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Furukawa M, Kitanobo S, Ohki S, Teramoto MM, Hanahara N, Morita M. Integrative taxonomic analyses reveal that rapid genetic divergence drives Acropora speciation. Mol Phylogenet Evol 2024; 195:108063. [PMID: 38493988 DOI: 10.1016/j.ympev.2024.108063] [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: 11/20/2023] [Revised: 03/11/2024] [Accepted: 03/13/2024] [Indexed: 03/19/2024]
Abstract
Reef-building corals provide the structural basis for one of Earth's most spectacular and diverse but increasingly threatened ecosystems. The reef-building coral genus Acropora may have undergone substantial speciation during the Pleistocene climate and sea-level changes. Here, we aimed to evaluate the speciation history of four morphologically similar tabular Acropora species (Acropora aff. hyacinthus, A. cf. bifurcata, A. cf. cytherea, and A. cf. subulata) using an integrative approach with morphology, genetic, and reproduction methodology. Extensive morphological analyses showed that these four species are distinct and exhibited high gamete incompatibility, preventing hybridization. Furthermore, population structure and principal component analyses with SNPs (>60,000) indicated that these species were genetically distinct, and the ABBA-BABA test did not support introgression among these species. Many of their coding and noncoding RNA sequences showed high genetic variance at loci with high Fst values along the genome. Comparison of these orthologs with those of other Acropora species suggested that many of these genes are under positive selection, which could be associated with spawning time, gamete, and morphological divergence. Our findings show that the speciation of tabular Acropora occurred without hybridization, and the divergence accompanying the rapid evolution of genes in species-rich Acropora could be associated with speciation.
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Affiliation(s)
- Mao Furukawa
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Sesoko, Motobu, Okinawa 905-0227, Japan
| | - Seiya Kitanobo
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka 415-0025, Japan
| | - Shun Ohki
- Department of Immunology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Mariko M Teramoto
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Sesoko, Motobu, Okinawa 905-0227, Japan
| | - Nozomi Hanahara
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Sesoko, Motobu, Okinawa 905-0227, Japan; Okinawa Churashima Foundation Research Center, 888 Ishikawa, Motobu, Okinawa 905-0206, Japan
| | - Masaya Morita
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Sesoko, Motobu, Okinawa 905-0227, Japan.
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Lilly E, Muscala M, Sharkey CR, McCulloch KJ. Larval swimming in the sea anemone Nematostella vectensis is sensitive to a broad light spectrum and exhibits a wavelength-dependent behavioral switch. Ecol Evol 2024; 14:e11222. [PMID: 38628921 PMCID: PMC11019245 DOI: 10.1002/ece3.11222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 03/07/2024] [Accepted: 03/18/2024] [Indexed: 04/19/2024] Open
Abstract
In nearly all animals, light-sensing mediated by opsin visual pigments is important for survival and reproduction. Eyeless light-sensing systems, though vital for many animals, have received relatively less attention than forms with charismatic or complex eyes. Despite no single light-sensing organ, the sea anemone Nematostella vectensis has 29 opsin genes and multiple light-mediated behaviors throughout development and reproduction, suggesting a deceptively complex light-sensing system. To characterize one aspect of this light-sensing system, we analyzed larval swimming behavior at high wavelength resolution across the ultraviolet and visual spectrum. N. vectensis larvae respond to light at least from 315 to 650 nm, which is a broad sensitivity range even compared to many animals with complex eyes. Planktonic swimming is induced by ultraviolet (UV) and violet wavelengths until 420 nm. Between 420 and 430 nm a behavioral switch occurs where at wavelengths longer than 430 nm, larvae respond to light by swimming down. Swimming down toward the substrate is distinct from light avoidance, as animals do not exhibit positive or negative phototaxis at any wavelength tested. At wavelengths longer than 575 nm, animals in the water column take increasingly longer to respond and this behavior is more variable until 650 nm where larval response is no different from the dark, suggesting these longer wavelengths lie outside of their sensitivity range. Larval swimming is the only motile stage in the life history of N. vectensis, and increased planktonic swimming could lead to greater dispersal range in potentially damaging shallow environments with short-wavelength light exposure. Longer wavelength environments may indicate more suitable substrates for metamorphosis into the polyp stage, where the individual will remain for the rest of its life. Future work will test whether this robust behavior is mediated by multiple opsins.
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Affiliation(s)
- Emma Lilly
- Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSt. PaulMinnesotaUSA
| | - Meghan Muscala
- Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSt. PaulMinnesotaUSA
| | - Camilla R. Sharkey
- Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSt. PaulMinnesotaUSA
| | - Kyle J. McCulloch
- Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSt. PaulMinnesotaUSA
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Souto-Neto JA, David DD, Zanetti G, Sua-Cespedes C, Freret-Meurer NV, Moraes MN, de Assis LVM, Castrucci AMDL. Light-specific wavelengths differentially affect the exploration rate, opercular beat, skin color change, opsin transcripts, and the oxi-redox system of the longsnout seahorse Hippocampus reidi. Comp Biochem Physiol A Mol Integr Physiol 2024; 288:111551. [PMID: 37972916 DOI: 10.1016/j.cbpa.2023.111551] [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: 08/31/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 11/19/2023]
Abstract
Light is a strong stimulus for the sensory and endocrine systems. The opsins constitute a large family of proteins that can respond to specific light wavelengths. Hippocampus reidi is a near-threatened seahorse that has a diverse color pattern and sexual dimorphism. Over the years, H. reidi's unique characteristics, coupled with its high demand and over-exploitation for the aquarium trade, have raised concerns about its conservation, primarily due to their significant impact on wild populations. Here, we characterized chromatophore types in juvenile and adult H. reidi in captivity, and the effects of specific light wavelengths with the same irradiance (1.20 mW/cm2) on color change, growth, and survival rate. The xanthophores and melanophores were the major components of H. reidi pigmentation with differences in density and distribution between life stages and sexes. In the eye and skin of juveniles, the yellow (585 nm) wavelength induced a substantial increase in melanin levels compared to the individuals kept under white light (WL), blue (442 nm), or red (650 nm) wavelengths. In addition, blue and yellow wavelengths led to a higher juvenile mortality rate in comparison to the other treatments. Adult seahorses showed a rhythmic color change over 24 h, the highest reflectance values were obtained in the light phase, representing a daytime skin lightening for individuals under WL, blue and yellow wavelength, with changes in the acrophase. The yellow wavelength was more effective on juvenile seahorse pigmentation, while the blue wavelength exerted a stronger effect on the regulation of adult physiological color change. Dramatic changes in the opsin mRNA levels were life stage-dependent, which may infer ontogenetic opsin functions throughout seahorses' development. Exposure to specific wavelengths differentially affected the opsins mRNA levels in the skin and eyes of juveniles. In the juveniles, skin transcripts of visual (rh1, rh2, and lws) and non-visual opsins (opn3 and opn4x) were higher in individuals under yellow light. While in the juvenile's eyes, only rh1 and rh2 had increased transcripts influenced by yellow light; the lws and opn3 mRNA levels were higher in juveniles' eyes under WL. Prolonged exposure to yellow wavelength stimulates a robust increase in the antioxidant enzymes sod1 and sod2 mRNA levels. Our findings indicate that changes in the visible light spectrum alter physiological processes at different stages of life in H. reidi and may serve as the basis for a broader discussion about the implications of artificial light for aquatic species in captivity.
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Affiliation(s)
- José Araújo Souto-Neto
- Laboratory of Comparative Physiology of Pigmentation, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil; Laboratory of Micropollutants, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Daniela Dantas David
- Laboratory of Comparative Physiology of Pigmentation, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Giovanna Zanetti
- Laboratory of Comparative Physiology of Pigmentation, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Cristhian Sua-Cespedes
- Laboratory of Comparative Physiology of Pigmentation, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | | | - Maria Nathália Moraes
- Laboratory of Molecular Chronobiology, Institute of Environmental, Chemical and Pharmaceutical Sciences, Federal University of São Paulo, São Paulo, Brazil
| | | | - Ana Maria de Lauro Castrucci
- Laboratory of Comparative Physiology of Pigmentation, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil; Department of Biology, University of Virginia, Charlottesville, United States.
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Botté A, Payton L, Lefeuvre E, Tran D. Is part-night lighting a suitable mitigation strategy to limit Artificial Light at Night effects on the biological rhythm at the behavioral and molecular scales of the oyster Crassostrea gigas? THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167052. [PMID: 37714354 DOI: 10.1016/j.scitotenv.2023.167052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 09/01/2023] [Accepted: 09/11/2023] [Indexed: 09/17/2023]
Abstract
Artificial Light at Night (ALAN) is a fast-spreading threat to organisms, especially in coastal environments, where night lighting is increasing due to constant anthropization. Considering that ALAN affects a large diversity of coastal organisms, finding efficient solutions to limit these effects is of great importance but poorly investigated. The potential benefit of one strategy, in particular, should be studied since its use is growing: part-night lighting (PNL), which consists in switching off the lights for a few hours during nighttime. The aim of this study is to investigate the positive potential of the PNL strategy on the daily rhythm of the oyster Crassostrea gigas, a key species of coastal areas of ecological and commercial interest. Oysters were exposed to a control condition and three different ALAN modalities. A realistic PNL condition is applied, recreating a strategy of city policy in a coastal city boarding an urbanized bay (Lanton, Arcachon Bay, France). The PNL modality consists in switching off ALAN direct sources (5 lx) for 4 h (23-3 h) during which oysters are in darkness. Then, a PNL + skyglow (PNL + S) modality reproduces the previous one mimicking a skyglow (0.1 lx), an indirect ALAN source, during the direct lighting switch off, to get as close as possible to realistic conditions. Finally, the third ALAN condition mimics full-night direct lighting (FNL). Results revealed that PNL reduces some adverse effects of FNL on the behavioral daily rhythm. But, counterintuitively, PNL + S appears more harmful than FNL for some parameters of the behavioral daily rhythm. PNL + S modality is also the only one that affect oysters' clock and melatonin synthesis gene expression, suggesting physiological consequences. Thus, in realistic conditions, the PNL mitigation strategy might not be beneficial in the presence of skyglow, seeing worse for a coastal organism such as the oysters.
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Affiliation(s)
- Audrey Botté
- Univ. Bordeaux, CNRS, Bordeaux INP, EPOC, UMR 5805, F-33120 Arcachon, France
| | - Laura Payton
- Univ. Bordeaux, CNRS, Bordeaux INP, EPOC, UMR 5805, F-33120 Arcachon, France
| | - Elisa Lefeuvre
- Univ. Bordeaux, CNRS, Bordeaux INP, EPOC, UMR 5805, F-33120 Arcachon, France
| | - Damien Tran
- Univ. Bordeaux, CNRS, Bordeaux INP, EPOC, UMR 5805, F-33120 Arcachon, France.
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5
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Botte A, Payton L, Tran D. The effects of artificial light at night on behavioral rhythm and related gene expression are wavelength dependent in the oyster Crassostrea gigas. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:120375-120386. [PMID: 37938485 DOI: 10.1007/s11356-023-30793-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 10/27/2023] [Indexed: 11/09/2023]
Abstract
Artificial light at night (ALAN) constitutes a growing threat to coastal ecosystems by altering natural light cycles, which could impair organisms' biological rhythms, with resulting physiological and ecological consequences. Coastal ecosystems are strongly exposed to ALAN, but its effects on coastal organisms are poorly studied. Besides ALAN's intensity, ALAN's quality exposure may change the impacts on organisms. This study aims to characterize the effects of different ALAN's spectral compositions (monochromatic wavelength lights in red (peak at 626 nm), green (peak at 515 nm), blue (peak at 467 nm), and white (410-680 nm) light) at low and realistic intensity (1 lx) on the oyster Crassostrea gigas daily rhythm. Results reveal that all ALAN's treatments affect the oysters' daily valve activity rhythm in different manners and the overall expression of the 13 studied genes. Eight of these genes are involved in the oyster's circadian clock, 2 are clock-associated genes, and 3 are light perception genes. The blue light has the most important effects on oysters' valve behavior and clock and clock-associated gene expression. Interestingly, red and green lights also show significant impacts on the daily rhythm, while the lowest impacts are shown with the green light. Finally, ALAN white light shows the same impact as the blue one in terms of loss of rhythmic oysters' percentage, but the chronobiological parameters of the remaining rhythmic oysters are less disrupted than when exposed to each of the monochromatic light's treatments alone. We conclude that ALAN's spectral composition does influence its effect on oysters' daily rhythm, which could give clues to limit physiological and ecological impacts on coastal environments.
