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Sample records for morandini 1997cnidaria scyphozoa

  1. Nematocytes' activation in Pelagia noctiluca (Cnidaria, Scyphozoa) oral arms.

    PubMed

    Morabito, R; Marino, A; La Spada, G

    2012-06-01

    Nematocytes' discharge is triggered to perform both defense and predation strategies in cnidarians and occurs under chemico-physical stimulation. In this study, different compounds such as amino acids and proteins (mucin, albumin, poly-L: -lysine, trypsin), sugars and N-acetylate sugars (N-acetyl neuraminic acid, N-acetyl galactosamine, sucrose, glucose, agarose and trehalose), nucleotides (ATP and cAMP), were tested as chemosensitizers of nematocyte discharge in the oral arms of the scyphozoan Pelagia noctiluca, particularly abundant in the Strait of Messina (Italy). Excised oral arms were submitted to a combined chemico-physical stimulation by treatment with different compounds followed by mechanical stimulation by a non-vibrating test probe. Discharge induced by a chemico-physical stimulation was more significant than that obtained after mechanical stimulation alone. A chemosensitizing mechanism, with a dose-dependent effect, was observed after treatment with sugars, amino compounds such as glutathione, nucleotides and mucin, according to that already seen in sea anemones. Such findings suggest that, though Anthozoa and Scyphozoa exhibit different divergence times during the evolutionary process, the discharge activation exhibits common features, probably derived from their last common ancestor.

  2. Cultivation of polyps and medusae of Coronatae (Cnidaria, Scyphozoa) with a brief review of important characters

    NASA Astrophysics Data System (ADS)

    Jarms, Gerhard; Morandini, André Carrara; da Silveira, Fábio Lang

    2002-09-01

    This work is a concise guide to the methods, techniques and equipment needed for the collection and transport of specimens, for arranging, maintaining and controlling cultures, for handling polyps, ephyrae, medusae and/or planuloids, and for standardising species description on the basis of life-cycle studies of Scyphozoa Coronatae. Objective characteristics meaningful to systematics are listed and illustrated. Suggestions for important literature sources are given, mainly on the rearing of metagenetic cnidarians in the laboratory.

  3. [Shape conservatism and shaping variability. The comparative analysis of Hydrozoa and Scyphozoa early development].

    PubMed

    Kraus, Iu A

    2002-01-01

    The morphogenetic pathways based on the self-organization take an important part in the early development of White Sea Cnidarians--Dynamena pumila (Hydrozoa) and Aurelia aurita (Scyphozoa). Comparative analysis of their early development revealed two patterns of embryonic spatial structure reproduced in the morphogenesis of both species in spite of the differences of morphogenetic paths. These are toroidal and bilaterally symmetrical shapes. It is possible that these shapes correspond to the equilibrium states of developing system and their stable reproduction is a result of epigenetic rather than genetic program.

  4. Induction of metamorphosis from the larval to the polyp stage is similar in Hydrozoa and a subgroup of Scyphozoa (Cnidaria, Semaeostomeae)

    NASA Astrophysics Data System (ADS)

    Siefker, Barbara; Kroiher, Michael; Berking, Stefan

    2000-12-01

    Larvae of cnidarians need an external cue for metamorphosis to start. The larvae of various hydrozoa, in particular of Hydractinia echinata, respond to Cs+, Li+, NH4 + and seawater in which the concentration of Mg2+ ions is reduced. They further respond to the phorbolester, tetradecanoyl-phorbol-13-acetate (TPA) and the diacylglycerol (DAG) diC8, which both are argued to stimulate a protein kinase C. The only well-studied scyphozoa, Cassiopea spp., respond differently, i.e. to TPA and diC8 only. We found that larvae of the scyphozoa Aurelia aurita, Chrysaora hysoscella and Cyanea lamarckii respond to all the compounds mentioned. Trigonelline ( N-methylnicotinic acid), a metamorphosis inhibitor found in Hydractinia larvae, is assumed to act by delivering a methyl group for transmethylation processes antagonising metamorphosis induction in Chrysaora hysoscella and Cyanea lamarckii. The three species tested are scyphozoa belonging to the subgroup of semaeostomeae, while Cassiopea spp. belong to the rhizostomeae. The results obtained may contribute to the discussion concerning the evolution of cnidarians and may help to clarify whether the way metamorphosis can be induced in rhizostomeae as a whole is different from that in hydrozoa and those scyphozoa belonging to the subgroup semaeostomeae.

