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Bowazolo C, Morse D. Ribosome profiling in the Symbiodiniacean dinoflagellate Fugacium kawagutii shows coordinated protein synthesis of enzymes in different pathways at different times of day. Mol Microbiol 2023; 120:462-471. [PMID: 37545098 DOI: 10.1111/mmi.15137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 07/19/2023] [Accepted: 07/21/2023] [Indexed: 08/08/2023]
Abstract
Dinoflagellates respond to daily changes in light and dark by changes in cellular metabolism, yet the mechanisms used are still unclear. For example, Fugacium (previously Symbiodinium) kawagutii shows little difference in the transcriptome between day and night suggesting little transcriptional control over gene expression. Here, we have performed ribosome profiling at 2 h intervals over a daily light-dark cycle to assess the degree to which protein synthesis rates might change over the daily cycle. The number of F. kawagutii coding sequences with significant differences in the number of ribosome-protected fragments (RPF) over the 24-h cycle was 2923 using JTK_Cycle and 3655 using ECHO. The majority of the regulated transcripts showed peak translation at the onset of the dark period. The regulated sequences were assigned to different KEGG pathways and transcripts that were translated at roughly the same time were termed concurrently regulated. Both analyses revealed concurrent regulation of many transcripts whose gene products were involved in spliceosome or lysosome biogenesis with peak translation rates around the onset of the dark period, while others, involved in nitrate metabolism and ribosomal proteins, were preferentially translated around the onset of the day phase or the end of the night phase, respectively. In addition, some sequences involved in DNA synthesis were preferentially translated at the end of the day. We conclude that light-dark cycles seem able to synchronize translation of some transcripts encoding proteins involved in a range of different cellular processes, and propose that these changes may help the cells adapt and alter their metabolism as a function of the time of day.
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Affiliation(s)
- Carl Bowazolo
- Département de Sciences Biologiques, Institut de Recherche en biologie Végétale, Université de Montréal, Montréal, Québec, Canada
| | - David Morse
- Département de Sciences Biologiques, Institut de Recherche en biologie Végétale, Université de Montréal, Montréal, Québec, Canada
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Häfker NS, Andreatta G, Manzotti A, Falciatore A, Raible F, Tessmar-Raible K. Rhythms and Clocks in Marine Organisms. ANNUAL REVIEW OF MARINE SCIENCE 2023; 15:509-538. [PMID: 36028229 DOI: 10.1146/annurev-marine-030422-113038] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The regular movements of waves and tides are obvious representations of the oceans' rhythmicity. But the rhythms of marine life span across ecological niches and timescales, including short (in the range of hours) and long (in the range of days and months) periods. These rhythms regulate the physiology and behavior of individuals, as well as their interactions with each other and with the environment. This review highlights examples of rhythmicity in marine animals and algae that represent important groups of marine life across different habitats. The examples cover ecologically highly relevant species and a growing number of laboratory model systems that are used to disentangle key mechanistic principles. The review introduces fundamental concepts of chronobiology, such as the distinction between rhythmic and endogenous oscillator-driven processes. It also addresses the relevance of studying diverse rhythms and oscillators, as well as their interconnection, for making better predictions of how species will respond to environmental perturbations, including climate change. As the review aims to address scientists from the diverse fields of marine biology, ecology, and molecular chronobiology, all of which have their own scientific terms, we provide definitions of key terms throughout the article.
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Affiliation(s)
- N Sören Häfker
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Vienna, Austria; ,
- Research Platform "Rhythms of Life," University of Vienna, Vienna BioCenter, Vienna, Austria
| | - Gabriele Andreatta
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Vienna, Austria; ,
- Research Platform "Rhythms of Life," University of Vienna, Vienna BioCenter, Vienna, Austria
| | - Alessandro Manzotti
- Laboratoire de Biologie du Chloroplaste et Perception de la Lumière chez les Microalgues, UMR 7141, CNRS, Sorbonne Université, Institut de Biologie Physico-Chimique, Paris, France;
| | - Angela Falciatore
- Laboratoire de Biologie du Chloroplaste et Perception de la Lumière chez les Microalgues, UMR 7141, CNRS, Sorbonne Université, Institut de Biologie Physico-Chimique, Paris, France;
| | - Florian Raible
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Vienna, Austria; ,
- Research Platform "Rhythms of Life," University of Vienna, Vienna BioCenter, Vienna, Austria
| | - Kristin Tessmar-Raible
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Vienna, Austria; ,
- Research Platform "Rhythms of Life," University of Vienna, Vienna BioCenter, Vienna, Austria
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
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Jadhav DB, Sriramkumar Y, Roy S. The enigmatic clock of dinoflagellates, is it unique? Front Microbiol 2022; 13:1004074. [PMID: 36338102 PMCID: PMC9627503 DOI: 10.3389/fmicb.2022.1004074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 09/29/2022] [Indexed: 12/01/2022] Open
Abstract
Dinoflagellate clocks are unique as they show no resemblance to any known model eukaryotic or prokaryotic clock architecture. Dinoflagellates are unicellular, photosynthetic, primarily marine eukaryotes are known for their unique biology and rhythmic physiology. Their physiological rhythms are driven by an internal oscillator whose molecular underpinnings are yet unknown. One of the primary reasons that slowed the progression of their molecular studies is their extremely large and repetitive genomes. Dinoflagellates are primary contributors to the global carbon cycle and oxygen levels, therefore, comprehending their internal clock architecture and its interaction with their physiology becomes a subject of utmost importance. The advent of high throughput Omics technology provided the momentum to understand the molecular architecture and functioning of the dinoflagellate clocks. We use these extensive databases to perform meta-analysis to reveal the status of clock components in dinoflagellates. In this article, we will delve deep into the various “Omics” studies that catered to various breakthroughs in the field of circadian biology in these organisms that were not possible earlier. The overall inference from these omics studies points toward an uncommon eukaryotic clock model, which can provide promising leads to understand the evolution of molecular clocks.
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Rinsky M, Weizman E, Ben-Asher HW, Eyal G, Zhu B, Levy O. Temporal gene expression patterns in the coral Euphyllia paradivisa reveal the complexity of biological clocks in the cnidarian-algal symbiosis. SCIENCE ADVANCES 2022; 8:eabo6467. [PMID: 36112690 PMCID: PMC9481131 DOI: 10.1126/sciadv.abo6467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 08/02/2022] [Indexed: 05/25/2023]
Abstract
Studying chronobiology in reef-building corals is challenging due to the tightly coupled symbiosis with their photosynthetic algae, Symbiodiniaceae. Although symbiosis requires metabolic synchronization and coordination of cellular processes in the holobiont, the cross-talk between the host and symbiont's clocks is still puzzling. Here, we use the mesophotic coral Euphyllia paradivisa to examine temporal gene expression patterns in symbiotic and aposymbiotic morphs exposed to natural light/dark cycles and constant darkness. Our comparative transcriptomic analyses revealed circadian and circatidal cycles of gene expression with a predominant diel pattern in both coral morphs. We found a substantial number of transcripts consistently rhythmic under both light conditions, including genes likely involved in the cnidarians' circadian clock, thus indicating that an endogenous clock, which can oscillate independently from the Symbiodiniaceae clock, exists in E. paradivisa. The analysis further manifests the remarkable impacts of symbiosis on transcriptional rhythms and implies that the algae's presence influences the host's biorhythm.