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Affiliation(s)
- Audrey Botte
- University of Bordeaux, CNRS, Bordeaux INP, EPOC, UMR 5805, 33120, Arcachon, France
| | - Laura Payton
- University of Bordeaux, CNRS, Bordeaux INP, EPOC, UMR 5805, 33120, Arcachon, France
| | - Damien Tran
- University of Bordeaux, CNRS, Bordeaux INP, EPOC, UMR 5805, 33120, Arcachon, France.
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Monfared MA, Sheridan K, Dixon SP, Gledhill M, Le Berre T. Coral spawning patterns of Acropora across two Maldivian reef ecosystems. PeerJ 2023; 11:e16315. [PMID: 37927798 PMCID: PMC10621594 DOI: 10.7717/peerj.16315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 09/28/2023] [Indexed: 11/07/2023] Open
Abstract
Understanding patterns in coral reproductive biology at local and regional scales is crucial to elucidate our knowledge of characteristics that regulate populations and communities. The lack of published data on coral spawning patterns in the Maldives hinders our understanding of coral reproductive biology and limits our ability to assess shifts in reproductive phenology over time. Here we document baseline environmental cues, spawning patterns, exact timings and oocyte development of restored and wild Acropora, inhabiting shallow water reefs, across two Maldivian atolls. A total of 1,200 colonies were recorded spawning across the two sites between October 2021 and April 2023. These colonies represent 22 species of Acropora, with coral spawning observed over an extended period of eight months. This research details exact spawning times of multi-specific spawning, asynchronous spawning and 'split spawning' of Acropora, across multiple lunar phases; and highlights the need to consider restored colonies when discussing the sexual reproductive patterns of Maldivian Acropora in the future. Overall, corals spawned earlier in North Male Atoll compared with Baa Atoll. Earlier spawning events were significantly correlated with lower tide depths, wind speeds, daily precipitation and higher sea surface temperatures which helped explain inter-atoll, inter-annual, and intra-annual variations in spawning day. This study contributes to understanding sexual reproductive cycles of Acropora in the Maldives; knowledge that is vital for effective management of a critically endangered ecosystem in a changing climate.
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McCulloch KJ, Babonis LS, Liu A, Daly CM, Martindale MQ, Koenig KM. Nematostella vectensis exemplifies the exceptional expansion and diversity of opsins in the eyeless Hexacorallia. EvoDevo 2023; 14:14. [PMID: 37735470 PMCID: PMC10512536 DOI: 10.1186/s13227-023-00218-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 09/11/2023] [Indexed: 09/23/2023] Open
Abstract
BACKGROUND Opsins are the primary proteins responsible for light detection in animals. Cnidarians (jellyfish, sea anemones, corals) have diverse visual systems that have evolved in parallel with bilaterians (squid, flies, fish) for hundreds of millions of years. Medusozoans (e.g., jellyfish, hydroids) have evolved eyes multiple times, each time independently incorporating distinct opsin orthologs. Anthozoans (e.g., corals, sea anemones,) have diverse light-mediated behaviors and, despite being eyeless, exhibit more extensive opsin duplications than medusozoans. To better understand the evolution of photosensitivity in animals without eyes, we increased anthozoan representation in the phylogeny of animal opsins and investigated the large but poorly characterized opsin family in the sea anemone Nematostella vectensis. RESULTS We analyzed genomic and transcriptomic data from 16 species of cnidarians to generate a large opsin phylogeny (708 sequences) with the largest sampling of anthozoan sequences to date. We identified 29 opsins from N. vectensis (NvOpsins) with high confidence, using transcriptomic and genomic datasets. We found that lineage-specific opsin duplications are common across Cnidaria, with anthozoan lineages exhibiting among the highest numbers of opsins in animals. To establish putative photosensory function of NvOpsins, we identified canonically conserved protein domains and amino acid sequences essential for opsin function in other animal species. We show high sequence diversity among NvOpsins at sites important for photoreception and transduction, suggesting potentially diverse functions. We further examined the spatiotemporal expression of NvOpsins and found both dynamic expression of opsins during embryonic development and sexually dimorphic opsin expression in adults. CONCLUSIONS These data show that lineage-specific duplication and divergence has led to expansive diversity of opsins in eyeless cnidarians, suggesting opsins from these animals may exhibit novel biochemical functions. The variable expression patterns of opsins in N. vectensis suggest opsin gene duplications allowed for a radiation of unique sensory cell types with tissue- and stage-specific functions. This diffuse network of distinct sensory cell types could be an adaptive solution for varied sensory tasks experienced in distinct life history stages in Anthozoans.
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Affiliation(s)
- Kyle J McCulloch
- Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN, 55108, USA
| | - Leslie S Babonis
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA
- Whitney Lab for Marine Bioscience, University of Florida, St. Augustine, FL, 32080, USA
| | - Alicia Liu
- John Harvard Distinguished Science Fellowship Program, Harvard University, Cambridge, MA , 02138, , USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Christina M Daly
- John Harvard Distinguished Science Fellowship Program, Harvard University, Cambridge, MA , 02138, , USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Mark Q Martindale
- Whitney Lab for Marine Bioscience, University of Florida, St. Augustine, FL, 32080, USA
| | - Kristen M Koenig
- John Harvard Distinguished Science Fellowship Program, Harvard University, Cambridge, MA , 02138, , USA.
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA.
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX, 78712, USA.
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Kramer N, Tamir R, Galindo-Martínez CT, Wangpraseurt D, Loya Y. Light pollution alters the skeletal morphology of coral juveniles and impairs their light capture capacity. MARINE POLLUTION BULLETIN 2023; 193:115212. [PMID: 37385181 DOI: 10.1016/j.marpolbul.2023.115212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/13/2023] [Accepted: 06/21/2023] [Indexed: 07/01/2023]
Abstract
Urbanization and infrastructure development have changed the night-time light regime of many coastal marine habitats. Consequently, Artificial Light at Night (ALAN) is becoming a global ecological concern, particularly in nearshore coral reef ecosystems. However, the effects of ALAN on coral architecture and their optical properties are unexplored. Here, we conducted a long-term ex situ experiment (30 months from settlement) on juvenile Stylophora pistillata corals grown under ALAN conditions using light-emitting diodes (LEDs) and fluorescent lamps, mimicking light-polluted habitats. We found that corals exposed to ALAN exhibited altered skeletal morphology that subsequently resulted in reduced light capture capacity, while also gaining better structural and optical modifications to increased light levels than their ambient-light counterparts. Additionally, light-polluted corals developed a more porous skeleton compared to the control corals. We suggest that ALAN induces light stress in corals, leading to a decrease in the solar energy available for photosynthesis during daytime illumination.
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Affiliation(s)
- Netanel Kramer
- School of Zoology, Tel-Aviv University, Tel Aviv, Israel; The Steinhardt Museum of Natural History, Israel National Center for Biodiversity Studies, Tel Aviv, Israel.
| | - Raz Tamir
- Israel Oceanography & Limnological Research, National Institute of Oceanography, Haifa, Israel
| | | | - Daniel Wangpraseurt
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego,San Diego, USA; Department of Nanoengineering, University of California San Diego, San Diego, USA
| | - Yossi Loya
- School of Zoology, Tel-Aviv University, Tel Aviv, Israel
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Davies TW, Levy O, Tidau S, de Barros Marangoni LF, Wiedenmann J, D'Angelo C, Smyth T. Global disruption of coral broadcast spawning associated with artificial light at night. Nat Commun 2023; 14:2511. [PMID: 37188683 DOI: 10.1038/s41467-023-38070-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 04/13/2023] [Indexed: 05/17/2023] Open
Abstract
Coral broadcast spawning events - in which gametes are released on certain nights predictably in relation to lunar cycles - are critical to the maintenance and recovery of coral reefs following mass mortality. Artificial light at night (ALAN) from coastal and offshore developments threatens coral reef health by masking natural light:dark cycles that synchronize broadcast spawning. Using a recently published atlas of underwater light pollution, we analyze a global dataset of 2135 spawning observations from the 21st century. For the majority of genera, corals exposed to light pollution are spawning between one and three days closer to the full moon compared to those on unlit reefs. ALAN possibly advances the trigger for spawning by creating a perceived period of minimum illuminance between sunset and moonrise on nights following the full moon. Advancing the timing of mass spawning could decrease the probability of gamete fertilization and survival, with clear implications for ecological processes involved in the resilience of reef systems.
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Affiliation(s)
- Thomas W Davies
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon, PL4 8AA, UK.
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 52900, Israel
- Israel The H. Steinitz Marine Biology Laboratory, The Interuniversity Institute for Marine Sciences of Eilat, P.O. Box 469, Eilat, 88103, Israel
| | - Svenja Tidau
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon, PL4 8AA, UK
| | | | - Joerg Wiedenmann
- Coral Reef Laboratory, University of Southampton, European Way, Southampton, SO143ZH, UK
| | - Cecilia D'Angelo
- Coral Reef Laboratory, University of Southampton, European Way, Southampton, SO143ZH, UK
| | - Tim Smyth
- Plymouth Marine Laboratory, Prospect Place, Plymouth, Devon, PL1 3DH, UK
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Komoto H, Lin CH, Nozawa Y, Satake A. An External Coincidence Model for the Lunar Cycle Reveals Circadian Phase-Dependent Moonlight Effects on Coral Spawning. J Biol Rhythms 2023; 38:148-158. [PMID: 36461677 DOI: 10.1177/07487304221135916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Many marine organisms synchronously spawn at specific times to ensure the success of external fertilization in the ocean. Corals are famous examples of synchronized spawning at specific lunar phases, and two distinct spawning patterns have been observed in two dominant taxa: merulinid corals spawn at regular lunar phases, several days after the full moon, whereas Acropora corals spawn at more irregular lunar phases around the full moon. Although it has been suggested that the two coral taxa have different responses to moonlight and seawater temperature, their spawning times have never been analyzed by integrating the two environmental factors, resulting in an incomplete understanding of the regulatory mechanisms of spawning. In this study, we developed a new predictive model of coral spawning days by integrating moonlight and temperature effects based on the external coincidence model for the lunar cycle. We performed model fitting using a 10-year monitoring record of coral spawning time in Taiwan. Our model successfully demonstrated the synergistic effects of moonlight and temperature on coral spawning time (days) and provided two testable hypotheses to explain the different spawning patterns regarding the preparation (maturation) process for spawning and the sensitivity to moonlight at different circadian phases: (1) Acropora corals may have an earlier onset and longer period of preparation for spawning than merulinid corals; and (2) merulinid corals may use moonlight signals near sunset, while Acropora corals may have a similar onset at approximately midnight. This is the first study to indicate the difference in circadian phase-dependent moonlight sensitivities between coral taxa, providing a basis for underlying coral spawning mechanisms for rhythmic studies.
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Affiliation(s)
- Hideyuki Komoto
- Graduate School of Systems Life Science, Kyushu University, Fukuoka, Japan
| | - Che-Hung Lin
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
- Tropical Biosphere Research Center, University of Ryukyus, Okinawa, Japan
| | - Yoko Nozawa
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Akiko Satake
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka, Japan
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Kim HJ, Kim NN, Han J, Park HS, Kang DH, Choi YU. Reproductive condition of the black-lip pearl oyster Pinctada margaritifera during the lunar phase. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2023; 339:302-309. [PMID: 36650734 DOI: 10.1002/jez.2679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 01/19/2023]
Abstract
This study analyzed the relationship between the lunar phase and the reproductive cycle of Pinctada margaritifera inhabiting Weno Island, Chuuk Lagoon, Micronesia. We measured indicators of maturity (gonadosomatic index [GSI] and sexual maturation-related genes) and investigated changes in the gonadal maturity stages (GMS) of P. margaritifera over lunar cycle. GSI was higher around the full moon. GMS of P. margaritifera were classified as the early gametogenesis stage, ripe and spawning stage, and spent and degenerating stage. A large percentage of oysters was observed in the ripe and spawning stage at the first quarter moon in female and the full moon in male as well as in the spent and degenerating stages at the third quarter moon in both sexes. In addition, the expression of doublesex- and mab-3-related transcription factor 2 (DMRT2) in the male P. margaritifera black-lip pearl oyster was the highest during the full and third quarter moon phases, whereas no difference in expression was observed with the lunar phase in females. In contrast, the expression of vitellogenin (VTG) was the highest in female P. margaritifera during the first and third quarters. No difference in expression was observed according to the lunar phase in males. The results suggest that the lunar phase directly affects the expression of sexually mature gonads in P. margaritifera black-lip pearl oyster.
