A5087960805- Photosynthetic Processes and Mechanisms
- Coral and Marine Ecosystems Studies
- Photoreceptor and optogenetics research
- Marine and coastal plant biology
- Light effects on plants
- Coastal wetland ecosystem dynamics
- Plant Stress Responses and Tolerance
- Mitochondrial Function and Pathology
- Plant responses to elevated CO2
- Marine Biology and Ecology Research
- Spectroscopy and Quantum Chemical Studies
- Marine and fisheries research
- Marine and coastal ecosystems
- Ocean Acidification Effects and Responses
- Marine Sponges and Natural Products
- Plant and animal studies
- Plant Water Relations and Carbon Dynamics
- Cassava research and cyanide
- ATP Synthase and ATPases Research
- Vitamin C and Antioxidants Research
- Algal biology and biofuel production
- Electrocatalysts for Energy Conversion
- Polar Research and Ecology
- Pharmaceutical Economics and Policy
- Advanced Combustion Engine Technologies
University of the Ryukyus
1998-2023
National Institute for Basic Biology
2003-2021
The Graduate University for Advanced Studies, SOKENDAI
2016-2020
Australian National University
2009-2019
Bayer (Japan)
2018-2019
Australian Research Council
2007-2012
Okayama University
2012
ARC Centre of Excellence in Plant Energy Biology
2009-2011
Tohoku University
2010
Institut des Sciences des Plantes de Montpellier
2009
Under strong light, photosystem II (PSII) of oxygenic photosynthetic organisms is inactivated, and this phenomenon called photoinhibition. In a widely accepted model, photoinhibition induced by excess light energy, which absorbed chlorophyll but not utilized in photosynthesis. Using monochromatic from the Okazaki Large Spectrograph thylakoid membranes Thermosynechococcus elongatus, we observed that UV blue inactivated oxygen-evolving complex much faster than photochemical reaction center...
In a coral-algae symbiotic system, heat-dependent photoinhibition of photosystem II (PSII) leads to coral bleaching. When the reef-building Acropora digitifera was exposed light, moderate increase temperature induced bleaching through photobleaching algal pigments, but not expulsion algae. Monitoring PSII revealed that ascribed inhibition repair photodamaged PSII, and heat susceptibility machinery varied among species. We conclude efficiency photosynthesis determines species under elevated...
Abstract Cyclic electron flow (CEF) around photosystem I has a role in avoiding photoinhibition of II (PSII), which occurs under conditions the rate photodamage to PSII exceeds its repair. However, molecular mechanism underlying how CEF contributes photoprotection is not yet well understood. We examined effect impairment and thermal energy dissipation (qE) on using (pgr5) qE (npq1 npq4) mutants Arabidopsis (Arabidopsis thaliana) exposed strong light. Impairment by mutation pgr5 suppressed...
Abstract Oxygenation of ribulose-1,5-bisphosphate catalyzed by Rubisco produces glycolate-2-P. The photorespiratory pathway, which consists carbon and nitrogen cycles, metabolizes glycolate-2-P to the Calvin cycle intermediate glycerate-3-P is proposed be important for avoiding photoinhibition photosystem II (PSII), especially in C3 plants. We show here that mutants Arabidopsis (Arabidopsis thaliana) with impairment ferredoxin-dependent glutamate synthase, serine hydroxymethyltransferase,...
In C(3) plants, CO(2) assimilation is limited by ribulose 1,5-bisphosphate (RuBP) regeneration rate at high CO(2). RuBP in turn determined either the chloroplast electron transport capacity to generate NADPH and ATP or activity of Calvin cycle enzymes involved RuBP. Here, transgenic tobacco (Nicotiana tabacum 'W38') expressing an antisense gene directed transcript Rieske iron-sulfur protein cytochrome (Cyt) b(6)/f complex δ-subunit synthase have been used investigate effect a reduction these...
The production of oxygen and the supply energy for life on earth rely process photosynthesis using sunlight. Paradoxically, sunlight damages photosynthetic machinery, primarily photosystem II (PSII), leading to photoinhibition loss plant performance. However, there is uncertainty about which wavelengths are most damaging PSII under In this work we examined in a simple experiment where Arabidopsis (Arabidopsis thaliana) leaves were exposed different by dispersing solar radiation across...
