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Measuring Photonics in Photosynthesis: Combined Micro-Fourier Image Spectroscopy and Pulse Amplitude Modulated Chlorophyll Fluorimetry at the Micrometre-Scale. Biomimetics (Basel) 2022; 7:biomimetics7030107. [PMID: 35997427 PMCID: PMC9397104 DOI: 10.3390/biomimetics7030107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/27/2022] [Accepted: 08/01/2022] [Indexed: 11/17/2022] Open
Abstract
Natural photonic structures are common across the biological kingdoms, serving a diversity of functionalities. The study of implications of photonic structures in plants and other phototrophic organisms is still hampered by missing methodologies for determining in situ photonic properties, particularly in the context of constantly adapting photosynthetic systems controlled by acclimation mechanisms on the cellular scale. We describe an innovative approach to determining spatial and spectral photonic properties and photosynthesis activity, employing micro-Fourier Image Spectroscopy and Pulse Amplitude Modulated Chlorophyll Fluorimetry in a combined microscope setup. Using two examples from the photosynthetic realm, the dynamic Bragg-stack-like thylakoid structures of Begonia sp. and complex 2.5 D photonic crystal slabs from the diatom Coscinodiscus granii, we demonstrate how the setup can be used for measuring self-adapting photonic-photosynthetic systems and photonic properties on single-cell scales. We suggest that the setup is well-suited for the determination of photonic–photosynthetic systems in a diversity of organisms, facilitating the cellular, temporal, spectral and angular resolution of both light distribution and combined chlorophyll fluorescence determination. As the catalogue of photonic structure from photosynthetic organisms is rich and diverse in examples, a deepened study could inspire the design of novel optical- and light-harvesting technologies.
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Krujatz F, Dani S, Windisch J, Emmermacher J, Hahn F, Mosshammer M, Murthy S, Steingroewer J, Walther T, Kühl M, Gelinsky M, Lode A. Think outside the box: 3D bioprinting concepts for biotechnological applications – recent developments and future perspectives. Biotechnol Adv 2022; 58:107930. [DOI: 10.1016/j.biotechadv.2022.107930] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 02/17/2022] [Indexed: 12/14/2022]
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Kramer N, Tamir R, Ben‐Zvi O, Jacques SL, Loya Y, Wangpraseurt D. Efficient light‐harvesting of mesophotic corals is facilitated by coral optical traits. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13948] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Raz Tamir
- School of Zoology Tel‐Aviv University Tel Aviv Israel
- The Interuniversity Institute for Marine Sciences of Eilat Eilat Israel
| | - Or Ben‐Zvi
- School of Zoology Tel‐Aviv University Tel Aviv Israel
- The Interuniversity Institute for Marine Sciences of Eilat Eilat Israel
| | - Steven L. Jacques
- Department of Bioengineering University of Washington Seattle WA USA
| | - Yossi Loya
- School of Zoology Tel‐Aviv University Tel Aviv Israel
| | - Daniel Wangpraseurt
- Department of Nanoengineering University of California San Diego San Diego CA USA
- Department of Chemistry University of Cambridge Cambridge UK
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Soto D, De Palmas S, Ho M, Denis V, Allen Chen C. A molecular census of early-life stage scleractinian corals in shallow and mesophotic zones. Ecol Evol 2021; 11:14573-14584. [PMID: 34765126 PMCID: PMC8571570 DOI: 10.1002/ece3.8122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/27/2021] [Accepted: 07/29/2021] [Indexed: 11/06/2022] Open
Abstract