  5. Cardiovascular effects of Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom in rats.

    PubMed

    Kim, Euikyung; Lee, Seunghwan; Kim, Jong-Shu; Yoon, Won Duk; Lim, Donghyun; Hart, Andrew J; Hodgson, Wayne C

    2006-12-15

    Over the past few years, populations of the giant jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) have increased dramatically in the waters of China, Korea, and Japan without any definitive reason. This has resulted in severe damage to fisheries in the areas. During a pilot study, we observed that the venom of N. nomurai produced a functional cardiac depression in mice. However, the mechanism of action was not examined. In the present study, we investigated the cardiovascular effects of nematocyst-derived venom from N. nomurai in anesthetized rats. Venom (0.1-2.4 mg protein/kg, i.v.) produced dose-dependent hypotension (65+/-12% of initial at a cumulative dose of 3 mg/kg) and bradycardia (80+/-5% of initial at a cumulative dose of 3 mg/kg). At the highest dose, this was characterized by a transient decrease in blood pressure (phase 1) followed by a return to basal level and then a slower decrease in blood pressure (phase 2). Venom also produced a decrease in rate and force of contraction in the rat isolated atria. Interestingly, venom induced a contraction of isolated aortic rings which was blocked by felodipine but not by prazosin, suggesting the contraction is mediated by calcium channel activation. These results suggest that the negative inotropic and chronotropic effects of the venom of N. nomurai may be due to a direct effect on the heart.

  6. JellyWeb: an interactive information system on Scyphozoa, Cubozoa and Staurozoa.

    PubMed

    Martellos, Stefano; Ukosich, Luca; Avian, Massimo

    2016-01-01

    Identification of organisms is traditionally based on the use of "classic" identification keys, normally printed on paper. These keys have several drawbacks: they are mainly based on the systematics, requiring identification of orders, families and genera at first; they are written by experts for other experts, in a specific scientific jargon; they have a "frozen" structure (sequence of theses/antitheses); once published, they cannot be changed or updated without printing a new edition. Due to the use of computers, it is now possible to build new digital identification tools, which: 1) can be produced automatically, if the characters are stored in a database; 2) can be freed from the traditional systematics, giving priority to easy-to-observe characters, incl. those usually uncommon to the classical keys, such as ecology and distribution; 3) can be updated in real time once published on-line; 4) can be available on different media, and on mobile devices. An important feature of these new digital tools is their "collaborative" nature. They can be enriched by the contribution of several researchers, which can cooperate while maintaining rights and property of the resources and data they contribute to the system. JellyWeb, the information system on Scyphozoa, Cubozoa and Staurozoa has been developed in Trieste since 2010. The system was created with the aim of - potentially - becoming a starting point for a wide collaborative effort in developing a user-friendly worldwide digital identification system for jellyfishes.

  7. JellyWeb: an interactive information system on Scyphozoa, Cubozoa and Staurozoa

    PubMed Central

    Martellos, Stefano; Ukosich, Luca; Avian, Massimo

    2016-01-01

    Abstract Identification of organisms is traditionally based on the use of “classic” identification keys, normally printed on paper. These keys have several drawbacks: they are mainly based on the systematics, requiring identification of orders, families and genera at first; they are written by experts for other experts, in a specific scientific jargon; they have a “frozen” structure (sequence of theses/antitheses); once published, they cannot be changed or updated without printing a new edition. Due to the use of computers, it is now possible to build new digital identification tools, which: 1) can be produced automatically, if the characters are stored in a database; 2) can be freed from the traditional systematics, giving priority to easy-to-observe characters, incl. those usually uncommon to the classical keys, such as ecology and distribution; 3) can be updated in real time once published on-line; 4) can be available on different media, and on mobile devices. An important feature of these new digital tools is their “collaborative” nature. They can be enriched by the contribution of several researchers, which can cooperate while maintaining rights and property of the resources and data they contribute to the system. JellyWeb, the information system on Scyphozoa, Cubozoa and Staurozoa has been developed in Trieste since 2010. The system was created with the aim of – potentially – becoming a starting point for a wide collaborative effort in developing a user-friendly worldwide digital identification system for jellyfishes. PMID:26877677

  8. Nematocyst discharge in Pelagia noctiluca (Cnidaria, Scyphozoa) oral arms can be affected by lidocaine, ethanol, ammonia and acetic acid.