Coral bleaching, caused by heat stress, is accompanied the light-induced loss of photosynthetic pigments in situ symbiotic dinoflagellate algae (Symbiodinium spp.). However, molecular mechanisms responsible for pigment are poorly understood. Here, we show that moderate stress causes photobleaching through inhibition de novo synthesis intrinsic light-harvesting antennae [chlorophyll a-chlorophyll c(2)-peridinin-protein complexes (acpPC)] cultured Symbiodinium and two Clade A species showing...
Coral bleaching caused by heat stress is accompanied photoinhibition, which occurs under conditions where the rate of photodamage to photosystem II (PSII) exceeds its repair, in symbiotic algae (Symbiodinium spp.) within corals. However, mechanism stress-induced photoinhibition Symbiodinium still remains poorly understood. In present work, we have investigated effect elevated temperature on processes associated with repair photodamaged PSII cultured (OTcH-1 and CS-73). Severe was observed at...
Abstract Light damages photosynthetic machinery, primarily photosystem II (PSII) and it results in photoinhibition. A new photodamage model, the two-step suggests that to PSII initially occurs at oxygen evolving complex (OEC) by light energy absorbed manganese reaction center is subsequently damaged pigments due limitation of electrons center. However, still uncertain whether this model applicable under visible as absorbs only weakly. In present study, we identified initial site upon...
Abstract The photosynthetic machinery and, in particular, the photosystem II (PSII) complex are susceptible to strong light, and effects of light referred as photodamage or photoinhibition. In living organisms, photodamaged PSII is rapidly repaired a result, extent photoinhibition represents balance between rates repair PSII. this study, we examined roles electron transport ATP synthesis these two processes by monitoring them separately systematically cyanobacterium Synechocystis sp. PCC...
Nitric oxide (NO) is a bioactive molecule involved in diverse physiological functions plants. Here we demonstrate that NO capable of regulating the activity photophosphorylation chloroplasts. The electron transport photosystem II determined from chlorophyll fluorescence was inhibited by NO. also light‐induced ΔpH formation across thylakoid membrane. High concentrations nitrite and nitrate did not show such inhibitory effects, suggesting inhibition due to uncoupling effects oxidized products...
Human-induced environmental changes have been linked directly with loss of biodiversity. Coral reefs, which severely impacted by anthropogenic activities over the last few decades, exemplify this global problem and provide an opportunity to develop research addressing key knowledge gaps through 'omics'-based approaches. While many stressors, e.g. warming, ocean acidification, overfishing coastal development identified, there is urgent need understand how corals function at a basic level in...
Oxygen plays an important role in photosynthesis by participating a number of O2-consuming reactions. O2 inhibits CO2 fixation stimulating photorespiration, thus reducing plant production. interacts with photosynthetic electron transport the chloroplasts' thylakoids two main ways: accepting electrons from PSI (Mehler reaction); and reduced plastoquinone (PQ) mediated plastid terminal oxidase (PTOX). In this study, we show, using 101 species, that there is difference potential for flow to...
Significance Reef-building corals cannot survive without symbiotic algae, Symbiodinium , on which they depend for most of their energy. Most coral species gain symbionts from the environment early in life, and possibly after bleaching (i.e., loss response to stress). However, density reefs is very low. Although it has long been hypothesized that must be able attract free-living such a mechanism yet identified. Here, we use series experiments demonstrate using endogenous GFP-related green...
Synchronized mass coral spawning typically occurs several days after a full moon once year. It is expected that day determined by corals sensing environmental change regulated the lunar cycle (i.e., tide or moonlight); however, exact regulatory mechanism remains unknown. Here, we demonstrate how moonlight influences process of coral, Dipsastraea speciosa When in field were shaded 1 and 3 d before moon, always occurred 5 shading commenced. These results suggest suppresses spawning: hypothesis...
Abstract Reef-building corals form symbiotic relationships with dinoflagellates of the genus Symbiodinium. Symbiodinium are genetically and physiologically diverse, may be able to adapt different environments by altering their dominant phylotype. Notably, each coral species associates only specific phylotypes, consequently diversity symbionts available host is limited specificity. Currently, it widely presumed that specificity determined combination cell-surface molecules on symbiont. Here...