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Affiliation(s)
- Mieka Rinsky
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Eviatar Weizman
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Hiba Waldman Ben-Asher
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Gal Eyal
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
- ARC Centre of Excellence for Coral Reef Studies, School of Biological Sciences, University of Queensland St. Lucia, Queensland 4072, Australia
| | - Bokai Zhu
- Aging Institute of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
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Cuitun‐Coronado D, Rees H, Colmer J, Hall A, de Barros Dantas LL, Dodd AN. Circadian and diel regulation of photosynthesis in the bryophyte Marchantia polymorpha. PLANT, CELL & ENVIRONMENT 2022; 45:2381-2394. [PMID: 35611455 PMCID: PMC9546472 DOI: 10.1111/pce.14364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 05/20/2022] [Accepted: 05/21/2022] [Indexed: 05/10/2023]
Abstract
Circadian rhythms are 24-h biological cycles that align metabolism, physiology, and development with daily environmental fluctuations. Photosynthetic processes are governed by the circadian clock in both flowering plants and some cyanobacteria, but it is unclear how extensively this is conserved throughout the green lineage. We investigated the contribution of circadian regulation to aspects of photosynthesis in Marchantia polymorpha, a liverwort that diverged from flowering plants early in the evolution of land plants. First, we identified in M. polymorpha the circadian regulation of photosynthetic biochemistry, measured using two approaches (delayed fluorescence, pulse amplitude modulation fluorescence). Second, we identified that light-dark cycles synchronize the phase of 24 h cycles of photosynthesis in M. polymorpha, whereas the phases of different thalli desynchronize under free-running conditions. This might also be due to the masking of the underlying circadian rhythms of photosynthesis by light-dark cycles. Finally, we used a pharmacological approach to identify that chloroplast translation might be necessary for clock control of light-harvesting in M. polymorpha. We infer that the circadian regulation of photosynthesis is well-conserved amongst terrestrial plants.
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Affiliation(s)
- David Cuitun‐Coronado
- Department of Cell and Developmental BiologyJohn Innes CentreNorwichUK
- School of Biological SciencesUniversity of BristolBristolUK
| | | | | | | | | | - Antony N. Dodd
- Department of Cell and Developmental BiologyJohn Innes CentreNorwichUK
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Sun Y, Jiang L, Gong S, Diaz-Pulido G, Yuan X, Tong H, Huang L, Zhou G, Zhang Y, Huang H. Changes in physiological performance and protein expression in the larvae of the coral Pocillopora damicornis and their symbionts in response to elevated temperature and acidification. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:151251. [PMID: 34728194 DOI: 10.1016/j.scitotenv.2021.151251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 10/22/2021] [Accepted: 10/22/2021] [Indexed: 06/13/2023]
Abstract
Climate change causes ocean warming and acidification, which threaten coral reef ecosystems. Ocean warming and acidification cause bleaching and mortality, and decrease calcification in adult corals, leading to changes in the composition of coral communities; however, their interactive effects on coral larvae are not comprehensively understood. To examine the underlying molecular mechanisms of larval responses to elevated temperature and pCO2, we examined the physiological performance and protein expression profiles of Pocillopora damicornis at two temperatures (29 and 33 °C) and pCO2 levels (500 and 1000 μatm) for 5 d. Extensive physiological and proteomic changes were observed in coral larvae. The results indicated a significant decrease in net photosynthesis (PNET) and autotrophic capability (PNET/RD) of larvae exposed to elevated temperature but a marked increase in PNET and PNET/RD of larvae exposed to high pCO2 levels. Elevated temperature significantly reduced endosymbiont densities by 70% and photochemical efficiency, indicating that warming impaired host-symbiont symbiosis. Expression of photosynthesis-related proteins, the photosystem (PS) I reaction center subunits IV and XI as well as oxygen-evolving enhancer 1, was downregulated at higher temperatures in symbionts, whereas expression of the PS I iron‑sulfur center protein was increased under high pCO2 conditions. Furthermore, expression of phosphoribulokinase (involved in the Calvin cycle) and phosphoenolpyruvate carboxylase (related to the C4 pathway) was downregulated in symbionts under thermal stress; this finding suggests reduced carbon fixation at high temperatures. The abundance of carbonic anhydrase-associated proteins, which are predicted to exert biochemical roles in dissolved inorganic carbon transport in larvae, was reduced in coral host and symbionts at high temperatures. These results elucidate potential mechanisms underlying the responses of coral larvae exposed to elevated temperature and acidification and suggest an important role of symbionts in the response to warming and acidification.
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Affiliation(s)
- Youfang Sun
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong University of Science and Technology, Hong Kong 999077, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research and Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lei Jiang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong University of Science and Technology, Hong Kong 999077, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research and Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya 572000, China
| | - Sanqiang Gong
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Guillermo Diaz-Pulido
- School of Environment and Science, and Australian Rivers Institute - Coast & Estuaries, Nathan Campus, Griffith University, Brisbane, Nathan Campus, Queensland 4111, Australia
| | - Xiangcheng Yuan
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research and Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya 572000, China
| | - Haoya Tong
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong University of Science and Technology, Hong Kong 999077, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research and Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya 572000, China
| | - Lintao Huang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research and Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guowei Zhou
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research and Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya 572000, China
| | - Yuyang Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research and Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya 572000, China
| | - Hui Huang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; Sanya National Marine Ecosystem Research Station; Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572000, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research and Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya 572000, China.
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7
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Frankowiak K, Roniewicz E, Stolarski J. Photosymbiosis in Late Triassic scleractinian corals from the Italian Dolomites. PeerJ 2021; 9:e11062. [PMID: 33777534 PMCID: PMC7977380 DOI: 10.7717/peerj.11062] [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: 03/03/2020] [Accepted: 02/14/2021] [Indexed: 11/20/2022] Open
Abstract
During the Carnian, oligotrophic shallow-water regions of the western Tethys were occupied by small, coral-rich patch reefs. Scleractinian corals, which already contributed to the formation of the reef structure, owed their position most probably to the symbiosis with dinoflagellate algae (zooxanthellae). Using microstructural (regularity of growth increments) and geochemical (oxygen and carbon stable isotopes) criteria of zooxanthellae symbiosis, we investigated whether this partnership was widespread among Carnian scleractinians from the Italian Dolomites (locality Alpe di Specie). Although corals from this locality are renowned from excellent mineralogical preservation (aragonite), their skeletons were rigorously tested against traces of diagenesis Irrespective of their growth forms, well preserved skeletons of corals from the Dolomites, most frequently revealed regular growth bands (low values of coefficient of variation) typical of modern zooxanthellate corals. Paradoxically, some Carnian taxa (Thamnasteriomorpha frechi and Thamnasteriomorphasp.)with highly integrated thamnasterioid colonies which today are formed exclusively by zooxanthellate corals, showed irregular fine-scale growth bands (coefficient of variation of 40% and 41% respectively) that could suggest their asymbiotic status. However, similar irregular skeletal banding is known also in some modern agariciids (Leptoseris fragilis) which are symbiotic with zooxanthellae. This may point to a similar ecological adaptation of Triassic taxa with thamnasterioid colonies. Contrary to occasionally ambiguous interpretation of growth banding, all examined Carnian corals exhibited lack of distinct correlation between carbon (δ13C range between 0.81‰ and 5.81‰) and oxygen (δ18O values range between −4.21‰ and −1.06‰) isotope composition of the skeleton which is consistent with similar pattern in modern zooxanthellates. It is therefore highly likely, that Carnian scleractinian corals exhibited analogous ecological adaptations as modern symbiotic corals and that coral-algal symbiosis that spread across various clades of Scleractinia preceded the reef bloom at the end of the Triassic.