    PubMed

    Morabito, Rossana; Marino, Angela; Dossena, Silvia; La Spada, Giuseppa

    2014-06-01

    Nematocyst discharge and concomitant delivery of toxins is triggered to perform both defence and predation strategies in Cnidarians, and may lead to serious local and systemic reactions in humans. Pelagia noctiluca (Cnidaria, Scyphozoa) is a jellyfish particularly abundant in the Strait of Messina (Italy). After accidental contact with this jellyfish, not discharged nematocysts or even fragments of tentacles or oral arms may tightly adhere to the human skin and, following discharge, severely increase pain and the other adverse consequences of the sting. The aim of the present study is to verify if the local anesthetic lidocaine and other compounds, like alcohols, acetic acid and ammonia, known to provide pain relief after jellyfish stings, may also affect in situ discharge of nematocysts. Discharge was induced by a combined physico-chemical stimulation of oral arms by chemosensitizers (such as N-acetylated sugars, aminoacids, proteins and nucleotides), in the presence or absence of 1% lidocaine, 70% ethanol, 5% acetic acid or 20% ammonia, followed by mechanical stimulation by a non-vibrating test probe. The above mentioned compounds failed to induce discharge per se, and dramatically impaired the chemosensitizer-induced discharge response. We therefore suggest that prompt local treatment of the stung epidermis with lidocaine, acetic acid, ethanol and ammonia may provide substantial pain relief and help in reducing possible harmful local and systemic adverse reaction following accidental contact with P. noctiluca specimens. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Heavy metals affect nematocysts discharge response and biological activity of crude venom in the jellyfish Pelagia noctiluca (Cnidaria, Scyphozoa).

    PubMed

    Morabito, Rossana; Dossena, Silvia; La Spada, Giuseppa; Marino, Angela

    2014-01-01

    Pollution of marine ecosystems and, specifically, heavy metals contamination may compromise the physiology of marine animals with events occurring on a cellular and molecular level. The present study focuses on the effect of short-term exposure to heavy metals like Zinc, Cadmium, Cobalt and Lanthanum (2-10 mM) on the homeostasis of Pelagia noctiluca (Cnidaria, Scyphozoa), a jellyfish abundant in the Mediterranean sea. This species possesses stinging organoids, termed nematocysts, whose discharge and concomitant delivery of venom underlie the survival of all Cnidaria. Nematocysts discharge response, elicited by combined chemico-physical stimulation, was verified on excised oral arms exposed to heavy metals for 20 min. In addition, the hemolytic activity of toxins, contained in the crude venom extracted from nematocysts isolated from oral arms, was tested on human erythrocytes, in the presence of heavy metals or their mixture. Treatment with heavy metals significantly inhibited both nematocysts discharge response and hemolytic activity of crude venom, in a dose-dependent manner, not involving oxidative events, that was irreversible in the case of Lanthanum. Our findings show that the homeostasis of Pelagia noctiluca, in terms of nematocysts discharge capability and effectiveness of venom toxins, is dramatically and rapidly compromised by heavy metals and confirm that this jellyfish is eligible as a model for ecotoxicological investigations. © 2014 S. Karger AG, Basel.

  10. First evidence of inbreeding, relatedness and chaotic genetic patchiness in the holoplanktonic jellyfish Pelagia noctiluca (Scyphozoa, Cnidaria).

    PubMed

    Aglieri, Giorgio; Papetti, Chiara; Zane, Lorenzo; Milisenda, Giacomo; Boero, Ferdinando; Piraino, Stefano

    2014-01-01

    Genetic drift and non-random mating seldom influence species with large breeding populations and high dispersal potential, characterized by unstructured gene pool and panmixia at a scale lower than the minimum dispersal range of individuals. In the present study, a set of nine microsatellite markers was developed and used to investigate the spatio-temporal genetic patterns of the holoplanktonic jellyfish Pelagia noctiluca (Scyphozoa) in the Southern Tyrrhenian Sea. Homozygote excess was detected at eight loci, and individuals exhibited intra-population relatedness higher than expected by chance in at least three samples. This result was supported by the presence of siblings in at least 5 out 8 samples, 4 of which contained full-sib in addition to half-sib dyads. Having tested and ruled out alternative explanations as null alleles, our results suggest the influence of reproductive and behavioural features in shaping the genetic structure of P. noctiluca, as outcomes of population genetics analyses pointed out. Indeed, the genetic differentiation among populations was globally small but highlighted: a) a spatial genetic patchiness uncorrelated with distance between sampling locations, and b) a significant genetic heterogeneity between samples collected in the same locations in different years. Therefore, despite its extreme dispersal potential, P. noctiluca does not maintain a single homogenous population, but rather these jellyfish appear to have intra-bloom localized recruitment and/or individual cohesiveness, whereby siblings more likely swarm together as a single group and remain close after spawning events. These findings provide the first evidence of family structures and consequent genetic patchiness in a species with highly dispersive potential throughout its whole life cycle, contributing to understanding the patterns of dispersal and connectivity in marine environments.