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Affiliation(s)
- Han-Jun Kim
- Marine Bio-Resources Research Unit, Korea Institute of Ocean Science & Technology (KIOST), Busan, Republic of Korea
| | - Na Na Kim
- National Institute of Fisheries Science, Changwon, Republic of Korea
| | - Jeonghoon Han
- Marine Bio-Resources Research Unit, Korea Institute of Ocean Science & Technology (KIOST), Busan, Republic of Korea
| | - Heung-Sik Park
- Research Project Development, Korea Institute of Ocean & Technology (KIOST), Busan, Republic of Korea
| | - Do-Hyung Kang
- Jeju Marine Research Center, Korea Institute of Ocean & Technology (KIOST), Jeju, Korea
| | - Young-Ung Choi
- Marine Bio-Resources Research Unit, Korea Institute of Ocean Science & Technology (KIOST), Busan, Republic of Korea
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12
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Mason BM, Koyanagi M, Sugihara T, Iwasaki M, Slepak V, Miller DJ, Sakai Y, Terakita A. Multiple opsins in a reef-building coral, Acropora millepora. Sci Rep 2023; 13:1628. [PMID: 36710295 PMCID: PMC9884665 DOI: 10.1038/s41598-023-28476-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 01/19/2023] [Indexed: 01/30/2023] Open
Abstract
Opsins, light-sensitive G protein-coupled receptors, have been identified in corals but their properties are largely unknown. Here, we identified six opsin genes (acropsins 1-6) from a coral species Acropora millepora, including three novel opsins (acropsins 4-6), and successfully characterized the properties of four out of the six acropsins. Acropsins 1 and 6 exhibited light-dependent cAMP increases in cultured cells, suggesting that the acropsins could light-dependently activate Gs-type G protein like the box jellyfish opsin from the same opsin group. Spectral sensitivity curves having the maximum sensitivities at ~ 472 nm and ~ 476 nm were estimated for acropsins 1 and 6, respectively, based on the light wavelength-dependent cAMP increases in these opsins-expressing cells (heterologous action spectroscopy). Acropsin 2 belonging to the same group as acropsins 1 and 6 did not induce light-dependent cAMP or Ca2+ changes. We then successfully estimated the acropsin 2 spectral sensitivity curve having its maximum value at ~ 471 nm with its chimera mutant which possessed the third cytoplasmic loop of the Gs-coupled jellyfish opsin. Acropsin 4 categorized as another group light-dependently induced intracellular Ca2+ increases but not cAMP changes. Our results uncovered that the Acropora coral possesses multiple opsins coupling two distinct cascades, cyclic nucleotide and Ca2+signaling light-dependently.
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Affiliation(s)
- Benjamin M Mason
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, 4811, Australia.,Molecular and Cell Biology, James Cook University, Townsville, QLD, 4811, Australia
| | - Mitsumasa Koyanagi
- Department of Biology and Geosciences, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan.,The OCU Advanced Research Institute for Natural Science and Technology, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan.,Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan
| | - Tomohiro Sugihara
- Department of Biology and Geosciences, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan.,Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan
| | - Makoto Iwasaki
- Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan
| | - Vladlen Slepak
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - David J Miller
- Centre for Tropical Bioinformatics and Molecular Biology, James Cook University, Townsville, QLD, Australia.,Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Yusuke Sakai
- Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan
| | - Akihisa Terakita
- Department of Biology and Geosciences, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan. .,The OCU Advanced Research Institute for Natural Science and Technology, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan. .,Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan.
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13
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Solar radiation, temperature and the reproductive biology of the coral Lobactis scutaria in a changing climate. Sci Rep 2023; 13:246. [PMID: 36604569 PMCID: PMC9816315 DOI: 10.1038/s41598-022-27207-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 12/28/2022] [Indexed: 01/07/2023] Open
Abstract
Coral reefs worldwide are at risk due to climate change. Coral bleaching is becoming increasingly common and corals that survive bleaching events can suffer from temporary reproductive failure for several years. While water temperature is a key driver in causing coral bleaching, other environmental factors are involved, such as solar radiation. We investigated the individual and combined effects of temperature, photosynthetically active radiation (PAR), and ultraviolet radiation (UVR) on the spawning patterns and reproductive physiology of the Hawaiian mushroom coral Lobactis scutaria, using long-term experiments in aquaria. We examined effects on spawning timing, fertilisation success, and gamete physiology. Both warmer temperatures and filtering UVR altered the timing of spawning. Warmer temperatures caused a drop in fertilisation success. Warmer temperatures and higher PAR both negatively affected sperm and egg physiology. These results are concerning for the mushroom coral L. scutaria and similar reproductive data are urgently needed to predict future reproductive trends in other species. Nonetheless, thermal stress from global climate change will need to be adequately addressed to ensure the survival of reef-building corals in their natural environment throughout the next century and beyond. Until then, reproduction is likely to be increasingly impaired in a growing number of coral species.
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14
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Wang X, Li Y, Lin M, Su Z, Liu X, Yu K. Variations in the coral community at the high-latitude Bailong Peninsula, northern South China Sea. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:274-286. [PMID: 35900625 DOI: 10.1007/s11356-022-21881-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 07/01/2022] [Indexed: 06/15/2023]
Abstract
High-latitude coral communities have attracted much attention due to their potential as refuges during global climate change. However, this function is being constrained by the combined pressure of global climate and anthropogenic activities. To determine how the reef has developed, we conducted a long-term monitoring study on coral communities along the Bailong Peninsula in the northern South China Sea. The results showed that the distribution area of corals was 3.67 km2 and that corals extended about 4.7 km along the coastline. The coral distribution pattern is scattered and uneven. Our results showed that the growth of reef-building corals and coral recruitment are improving, indicating that coral recruitment plays an important role in regulating the structure of adult coral populations and promoting the development of coral communities. Bailong Peninsula is expected to become a refuge for corals provided that human activities impacting coral restoration potential are controlled.
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Affiliation(s)
- Xin Wang
- School of Marine Sciences, Guangxi University, Nanning, 530004, China
- Guangxi Key Lab of Mangrove Conservation and Utilization, Guangxi Mangrove Research Center of Guangxi Sciences Academy, Beihai, 536000, China
- Forestry College of Guangxi University, Nanning, 530004, China
| | - Yinqiang Li
- School of Marine Sciences, Guangxi University, Nanning, 530004, China
| | - Mingqing Lin
- Guangxi Key Lab of Mangrove Conservation and Utilization, Guangxi Mangrove Research Center of Guangxi Sciences Academy, Beihai, 536000, China
| | - Zhinan Su
- Guangxi Key Lab of Mangrove Conservation and Utilization, Guangxi Mangrove Research Center of Guangxi Sciences Academy, Beihai, 536000, China
| | - Xiong Liu
- Sea Area Use Dynamic Supervision Center, Fangchenggang, 53800, China
| | - Kefu Yu
- School of Marine Sciences, Guangxi University, Nanning, 530004, China.
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15
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Bauer F, Ritter M, Šiljeg A, Gretschel G, Lenz M. Effects of artificial light at night on the feeding behaviour of three marine benthic grazers from the Adriatic Sea are species-specific and mostly short-lived. MARINE POLLUTION BULLETIN 2022; 185:114303. [PMID: 36395715 DOI: 10.1016/j.marpolbul.2022.114303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 10/19/2022] [Accepted: 10/22/2022] [Indexed: 06/16/2023]
Abstract
Artificial light at night (ALAN) has the potential to change the day-night activity of marine benthic grazers, and can therefore alter the top-down control they exert on macroalgal communities. In laboratory experiments, we investigated the influence of three realistic ALAN regimes on food consumption and feeding rhythmicity in the sea urchins Arbacia lixula and Paracentrotus lividus as well as in the snail Cerithium spp. from the Adriatic Sea. Food consumption was assessed in assays with algal pellets, while feeding rhythms were documented with 24 h time-lapse photography. Both was done in ALAN-acclimated and in non-acclimated animals. We observed temporary and potential long-term changes in the feeding rhythms of Cerithium spp. and Paracentrotus lividus, respectively, but found no lasting influence of ALAN on consumption rates. Effects were weaker when ALAN was applied only part-night, which suggests a possible mitigation measure to reduce the impact of nighttime lighting on coastal ecosystems.
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Affiliation(s)
- Franz Bauer
- Marine Ecology Research Division, GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany.
| | - Marie Ritter
- Marine Ecology Research Division, GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
| | - Anamarija Šiljeg
- Department of Biology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, 10000 Zagreb, Croatia
| | - Gerwin Gretschel
- Meeresschule Pula (Morska Škola Valsaline), Marine Education Center, Valsaline 31, 52100 Pula, Croatia
| | - Mark Lenz
- Marine Ecology Research Division, GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
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16
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Fitness consequences of chronic exposure to different light pollution wavelengths in nocturnal and diurnal rodents. Sci Rep 2022; 12:16486. [PMID: 36182961 PMCID: PMC9526750 DOI: 10.1038/s41598-022-19805-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 09/05/2022] [Indexed: 12/05/2022] Open
Abstract
Use of artificial at night (ALAN) exposes the world to continuously increasing levels and distribution of light pollution. Our understanding of the adverse effects of ALAN is based mostly on observational or laboratory studies, and its effects are probably underestimated. Demonstration of direct experimental fitness consequences of ALAN on mammals is missing. We studied the effects of chronic light pollution at different wavelengths on fitness and glucocorticoid hormone levels under semi-natural conditions in two closely related species: the nocturnal common spiny mouse (Acomys cahirinus) and the diurnal golden spiny mouse (Acomys russatus). Our results clearly demonstrate the adverse effects of ALAN exposure on the fitness of both nocturnal and diurnal species, manifested by changes in cortisol levels and reproductive timing, reduced reproductive output and reduced survival, which differed between species and wavelengths. In A. russatus exposure to blue ALAN had the strongest effect on fitness, followed by white and yellow ALAN exposure. In A. cahirinus the results are more complex and suggest it suffered from the combined effects of ALAN and competition. Our research shows that light pollution presents a real threat to both nocturnal and diurnal species, affecting the species fitness directly and through interspecific interactions. Worryingly, these effects are probably not limited to spiny mice. The clear adverse effects we documented, as well as the differences between wave lengths, contribute to our ability to present science-based recommendations to decision makers regarding the use of artificial light at night. Such information and guidelines are highly important nowadays when lighting systems are being replaced to promote energy efficiency.
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17
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Juretić D. Designed Multifunctional Peptides for Intracellular Targets. Antibiotics (Basel) 2022; 11:antibiotics11091196. [PMID: 36139975 PMCID: PMC9495127 DOI: 10.3390/antibiotics11091196] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 08/25/2022] [Accepted: 08/29/2022] [Indexed: 11/25/2022] Open
Abstract
Nature’s way for bioactive peptides is to provide them with several related functions and the ability to cooperate in performing their job. Natural cell-penetrating peptides (CPP), such as penetratins, inspired the design of multifunctional constructs with CPP ability. This review focuses on known and novel peptides that can easily reach intracellular targets with little or no toxicity to mammalian cells. All peptide candidates were evaluated and ranked according to the predictions of low toxicity to mammalian cells and broad-spectrum activity. The final set of the 20 best peptide candidates contains the peptides optimized for cell-penetrating, antimicrobial, anticancer, antiviral, antifungal, and anti-inflammatory activity. Their predicted features are intrinsic disorder and the ability to acquire an amphipathic structure upon contact with membranes or nucleic acids. In conclusion, the review argues for exploring wide-spectrum multifunctionality for novel nontoxic hybrids with cell-penetrating peptides.
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Affiliation(s)
- Davor Juretić
- Mediterranean Institute for Life Sciences, 21000 Split, Croatia;
- Faculty of Science, University of Split, 21000 Split, Croatia;
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18
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Rosenberg Y, Simon‐Blecher N, Lalzar M, Yam R, Shemesh A, Alon S, Perna G, Cárdenas A, Voolstra CR, Miller DJ, Levy O. Urbanization comprehensively impairs biological rhythms in coral holobionts. GLOBAL CHANGE BIOLOGY 2022; 28:3349-3364. [PMID: 35218086 PMCID: PMC9311646 DOI: 10.1111/gcb.16144] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 02/08/2022] [Accepted: 02/09/2022] [Indexed: 05/28/2023]
Abstract
Coral reefs are in global decline due to climate change and anthropogenic influences (Hughes et al., Conservation Biology, 27: 261-269, 2013). Near coastal cities or other densely populated areas, coral reefs face a range of additional challenges. While considerable progress has been made in understanding coral responses to acute individual stressors (Dominoni et al., Nature Ecology & Evolution, 4: 502-511, 2020), the impacts of chronic exposure to varying combinations of sensory pollutants are largely unknown. To investigate the impacts of urban proximity on corals, we conducted a year-long in-natura study-incorporating sampling at diel, monthly, and seasonal time points-in which we compared corals from an urban area to corals from a proximal non-urban area. Here we reveal that despite appearing relatively healthy, natural biorhythms and environmental sensory systems were extensively disturbed in corals from the urban environment. Transcriptomic data indicated poor symbiont performance, disturbance to gametogenic cycles, and loss or shifted seasonality of vital biological processes. Altered seasonality patterns were also observed in the microbiomes of the urban coral population, signifying the impact of urbanization on the holobiont, rather than the coral host alone. These results should raise alarm regarding the largely unknown long-term impacts of sensory pollution on the resilience and survival of coral reefs close to coastal communities.