The decline of coral reefs has fueled interest in determining whether mesophotic reefs can shield against disturbances and help replenish deteriorated shallower reefs. In this study, we characterized spatial (horizontal and vertical) and seasonal patterns of diversity in coral recruits from Dabaisha and Guiwan reefs at Ludao, Taiwan. Concrete blocks supporting terra-cotta tiles were placed at shallow (15m) and mesophotic (40m) depths, during 2016-2018. Half of the tiles were retrieved and replaced biannually over three 6-month surveys (short-term); the remainder retrieved at the end of the 18-month (long-term) survey. 451 recruits were located using fluorescent censusing and identified by DNA barcoding. Barcoding the mitochondrial cytochrome oxidase I (COI) gene resulted in 17 molecular operational taxonomic units (MOTUs). To obtain taxonomic resolution to the generic level, Pocillopora were phylotyped using the mitochondrial open reading frame (ORF), resolving eight MOTUs. Acropora, Isopora, and Montipora recruits were identified by the nuclear PaxC intron, yielding ten MOTUs. Overall, 35 MOTUs were generated and were comprised primarily of Pocillopora and, in fewer numbers, Acropora, Isopora, Pavona, Montipora, Stylophora, among others. 40% of MOTUs recruited solely within mesophotic reefs while 20% were shared by both depth zones. MOTUs recruiting across a broad depth distribution appear consistent with the hypothesis of mesophotic reefs acting as a refuge for shallow-water coral reefs. In contrast, Acropora and Isopora MOTUs were structured across depth zones representing an exception to this hypothesis. This research provides an imperative assessment of coral recruitment in understudied mesophotic reefs and imparts insight into the refuge hypothesis.
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Affiliation(s)
- Derek Soto
- Biodiversity ProgramTaiwan International Graduate ProgramAcademia Sinica and National Taiwan Normal UniversityTaipeiTaiwan
- Biodiversity Research CenterAcademia SinicaTaipeiTaiwan
- Department of Life ScienceNational Taiwan Normal UniversityTaipeiTaiwan
| | - Stéphane De Palmas
- Biodiversity ProgramTaiwan International Graduate ProgramAcademia Sinica and National Taiwan Normal UniversityTaipeiTaiwan
- Biodiversity Research CenterAcademia SinicaTaipeiTaiwan
- Department of Life ScienceNational Taiwan Normal UniversityTaipeiTaiwan
| | - Ming‐Jay Ho
- Biodiversity Research CenterAcademia SinicaTaipeiTaiwan
- Green Island Marine Research StationAcademia SinicaLudao, Taitung CountyTaiwan
| | - Vianney Denis
- Institute of OceanographyNational Taiwan UniversityTaipeiTaiwan
| | - Chaolun Allen Chen
- Biodiversity Research CenterAcademia SinicaTaipeiTaiwan
- Department of Life ScienceNational Taiwan Normal UniversityTaipeiTaiwan
- Department of Life ScienceTung Hai UniversityTaichungTaiwan
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Bhagooli R, Mattan-Moorgawa S, Kaullysing D, Louis YD, Gopeechund A, Ramah S, Soondur M, Pilly SS, Beesoo R, Wijayanti DP, Bachok ZB, Monrás VC, Casareto BE, Suzuki Y, Baker AC. Chlorophyll fluorescence - A tool to assess photosynthetic performance and stress photophysiology in symbiotic marine invertebrates and seaplants. MARINE POLLUTION BULLETIN 2021; 165:112059. [PMID: 33677415 DOI: 10.1016/j.marpolbul.2021.112059] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Revised: 12/30/2020] [Accepted: 01/01/2021] [Indexed: 06/12/2023]
Abstract
Chlorophyll a fluorescence is increasingly being used as a rapid, non-invasive, sensitive and convenient indicator of photosynthetic performance in marine autotrophs. This review presents the methodology, applications and limitations of chlorophyll fluorescence in marine studies. The various chlorophyll fluorescence tools such as Pulse-Amplitude-Modulated (PAM) and Fast Repetition Rate (FRR) fluorometry used in marine scientific studies are discussed. Various commonly employed chlorophyll fluorescence parameters are elaborated. The application of chlorophyll fluorescence in measuring natural variations, stress, stress tolerance and acclimation/adaptation to changing environment in primary producers such as microalgae, macroalgae, seagrasses and mangroves, and marine symbiotic invertebrates, namely symbiotic sponges, hard corals and sea anemones, kleptoplastic sea slugs and giant clams is critically assessed. Stressors include environmental, biological, physical and chemical ones. The strengths, limitations and future perspectives of the use of chlorophyll fluorescence technique as an assessment tool in symbiotic marine organisms and seaplants are discussed.