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Affiliation(s)
| | - Ewa Roniewicz
- Institute of Paleobiology, Polish Academy of Sciences, Warsaw, Poland
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Bates H, Zavafer A, Szabó M, Ralph PJ. The Phenobottle, an open-source photobioreactor platform for environmental simulation. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.102105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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9
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Rosenberg Y, Doniger T, Harii S, Sinniger F, Levy O. Demystifying Circalunar and Diel Rhythmicity in Acropora digitifera under Constant Dim Light. iScience 2019; 22:477-488. [PMID: 31835172 PMCID: PMC6926284 DOI: 10.1016/j.isci.2019.11.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 10/22/2019] [Accepted: 11/22/2019] [Indexed: 01/09/2023] Open
Abstract
Life on earth has evolved under constant environmental changes; in response to these changes, most organisms have developed an endogenous clock that allows them to anticipate daily and seasonal changes and adapt their biology accordingly. Light cycles synchronize biological rhythms and are controlled by an endogenous clock that is entrained by environmental cues. Light is known to play a key role in the biology of symbiotic corals as they exhibit many biological processes entrained by daily light patterns. In this study, we aimed at determining the effect of constant dim light on coral's perception of diel and monthly cycles. Our results show that under constant dim light corals display a loss of rhythmic processes and constant stimuli by light, which initiates signal transduction that results in an abnormal cell cycle, cell proliferation, and protein synthesis. The results emphasize how constant dim light can mask the biological clock of Acropora digitifera. Light entrains many biological processes governed by the endogenous clock Constant dim light overrides the biological clock of A. digitifera corals Artificial light impacts the processes that allow corals to thrive in our oceans The increase of artificial light in coastal areas is a growing threat to coral reefs
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Affiliation(s)
- Yael Rosenberg
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel.
| | - Tirza Doniger
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Saki Harii
- Tropical Biosphere Research Center, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan
| | - Frederic Sinniger
- Tropical Biosphere Research Center, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
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10
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Lee SJ, Morse D, Hijri M. Holobiont chronobiology: mycorrhiza may be a key to linking aboveground and underground rhythms. MYCORRHIZA 2019; 29:403-412. [PMID: 31190278 DOI: 10.1007/s00572-019-00903-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 06/05/2019] [Indexed: 06/09/2023]
Abstract
Circadian clocks are nearly ubiquitous timing mechanisms that can orchestrate rhythmic behavior and gene expression in a wide range of organisms. Clock mechanisms are becoming well understood in fungal, animal, and plant model systems, yet many of these organisms are surrounded by a complex and diverse microbiota which should be taken into account when examining their biology. Of particular interest are the symbiotic relationships between organisms that have coevolved over time, forming a unit called a holobiont. Several studies have now shown linkages between the circadian rhythms of symbiotic partners. Interrelated regulation of holobiont circadian rhythms seems thus important to coordinate shifts in activity over the day for all the partners. Therefore, we suggest that the classical view of "chronobiological individuals" should include "a holobiont" rather than an organism. Unfortunately, mechanisms that may regulate interspecies temporal acclimation and the evolution of the circadian clock in holobionts are far from being understood. For the plant holobiont, our understanding is particularly limited. In this case, the holobiont encompasses two different ecosystems, one above and the other below the ground, with the two potentially receiving timing information from different synchronizing signals (Zeitgebers). The arbuscular mycorrhizal (AM) symbiosis, formed by plant roots and fungi, is one of the oldest and most widespread associations between organisms. By mediating the nutritional flux between the plant and the many microbes in the soil, AM symbiosis constitutes the backbone of the plant holobiont. Even though the importance of the AM symbiosis has been well recognized in agricultural and environmental sciences, its circadian chronobiology remains almost completely unknown. We have begun to study the circadian clock of arbuscular mycorrhizal fungi, and we compile and here discuss the available information on the subject. We propose that analyzing the interrelated temporal organization of the AM symbiosis and determining its underlying mechanisms will advance our understanding of the role and coordination of circadian clocks in holobionts in general.
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Affiliation(s)
- Soon-Jae Lee
- Institut de Recherche en Biologie Végétale (IRBV), Université de Montréal, 4101 Rue Sherbrooke Est, Montréal, Québec, H1X 2B2, Canada
- Department of Ecology and Evolution, University of Lausanne, 1015, Lausanne, Switzerland
| | - David Morse
- Institut de Recherche en Biologie Végétale (IRBV), Université de Montréal, 4101 Rue Sherbrooke Est, Montréal, Québec, H1X 2B2, Canada
| | - Mohamed Hijri
- Institut de Recherche en Biologie Végétale (IRBV), Université de Montréal, 4101 Rue Sherbrooke Est, Montréal, Québec, H1X 2B2, Canada.
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11
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Haro S, Bohórquez J, Lara M, Garcia-Robledo E, González CJ, Crespo JM, Papaspyrou S, Corzo A. Diel patterns of microphytobenthic primary production in intertidal sediments: the role of photoperiod on the vertical migration circadian rhythm. Sci Rep 2019; 9:13376. [PMID: 31527648 PMCID: PMC6746711 DOI: 10.1038/s41598-019-49971-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 08/01/2019] [Indexed: 02/08/2023] Open
Abstract
Diel primary production patterns of intertidal microphytobenthos (MPB) have been attributed to short-term physiological changes in the photosynthetic apparatus or to diel changes in the photoautotrophic biomass in the sediment photic layer due to vertical migration. Diel changes in primary production and vertical migration are entrained by external factors like photoperiod and tides. However, the role of photoperiod and tides has not been experimentally separated to date. Here, we performed laboratory experiments with sediment cores kept in immersion, in the absence of tides, with photoperiod or under continuous light. Measurements of net production, made with O2 microsensors, and of spectral reflectance at the sediment surface showed that, in intertidal sediments, the photoperiod signal was the major driver of the diel patterns of net primary production and sediment oxygen availability through the vertical migration of the MPB photoautotrophic biomass. Vertical migration was controlled by an endogenous circadian rhythm entrained by photoperiod in the absence of tides. The pattern progressively disappeared after 3 days in continuous light but was immediately reset by photoperiod. Even though a potential contribution of a subjective in situ tidal signal cannot be completely discarded, Fourier and cross spectral analysis of temporal patterns indicated that the photosynthetic circadian rhythm was mainly characterized by light/dark migratory cycles.