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Affiliation(s)
- Yaeli Rosenberg
- Mina and Everard Goodman Faculty of Life SciencesBar‐Ilan UniversityRamat GanIsrael
| | - Noa Simon‐Blecher
- Mina and Everard Goodman Faculty of Life SciencesBar‐Ilan UniversityRamat GanIsrael
| | - Maya Lalzar
- Bioinformatics Service UnitUniversity of HaifaHaifaIsrael
| | - Ruth Yam
- Department of Earth and Planetary SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Aldo Shemesh
- Department of Earth and Planetary SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Shahar Alon
- Faculty of EngineeringBar‐Ilan UniversityRamat GanIsrael
| | - Gabriela Perna
- Department of BiologyUniversity of KonstanzKonstanzGermany
| | - Anny Cárdenas
- Department of BiologyUniversity of KonstanzKonstanzGermany
| | | | - David J. Miller
- ARC Centre of Excellence for Coral Reef Studies and School of Pharmacy and Molecular SciencesJames Cook UniversityTownsvilleQueenslandAustralia
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life SciencesBar‐Ilan UniversityRamat GanIsrael
- The H. Steinitz Marine Biology LaboratoryThe Interuniversity Institute for Marine Sciences of EilatEilatIsrael
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19
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Dickerson AL, Hall ML, Jones TM. The effect of natural and artificial light at night on nocturnal song in the diurnal willie wagtail. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 808:151986. [PMID: 34843784 DOI: 10.1016/j.scitotenv.2021.151986] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/22/2021] [Accepted: 11/22/2021] [Indexed: 06/13/2023]
Abstract
Artificial light at night (ALAN) has rapidly and drastically changed the global nocturnal environment. Evidence for the effect of ALAN on animal behaviour is mounting and animals are exposed to both point sources of light (street and other surrounding light sources) and broadscale illuminance in the form of skyglow. Research has typically taken a simplified approach to assessing the presence of ALAN, yet to fully understand the ecological impact requires consideration of the different scales and sources of light concurrently. Bird song has previously been well studied for its relationship with light, offering an opportunity to examine the relative impact of different sources of light on behaviour. In this study, we combine correlational and experimental approaches to examine how light at night affects the nocturnal song behaviour of the largely diurnal willie wagtail (Rhipidura leucophrys). Observations of willie wagtails across urban and rural locations in southeastern Australia demonstrated that nocturnal song behaviour increased with the intensity of moonlight in darker rural areas but decreased in areas with high sky glow. In addition, willie wagtails were half as likely to sing at night in the presence of localized light sources such as streetlights in urban and rural areas. Experimental introduction of streetlights to a previously dark area confirmed this relationship: willie wagtail song rates declined when lights were turned on and returned to their original rates following streetlight removal. Our findings show that scale, as well as intensity, are important when considering the impact of light at night as moonlight, sky glow, and localized sources of artificial light have different effects on nocturnal song behaviour.
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Affiliation(s)
- Ashton L Dickerson
- School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia.
| | - Michelle L Hall
- School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia; Bush Heritage Australia, 395 Collins Street, Melbourne, Vic 3000, Australia; School of Biological Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Therésa M Jones
- School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia
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20
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Molecular mechanisms of sperm motility are conserved in an early-branching metazoan. Proc Natl Acad Sci U S A 2021; 118:2109993118. [PMID: 34810263 PMCID: PMC8640785 DOI: 10.1073/pnas.2109993118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2021] [Indexed: 01/11/2023] Open
Abstract
Reef-building corals are the keystone species of the world’s most biodiverse yet threatened marine ecosystems. Coral reproduction, critical for reef resilience, requires that coral sperm swim through the water column to reach the egg. However, little is known about the mechanisms that regulate coral sperm motility. We found here that coral sperm motility is pH dependent and that activation of motility requires signaling via the pH-sensing enzyme soluble adenylyl cyclase. This study reveals the deep conservation of a sperm activation pathway from humans to corals, presenting the first comprehensive examination of the molecular mechanisms regulating sperm motility in an early-diverging animal. These results are critical for understanding the resilience of this sensitive life stage to a changing marine environment. Efficient and targeted sperm motility is essential for animal reproductive success. Sperm from mammals and echinoderms utilize a highly conserved signaling mechanism in which sperm motility is stimulated by pH-dependent activation of the cAMP-producing enzyme soluble adenylyl cyclase (sAC). However, the presence of this pathway in early-branching metazoans has remained unexplored. Here, we found that elevating cytoplasmic pH induced a rapid burst of cAMP signaling and triggered the onset of motility in sperm from the reef-building coral Montipora capitata in a sAC-dependent manner. Expression of sAC in the mitochondrial-rich midpiece and flagellum of coral sperm support a dual role for this molecular pH sensor in regulating mitochondrial respiration and flagellar beating and thus motility. In addition, we found that additional members of the homologous signaling pathway described in echinoderms, both upstream and downstream of sAC, are expressed in coral sperm. These include the Na+/H+ exchanger SLC9C1, protein kinase A, and the CatSper Ca2+ channel conserved even in mammalian sperm. Indeed, the onset of motility corresponded with increased protein kinase A activity. Our discovery of this pathway in an early-branching metazoan species highlights the ancient origin of the pH-sAC-cAMP signaling node in sperm physiology and suggests that it may be present in many other marine invertebrate taxa for which sperm motility mechanisms remain unexplored. These results emphasize the need to better understand the role of pH-dependent signaling in the reproductive success of marine animals, particularly as climate change stressors continue to alter the physiology of corals and other marine invertebrates.
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21
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Moonrise timing is key for synchronized spawning in coral Dipsastraea speciosa. Proc Natl Acad Sci U S A 2021; 118:2101985118. [PMID: 34373318 DOI: 10.1073/pnas.2101985118] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Synchronized mass coral spawning typically occurs several days after a full moon once a year. It is expected that spawning day is determined by corals sensing environmental change regulated by the lunar cycle (i.e., tide or moonlight); however, the exact regulatory mechanism remains unknown. Here, we demonstrate how moonlight influences the spawning process of coral, Dipsastraea speciosa When corals in the field were shaded 1 and 3 d before the full moon or 1 d after the full moon, spawning always occurred 5 d after shading commenced. These results suggest moonlight suppresses spawning: a hypothesis supported by laboratory experiments in which we monitored the effects of experimental moonlight (night-light) on spawning day. Different night-light treatments in the laboratory showed that the presence of a dark period between day-light and night-light conditions eliminates the suppressive effect of night-light on spawning. In nature, moonrise gets progressively later during the course of the lunar cycle, shifting to after sunset following the day of the full moon. Our results indicate that this period of darkness between sunset and moonrise triggers synchronized mass spawning of D. speciosa in nature.
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22
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Cellular pathways during spawning induction in the starlet sea anemone Nematostella vectensis. Sci Rep 2021; 11:15451. [PMID: 34326433 PMCID: PMC8322078 DOI: 10.1038/s41598-021-95033-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 07/13/2021] [Indexed: 12/12/2022] Open
Abstract
In cnidarians, long-term ecological success relies on sexual reproduction. The sea anemone Nematostella vectensis, which has emerged as an important model organism for developmental studies, can be induced for spawning by temperature elevation and light exposure. To uncover molecular mechanisms and pathways underlying spawning, we characterized the transcriptome of Nematostella females before and during spawning induction. We identified an array of processes involving numerous receptors, circadian clock components, cytoskeleton, and extracellular transcripts that are upregulated upon spawning induction. Concurrently, processes related to the cell cycle, fatty acid metabolism, and other housekeeping functions are downregulated. Real-time qPCR revealed that light exposure has a minor effect on expression levels of most examined transcripts, implying that temperature change is a stronger inducer for spawning in Nematostella. Our findings reveal the potential mechanisms that may enable the mesenteries to serve as a gonad-like tissue for the developing oocytes and expand our understanding of sexual reproduction in cnidarians.
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23
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Gornik SG, Bergheim BG, Morel B, Stamatakis A, Foulkes NS, Guse A. Photoreceptor Diversification Accompanies the Evolution of Anthozoa. Mol Biol Evol 2021; 38:1744-1760. [PMID: 33226083 PMCID: PMC8097283 DOI: 10.1093/molbev/msaa304] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Anthozoan corals are an ecologically important group of cnidarians, which power the productivity of reef ecosystems. They are sessile, inhabit shallow, tropical oceans and are highly dependent on sun- and moonlight to regulate sexual reproduction, phototaxis, and photosymbiosis. However, their exposure to high levels of sunlight also imposes an increased risk of UV-induced DNA damage. How have these challenging photic environments influenced photoreceptor evolution and function in these animals? To address this question, we initially screened the cnidarian photoreceptor repertoire for Anthozoa-specific signatures by a broad-scale evolutionary analysis. We compared transcriptomic data of more than 36 cnidarian species and revealed a more diverse photoreceptor repertoire in the anthozoan subphylum than in the subphylum Medusozoa. We classified the three principle opsin classes into distinct subtypes and showed that Anthozoa retained all three classes, which diversified into at least six subtypes. In contrast, in Medusozoa, only one class with a single subtype persists. Similarly, in Anthozoa, we documented three photolyase classes and two cryptochrome (CRY) classes, whereas CRYs are entirely absent in Medusozoa. Interestingly, we also identified one anthozoan CRY class, which exhibited unique tandem duplications of the core functional domains. We next explored the functionality of anthozoan photoreceptors in the model species Exaiptasia diaphana (Aiptasia), which recapitulates key photo-behaviors of corals. We show that the diverse opsin genes are differentially expressed in important life stages common to reef-building corals and Aiptasia and that CRY expression is light regulated. We thereby provide important clues linking coral evolution with photoreceptor diversification.
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Affiliation(s)
- Sebastian G Gornik
- Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany
| | | | - Benoit Morel
- Computational Molecular Evolution Group, Heidelberg Institute for Theoretical Studies, Heidelberg, Germany
| | - Alexandros Stamatakis
- Computational Molecular Evolution Group, Heidelberg Institute for Theoretical Studies, Heidelberg, Germany.,Institute for Theoretical Informatics, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Nicholas S Foulkes
- Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.,Institute of Biological and Chemical Systems, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Annika Guse
- Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany
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24
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Tidau S, Smyth T, McKee D, Wiedenmann J, D’Angelo C, Wilcockson D, Ellison A, Grimmer AJ, Jenkins SR, Widdicombe S, Queirós AM, Talbot E, Wright A, Davies TW. Marine artificial light at night: An empirical and technical guide. Methods Ecol Evol 2021. [DOI: 10.1111/2041-210x.13653] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Svenja Tidau
- School of Biological and Marine Sciences University of Plymouth Plymouth UK
- School of Ocean Sciences Bangor University Menai Bridge UK
| | - Tim Smyth
- Plymouth Marine Laboratory Plymouth UK
| | - David McKee
- Physics Department University of Strathclyde Glasgow UK
- Department of Arctic and Marine Biology UiT The Arctic University of Norway Tromsø Norway
| | - Jörg Wiedenmann
- School of Ocean and Earth Science University of Southampton Southampton UK
| | - Cecilia D’Angelo
- School of Ocean and Earth Science University of Southampton Southampton UK
| | - David Wilcockson
- Institute of Biological Environmental & Rural Sciences Aberystwyth University Aberystwyth UK
| | - Amy Ellison
- School of Natural Sciences Bangor University Bangor UK
| | - Andrew J. Grimmer
- School of Biological and Marine Sciences University of Plymouth Plymouth UK
| | | | | | | | | | | | - Thomas W. Davies
- School of Biological and Marine Sciences University of Plymouth Plymouth UK
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Ayalon I, Benichou JIC, Avisar D, Levy O. The Endosymbiotic Coral Algae Symbiodiniaceae Are Sensitive to a Sensory Pollutant: Artificial Light at Night, ALAN. Front Physiol 2021; 12:695083. [PMID: 34234696 PMCID: PMC8256845 DOI: 10.3389/fphys.2021.695083] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 05/24/2021] [Indexed: 11/13/2022] Open
Abstract
Artificial Light at Night, ALAN, is a major emerging issue in biodiversity conservation, which can negatively impact both terrestrial and marine environments. Therefore, it should be taken into serious consideration in strategic planning for urban development. While the lion's share of research has dealt with terrestrial organisms, only a handful of studies have focused on the marine milieu. To determine if ALAN impacts the coral reef symbiotic algae, that are fundamental for sustainable coral reefs, we conducted a short experiment over a period of one-month by illuminating isolated Symbiodiniaceae cell cultures from the genera Cladocopium (formerly Clade C) and Durusdinium (formerly Clade D) with LED light. Cell cultures were exposed nightly to ALAN levels of 0.15 μmol quanta m-2 s-1 (∼4-5 lux) with three light spectra: blue, yellow and white. Our findings showed that even in very low levels of light at night, the photo-physiology of the algae's Electron Transport Rate (ETR), Non-Photochemical Quenching, (NPQ), total chlorophyll, and meiotic index presented significantly lower values under ALAN, primarily, but not exclusively, in Cladocopium cell cultures. The findings also showed that diverse Symbiodiniaceae types have different photo-physiology and photosynthesis performances under ALAN. We believe that our results sound an alarm for the probable detrimental effects of an increasing sensory pollutant, ALAN, on the eco-physiology of symbiotic corals. The results of this study point to the potential effects of ALAN on other organisms in marine ecosystem such as fish, zooplankton, and phytoplankton in which their biorhythms is entrained by natural light and dark cycles.