  11. First Evidence of Inbreeding, Relatedness and Chaotic Genetic Patchiness in the Holoplanktonic Jellyfish Pelagia noctiluca (Scyphozoa, Cnidaria)

    PubMed Central

    Aglieri, Giorgio; Papetti, Chiara; Zane, Lorenzo; Milisenda, Giacomo; Boero, Ferdinando; Piraino, Stefano

    2014-01-01

    Genetic drift and non-random mating seldom influence species with large breeding populations and high dispersal potential, characterized by unstructured gene pool and panmixia at a scale lower than the minimum dispersal range of individuals. In the present study, a set of nine microsatellite markers was developed and used to investigate the spatio-temporal genetic patterns of the holoplanktonic jellyfish Pelagia noctiluca (Scyphozoa) in the Southern Tyrrhenian Sea. Homozygote excess was detected at eight loci, and individuals exhibited intra-population relatedness higher than expected by chance in at least three samples. This result was supported by the presence of siblings in at least 5 out 8 samples, 4 of which contained full-sib in addition to half-sib dyads. Having tested and ruled out alternative explanations as null alleles, our results suggest the influence of reproductive and behavioural features in shaping the genetic structure of P. noctiluca, as outcomes of population genetics analyses pointed out. Indeed, the genetic differentiation among populations was globally small but highlighted: a) a spatial genetic patchiness uncorrelated with distance between sampling locations, and b) a significant genetic heterogeneity between samples collected in the same locations in different years. Therefore, despite its extreme dispersal potential, P. noctiluca does not maintain a single homogenous population, but rather these jellyfish appear to have intra-bloom localized recruitment and/or individual cohesiveness, whereby siblings more likely swarm together as a single group and remain close after spawning events. These findings provide the first evidence of family structures and consequent genetic patchiness in a species with highly dispersive potential throughout its whole life cycle, contributing to understanding the patterns of dispersal and connectivity in marine environments. PMID:24977703

  12. A new species of Pseudomacrochiron Reddiah, 1969 (Crustacea: Copepoda: Macrochironidae) associated with scyphistomae of the moon jellyfish Aurelia sp. (Cnidaria: Scyphozoa) off Japan.

    PubMed

    Tang, Danny; Yasuda, Akira; Yamada, Satoshi; Nagasawa, Kazuya

    2012-02-01

    A new species of the Macrochironidae Humes & Boxshall, 1996 (Copepoda: Cyclopoida), Pseudomacrochiron aureliae n. sp., is described based on adult specimens extracted from the gastrovacular cavity of the scyphistomae of Aurelia sp. (Cnidaria: Scyphozoa) collected in the Seto Inland Sea and Ise Bay off the coast of Japan. The new species differs from its congeners by having the following combination of characters: a caudal ramus with a length to width ratio of 3.1; an accessory flagellum on caudal setae II, III and VI; three apical setae on the maxillule; only setae I and II on the maxillary basis; two short spines on the female maxilliped claw (endopod); an armature of III, I, 4 on the terminal exopodal segment of leg 3; an armature of I, II, 2 on the terminal endopodal segment of leg 3; an armature of II, I, 4 on the terminal exopodal segment of leg 4; and a short free exopodal segment of leg 5 (length to width ratio of 1.4) armed with a long seta and short spine. P. aureliae n. sp. is the first member of the genus reported from off Japan and from the scyphistomae of its scyphozoan host.

  13. Mitochondrial genome of the moon jelly Aurelia aurita (Cnidaria, Scyphozoa): A linear DNA molecule encoding a putative DNA-dependent DNA polymerase.