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Affiliation(s)
- Ranjeet Bhagooli
- Department of Biosciences & Ocean Studies, Faculty of Science & Pole of Research Excellence, Sustainable Marine Biodiversity Research Group, University of Mauritius, Réduit 80837, Mauritius; The Biodiversity and Environment Institute, Réduit, Mauritius; The Society of Biology (Mauritius), Réduit, Mauritius; Institute of Oceanography and Environment (INOS), Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia.
| | - Sushma Mattan-Moorgawa
- Department of Biosciences & Ocean Studies, Faculty of Science & Pole of Research Excellence, Sustainable Marine Biodiversity Research Group, University of Mauritius, Réduit 80837, Mauritius; The Biodiversity and Environment Institute, Réduit, Mauritius
| | - Deepeeka Kaullysing
- Department of Biosciences & Ocean Studies, Faculty of Science & Pole of Research Excellence, Sustainable Marine Biodiversity Research Group, University of Mauritius, Réduit 80837, Mauritius; The Biodiversity and Environment Institute, Réduit, Mauritius
| | - Yohan Didier Louis
- Department of Biosciences & Ocean Studies, Faculty of Science & Pole of Research Excellence, Sustainable Marine Biodiversity Research Group, University of Mauritius, Réduit 80837, Mauritius
| | - Arvind Gopeechund
- Department of Biosciences & Ocean Studies, Faculty of Science & Pole of Research Excellence, Sustainable Marine Biodiversity Research Group, University of Mauritius, Réduit 80837, Mauritius; The Biodiversity and Environment Institute, Réduit, Mauritius
| | - Sundy Ramah
- Department of Biosciences & Ocean Studies, Faculty of Science & Pole of Research Excellence, Sustainable Marine Biodiversity Research Group, University of Mauritius, Réduit 80837, Mauritius
| | - Mouneshwar Soondur
- Department of Biosciences & Ocean Studies, Faculty of Science & Pole of Research Excellence, Sustainable Marine Biodiversity Research Group, University of Mauritius, Réduit 80837, Mauritius; The Biodiversity and Environment Institute, Réduit, Mauritius
| | - Sivajyodee Sannassy Pilly
- Department of Biosciences & Ocean Studies, Faculty of Science & Pole of Research Excellence, Sustainable Marine Biodiversity Research Group, University of Mauritius, Réduit 80837, Mauritius
| | - Rima Beesoo
- Department of Biosciences & Ocean Studies, Faculty of Science & Pole of Research Excellence, Sustainable Marine Biodiversity Research Group, University of Mauritius, Réduit 80837, Mauritius
| | | | - Zainudin Bin Bachok
- Institute of Oceanography and Environment (INOS), Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia
| | - Víctor Cubillos Monrás
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio Costero de Recursos Acuáticos de Calfuco, Universidad Austral de Chile, Valdivia, Chile
| | | | - Yoshimi Suzuki
- Shizuoka University, 836 Oya, Suruga, Shizuoka, Shizuoka, Japan
| | - Andrew Charles Baker
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA
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Slagel S, Lohr K, O'Neil K, Patterson J. Growth, calcification, and photobiology of the threatened coral Acropora cervicornis in natural versus artificial light. Zoo Biol 2021; 40:201-207. [PMID: 33544909 DOI: 10.1002/zoo.21589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 01/25/2021] [Indexed: 11/11/2022]
Abstract
Land-based coral culture is of increasing interest for conservation and educational display. Shallow water corals generate most of their energy from photosynthesis, and light is a critical abiotic factor in their husbandry. We compared growth, calcification, and photobiology in the coral Acropora cervicornis between natural and artificial (light-emitting diode; LED) light to better understand the impact of light source on coral performance. One tank of a greenhouse recirculating system at The Florida Aquarium's Center for Conservation was used to culture replicate coral colonies. Half of the tank and corals were covered to block sunlight and illuminated with a commercial reef aquarium LED fixture, while the other half was exposed to natural sunlight. Treatments were matched in terms of maximum photosynthetically active radiation and spectral measurements characterized both light regimes. Coral growth and calcification were tracked over a period of 19 weeks by repeated measurements of total linear extension (TLE) and buoyant weight. For the first 5 weeks, photosynthetic yield was measured weekly using a pulse-amplitude-modulated fluorometer. Calcification was significantly higher under LED lighting relative to natural light, but TLE did not differ. Photobiology data suggest that corals in both treatments were acclimated to the same light level, but photosynthetic efficiency was ultimately greater in the natural light treatment. More consistent light delivery and different spectral composition under LED treatment conditions may explain the incongruity between calcification and photosynthetic efficiency. This experiment informs husbandry of shallow-water scleractinian corals maintained in both natural sunlight and enclosed structures.