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Affiliation(s)
- Inbal Ayalon
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel.,Israel The H. Steinitz Marine Biology Laboratory, The Interuniversity Institute for Marine Sciences of Eilat, Eilat, Israel.,Faculty of Exact Sciences, Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Jennifer I C Benichou
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Dror Avisar
- Faculty of Exact Sciences, Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel.,Israel The H. Steinitz Marine Biology Laboratory, The Interuniversity Institute for Marine Sciences of Eilat, Eilat, Israel
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Kaiser TS, Neumann J. Circalunar clocks-Old experiments for a new era. Bioessays 2021; 43:e2100074. [PMID: 34050958 DOI: 10.1002/bies.202100074] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/28/2021] [Accepted: 05/03/2021] [Indexed: 12/23/2022]
Abstract
Circalunar clocks, which allow organisms to time reproduction to lunar phase, have been experimentally proven but are still not understood at the molecular level. Currently, a new generation of researchers with new tools is setting out to fill this gap. Our essay provides an overview of classic experiments on circalunar clocks. From the unpublished work of the late D. Neumann we also present a novel phase response curve for a circalunar clock. These experiments highlight avenues for molecular work and call for rigor in setting up and analyzing the logistically complex experiments on circalunar clocks. Re-evaluating classic experiments, we propose that (1) circalunar clocks in different organisms will have divergent mechanisms and physiological bases, (2) they may have properties very different from the well-studied circadian clocks and (3) they may have close mechanistic and molecular relations to seasonal rhythms and diapause.
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Affiliation(s)
- Tobias S Kaiser
- Max Planck Research Group "Biological Clocks", Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Jule Neumann
- Max Planck Research Group "Biological Clocks", Max Planck Institute for Evolutionary Biology, Plön, Germany
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Morphological stasis masks ecologically divergent coral species on tropical reefs. Curr Biol 2021; 31:2286-2298.e8. [PMID: 33811819 DOI: 10.1016/j.cub.2021.03.028] [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: 11/05/2020] [Revised: 02/13/2021] [Accepted: 03/09/2021] [Indexed: 01/07/2023]
Abstract
Coral reefs are the epitome of species diversity, yet the number of described scleractinian coral species, the framework-builders of coral reefs, remains moderate by comparison. DNA sequencing studies are rapidly challenging this notion by exposing a wealth of undescribed diversity, but the evolutionary and ecological significance of this diversity remains largely unclear. Here, we present an annotated genome for one of the most ubiquitous corals in the Indo-Pacific (Pachyseris speciosa) and uncover, through a comprehensive genomic and phenotypic assessment, that it comprises morphologically indistinguishable but ecologically divergent lineages. Demographic modeling based on whole-genome resequencing indicated that morphological crypsis (across micro- and macromorphological traits) was due to ancient morphological stasis rather than recent divergence. Although the lineages occur sympatrically across shallow and mesophotic habitats, extensive genotyping using a rapid molecular assay revealed differentiation of their ecological distributions. Leveraging "common garden" conditions facilitated by the overlapping distributions, we assessed physiological and quantitative skeletal traits and demonstrated concurrent phenotypic differentiation. Lastly, spawning observations of genotyped colonies highlighted the potential role of temporal reproductive isolation in the limited admixture, with consistent genomic signatures in genes related to morphogenesis and reproduction. Overall, our findings demonstrate the presence of ecologically and phenotypically divergent coral species without substantial morphological differentiation and provide new leads into the potential mechanisms facilitating such divergence. More broadly, they indicate that our current taxonomic framework for reef-building corals may be scratching the surface of the ecologically relevant diversity on coral reefs, consequently limiting our ability to protect or restore this diversity effectively.
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Liberman R, Fine M, Benayahu Y. Simulated climate change scenarios impact the reproduction and early life stages of a soft coral. MARINE ENVIRONMENTAL RESEARCH 2021; 163:105215. [PMID: 33360640 DOI: 10.1016/j.marenvres.2020.105215] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 11/05/2020] [Accepted: 11/15/2020] [Indexed: 05/19/2023]
Abstract
Coral reefs are threatened worldwide by global climate change, manifested in anthropogenic ocean warming and acidification. Despite the importance of coral sexual reproduction for the continuity of coral reefs, our understanding of the extent of the impact of climate change on coral sexual reproduction, particularly on coral reproductive phenology and early life stages, is limited. Here, we experimentally examined the effects of predicted end-of-the-century seawater conditions on the sexual reproduction and photosynthetic capacity of a Red-Sea zooxanthellate octocoral, Rhytisma fulvum. Sexually mature colonies were exposed to ambient temperature and pH conditions and to Representative Concentration Pathway (RCP) conditions (4.5 and 8.5), five weeks prior to their expected surface-brooding event. The reproductive phenology of the colonies under the simulated seawater conditions was compared to that on the natural reef. In addition, subsequent planulae development and their metamorphosis into primary polyps under the same RCP conditions as their parent colonies were monitored in a running seawater system. The results reveal that both RCP conditions led to a change in the timing of onset of the surface-brooding event and its synchronicity. In contrast, the surface-brooding event under ambient conditions co-occurred with that of the in-situ reef colonies and maintained its synchrony. Similarly, planula survival and polyp metamorphosis rate were significantly reduced under both RCP conditions compared to propagules reared under ambient conditions. In addition, the photosynthetic capacity of the parent colonies under both RCPs showed a reduction relative to that under the ambient conditions in the experiment, suggesting a reduction in carbon fixation during the late stages of gametogenesis. While our findings indicate that octocoral reproductive phenology is affected by environmental changes, further work is required in order to elucidate the long-term implications for the R. fulvum population in the northern Red Sea.
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Affiliation(s)
- Ronen Liberman
- School of Zoology, The George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, 69978, Israel; The Interuniversity Institute for Marine Sciences, Eilat, 8810302, Israel.
| | - Maoz Fine
- The Interuniversity Institute for Marine Sciences, Eilat, 8810302, Israel; The Mina and Everard Goodman Faculty of Life Sciences, Bar Ilan University, Ramat Gan, 5290002, Israel
| | - Yehuda Benayahu
- School of Zoology, The George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, 69978, Israel.
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Ayalon I, Rosenberg Y, Benichou JIC, Campos CLD, Sayco SLG, Nada MAL, Baquiran JIP, Ligson CA, Avisar D, Conaco C, Kuechly HU, Kyba CCM, Cabaitan PC, Levy O. Coral Gametogenesis Collapse under Artificial Light Pollution. Curr Biol 2020; 31:413-419.e3. [PMID: 33157030 DOI: 10.1016/j.cub.2020.10.039] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/21/2020] [Accepted: 10/08/2020] [Indexed: 01/10/2023]
Abstract
Artificial light at night (ALAN) can have negative impacts on the health of humans and ecosystems.1-4 Marine organisms, including coral reefs in particular, rely on the natural light cycles of sunlight and moonlight to regulate various physiological, biological, and behavioral processes.5-8 Here, we demonstrate that light pollution caused delayed gametogenesis and unsynchronized gamete release in two coral species, Acropora millepora and Acropora digitifera, from the Indo-Pacific Ocean. Given the urbanization along major coasts, light pollution could thus further threaten coral communities' populations, which are already under severe degradation. A worldwide-modeled light pollution impact assessment is provided, which can help incorporate an important variable in coral reef conservation planning.
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Affiliation(s)
- Inbal Ayalon
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel; The H. Steinitz Marine Biology Laboratory, The Interuniversity Institute for Marine Sciences of Eilat, PO Box 469, Eilat 88103, Israel; Porter School of the Environment and Earth Sciences, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 39040, Israel
| | - Yaeli Rosenberg
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Jennifer I C Benichou
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Celine Luisa D Campos
- The Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines
| | - Sherry Lyn G Sayco
- The Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines
| | - Michael Angelou L Nada
- The Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines
| | - Jake Ivan P Baquiran
- The Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines
| | - Charlon A Ligson
- The Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines
| | - Dror Avisar
- Porter School of the Environment and Earth Sciences, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 39040, Israel
| | - Cecilia Conaco
- The Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines
| | - Helga U Kuechly
- GFZ German Research Centre for Geosciences, 14473 Potsdam, Germany
| | - Christopher C M Kyba
- GFZ German Research Centre for Geosciences, 14473 Potsdam, Germany; Leibniz-Institute of Freshwater Ecology and Inland Fisheries, 12587 Berlin, Germany
| | - Patrick C Cabaitan
- The Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel.
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Levy O, Fernandes de Barros Marangoni L, I C Benichou J, Rottier C, Béraud E, Grover R, Ferrier-Pagès C. Artificial light at night (ALAN) alters the physiology and biochemistry of symbiotic reef building corals. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 266:114987. [PMID: 32622006 DOI: 10.1016/j.envpol.2020.114987] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 06/05/2020] [Accepted: 06/05/2020] [Indexed: 06/11/2023]
Abstract
Artificial Light at Night (ALAN), which is the alteration of natural light levels as the result of anthropogenic light sources, has been acknowledged as an important factor that alters the functioning of marine ecosystems. Using LEDs light to mimic ALAN, we studied the effect on the physiology (symbiont and chlorophyll contents, photosynthesis, respiration, pigment profile, skeletal growth, and oxidative stress responses) of two scleractinian coral species originating from the Red Sea. ALAN induced the photoinhibition of symbiont photosynthesis, as well as an overproduction of reactive oxygen species (ROS) and an increase in oxidative damage to lipids in both coral species. The extent of the deleterious effects of ALAN on the symbiotic association and coral physiology was aligned with the severity of the oxidative stress condition experienced by the corals. The coral species Sylophora pistillata, which experienced a more severe oxidative stress condition than the other species tested, Turbinaria reniformis, also showed a more pronounced bleaching (loss of symbionts and chlorophyll content), enhanced photoinhibition and decreased photosynthetic rates. Findings of the present study further our knowledge on the biochemical mechanisms underpinning the deleterious impacts of ALAN on scleractinian corals, ultimately shedding light on the emerging threat of ALAN on coral reef ecology. Further, considering that global warming and light pollution will increase in the next few decades, future studies should be taken to elucidate the potential synergetic effects of ALAN and global climate change stressors.