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Affiliation(s)
- S Haro
- Department of Biology, University of Cádiz, Puerto Real, 11510, Spain. .,Instituto Universitario de Investigación Marina (INMAR), Universidad de Cádiz, Campus de Excelencia Internacional del Mar (CEIMAR). Campus Universitario de Puerto Real, Puerto Real (Cádiz), 11510, Spain.
| | - J Bohórquez
- Department of Biology, University of Cádiz, Puerto Real, 11510, Spain.,Instituto Universitario de Investigación Marina (INMAR), Universidad de Cádiz, Campus de Excelencia Internacional del Mar (CEIMAR). Campus Universitario de Puerto Real, Puerto Real (Cádiz), 11510, Spain
| | - M Lara
- Department of Biology, University of Cádiz, Puerto Real, 11510, Spain.,Instituto Universitario de Investigación Marina (INMAR), Universidad de Cádiz, Campus de Excelencia Internacional del Mar (CEIMAR). Campus Universitario de Puerto Real, Puerto Real (Cádiz), 11510, Spain
| | - E Garcia-Robledo
- Department of Biology, University of Cádiz, Puerto Real, 11510, Spain.,Instituto Universitario de Investigación Marina (INMAR), Universidad de Cádiz, Campus de Excelencia Internacional del Mar (CEIMAR). Campus Universitario de Puerto Real, Puerto Real (Cádiz), 11510, Spain
| | - C J González
- Division of Naval Support and Oceanography, Marine Hydrographic Institute, Spanish Navy, Cadiz, Spain
| | - J M Crespo
- Department of Biology, University of Cádiz, Puerto Real, 11510, Spain
| | - S Papaspyrou
- Department of Biology, University of Cádiz, Puerto Real, 11510, Spain.,Instituto Universitario de Investigación Marina (INMAR), Universidad de Cádiz, Campus de Excelencia Internacional del Mar (CEIMAR). Campus Universitario de Puerto Real, Puerto Real (Cádiz), 11510, Spain
| | - A Corzo
- Department of Biology, University of Cádiz, Puerto Real, 11510, Spain.,Instituto Universitario de Investigación Marina (INMAR), Universidad de Cádiz, Campus de Excelencia Internacional del Mar (CEIMAR). Campus Universitario de Puerto Real, Puerto Real (Cádiz), 11510, Spain
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12
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Leach WB, Carrier TJ, Reitzel AM. Diel patterning in the bacterial community associated with the sea anemone Nematostella vectensis. Ecol Evol 2019; 9:9935-9947. [PMID: 31534705 PMCID: PMC6745676 DOI: 10.1002/ece3.5534] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 06/11/2019] [Accepted: 07/22/2019] [Indexed: 12/12/2022] Open
Abstract
Microbes can play an important role in the physiology of animals by providing essential nutrients, inducing immune pathways, and influencing the specific species that compose the microbiome through competitive or facilitatory interactions. The community of microbes associated with animals can be dynamic depending on the local environment, and factors that influence the composition of the microbiome are essential to our understanding of how microbes may influence the biology of their animal hosts. Regularly repeated changes in the environment, such as diel lighting, can result in two different organismal responses: a direct response to the presence and absence of exogenous light and endogenous rhythms resulting from a molecular circadian clock, both of which can influence the associated microbiota. Here, we report how diel lighting and a potential circadian clock impacts the diversity and relative abundance of bacteria in the model cnidarian Nematostella vectensis using an amplicon-based sequencing approach. Comparisons of bacterial communities associated with anemones cultured in constant darkness and in light:dark conditions revealed that individuals entrained in the dark had a more diverse microbiota. Overall community composition showed little variation over a 24-hr period in either treatment; however, abundances of individual bacterial OTUs showed significant cycling in each treatment. A comparative analysis of genes involved in the innate immune system of cnidarians showed differential expression between lighting conditions in N. vectensis, with significant up-regulation during long-term darkness for a subset of genes. Together, our studies support a hypothesis that the bacterial community associated with this species is relatively stable under diel light conditions when compared with static conditions and that particular bacterial members may have time-dependent abundance that coincides with the diel photoperiod in an otherwise stable community.
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Affiliation(s)
- Whitney B. Leach
- Department of Biological SciencesUniversity of North Carolina at CharlotteCharlotteNCUSA
| | - Tyler J. Carrier
- Department of Biological SciencesUniversity of North Carolina at CharlotteCharlotteNCUSA
| | - Adam M. Reitzel
- Department of Biological SciencesUniversity of North Carolina at CharlotteCharlotteNCUSA
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13
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Zaheri B, Dagenais-Bellefeuille S, Song B, Morse D. Assessing Transcriptional Responses to Light by the Dinoflagellate Symbiodinium. Microorganisms 2019; 7:microorganisms7080261. [PMID: 31416260 PMCID: PMC6723345 DOI: 10.3390/microorganisms7080261] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 08/07/2019] [Accepted: 08/12/2019] [Indexed: 11/16/2022] Open
Abstract
The control of transcription is poorly understood in dinoflagellates, a group of protists whose permanently condensed chromosomes are formed without histones. Furthermore, while transcriptomes contain a number of proteins annotated as transcription factors, the majority of these are cold shock domain proteins which are also known to bind RNA, meaning the number of true transcription factors is unknown. Here we have assessed the transcriptional response to light in the photosynthetic species Symbiodinium kawagutii. We find that three genes previously reported to respond to light using qPCR do not show differential expression using northern blots or RNA-Seq. Interestingly, global transcript profiling by RNA-Seq at LD 0 (dawn) and LD 12 (dusk) found only seven light-regulated genes (FDR = 0.1). qPCR using three randomly selected genes out of the seven was only able to validate differential expression of two. We conclude that there is likely to be less light regulation of gene expression in dinoflagellates than previously thought and suggest that transcriptional responses to other stimuli should also be more thoroughly evaluated in this class of organisms.
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Affiliation(s)
- Bahareh Zaheri
- Institut de Recherche en Biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Montréal, QC H1X 2B2, Canada
| | - Steve Dagenais-Bellefeuille
- Institut de Recherche en Biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Montréal, QC H1X 2B2, Canada
| | - Bo Song
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China
| | - David Morse
- Institut de Recherche en Biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Montréal, QC H1X 2B2, Canada.
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14
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Guadagno CR, Ewers BE, Weinig C. Circadian Rhythms and Redox State in Plants: Till Stress Do Us Part. FRONTIERS IN PLANT SCIENCE 2018; 9:247. [PMID: 29556244 PMCID: PMC5844964 DOI: 10.3389/fpls.2018.00247] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 02/12/2018] [Indexed: 05/22/2023]
Abstract
A growing body of evidence demonstrates a significant relationship between cellular redox state and circadian rhythms. Each day these two vital components of plant biology influence one another, dictating the pace for metabolism and physiology. Diverse environmental stressors can disrupt this condition and, although plant scientists have made significant progress in re-constructing functional networks of plant stress responses, stress impacts on the clock-redox crosstalk is poorly understood. Inter-connected phenomena such as redox state and metabolism, internal and external environments, cellular homeostasis and rhythms can impede predictive understanding of coordinated regulation of plant stress response. The integration of circadian clock effects into predictive network models is likely to increase final yield and better predict plant responses to stress. To achieve such integrated understanding, it is necessary to consider the internal clock not only as a gatekeeper of environmental responses but also as a target of stress syndromes. Using chlorophyll fluorescence as a reliable and high-throughput probe of stress coupled to functional genomics and metabolomics will provide insights on the crosstalk across a wide range of stress severity and duration, including potential insights into oxidative stress response and signaling. We suggest the efficiency of photosystem II in light conditions (Fv'/Fm') to be the most dynamic of the fluorescence variables and therefore the most reliable parameter to follow the stress response from early sensing to mortality.