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Affiliation(s)
- Sebastian Slagel
- Program in Fisheries and Aquatic Sciences, School of Forest Resources and Conservation, University of Florida/IFAS, Gainesville, Florida, USA
| | - Kathryn Lohr
- Program in Fisheries and Aquatic Sciences, School of Forest Resources and Conservation, University of Florida/IFAS, Gainesville, Florida, USA
| | - Keri O'Neil
- Center for Conservation, The Florida Aquarium, Apollo Beach, Florida, USA
| | - Joshua Patterson
- Program in Fisheries and Aquatic Sciences, School of Forest Resources and Conservation, University of Florida/IFAS, Gainesville, Florida, USA.,Center for Conservation, The Florida Aquarium, Apollo Beach, Florida, USA
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Serôdio J, Campbell DA. Photoinhibition in optically thick samples: Effects of light attenuation on chlorophyll fluorescence-based parameters. J Theor Biol 2021; 513:110580. [PMID: 33444625 DOI: 10.1016/j.jtbi.2021.110580] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/15/2020] [Accepted: 01/04/2021] [Indexed: 11/25/2022]
Abstract
Oxygenic photoautotrophs are, paradoxically, subject to photoinhibition of their photosynthetic apparatus, in particular one of its major components, the Photosystem II (PSII). Photoinhibition is generalized across species, light conditions and habitats, imposing substantial metabolic costs that lower photosynthetic productivity and constrain the niches of photoautotrophy. As a process driven by light reaching PSII, light attenuation in optically thick samples influences both the actual extent, and the detection, of photoinhibition. Chlorophyll fluorescence is widely used to measure photoinhibition, but fluorescence-based parameters are affected by light attenuation of both downwelling incident radiation traversing the sample to reach PSII, and emitted fluorescence upwelling through the sample. We used modelling, experimental manipulation of within-sample light attenuation, and meta-analysis of published data, to show substantial, differential effects of light attenuation and depth-integration of emitted fluorescence upon measurements of photoinhibition. Numerical simulations and experimental manipulation of light attenuation indicated that PSII photoinactivation tracked using chlorophyll fluorescence can appear to be over three times lower than the inherent cellular susceptibility to photoinactivation, in optically-dense samples such as leaves or biofilms. The meta-analysis of published data showed that this general trend was unknowingly present in the literature, revealing an overall difference of more than five times between optically thick leaves and optically thin cell suspensions. Although fluorescence-based parameters may provide ecophysiologically relevant information for characterizing the sample as a whole, light attenuation and depth integration can vary between samples independently of their intrinsic physiology. They should be used with caution when aiming to quantify in absolute terms inherent photoinhibition-related parameters in optically thick samples.
