic system, heat-dependent photoinhibition of photosystem II (PSII) leads to coral bleaching. When the reef-building coral Acropora digitifera was exposed to light, a moderate increase of temperature induced coral bleaching through photobleaching of algal pigments, but not through expulsion of symbiotic algae. Monitoring of PSII photoinhibition revealed that heat-dependent photoinhibition was ascribed to inhibition of the repair of photodamaged PSII, and heat susceptibility of the repair machinery varied among coral species. We conclude that the efficiency of the photosynthesis repair machinery determines the bleaching susceptibility of coral species under elevated seawater temperatures.
Faculty of Science, University of the Ryukyus, Okinawa, 903-0213 Japan.
Shunichi
S
Takahashi
Takashi
T
Nakamura
Manabu
M
Sakamizu
Robert
R
van Woesik
Hideo
H
Yamasaki
D000818:Animals; D037421:Anthozoa / Q000166:cytology / Q000378:metabolism* / Q000528:radiation effects; D056890:Eukaryota / Q000166:cytology / Q000378:metabolism* / Q000528:radiation effects; D010775:Photic Stimulation; D038761:Photobleaching / Q000528:radiation effects*; D010788:Photosynthesis / Q000502:physiology* / Q000528:radiation effects; D045332:Photosystem II Protein Complex / Q000378:metabolism / Q000528:radiation effects; D012038:Regeneration / Q000502:physiology / Q000528:radiation effects; D013312:Stress, Physiological / Q000378:metabolism*; D013559:Symbiosis / Q000502:physiology* / Q000528:radiation effects; D013696:Temperature
D045332:Photosystem II Protein Complex