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Affiliation(s)
| | - Brent E. Ewers
- Department of Botany, University of Wyoming, Laramie, WY, United States
- Program in Ecology, University of Wyoming, Laramie, WY, United States
| | - Cynthia Weinig
- Department of Botany, University of Wyoming, Laramie, WY, United States
- Program in Ecology, University of Wyoming, Laramie, WY, United States
- Department of Molecular and Cellular Life Sciences, University of Wyoming, Laramie, WY, United States
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15
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Fujise L, Nitschke MR, Frommlet JC, Serôdio J, Woodcock S, Ralph PJ, Suggett DJ. Cell Cycle Dynamics of Cultured Coral Endosymbiotic Microalgae (
Symbiodinium
) Across Different Types (Species) Under Alternate Light and Temperature Conditions. J Eukaryot Microbiol 2018; 65:505-517. [DOI: 10.1111/jeu.12497] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 12/17/2017] [Accepted: 12/19/2017] [Indexed: 01/02/2023]
Affiliation(s)
- Lisa Fujise
- Climate Change Cluster University of Technology Sydney Broadway New South Wales 2007 Australia
| | - Matthew R. Nitschke
- Climate Change Cluster University of Technology Sydney Broadway New South Wales 2007 Australia
- Department of Biology and Center for Environmental and Marine Studies University of Aveiro Aveiro 3810‐193 Portugal
| | - Jörg C. Frommlet
- Department of Biology and Center for Environmental and Marine Studies University of Aveiro Aveiro 3810‐193 Portugal
| | - João Serôdio
- Department of Biology and Center for Environmental and Marine Studies University of Aveiro Aveiro 3810‐193 Portugal
| | - Stephen Woodcock
- Climate Change Cluster University of Technology Sydney Broadway New South Wales 2007 Australia
| | - Peter J. Ralph
- Climate Change Cluster University of Technology Sydney Broadway New South Wales 2007 Australia
| | - David J. Suggett
- Climate Change Cluster University of Technology Sydney Broadway New South Wales 2007 Australia
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16
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Hidasi N, Belay A. Diurnal variation of various culture and biochemical parameters of Arthrospira platensis in large-scale outdoor raceway ponds. ALGAL RES 2018. [DOI: 10.1016/j.algal.2017.08.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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17
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García-Plazaola JI, Fernández-Marín B, Ferrio JP, Alday JG, Hoch G, Landais D, Milcu A, Tissue DT, Voltas J, Gessler A, Roy J, Resco de Dios V. Endogenous circadian rhythms in pigment composition induce changes in photochemical efficiency in plant canopies. PLANT, CELL & ENVIRONMENT 2017; 40:1153-1162. [PMID: 28098350 DOI: 10.1111/pce.12909] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 01/03/2017] [Accepted: 01/04/2017] [Indexed: 05/16/2023]
Abstract
There is increasing evidence that the circadian clock is a significant driver of photosynthesis that becomes apparent when environmental cues are experimentally held constant. We studied whether the composition of photosynthetic pigments is under circadian regulation, and whether pigment oscillations lead to rhythmic changes in photochemical efficiency. To address these questions, we maintained canopies of bean and cotton, after an entrainment phase, under constant (light or darkness) conditions for 30-48 h. Photosynthesis and quantum yield peaked at subjective noon, and non-photochemical quenching peaked at night. These oscillations were not associated with parallel changes in carbohydrate content or xanthophyll cycle activity. We observed robust oscillations of Chl a/b during constant light in both species, and also under constant darkness in bean, peaking when it would have been night during the entrainment (subjective nights). These oscillations could be attributed to the synthesis and/or degradation of trimeric light-harvesting complex II (reflected by the rhythmic changes in Chl a/b), with the antenna size minimal at night and maximal around subjective noon. Considering together the oscillations of pigments and photochemistry, the observed pattern of changes is counterintuitive if we assume that the plant strategy is to avoid photodamage, but consistent with a strategy where non-stressed plants maximize photosynthesis.
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Affiliation(s)
| | - Beatriz Fernández-Marín
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), 48080, Bilbao, Spain
- Institute of Botany, University of Innsbruck, A6020, Innsbruck, Austria
| | - Juan Pedro Ferrio
- Department of Crop and Forest Sciences-AGROTECNIO Center, Universitat de Lleida, 25198, Lleida, Spain
- Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - Josu G Alday
- Department of Crop and Forest Sciences-AGROTECNIO Center, Universitat de Lleida, 25198, Lleida, Spain
| | - Günter Hoch
- Department of Environmental Sciences - Botany, University of Basel, Schönbeinstrasse 6, 4056, Basel, Switzerland
| | - Damien Landais
- Ecotron Européen de Montpellier, CNRS, UPS-3248, Montferrier-sur-Lez, France
| | - Alexandru Milcu
- Ecotron Européen de Montpellier, CNRS, UPS-3248, Montferrier-sur-Lez, France
- Centre d'Ecologie Fonctionnelle et Evolutive, CEFE-CNRS, UMR-5175, Université de Montpellier - Université Paul Valéry - EPHE, 1919 route de Mende, F-34293, Montpellier Cedex 5, France
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, 2753, New South Wales, Australia
| | - Jordi Voltas
- Department of Crop and Forest Sciences-AGROTECNIO Center, Universitat de Lleida, 25198, Lleida, Spain
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research, 8903, Birmensdorf, Switzerland
- Institute for Landscape Biogeochemistry, Leibniz-Centre for Agricultural Landscape Research (ZALF), 15374, Müncheberg, Germany
| | - Jacques Roy
- Ecotron Européen de Montpellier, CNRS, UPS-3248, Montferrier-sur-Lez, France
| | - Víctor Resco de Dios
- Department of Crop and Forest Sciences-AGROTECNIO Center, Universitat de Lleida, 25198, Lleida, Spain
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, 2753, New South Wales, Australia
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18
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Rasmusson LM, Lauritano C, Procaccini G, Gullström M, Buapet P, Björk M. Respiratory oxygen consumption in the seagrass Zostera marina varies on a diel basis and is partly affected by light. MARINE BIOLOGY 2017; 164:140. [PMID: 28596620 PMCID: PMC5446554 DOI: 10.1007/s00227-017-3168-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 05/17/2017] [Indexed: 06/07/2023]
Abstract
The seagrass Zostera marina is an important marine ecosystem engineer, greatly influencing oxygen and carbon fluctuations in temperate coastal areas. Although photosynthetically driven gas fluxes are well studied, the impact of the plant's mitochondrial respiration on overall CO2 and O2 fluxes in marine vegetated areas is not yet understood. Likewise, the gene expression in relation to the respiratory pathway has not been well analyzed in seagrasses. This study uses a combined approach, studying respiratory oxygen consumption rates in darkness simultaneously with changes in gene expression, with the aim of examining how respiratory oxygen consumption fluctuates on a diel basis. Measurements were first made in a field study where samples were taken directly from the ocean to the laboratory for estimations of respiratory rates. This was followed by a laboratory study where measurements of respiration and expression of genes known to be involved in mitochondrial respiration were conducted for 5 days under light conditions mimicking natural summer light (i.e., 15 h of light and 9 h of darkness), followed by 3 days of constant darkness to detect the presence of a potential circadian clock. In the field study, there was a clear diel variation in respiratory oxygen consumption with the highest rates in the late evening and at night (0.766 and 0.869 µmol O2 m-2 s-1, respectively). These repetitive diel patterns were not seen in the laboratory, where water conditions (temperature, pH, and oxygen) showed minor fluctuations and only light varied. The gene expression analysis did not give clear evidence on drivers behind the respiratory fluxes; however, expression levels of the selected genes generally increased when the seagrass was kept in constant darkness. While light may influence mitochondrial respiratory fluxes, it appears that other environmental factors (e.g., temperature, pH, or oxygen) could be of significance too. As seagrasses substantially alter the proportions of both oxygen and inorganic carbon in the water column and respiration is a great driver of these alterations, we propose that acknowledging the presence of respiratory fluctuations in nature should be considered when estimating coastal carbon budgets. As dark respiration in field at midnight was approximately doubled from that of midday, great over-, or underestimations of the respiratory carbon dioxide release from seagrasses could be made if values are just obtained at one specific time point and considered constant.