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Affiliation(s)
- Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 52900, Israel.
| | | | - Jennifer I C Benichou
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 52900, Israel
| | - Cécile Rottier
- Centre Scientifique de Monaco, Biologie Marine, Equipe d'Ecophysiologie, MC-98000, Monaco
| | - Eric Béraud
- Centre Scientifique de Monaco, Biologie Marine, Equipe d'Ecophysiologie, MC-98000, Monaco
| | - Renaud Grover
- Centre Scientifique de Monaco, Biologie Marine, Equipe d'Ecophysiologie, MC-98000, Monaco
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Chiu YL, Shikina S, Yoshioka Y, Shinzato C, Chang CF. De novo transcriptome assembly from the gonads of a scleractinian coral, Euphyllia ancora: molecular mechanisms underlying scleractinian gametogenesis. BMC Genomics 2020; 21:732. [PMID: 33087060 PMCID: PMC7579821 DOI: 10.1186/s12864-020-07113-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 09/29/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Sexual reproduction of scleractinians has captured the attention of researchers and the general public for decades. Although extensive ecological data has been acquired, underlying molecular and cellular mechanisms remain largely unknown. In this study, to better understand mechanisms underlying gametogenesis, we isolated ovaries and testes at different developmental phases from a gonochoric coral, Euphyllia ancora, and adopted a transcriptomic approach to reveal sex- and phase-specific gene expression profiles. In particular, we explored genes associated with oocyte development and maturation, spermiogenesis, sperm motility / capacitation, and fertilization. RESULTS 1.6 billion raw reads were obtained from 24 gonadal samples. De novo assembly of trimmed reads, and elimination of contigs derived from symbiotic dinoflagellates (Symbiodiniaceae) and other organisms yielded a reference E. ancora gonadal transcriptome of 35,802 contigs. Analysis of 4 developmental phases identified 2023 genes that were differentially expressed during oogenesis and 678 during spermatogenesis. In premature/mature ovaries, 631 genes were specifically upregulated, with 538 in mature testes. Upregulated genes included those involved in gametogenesis, gamete maturation, sperm motility / capacitation, and fertilization in other metazoans, including humans. Meanwhile, a large number of genes without homology to sequences in the SWISS-PROT database were also observed among upregulated genes in premature / mature ovaries and mature testes. CONCLUSIONS Our findings show that scleractinian gametogenesis shares many molecular characteristics with that of other metazoans, but it also possesses unique characteristics developed during cnidarian and/or scleractinian evolution. To the best of our knowledge, this study is the first to create a gonadal transcriptome assembly from any scleractinian. This study and associated datasets provide a foundation for future studies regarding gametogenesis and differences between male and female colonies from molecular and cellular perspectives. Furthermore, our transcriptome assembly will be a useful reference for future development of sex-specific and/or stage-specific germ cell markers that can be used in coral aquaculture and ecological studies.
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Affiliation(s)
- Yi-Ling Chiu
- Doctoral Program in Marine Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan.,Doctoral Program in Marine Biotechnology, Academia Sinica, Taipei, 11529, Taiwan
| | - Shinya Shikina
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, Taiwan. .,Center of Excellence for the Oceans, National Taiwan Ocean University, 2 Pei-Ning Rd, Keelung, 20224, Taiwan.
| | - Yuki Yoshioka
- Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba, 277-8564, Japan
| | - Chuya Shinzato
- Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba, 277-8564, Japan.
| | - Ching-Fong Chang
- Center of Excellence for the Oceans, National Taiwan Ocean University, 2 Pei-Ning Rd, Keelung, 20224, Taiwan. .,Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan.
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Baquiran JIP, Nada MAL, Campos CLD, Sayco SLG, Cabaitan PC, Rosenberg Y, Ayalon I, Levy O, Conaco C. The Prokaryotic Microbiome of Acropora digitifera is Stable under Short-Term Artificial Light Pollution. Microorganisms 2020; 8:E1566. [PMID: 33053643 PMCID: PMC7601249 DOI: 10.3390/microorganisms8101566] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 10/05/2020] [Accepted: 10/09/2020] [Indexed: 12/12/2022] Open
Abstract
Corals harbor a great diversity of symbiotic microorganisms that play pivotal roles in host nutrition, reproduction, and development. Changes in the ocean environment, such as increasing exposure to artificial light at night (ALAN), may alter these relationships and result in a decline in coral health. In this study, we examined the microbiome associated with gravid specimens of the reef-building coral Acropora digitifera. We also assessed the temporal effects of ALAN on the coral-associated microbial community using high-throughput sequencing of the 16S rRNA gene V4 hypervariable region. The A. digitifera microbial community was dominated by phyla Proteobacteria, Firmicutes, and Bacteroidetes. Exposure to ALAN had no large-scale effect on the coral microbiome, although taxa affiliated with Rhodobacteraceae, Caulobacteraceae, Burkholderiaceae, Lachnospiraceae, and Ruminococcaceae were significantly enriched in corals subjected to ALAN. We further noted an increase in the relative abundance of the family Endozoicomonadaceae (Endozoicomonas) as the spawning period approached, regardless of light treatment. These findings highlight the stability of the A. digitifera microbial community under short-term artificial light pollution and provide initial insights into the response of the collective holobiont to ALAN.
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Affiliation(s)
- Jake Ivan P. Baquiran
- Marine Science Institute, University of the Philippines Diliman, Quezon City 1101, Philippines; (J.I.P.B.); (M.A.L.N.); (C.L.D.C.); (S.L.G.S.); (P.C.C.)
| | - Michael Angelou L. Nada
- Marine Science Institute, University of the Philippines Diliman, Quezon City 1101, Philippines; (J.I.P.B.); (M.A.L.N.); (C.L.D.C.); (S.L.G.S.); (P.C.C.)
| | - Celine Luisa D. Campos
- Marine Science Institute, University of the Philippines Diliman, Quezon City 1101, Philippines; (J.I.P.B.); (M.A.L.N.); (C.L.D.C.); (S.L.G.S.); (P.C.C.)
| | - Sherry Lyn G. Sayco
- Marine Science Institute, University of the Philippines Diliman, Quezon City 1101, Philippines; (J.I.P.B.); (M.A.L.N.); (C.L.D.C.); (S.L.G.S.); (P.C.C.)
| | - Patrick C. Cabaitan
- Marine Science Institute, University of the Philippines Diliman, Quezon City 1101, Philippines; (J.I.P.B.); (M.A.L.N.); (C.L.D.C.); (S.L.G.S.); (P.C.C.)
| | - Yaeli Rosenberg
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel; (Y.R.); (I.A.); (O.L.)
| | - Inbal Ayalon
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel; (Y.R.); (I.A.); (O.L.)
- Israel The H. Steinitz Marine Biology Laboratory, The Interuniversity Institute for Marine Sciences of Eilat, P.O. Box 469, Eilat 88103, Israel
- Porter School of the Environment and Earth Sciences, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 39040, Israel
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel; (Y.R.); (I.A.); (O.L.)
| | - Cecilia Conaco
- Marine Science Institute, University of the Philippines Diliman, Quezon City 1101, Philippines; (J.I.P.B.); (M.A.L.N.); (C.L.D.C.); (S.L.G.S.); (P.C.C.)
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Dixon G, Abbott E, Matz M. Meta-analysis of the coral environmental stress response: Acropora corals show opposing responses depending on stress intensity. Mol Ecol 2020; 29:2855-2870. [PMID: 32615003 DOI: 10.1111/mec.15535] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 05/25/2020] [Accepted: 06/18/2020] [Indexed: 12/15/2022]
Abstract
As climate change progresses, reef-building corals must contend more often with suboptimal conditions, motivating a need to understand coral stress response. Here, we test the hypothesis that there is a stereotyped transcriptional response that corals enact under all stressful conditions, functionally characterized by downregulation of growth, and activation of cell death, response to reactive oxygen species, immunity, and protein folding and degradation. We analyse RNA-seq and Tag-Seq data from 14 previously published studies and supplement them with four new experiments involving different stressors, totaling over 600 gene expression profiles from the genus Acropora. Contrary to expectations, we found not one, but two distinct types of response. The type A response was observed under all kinds of high-intensity stress, was correlated between independent projects and was functionally consistent with the hypothesized stereotyped response. The consistent correlation between projects, irrespective of stress type, supports the type A response as the general coral environmental stress response (ESR), a blanket solution to severely stressful conditions. The distinct type B response was observed under lower intensity stress and was more variable among studies. Unexpectedly, at the level of individual genes and functional categories, the type B response was broadly opposite the type A response. Finally, taking advantage of the breadth of the data set, we present contextual annotations for previously unannotated genes based on consistent stress-induced differences across independent projects.
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Affiliation(s)
- Groves Dixon
- Department of Integrative Biology, University of Texas, Austin, TX, USA
| | - Evelyn Abbott
- Department of Integrative Biology, University of Texas, Austin, TX, USA
| | - Mikhail Matz
- Department of Integrative Biology, University of Texas, Austin, TX, USA
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Andreatta G, Tessmar-Raible K. The Still Dark Side of the Moon: Molecular Mechanisms of Lunar-Controlled Rhythms and Clocks. J Mol Biol 2020; 432:3525-3546. [PMID: 32198116 PMCID: PMC7322537 DOI: 10.1016/j.jmb.2020.03.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/18/2020] [Accepted: 03/09/2020] [Indexed: 12/22/2022]
Abstract
Starting with the beginning of the last century, a multitude of scientific studies has documented that the lunar cycle times behaviors and physiology in many organisms. It is plausible that even the first life forms adapted to the different rhythms controlled by the moon. Consistently, many marine species exhibit lunar rhythms, and also the number of documented "lunar-rhythmic" terrestrial species is increasing. Organisms follow diverse lunar geophysical/astronomical rhythms, which differ significantly in terms of period length: from hours (circalunidian and circatidal rhythms) to days (circasemilunar and circalunar cycles). Evidence for internal circatital and circalunar oscillators exists for a range of species based on past behavioral studies, but those species with well-documented behaviorally free-running lunar rhythms are not typically used for molecular studies. Thus, the underlying molecular mechanisms are largely obscure: the dark side of the moon. Here we review findings that start to connect molecular pathways with moon-controlled physiology and behaviors. The present data indicate connections between metabolic/endocrine pathways and moon-controlled rhythms, as well as interactions between circadian and circatidal/circalunar rhythms. Moreover, recent high-throughput analyses provide useful leads toward pathways, as well as molecular markers. However, for each interpretation, it is important to carefully consider the, partly substantially differing, conditions used in each experimental paradigm. In the future, it will be important to use lab experiments to delineate the specific mechanisms of the different solar- and lunar-controlled rhythms, but to also start integrating them together, as life has evolved equally long under rhythms of both sun and moon.
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Affiliation(s)
- Gabriele Andreatta
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria; Research Platform "Rhythms of Life", University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Kristin Tessmar-Raible
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria; Research Platform "Rhythms of Life", University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria.
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35
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Leach WB, Reitzel AM. Decoupling behavioral and transcriptional responses to color in an eyeless cnidarian. BMC Genomics 2020; 21:361. [PMID: 32410571 PMCID: PMC7222589 DOI: 10.1186/s12864-020-6766-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 04/30/2020] [Indexed: 12/30/2022] Open
Abstract
Background Animals have specific molecular, physiological, and behavioral responses to light that are influenced by wavelength and intensity. Predictable environmental changes – predominantly solar and lunar cycles – drive endogenous daily oscillations by setting internal pacemakers, otherwise known as the circadian clock. Cnidarians have been a focal group to discern the evolution of light responsiveness due to their phylogenetic position as a sister phylum to bilaterians and broad range of light-responsive behaviors and physiology. Marine species that occupy a range of depths will experience different ranges of wavelengths and light intensities, which may result in variable phenotypic responses. Here, we utilize the eyeless sea anemone Nematostella vectensis, an estuarine anemone that typically resides in shallow water habitats, to compare behavioral and molecular responses when exposed to different light conditions. Results Quantitative measures of locomotion clearly showed that this species responds to light in the blue and green spectral range with a circadian activity profile, in contrast to a circatidal activity profile in the red spectral range and in constant darkness. Differences in average day/night locomotion was significant in each condition, with overall peak activity during the dark period. Comparative analyses of 96 transcriptomes from individuals sampled every 4 h in each lighting treatment revealed complex differences in gene expression between colors, including in many of the genes likely involved in the cnidarian circadian clock. Transcriptional profiling showed the majority of genes are differentially expressed when comparing mid-day with mid-night, and mostly in red light. Gene expression profiles were largely unique in each color, although animals in blue and green were overall more similar to each other than to red light. Conclusions Together, these analyses support the hypothesis that cnidarians are sensitive to red light, and this perception results in a rich transcriptional and divergent behavioral response. Future work determining the specific molecular mechanisms driving the circadian and potential circatidal rhythms measured here would be impactful to connect gene expression variation with behavioral variation in this eyeless species.