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Affiliation(s)
- João Serôdio
- Department of Biology and CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| | - Douglas A Campbell
- Department of Biology, Mount Allison University, Sackville, Canada NB E4L 3G7, Canada
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May LA, Burnett AR, Miller CV, Pisarski E, Webster LF, Moffitt ZJ, Pennington P, Wirth E, Baker G, Ricker R, Woodley CM. Effect of Louisiana sweet crude oil on a Pacific coral, Pocillopora damicornis. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 222:105454. [PMID: 32179335 DOI: 10.1016/j.aquatox.2020.105454] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 01/23/2020] [Accepted: 02/27/2020] [Indexed: 06/10/2023]
Abstract
Recent oil spill responses such as the Deepwater Horizon event have underscored the need for crude oil ecotoxicological threshold data for shallow water corals to assist in natural resource damage assessments. We determined the toxicity of a mechanically agitated oil-seawater mixture (high-energy water-accommodated fraction, HEWAF) of a sweet crude oil on a branched stony coral, Pocillopora damicornis. We report the results of two experiments: a 96 h static renewal exposure experiment and a "pulse-chase" experiment of three short-term exposure durations followed by a recovery period in artificial seawater. Five endpoints were used to determine ecotoxicological values: 1) algal symbiont chlorophyll fluorescence, 2) a tissue regeneration assay and a visual health metric with three endpoints: 3) tissue integrity, 4) tissue color, and 5) polyp behavior. The sum of 50 entrained polycyclic aromatic hydrocarbons (tPAH50) was used as a proxy for oil exposure. For the 96 h exposure dose response experiment, dark-adapted maximum quantum yield (Fv/Fm) of the dinoflagellate symbionts was least affected by crude oil (EC50 = 913 μg/L tPAH50); light-adapted effective quantum yield (EQY) was more sensitive (EC50 = 428 μg/L tPAH50). In the health assessment, polyp behavior (EC50 = 27 μg/L tPAH50) was more sensitive than tissue integrity (EC50 = 806 μg/L tPAH50) or tissue color (EC50 = 926 μg/L tPAH50). Tissue regeneration proved to be a particularly sensitive measurement for toxicity effects (EC50 = 10 μg/L tPAH50). Short duration (6-24 h) exposures using 503 μg/L tPAH50 (average concentration) resulted in negative impacts to P. damicornis and its symbionts. Recovery of chlorophyll a fluorescence levels for 6-24 h oil exposures was observed in a few hours (Fv/Fm) to several days (EQY) following recovery in fresh seawater. The coral health assessments for tissue integrity and tissue color were not affected following short-term oil exposure durations, but the 96 h treatment duration resulted in significant decreases for both. A reduction in polyp behavior (extension) was observed for all treatment durations, with recovery observed for the short-term (6-24 h) exposures within 1-2 days following placement in fresh seawater. Wounded and intact fragments exposed to oil treatments were particularly sensitive, with significant delays observed in tissue regeneration. Estimating ecotoxicological values for P. damicornis exposed to crude oil HEWAFs provides a basis for natural resource damage assessments for oil spills in reef ecosystems. These data, when combined with ecotoxicological values for other coral reef species, will contribute to the development of species sensitivity models.
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Affiliation(s)
- Lisa A May
- Consolidated Safety Services, Inc. contractor for National Oceanic and Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Stressor Detection and Impacts Division, Hollings Marine Laboratory, 331 Ft. Johnson Rd., Charleston, SC, 29412, USA.