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Affiliation(s)
- Lina M. Rasmusson
- Seagrass Ecology and Physiology Research Group, Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Chiara Lauritano
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Gabriele Procaccini
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Martin Gullström
- Seagrass Ecology and Physiology Research Group, Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Pimchanok Buapet
- Seagrass Ecology and Physiology Research Group, Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
- Department of Biology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112 Thailand
| | - Mats Björk
- Seagrass Ecology and Physiology Research Group, Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
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19
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Louis YD, Bhagooli R, Kenkel CD, Baker AC, Dyall SD. Gene expression biomarkers of heat stress in scleractinian corals: Promises and limitations. Comp Biochem Physiol C Toxicol Pharmacol 2017; 191:63-77. [PMID: 27585119 DOI: 10.1016/j.cbpc.2016.08.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Revised: 08/02/2016] [Accepted: 08/21/2016] [Indexed: 12/13/2022]
Abstract
Gene expression biomarkers (GEBs) are emerging as powerful diagnostic tools for identifying and characterizing coral stress. Their capacity to detect sublethal stress prior to the onset of signs at the organismal level that might already indicate significant damage makes them more precise and proactive compared to traditional monitoring techniques. A high number of candidate GEBs, including certain heat shock protein genes, metabolic genes, oxidative stress genes, immune response genes, ion transport genes, and structural genes have been investigated, and some genes, including hsp16, Cacna1, MnSOD, SLC26, and Nf-kB, are already showing excellent potential as reliable indicators of thermal stress in corals. In this mini-review, we synthesize the current state of knowledge of scleractinian coral GEBs and highlight gaps in our understanding that identify directions for future work. We also address the underlying sources of variation that have sometimes led to contrasting results between studies, such as differences in experimental set-up and approach, intrinsic variation in the expression profiles of different experimental organisms (such as between different colonies or their algal symbionts), diel cycles, varying thermal history, and different expression thresholds. Despite advances in our understanding there is still no universally accepted biomarker of thermal stress, the molecular response of corals to heat stress is still unclear, and biomarker research in Symbiodinium still lags behind that of the host. These gaps should be addressed in future work.
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Affiliation(s)
- Yohan D Louis
- Department of Biosciences, Faculty of Science, University of Mauritius, Réduit 80837, Mauritius
| | - Ranjeet Bhagooli
- Department of Marine & Ocean Science, Fisheries & Mariculture, Faculty of Ocean Studies, University of Mauritius, Réduit 80837, Mauritius.
| | - Carly D Kenkel
- Australian Institute of Marine Science, PMB No. 3, Townsville MC, QLD 4810, Australia
| | - Andrew C Baker
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Cswy., Miami, FL, USA
| | - Sabrina D Dyall
- Department of Biosciences, Faculty of Science, University of Mauritius, Réduit 80837, Mauritius
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20
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Uncovering Spatio-Temporal and Treatment-Derived Differences in the Molecular Physiology of a Model Coral-Dinoflagellate Mutualism with Multivariate Statistical Approaches. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2016. [DOI: 10.3390/jmse4030063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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21
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Heath-Heckman EAC. The Metronome of Symbiosis: Interactions Between Microbes and the Host Circadian Clock. Integr Comp Biol 2016; 56:776-783. [PMID: 27371387 DOI: 10.1093/icb/icw067] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The entrainment of circadian rhythms, physiological cycles with a period of about 24 h, is regulated by a variety of mechanisms, including nonvisual photoreception. While circadian rhythms have been shown to be integral to many processes in multicellular organisms, including immune regulation, the effect of circadian rhythms on symbiosis, or host-microbe interactions, has only recently begun to be studied. This review summarizes recent work in the interactions of both pathogenic and mutualistic associations with host and symbiont circadian rhythms, focusing specifically on three mutualistic systems in which this phenomenon has been best studied. One important theme taken from these studies is the fact that mutualisms are profoundly affected by the circadian rhythms of the host, but that the microbial symbionts in these associations can, in turn, manipulate host rhythms. The interplay between circadian rhythms and symbiosis is a promising new field with effects that should be kept in mind when designing future studies across biology.
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22
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Hawkins TD, Hagemeyer JCG, Hoadley KD, Marsh AG, Warner ME. Partitioning of Respiration in an Animal-Algal Symbiosis: Implications for Different Aerobic Capacity between Symbiodinium spp. Front Physiol 2016; 7:128. [PMID: 27148067 PMCID: PMC4834350 DOI: 10.3389/fphys.2016.00128] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 03/22/2016] [Indexed: 11/29/2022] Open
Abstract
Cnidarian-dinoflagellate symbioses are ecologically important and the subject of much investigation. However, our understanding of critical aspects of symbiosis physiology, such as the partitioning of total respiration between the host and symbiont, remains incomplete. Specifically, we know little about how the relationship between host and symbiont respiration varies between different holobionts (host-symbiont combinations). We applied molecular and biochemical techniques to investigate aerobic respiratory capacity in naturally symbiotic Exaiptasia pallida sea anemones, alongside animals infected with either homologous ITS2-type A4 Symbiodinium or a heterologous isolate of Symbiodinium minutum (ITS2-type B1). In naturally symbiotic anemones, host, symbiont, and total holobiont mitochondrial citrate synthase (CS) enzyme activity, but not host mitochondrial copy number, were reliable predictors of holobiont respiration. There was a positive association between symbiont density and host CS specific activity (mg protein−1), and a negative correlation between host- and symbiont CS specific activities. Notably, partitioning of total CS activity between host and symbiont in this natural E. pallida population was significantly different to the host/symbiont biomass ratio. In re-infected anemones, we found significant between-holobiont differences in the CS specific activity of the algal symbionts. Furthermore, the relationship between the partitioning of total CS activity and the host/symbiont biomass ratio differed between holobionts. These data have broad implications for our understanding of cnidarian-algal symbiosis. Specifically, the long-held assumption of equivalency between symbiont/host biomass and respiration ratios can result in significant overestimation of symbiont respiration and potentially erroneous conclusions regarding the percentage of carbon translocated to the host. The interspecific variability in symbiont aerobic capacity provides further evidence for distinct physiological differences that should be accounted for when studying diverse host-symbiont combinations.
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Affiliation(s)
- Thomas D Hawkins
- College of Earth, Ocean and Environment, School of Marine Science and Policy, University of Delaware Lewes, DE, USA
| | - Julia C G Hagemeyer
- College of Earth, Ocean and Environment, School of Marine Science and Policy, University of Delaware Lewes, DE, USA
| | - Kenneth D Hoadley
- College of Earth, Ocean and Environment, School of Marine Science and Policy, University of Delaware Lewes, DE, USA
| | - Adam G Marsh
- College of Earth, Ocean and Environment, School of Marine Science and Policy, University of Delaware Lewes, DE, USA
| | - Mark E Warner
- College of Earth, Ocean and Environment, School of Marine Science and Policy, University of Delaware Lewes, DE, USA
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23
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Gutner-Hoch E, Schneider K, Stolarski J, Domart-Coulon I, Yam R, Meibom A, Shemesh A, Levy O. Evidence for Rhythmicity Pacemaker in the Calcification Process of Scleractinian Coral. Sci Rep 2016; 6:20191. [PMID: 26847144 PMCID: PMC4742845 DOI: 10.1038/srep20191] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 12/17/2015] [Indexed: 11/09/2022] Open
Abstract
Reef-building scleractinian (stony) corals are among the most efficient bio-mineralizing organisms in nature. The calcification rate of scleractinian corals oscillates under ambient light conditions, with a cyclic, diurnal pattern. A fundamental question is whether this cyclic pattern is controlled by exogenous signals or by an endogenous 'biological-clock' mechanism, or both. To address this problem, we have studied calcification patterns of the Red Sea scleractinian coral Acropora eurystoma with frequent measurements of total alkalinity (AT) under different light conditions. Additionally, skeletal extension and ultra-structure of newly deposited calcium carbonate were elucidated with (86)Sr isotope labeling analysis, combined with NanoSIMS ion microprobe and scanning electron microscope imaging. Our results show that the calcification process persists with its cyclic pattern under constant light conditions while dissolution takes place within one day of constant dark conditions, indicating that an intrinsic, light-entrained mechanism may be involved in controlling the calcification process in photosymbiotic corals.