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Affiliation(s)
- Whitney B Leach
- Department of Biological Sciences, University of North Carolina at Charlotte, 9201 University City Blvd, Woodward Hall, Room 381A, Charlotte, NC, 28223, USA.
| | - Adam M Reitzel
- Department of Biological Sciences, University of North Carolina at Charlotte, 9201 University City Blvd, Woodward Hall, Room 381A, Charlotte, NC, 28223, USA
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36
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Dominoni DM, Halfwerk W, Baird E, Buxton RT, Fernández-Juricic E, Fristrup KM, McKenna MF, Mennitt DJ, Perkin EK, Seymoure BM, Stoner DC, Tennessen JB, Toth CA, Tyrrell LP, Wilson A, Francis CD, Carter NH, Barber JR. Why conservation biology can benefit from sensory ecology. Nat Ecol Evol 2020; 4:502-511. [PMID: 32203474 DOI: 10.1038/s41559-020-1135-4] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 01/30/2020] [Indexed: 11/09/2022]
Abstract
Global expansion of human activities is associated with the introduction of novel stimuli, such as anthropogenic noise, artificial lights and chemical agents. Progress in documenting the ecological effects of sensory pollutants is weakened by sparse knowledge of the mechanisms underlying these effects. This severely limits our capacity to devise mitigation measures. Here, we integrate knowledge of animal sensory ecology, physiology and life history to articulate three perceptual mechanisms-masking, distracting and misleading-that clearly explain how and why anthropogenic sensory pollutants impact organisms. We then link these three mechanisms to ecological consequences and discuss their implications for conservation. We argue that this framework can reveal the presence of 'sensory danger zones', hotspots of conservation concern where sensory pollutants overlap in space and time with an organism's activity, and foster development of strategic interventions to mitigate the impact of sensory pollutants. Future research that applies this framework will provide critical insight to preserve the natural sensory world.
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Affiliation(s)
- Davide M Dominoni
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK. .,Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands.
| | - Wouter Halfwerk
- Department of Ecological Science, Section Animal Ecology, VU University Amsterdam, Amsterdam, The Netherlands
| | - Emily Baird
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Rachel T Buxton
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, CO, USA
| | | | - Kurt M Fristrup
- National Park Service, Natural Sounds and Night Skies Division, Fort Collins, CO, USA
| | - Megan F McKenna
- National Park Service, Natural Sounds and Night Skies Division, Fort Collins, CO, USA
| | | | - Elizabeth K Perkin
- Environmental Monitoring and Assessment Group, Hatfield Consultants, Calgary, Alberta, Canada
| | - Brett M Seymoure
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, CO, USA
| | - David C Stoner
- Department of Wildland Resources, Utah State University, Logan, UT, USA
| | | | - Cory A Toth
- Canadian Wildlife Service, Environment and Climate Change Canada, Gatineau, Quebec, Canada
| | - Luke P Tyrrell
- Department of Biological Sciences, State University of New York at Plattsburgh, Plattsburgh, NY, USA
| | - Ashley Wilson
- Department of Biological Sciences, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Clinton D Francis
- Department of Biological Sciences, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Neil H Carter
- School for Environment and Sustainability, University of Michigan, Ann Arbor, MI, USA
| | - Jesse R Barber
- Department of Biological Sciences, Boise State University, Boise, ID, USA
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37
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Häfker NS, Tessmar-Raible K. Rhythms of behavior: are the times changin’? Curr Opin Neurobiol 2020; 60:55-66. [DOI: 10.1016/j.conb.2019.10.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 10/25/2019] [Accepted: 10/29/2019] [Indexed: 02/07/2023]
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38
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Tamir R, Eyal G, Cohen I, Loya Y. Effects of Light Pollution on the Early Life Stages of the Most Abundant Northern Red Sea Coral. Microorganisms 2020; 8:microorganisms8020193. [PMID: 32023896 PMCID: PMC7074826 DOI: 10.3390/microorganisms8020193] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 11/16/2022] Open
Abstract
The growth in human population along coastal areas is exposing marine environments to increasing anthropogenic light sources. Despite the potential effects of this modern phenomenon, very few studies have examined its implications for corals. Here, we present a long-term study of coral early life stages under light pollution conditions at night. Coral larvae were collected from Stylophora pistillata colonies, and then settled and grown under experimental conditions of two different common city lighting methods (fluorescent or LED). Effects of the artificial lighting on the coral settlement success, survivorship, growth rate, photosynthetic efficiency, and calcification rate were examined over a period of one year. The control exhibited ~30% higher settlement success compared to the two light treatments, while under the light treatments corals showed higher survivorship, growth, and calcification rates. In addition, an indication of damage to the photosynthetic system was found in the light-polluted corals, which was reflected in their photosynthesis efficiency parameters: i.e., lower maximum light utilization coefficient (α), lower maximum potential photosynthetic rate (Pmax), and lower photosynthetic maximal quantum yield (Fv/Fm). Our findings provide evidence of the potential adverse effects of artificial lighting methods on the natural environment of coral reefs. We conclude that the use of the LED lighting method has high interference potential for the early life stages of corals.
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Affiliation(s)
- Raz Tamir
- School of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel;
- The Interuniversity Institute for Marine Sciences in Eilat, Eilat 8810302, Israel;
- Correspondence:
| | - Gal Eyal
- ARC Centre of Excellence for Coral Reef Studies, School of Biological Sciences, University of Queensland, St. Lucia, QLD 4072, Australia;
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Itay Cohen
- The Interuniversity Institute for Marine Sciences in Eilat, Eilat 8810302, Israel;
- Department of Oceanography, The Institute of Earth Sciences, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Yossi Loya
- School of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel;
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39
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Sakai Y, Hatta M, Furukawa S, Kawata M, Ueno N, Maruyama S. Environmental factors explain spawning day deviation from full moon in the scleractinian coral Acropora. Biol Lett 2020; 16:20190760. [PMID: 31964259 PMCID: PMC7013481 DOI: 10.1098/rsbl.2019.0760] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Broadcast-spawning scleractinian corals annually release their gametes with high levels of synchrony, both within and among species. However, the timing of spawning can vary inter-annually. In particular, the night of spawning relative to the full moon phase can vary considerably among years at some locations. Although multiple environmental factors can affect the night of spawning, their effects have not been quantitatively assessed at the multi-regional level. In this study, we analysed environmental factors that are potentially correlated with spawning day deviation, in relation to the full moon phase, in Acropora corals inhabiting seven reefs in Australia and Japan. We accordingly found that sea surface temperature and wind speed within one to two months prior to the full moon of the spawning month were strongly correlated with spawning day deviations. In addition, solar flux had a weak effect on the night of spawning. These findings indicate that Acropora have the capacity to adjust their development and physiology in response to environmental factors for fine-tuning the timing of synchronous spawning, thereby maximizing reproductive success and post-fertilization survival.
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Affiliation(s)
- Yusuke Sakai
- Division of Morphogenesis, National Institute for Basic Biology, Okazaki, Aichi, Japan
| | - Masayuki Hatta
- Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo, Japan
| | - Seishiro Furukawa
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Masakado Kawata
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Naoto Ueno
- Division of Morphogenesis, National Institute for Basic Biology, Okazaki, Aichi, Japan.,Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
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40
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Whitlock K. Evolutionarily conserved peptides coordinate lunar phase and metabolism. Proc Natl Acad Sci U S A 2020; 117:805-807. [PMID: 31888992 PMCID: PMC6969539 DOI: 10.1073/pnas.1920432117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Kathleen Whitlock
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Universidad de Valparaíso, 2340000 Valparaíso, Chile
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41
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Shlesinger T, Loya Y. Breakdown in spawning synchrony: A silent threat to coral persistence. Science 2019; 365:1002-1007. [PMID: 31488683 DOI: 10.1126/science.aax0110] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 07/16/2019] [Indexed: 01/14/2023]
Abstract
The impacts of human and natural disturbances on coral reefs are typically quantified through visible damage (e.g., reduced coral coverage as a result of bleaching events), but changes in environmental conditions may also cause damage in less visible ways. Despite the current paradigm, which suggests consistent, highly synchronized spawning events, corals that reproduce by broadcast spawning are particularly vulnerable because their reproductive phenology is governed by environmental cues. Here, we quantify coral spawning intensity during four annual reproductive seasons, alongside laboratory analyses at the polyp, colony, and population levels, and we demonstrate that, compared with historical data, several species from the Red Sea have lost their reproductive synchrony. Ultimately, such a synchrony breakdown reduces the probability of successful fertilization, leading to a dearth of new recruits, which may drive aging populations to extinction.
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Affiliation(s)
- Tom Shlesinger
- School of Zoology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Yossi Loya
- School of Zoology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel
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42
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Ayalon I, de Barros Marangoni LF, Benichou JIC, Avisar D, Levy O. Red Sea corals under Artificial Light Pollution at Night (ALAN) undergo oxidative stress and photosynthetic impairment. GLOBAL CHANGE BIOLOGY 2019; 25:4194-4207. [PMID: 31512309 PMCID: PMC6900201 DOI: 10.1111/gcb.14795] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 07/22/2019] [Accepted: 07/23/2019] [Indexed: 05/22/2023]
Abstract
Coral reefs represent the most diverse marine ecosystem on the planet, yet they are undergoing an unprecedented decline due to a combination of increasing global and local stressors. Despite the wealth of research investigating these stressors, Artificial Light Pollution at Night (ALAN) or "ecological light pollution" represents an emerging threat that has received little attention in the context of coral reefs, despite the potential of disrupting the chronobiology, physiology, behavior, and other biological processes of coral reef organisms. Scleractinian corals, the framework builders of coral reefs, depend on lunar illumination cues to synchronize their biological rhythms such as behavior, reproduction and physiology. While, light pollution (POL) may mask and lead de-synchronization of these biological rhythms process. To reveal if ALAN impacts coral physiology, we have studied two coral species, Acropora eurystoma and Pocillopora damicornis, from the Gulf of Eilat/Aqaba, Red Sea, which is undergoing urban development that has led to severe POL at night. Our two experimental design data revealed that corals exposed to ALAN face an oxidative stress condition, show lower photosynthesis performances measured by electron transport rate (ETR), as well as changes in chlorophyll and algae density parameters. Testing different lights such as Blue LED and White LED spectrum showed more extreme impact in comparison to Yellow LEDs on coral physiology. The finding of this work sheds light on the emerging threat of POL and the impacts on the biology and ecology of Scleractinian corals, and will help to formulate specific management implementations to mitigate its potentially harmful impacts.
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Affiliation(s)
- Inbal Ayalon
- Mina and Everard Goodman Faculty of Life SciencesBar‐Ilan UniversityRamat GanIsrael
- Israel The H. Steinitz Marine Biology LaboratoryThe Interuniversity Institute for Marine Sciences of EilatEilatIsrael
- Porter School of the Environment and Earth SciencesFaculty of Exact SciencesTel Aviv UniversityTel AvivIsrael
| | | | | | - Dror Avisar
- Porter School of the Environment and Earth SciencesFaculty of Exact SciencesTel Aviv UniversityTel AvivIsrael
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life SciencesBar‐Ilan UniversityRamat GanIsrael
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43
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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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44
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Tarrant AM, Helm RR, Levy O, Rivera HE. Environmental entrainment demonstrates natural circadian rhythmicity in the cnidarian Nematostella vectensis. ACTA ACUST UNITED AC 2019; 222:jeb.205393. [PMID: 31611292 DOI: 10.1242/jeb.205393] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 10/10/2019] [Indexed: 12/21/2022]
Abstract
Considerable advances in chronobiology have been made through controlled laboratory studies, but distinct temporal rhythms can emerge under natural environmental conditions. Lab-reared Nematostella vectensis sea anemones exhibit circadian behavioral and physiological rhythms. Given that these anemones inhabit shallow estuarine environments subject to tidal inputs, it was unclear whether circadian rhythmicity would persist following entrainment in natural conditions, or whether circatidal periodicity would predominate. Nematostella were conditioned within a marsh environment, where they experienced strong daily temperature cycles as well as brief tidal flooding around the full and new moons. Upon retrieval, anemones exhibited strong circadian (∼24 h) activity rhythms under a light-dark cycle or continuous darkness, but reduced circadian rhythmicity under continuous light. However, some individuals in each light condition showed circadian rhythmicity, and a few individuals showed circatidal rhythmicity. Consistent with the behavioral studies, a large number of transcripts (1640) exhibited diurnal rhythmicity compared with very few (64) with semidiurnal rhythmicity. Diurnal transcripts included core circadian regulators, and 101 of 434 (23%) genes that were previously found to be upregulated by exposure to ultraviolet radiation. Together, these behavioral and transcriptional studies show that circadian rhythmicity predominates and suggest that solar radiation drives physiological cycles in this sediment-dwelling subtidal animal.