| | - Athena R Burnett
- Consolidated Safety Services, Inc. contractor for National Oceanic and Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Stressor Detection and Impacts Division, Hollings Marine Laboratory, 331 Ft. Johnson Rd., Charleston, SC, 29412, USA
| | - Carl V Miller
- Consolidated Safety Services, Inc. contractor for National Oceanic and Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Stressor Detection and Impacts Division, Hollings Marine Laboratory, 331 Ft. Johnson Rd., Charleston, SC, 29412, USA
| | - Emily Pisarski
- Consolidated Safety Services, Inc. contractor for National Oceanic and Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Stressor Detection and Impacts Division, Hollings Marine Laboratory, 331 Ft. Johnson Rd., Charleston, SC, 29412, USA
| | - Laura F Webster
- National Oceanic and Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Stressor Detection and Impacts Division, Hollings Marine Laboratory, 331 Fort Johnson Rd., Charleston, SC, 29412, USA
| | - Zachary J Moffitt
- Consolidated Safety Services, Inc. contractor for National Oceanic and Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Stressor Detection and Impacts Division, Hollings Marine Laboratory, 331 Ft. Johnson Rd., Charleston, SC, 29412, USA
| | - Paul Pennington
- National Oceanic and Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Stressor Detection and Impacts Division, 219 Ft. Johnson Rd., Charleston, SC, 29412, USA
| | - Edward Wirth
- National Oceanic and Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Stressor Detection and Impacts Division, Hollings Marine Laboratory, 331 Fort Johnson Rd., Charleston, SC, 29412, USA
| | - Greg Baker
- National Oceanic and Atmospheric Administration, National Ocean Service, Office of Response and Restoration, 1305 East West Highway, Room 10317, Silver Spring, MD, 20910, USA
| | - Robert Ricker
- National Oceanic and Atmospheric Administration, National Ocean Service, Office of Response and Restoration, Assessment and Restoration Division, 1410 Neotomas Ave., Suite 110, Santa Rosa, CA, 95405, USA
| | - Cheryl M Woodley
- National Oceanic and Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Stressor Detection and Impacts Division, Hollings Marine Laboratory, 331 Fort Johnson Rd., Charleston, SC, 29412, USA
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Cartaxana P, Morelli L, Jesus B, Calado G, Calado R, Cruz S. The photon menace: kleptoplast protection in the photosynthetic sea slug Elysia timida. ACTA ACUST UNITED AC 2019; 222:jeb.202580. [PMID: 31171599 DOI: 10.1242/jeb.202580] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 06/02/2019] [Indexed: 11/20/2022]
Abstract
Absorption of excessive light by photosymbiotic organisms leads to the production of reactive oxygen species that can damage both symbiont and host. This is highly relevant in sacoglossan sea slugs that host functional chloroplasts 'stolen' from their algal foods (kleptoplasts), because of limited repair capacities resulting from the absence of algal nuclear genes. Here, we experimentally demonstrate (i) a host-mediated photoprotection mechanism in the photosynthetic sea slug Elysia timida, characterized by the closure of the parapodia under high irradiance and the reduction of kleptoplast light exposure; and (ii) the activation of a reversible xanthophyll cycle in kleptoplasts, which allows excessive energy to be dissipated. The described mechanisms reduce photoinactivation under high irradiance. We conclude that both host-mediated behavioural and plastid-based physiological photoprotective mechanisms can mitigate oxidative stress induced by high light in E. timida These mechanisms may play an important role in the establishment of long-term photosynthetically active kleptoplasts.
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Affiliation(s)
- Paulo Cartaxana
- Departamento de Biologia & CESAM & ECOMARE, Universidade de Aveiro, 3810-193 Aveiro, Portugal
| | - Luca Morelli
- Departamento de Biologia & CESAM & ECOMARE, Universidade de Aveiro, 3810-193 Aveiro, Portugal
| | - Bruno Jesus
- Laboratoire Mer Molécules Santé, Faculté des Sciences et des Techniques, Université de Nantes, 44322 Nantes, France
| | - Gonçalo Calado
- Departamento de Ciências da Vida, Universidade Lusófona, 1749-024 Lisboa, Portugal
| | - Ricardo Calado
- Departamento de Biologia & CESAM & ECOMARE, Universidade de Aveiro, 3810-193 Aveiro, Portugal
| | - Sónia Cruz
- Departamento de Biologia & CESAM & ECOMARE, Universidade de Aveiro, 3810-193 Aveiro, Portugal
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