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Affiliation(s)
- Eldad Gutner-Hoch
- The Mina &Everard Goodman Faculty of Life Sciences, Bar-Ilan University, 52900 Ramat-Gan, Israel
| | - Kenneth Schneider
- The Mina &Everard Goodman Faculty of Life Sciences, Bar-Ilan University, 52900 Ramat-Gan, Israel
| | - Jaroslaw Stolarski
- Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, PL-00-818 Warsaw, Poland
| | - Isabelle Domart-Coulon
- MCAM UMR7245, Sorbonne Universités, Muséum National d'Histoire Naturelle, (CP54) 57 rue Cuvier, 75005 Paris, France
| | - Ruth Yam
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, P.O.Box 26, 76100 Rehovot, Israel
| | - Anders Meibom
- Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.,Center for Advanced Surface Analysis, Institute of Earth Sciences, University of Lausanne, Lausanne, Switzerland
| | - Aldo Shemesh
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, P.O.Box 26, 76100 Rehovot, Israel
| | - Oren Levy
- The Mina &Everard Goodman Faculty of Life Sciences, Bar-Ilan University, 52900 Ramat-Gan, Israel
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24
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Frankowiak K, Kret S, Mazur M, Meibom A, Kitahara MV, Stolarski J. Fine-Scale Skeletal Banding Can Distinguish Symbiotic from Asymbiotic Species among Modern and Fossil Scleractinian Corals. PLoS One 2016; 11:e0147066. [PMID: 26751803 PMCID: PMC4713449 DOI: 10.1371/journal.pone.0147066] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 12/27/2015] [Indexed: 12/27/2022] Open
Abstract
Understanding the evolution of scleractinian corals on geological timescales is key to predict how modern reef ecosystems will react to changing environmental conditions in the future. Important to such efforts has been the development of several skeleton-based criteria to distinguish between the two major ecological groups of scleractinians: zooxanthellates, which live in symbiosis with dinoflagellate algae, and azooxanthellates, which lack endosymbiotic dinoflagellates. Existing criteria are based on overall skeletal morphology and bio/geo-chemical indicators-none of them being particularly robust. Here we explore another skeletal feature, namely fine-scale growth banding, which differs between these two groups of corals. Using various ultra-structural imaging techniques (e.g., TEM, SEM, and NanoSIMS) we have characterized skeletal growth increments, composed of doublets of optically light and dark bands, in a broad selection of extant symbiotic and asymbiotic corals. Skeletons of zooxanthellate corals are characterized by regular growth banding, whereas in skeletons of azooxanthellate corals the growth banding is irregular. Importantly, the regularity of growth bands can be easily quantified with a coefficient of variation obtained by measuring bandwidths on SEM images of polished and etched skeletal surfaces of septa and/or walls. We find that this coefficient of variation (lower values indicate higher regularity) ranges from ~40 to ~90% in azooxanthellate corals and from ~5 to ~15% in symbiotic species. With more than 90% (28 out of 31) of the studied corals conforming to this microstructural criterion, it represents an easy and robust method to discriminate between zooxanthellate and azooxanthellate corals. This microstructural criterion has been applied to the exceptionally preserved skeleton of the Triassic (Norian, ca. 215 Ma) scleractinian Volzeia sp., which contains the first example of regular, fine-scale banding of thickening deposits in a fossil coral of this age. The regularity of its growth banding strongly suggests that the coral was symbiotic with zooxanthellates.
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Affiliation(s)
- Katarzyna Frankowiak
- Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, PL-00-818 Warsaw, Poland
| | - Sławomir Kret
- Institute of Physics, Polish Academy of Sciences, Lotników 32/46, PL-02-668 Warsaw, Poland
| | - Maciej Mazur
- Department of Chemistry, University of Warsaw, Pasteura 1, PL-02-093 Warsaw, Poland
| | - Anders Meibom
- Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Center for Advanced Surface Analysis, Institute of Earth Sciences, Université de Lausanne, CH-1015 Lausanne, Switzerland
| | - Marcelo V. Kitahara
- Departamento de Cięncias do Mar, Universidade Federal de SăoPaulo, Campus Baixada Santista, 11030–400 Santos, Brasil
| | - Jarosław Stolarski
- Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, PL-00-818 Warsaw, Poland
- * E-mail:
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Comparing the diel vertical migration of Karlodinium veneficum (dinophyceae) and Chattonella subsalsa (Raphidophyceae): PSII photochemistry, circadian control, and carbon assimilation. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 143:107-19. [PMID: 25618815 DOI: 10.1016/j.jphotobiol.2014.12.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 12/06/2014] [Accepted: 12/18/2014] [Indexed: 11/23/2022]
Abstract
Diel vertical migration (DVM) is thought to provide an adaptive advantage to some phytoplankton, and may help determine the ecological niche of certain harmful algae. Here we separately compared DVM patterns between two species of harmful algae isolated from the Delaware Inland Bays, Karlodinium veneficum and Chattonella subsalsa, in laboratory columns. We interpreted the DVM patterns of each species with Photosystem II (PSII) photochemistry, rates of carbon assimilation, and specific growth rates. Each species migrated differently, wherein K. veneficum migrated closer to the surface each day with high population synchrony, while C. subsalsa migrated near to the surface from the first day of measurements with low population synchrony. Both species appeared to downregulate PSII in high light at the surface, but by different mechanisms. C. subsalsa grew slower than K. veneficum in low light intensities (≈bottom of columns), and exhibited maximal rates of C-assimilation (Pmax) at surface light intensities, suggesting this species may prefer high light, potentially explaining this species' rapid surface migration. Contrastingly, K. veneficum showed declines in carbon assimilation at surface light intensities, and exhibited a smaller reduction in growth at low (bottom) light intensities (compared to C. subsalsa), suggesting that this species' step-wise migration was photoacclimative and determined daily migration depth. DVM was found to be under circadian control in C. subsalsa, but not in K. veneficum. However, there was little evidence for circadian regulation of PSII photochemistry in either species. Migration conformed to each species' physiology, and the results contribute to our understanding each alga's realized environmental niche.
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26
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Abstract
As major contributors to global oxygen levels and producers of fatty acids, carotenoids, sterols, and phycocolloids, algae have significant ecological and commercial roles. Early algal models have contributed much to our understanding of circadian clocks at physiological and biochemical levels. The genetic and molecular approaches that identified clock components in other taxa have not been as widely applied to algae. We review results from seven species: the chlorophytes Chlamydomonas reinhardtii, Ostreococcus tauri, and Acetabularia spp.; the dinoflagellates Lingulodinium polyedrum and Symbiodinium spp.; the euglenozoa Euglena gracilis; and the red alga Cyanidioschyzon merolae. The relative simplicity, experimental tractability, and ecological and evolutionary diversity of algal systems may now make them particularly useful in integrating quantitative data from "omic" technologies (e.g., genomics, transcriptomics, metabolomics, and proteomics) with computational and mathematical methods.