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Affiliation(s)
- Ann M Tarrant
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole MA 02543, USA
| | - Rebecca R Helm
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole MA 02543, USA.,Biology Department, University of North Carolina Asheville, Asheville NC 28804, USA
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Hanny E Rivera
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole MA 02543, USA.,Biology Department, Boston University, Boston MA 02215, USA
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45
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Wuitchik DM, Wang D, Pells TJ, Karimi K, Ward S, Vize PD. Seasonal temperature, the lunar cycle and diurnal rhythms interact in a combinatorial manner to modulate genomic responses to the environment in a reef-building coral. Mol Ecol 2019; 28:3629-3641. [PMID: 31294494 PMCID: PMC6851572 DOI: 10.1111/mec.15173] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 06/14/2019] [Accepted: 06/28/2019] [Indexed: 12/15/2022]
Abstract
Rhythms of various periodicities drive cyclical processes in organisms ranging from single cells to the largest mammals on earth, and on scales from cellular physiology to global migrations. The molecular mechanisms that generate circadian behaviours in model organisms have been well studied, but longer phase cycles and interactions between cycles with different periodicities remain poorly understood. Broadcast spawning corals are one of the best examples of an organism integrating inputs from multiple environmental parameters, including seasonal temperature, the lunar phase and hour of the day, to calibrate their annual reproductive event. We present a deep RNA-sequencing experiment utilizing multiple analyses to differentiate transcriptomic responses modulated by the interactions between the three aforementioned environmental parameters. Acropora millepora was sampled over multiple 24-hr periods throughout a full lunar month and at two seasonal temperatures. Temperature, lunar and diurnal cycles produce distinct transcriptomic responses, with interactions between all three variables identifying a core set of genes. These core genes include mef2, a developmental master regulator, and two heterogeneous nuclear ribonucleoproteins, one of which is known to post-transcriptionally interact with mef2 and with biological clock-regulating mRNAs. Interactions between diurnal and temperature differences impacted a range of core processes ranging from biological clocks to stress responses. Genes involved with developmental processes and transcriptional regulation were impacted by the lunar phase and seasonal temperature differences. Lastly, there was a diurnal and lunar phase interaction in which genes involved with RNA-processing and translational regulation were differentially regulated. These data illustrate the extraordinary levels of transcriptional variation across time in a simple radial cnidarian in response to the environment under normal conditions.
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Affiliation(s)
- Daniel M Wuitchik
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - DongZhuo Wang
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Troy J Pells
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Kamran Karimi
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Selina Ward
- Department of Biological Sciences, The University of Queensland, St. Lucia, Qld, Australia
| | - Peter D Vize
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada.,Department of Biological Sciences, The University of Queensland, St. Lucia, Qld, Australia
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46
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Rosenberg Y, Doniger T, Levy O. Sustainability of coral reefs are affected by ecological light pollution in the Gulf of Aqaba/Eilat. Commun Biol 2019; 2:289. [PMID: 31396569 PMCID: PMC6683144 DOI: 10.1038/s42003-019-0548-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 07/15/2019] [Indexed: 01/12/2023] Open
Abstract
As human populations grow and lighting technologies improve, artificial light gradually alters natural cycles of light and dark that have been consistent over long periods of geological and evolutionary time. While considerable ecological implications of artificial light have been identified in both terrestrial and aquatic habitats, knowledge about the physiological and molecular effects of light pollution is vague. To determine if ecological light pollution (ELP) impacts coral biological processes, we characterized the transcriptome of the coral Acropora eurystoma under two different light regimes: control conditions and treatment with light at night. Here we show that corals exposed to ELP have approximately 25 times more differentially expressed genes that regulate cell cycle, cell proliferation, cell growth, protein synthesis and display changes in photo physiology. The finding of this work confirms that ELP acts as a chronic disturbance that may impact the future of 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
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 52900 Israel
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47
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Ziegler M, Roik A, Röthig T, Wild C, Rädecker N, Bouwmeester J, Voolstra CR. Ecophysiology of Reef-Building Corals in the Red Sea. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/978-3-030-05802-9_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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48
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Schenk S, Bannister SC, Sedlazeck FJ, Anrather D, Minh BQ, Bileck A, Hartl M, von Haeseler A, Gerner C, Raible F, Tessmar-Raible K. Combined transcriptome and proteome profiling reveals specific molecular brain signatures for sex, maturation and circalunar clock phase. eLife 2019; 8:e41556. [PMID: 30767890 PMCID: PMC6377233 DOI: 10.7554/elife.41556] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Accepted: 01/15/2019] [Indexed: 12/15/2022] Open
Abstract
Many marine animals, ranging from corals to fishes, synchronise reproduction to lunar cycles. In the annelid Platynereis dumerilii, this timing is orchestrated by an endogenous monthly (circalunar) clock entrained by moonlight. Whereas daily (circadian) clocks cause extensive transcriptomic and proteomic changes, the quality and quantity of regulations by circalunar clocks have remained largely elusive. By establishing a combined transcriptomic and proteomic profiling approach, we provide first systematic insight into the molecular changes in Platynereis heads between circalunar phases, and across sexual differentiation and maturation. Whereas maturation elicits large transcriptomic and proteomic changes, the circalunar clock exhibits only minor transcriptomic, but strong proteomic regulation. Our study provides a versatile extraction technique and comprehensive resources. It corroborates that circadian and circalunar clock effects are likely distinct and identifies key molecular brain signatures for reproduction, sex and circalunar clock phase. Examples include prepro-whitnin/proctolin and ependymin-related proteins as circalunar clock targets.
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Affiliation(s)
- Sven Schenk
- Max F Perutz Laboratories, University of Vienna, Vienna BioCenter, Vienna, Austria
- Research Platform 'Rhythms of Life', University of Vienna, Vienna BioCenter, Vienna, Austria
| | - Stephanie C Bannister
- Max F Perutz Laboratories, University of Vienna, Vienna BioCenter, Vienna, Austria
- Research Platform 'Rhythms of Life', University of Vienna, Vienna BioCenter, Vienna, Austria
| | - Fritz J Sedlazeck
- Center of Integrative Bioinformatics Vienna, Max F Perutz Laboratories, University of Vienna, Medical University of Vienna, Vienna BioCenter, Vienna, Austria
| | - Dorothea Anrather
- Max F Perutz Laboratories, University of Vienna, Vienna BioCenter, Vienna, Austria
- Mass Spectrometry Facility, Max F Perutz Laboratories, Vienna, Austria
| | - Bui Quang Minh
- Center of Integrative Bioinformatics Vienna, Max F Perutz Laboratories, University of Vienna, Medical University of Vienna, Vienna BioCenter, Vienna, Austria
| | - Andrea Bileck
- Research Platform 'Rhythms of Life', University of Vienna, Vienna BioCenter, Vienna, Austria
- Department of Analytical Chemistry, University of Vienna, Vienna, Austria
| | - Markus Hartl
- Max F Perutz Laboratories, University of Vienna, Vienna BioCenter, Vienna, Austria
- Mass Spectrometry Facility, Max F Perutz Laboratories, Vienna, Austria
| | - Arndt von Haeseler
- Research Platform 'Rhythms of Life', University of Vienna, Vienna BioCenter, Vienna, Austria
- Center of Integrative Bioinformatics Vienna, Max F Perutz Laboratories, University of Vienna, Medical University of Vienna, Vienna BioCenter, Vienna, Austria
- Bioinformatics and Computational Biology, Faculty of Computer Science, University of Vienna, Vienna, Austria
| | - Christopher Gerner
- Research Platform 'Rhythms of Life', University of Vienna, Vienna BioCenter, Vienna, Austria
- Department of Analytical Chemistry, University of Vienna, Vienna, Austria
| | - Florian Raible
- Max F Perutz Laboratories, University of Vienna, Vienna BioCenter, Vienna, Austria
- Research Platform 'Rhythms of Life', University of Vienna, Vienna BioCenter, Vienna, Austria
| | - Kristin Tessmar-Raible
- Research Platform 'Rhythms of Life', University of Vienna, Vienna BioCenter, Vienna, Austria
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Taubner I, Hu MY, Eisenhauer A, Bleich M. Electrophysiological evidence for light-activated cation transport in calcifying corals. Proc Biol Sci 2019; 286:20182444. [PMID: 30963934 PMCID: PMC6408601 DOI: 10.1098/rspb.2018.2444] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/23/2019] [Indexed: 12/17/2022] Open
Abstract
Light has been demonstrated to enhance calcification rates in hermatypic coral species. To date, it remains unresolved whether calcifying epithelia change their ion transport activity during illumination, and whether such a process is mediated by the endosymbiotic algae or can be controlled by the coral host itself. Using a modified Ussing chamber in combination with H+ sensitive microelectrode measurements, the present work demonstrates that light triggers the generation of a skeleton positive potential of up to 0.9 mV in the hermatypic coral Stylophora pistillata. This potential is generated by a net flux of cations towards the skeleton and reaches its maximum at blue (450 nm) light. The effects of pharmacological inhibitors targeting photosynthesis 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) and anion transport 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) were investigated by pH microelectrode measurements in coral tissues demonstrating a rapid decrease in tissue pH under illumination. However, these inhibitors showed no effect on the electrophysiological light response of the coral host. By contrast, metabolic inhibition by cyanide and deoxyglucose reversibly inhibited the light-induced cation flux towards the skeleton. These results suggest that ion transport across coral epithelia is directly triggered by blue light, independent of photosynthetic activity of algal endosymbionts. Measurements of this very specific and quantifiable physiological response can provide parameters to identify photoreception mechanisms and will help to broaden our understanding of the mechanistic link between light stimulation and epithelial ion transport, potentially relevant for calcification in hermatypic corals.
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Affiliation(s)
- Isabelle Taubner
- Christian-Albrechts-Universität, Institute of Physiology, Kiel, Germany
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
| | - Marian Y. Hu
- Christian-Albrechts-Universität, Institute of Physiology, Kiel, Germany
| | | | - Markus Bleich
- Christian-Albrechts-Universität, Institute of Physiology, Kiel, Germany
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Álvarez-Campos P, Kenny NJ, Verdes A, Fernández R, Novo M, Giribet G, Riesgo A. Delegating Sex: Differential Gene Expression in Stolonizing Syllids Uncovers the Hormonal Control of Reproduction. Genome Biol Evol 2019; 11:295-318. [PMID: 30535381 PMCID: PMC6350857 DOI: 10.1093/gbe/evy265] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/09/2018] [Indexed: 12/31/2022] Open
Abstract
Stolonization in syllid annelids is a unique mode of reproduction among animals. During the breeding season, a structure resembling the adult but containing only gametes, called stolon, is formed generally at the posterior end of the animal. When stolons mature, they detach from the adult and gametes are released into the water column. The process is synchronized within each species, and it has been reported to be under environmental and endogenous control, probably via endocrine regulation. To further understand reproduction in syllids and to elucidate the molecular toolkit underlying stolonization, we generated Illumina RNA-seq data from different tissues of reproductive and nonreproductive individuals of Syllis magdalena and characterized gene expression during the stolonization process. Several genes involved in gametogenesis (ovochymase, vitellogenin, testis-specific serine/threonine-kinase), immune response (complement receptor 2), neuronal development (tyrosine-protein kinase Src42A), cell proliferation (alpha-1D adrenergic receptor), and steroid metabolism (hydroxysteroid dehydrogenase 2) were found differentially expressed in the different tissues and conditions analyzed. In addition, our findings suggest that several neurohormones, such as methyl farnesoate, dopamine, and serotonin, might trigger stolon formation, the correct maturation of gametes and the detachment of stolons when gametogenesis ends. The process seems to be under circadian control, as indicated by the expression patterns of r-opsins. Overall, our results shed light into the genes that orchestrate the onset of gamete formation and improve our understanding of how some hormones, previously reported to be involved in reproduction and metamorphosis processes in other invertebrates, seem to also regulate reproduction via stolonization.
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Affiliation(s)
- Patricia Álvarez-Campos
- Facultad de Ciencias, Departamento de Biología (Zoología), Universidad Autónoma de Madrid, Spain
- Museum of Comparative Zoology, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts
- Department of Life Sciences, The Natural History Museum of London, London, United Kingdom
- Department of Biological & Medical Sciences, Oxford Brookes University, Headington Campus, Gipsy Lane, Oxford, United Kingdom
| | - Nathan J Kenny
- Department of Life Sciences, The Natural History Museum of London, London, United Kingdom
| | - Aida Verdes
- Facultad de Ciencias, Departamento de Biología (Zoología), Universidad Autónoma de Madrid, Spain
- Department of Biology, The Graduate Center, City University of New York
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, New York
| | - Rosa Fernández
- Bioinformatics & Genomics Unit, Center for Genomic Regulation, Barcelona, Spain
| | - Marta Novo
- Facultad de Biología, Departamento de Biodiversidad, Ecología y Evolución, Universidad Complutense de Madrid, Spain
| | - Gonzalo Giribet
- Museum of Comparative Zoology, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts
| | - Ana Riesgo
- Department of Biology, The Graduate Center, City University of New York
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