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Affiliation(s)
- Zeenat B Noordally
- SynthSys and School of Biological Sciences, University of Edinburgh , Edinburgh EH9 3BF, United Kingdom
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27
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Bosch TCG, Adamska M, Augustin R, Domazet-Loso T, Foret S, Fraune S, Funayama N, Grasis J, Hamada M, Hatta M, Hobmayer B, Kawai K, Klimovich A, Manuel M, Shinzato C, Technau U, Yum S, Miller DJ. How do environmental factors influence life cycles and development? An experimental framework for early-diverging metazoans. Bioessays 2014; 36:1185-94. [PMID: 25205353 DOI: 10.1002/bies.201400065] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Ecological developmental biology (eco-devo) explores the mechanistic relationships between the processes of individual development and environmental factors. Recent studies imply that some of these relationships have deep evolutionary origins, and may even pre-date the divergences of the simplest extant animals, including cnidarians and sponges. Development of these early diverging metazoans is often sensitive to environmental factors, and these interactions occur in the context of conserved signaling pathways and mechanisms of tissue homeostasis whose detailed molecular logic remain elusive. Efficient methods for transgenesis in cnidarians together with the ease of experimental manipulation in cnidarians and sponges make them ideal models for understanding causal relationships between environmental factors and developmental mechanisms. Here, we identify major questions at the interface between animal evolution and development and outline a road map for research aimed at identifying the mechanisms that link environmental factors to developmental mechanisms in early diverging metazoans. Also watch the Video Abstract.
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28
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Roth MS. The engine of the reef: photobiology of the coral-algal symbiosis. Front Microbiol 2014; 5:422. [PMID: 25202301 PMCID: PMC4141621 DOI: 10.3389/fmicb.2014.00422] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 07/25/2014] [Indexed: 01/09/2023] Open
Abstract
Coral reef ecosystems thrive in tropical oligotrophic oceans because of the relationship between corals and endosymbiotic dinoflagellate algae called Symbiodinium. Symbiodinium convert sunlight and carbon dioxide into organic carbon and oxygen to fuel coral growth and calcification, creating habitat for these diverse and productive ecosystems. Light is thus a key regulating factor shaping the productivity, physiology, and ecology of the coral holobiont. Similar to all oxygenic photoautotrophs, Symbiodinium must safely harvest sunlight for photosynthesis and dissipate excess energy to prevent oxidative stress. Oxidative stress is caused by environmental stressors such as those associated with global climate change, and ultimately leads to breakdown of the coral-algal symbiosis known as coral bleaching. Recently, large-scale coral bleaching events have become pervasive and frequent threatening and endangering coral reefs. Because the coral-algal symbiosis is the biological engine producing the reef, the future of coral reef ecosystems depends on the ecophysiology of the symbiosis. This review examines the photobiology of the coral-algal symbiosis with particular focus on the photophysiological responses and timescales of corals and Symbiodinium. Additionally, this review summarizes the light environment and its dynamics, the vulnerability of the symbiosis to oxidative stress, the abiotic and biotic factors influencing photosynthesis, the diversity of the coral-algal symbiosis, and recent advances in the field. Studies integrating physiology with the developing "omics" fields will provide new insights into the coral-algal symbiosis. Greater physiological and ecological understanding of the coral-algal symbiosis is needed for protection and conservation of coral reefs.
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Affiliation(s)
- Melissa S. Roth
- Department of Plant and Microbial Biology, University of California BerkeleyBerkeley, CA, USA
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29
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Circadian clocks in symbiotic corals: The duet between Symbiodinium algae and their coral host. Mar Genomics 2014; 14:47-57. [DOI: 10.1016/j.margen.2014.01.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 11/11/2013] [Accepted: 01/13/2014] [Indexed: 12/15/2022]
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30
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Yamada N, Tanaka A, Horiguchi T. cPPB-aE is discovered from photosynthetic benthic dinoflagellates. JOURNAL OF PHYCOLOGY 2014; 50:101-107. [PMID: 26988011 DOI: 10.1111/jpy.12135] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 09/24/2013] [Indexed: 06/05/2023]
Abstract
Although chlorophyll degradation pathways in higher plants have been well studied, little is known about the mechanisms of chlorophyll degradation in microalgae. In this article, we report the occurrence of a chlorophyll a derivative that has never been discovered in photosynthetic organisms. This chlorophyll derivative emits no fluorescence and has a peculiar absorbance peak at 425, 451, 625, and 685 nm. From these features, it was identified as 13(2) ,17(3) -cyclopheophorbide a enol (cPPB-aE), reported as a degradation product of chlorophyll a derived from prey algal cells in heterotrophic protists. We discovered cPPB-aE in six benthic photosynthetic dinoflagellates that are phylogenetically separated into four clades based on SSU rDNA molecular phylogeny. This is the first report of this chlorophyll derivative in photosynthetic organisms and we suggest that the derivative is used to quench excess light energy.
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Affiliation(s)
- Norico Yamada
- Department of Natural History Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Ayumi Tanaka
- Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan
| | - Takeo Horiguchi
- Department of Natural History Sciences, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
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31
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McGinley MP, Suggett DJ, Warner ME. Transcript patterns of chloroplast-encoded genes in cultured Symbiodinium spp. (Dinophyceae): testing the influence of a light shift and diel periodicity. JOURNAL OF PHYCOLOGY 2013; 49:709-718. [PMID: 27007203 DOI: 10.1111/jpy.12079] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 04/21/2013] [Indexed: 06/05/2023]
Abstract
Microalgae possess numerous cellular mechanisms specifically employed for acclimating the photosynthetic pathways to changes in the physical environment. Despite the importance of coral-dinoflagellate symbioses, little focus has been given as to how the symbiotic algae (Symbiodinium spp.) regulate the expression of their photosynthetic genes. This study used real-time PCR to investigate the transcript abundance of the plastid-encoded genes, psbA (encoding the D1 protein of photosystem II) and psaA (encoding the P700 protein in photosystem I), within the cultured Symbiodinium ITS-2 (internal transcribed spacer region) types A20 and A13. Transcript abundance was monitored during a low to high-light shift, as well as over a full diel light cycle. In addition, psaA was characterized in three isolates (A20, A13, and D4-5) and noted as another example of a dinoflagellate plastid gene encoded on a minicircle. In general, the overall incongruence of transcript patterns for both psbA and psaA between the Symbiodinium isolates and other models of transcriptionally controlled chloroplast gene expression (e.g., Pisum sativum [pea], Sinapis alba [mustard seedling], and Synechocystis sp. PCC 6803 [cyanobacteria]) suggests that Symbiodinium is reliant on posttranscriptional mechanisms for homeostatic regulation of its photosynthetic proteins.
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Affiliation(s)
- Michael P McGinley
- College of Earth, Ocean, and Environment, University of Delaware, Lewes, Deleware 19958, USA
| | - David J Suggett
- Department of Biological Sciences, University of Essex, Colchester CO4 3SQ, UK
| | - Mark E Warner
- College of Earth, Ocean, and Environment, University of Delaware, Lewes, Deleware 19958, USA
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