    PubMed

    Shao, Zhiyong; Graf, Shannon; Chaga, Oleg Y; Lavrov, Dennis V

    2006-10-15

    The 16,937-nuceotide sequence of the linear mitochondrial DNA (mt-DNA) molecule of the moon jelly Aurelia aurita (Cnidaria, Scyphozoa) - the first mtDNA sequence from the class Scypozoa and the first sequence of a linear mtDNA from Metazoa - has been determined. This sequence contains genes for 13 energy pathway proteins, small and large subunit rRNAs, and methionine and tryptophan tRNAs. In addition, two open reading frames of 324 and 969 base pairs in length have been found. The deduced amino-acid sequence of one of them, ORF969, displays extensive sequence similarity with the polymerase [but not the exonuclease] domain of family B DNA polymerases, and this ORF has been tentatively identified as dnab. This is the first report of dnab in animal mtDNA. The genes in A. aurita mtDNA are arranged in two clusters with opposite transcriptional polarities; transcription proceeding toward the ends of the molecule. The determined sequences at the ends of the molecule are nearly identical but inverted and lack any obvious potential secondary structures or telomere-like repeat elements. The acquisition of mitochondrial genomic data for the second class of Cnidaria allows us to reconstruct characteristic features of mitochondrial evolution in this animal phylum.

  14. Dynamic Model for Life History of Scyphozoa.

    PubMed

    Xie, Congbo; Fan, Meng; Wang, Xin; Chen, Ming

    2015-01-01

    A two-state life history model governed by ODEs is formulated to elucidate the population dynamics of jellyfish and to illuminate the triggering mechanism of its blooms. The polyp-medusa model admits trichotomous global dynamic scenarios: extinction, polyps survival only, and both survival. The population dynamics sensitively depend on several biotic and abiotic limiting factors such as substrate, temperature, and predation. The combination of temperature increase, substrate expansion, and predator diminishment acts synergistically to create a habitat that is more favorable for jellyfishes. Reducing artificial marine constructions, aiding predator populations, and directly controlling the jellyfish population would help to manage the jellyfish blooms. The theoretical analyses and numerical experiments yield several insights into the nature underlying the model and shed some new light on the general control strategy for jellyfish.

  15. Dynamic Model for Life History of Scyphozoa

    PubMed Central

    Xie, Congbo; Fan, Meng; Wang, Xin; Chen, Ming

    2015-01-01

    A two-state life history model governed by ODEs is formulated to elucidate the population dynamics of jellyfish and to illuminate the triggering mechanism of its blooms. The polyp-medusa model admits trichotomous global dynamic scenarios: extinction, polyps survival only, and both survival. The population dynamics sensitively depend on several biotic and abiotic limiting factors such as substrate, temperature, and predation. The combination of temperature increase, substrate expansion, and predator diminishment acts synergistically to create a habitat that is more favorable for jellyfishes. Reducing artificial marine constructions, aiding predator populations, and directly controlling the jellyfish population would help to manage the jellyfish blooms. The theoretical analyses and numerical experiments yield several insights into the nature underlying the model and shed some new light on the general control strategy for jellyfish. PMID:26114642

  16. Life Cycle Reversal in Aurelia sp.1 (Cnidaria, Scyphozoa).

    PubMed

    He, Jinru; Zheng, Lianming; Zhang, Wenjing; Lin, Yuanshao

    2015-01-01

    The genus Aurelia is one of the major contributors to jellyfish blooms in coastal waters, possibly due in part to hydroclimatic and anthropogenic causes, as well as their highly adaptive reproductive traits. Despite the wide plasticity of cnidarian life cycles, especially those recognized in certain Hydroza species, the known modifications of Aurelia life history were mostly restricted to its polyp stage. In this study, we document the formation of polyps directly from the ectoderm of degenerating juvenile medusae, cell masses from medusa tissue fragments, and subumbrella of living medusae. This is the first evidence for back-transformation of sexually mature medusae into polyps in Aurelia sp.1. The resulting reconstruction of the schematic life cycle of Aurelia reveals the underestimated potential of life cycle reversal in scyphozoan medusae, with possible implications for biological and ecological studies.

  17. Complete mitochondrial genome of the jellyfish, Chrysaora quinquecirrha (Cnidaria, Scyphozoa).

    PubMed

    Hwang, Dae-Sik; Park, Eunji; Won, Yong-Jin; Lee, Woo-Jin; Shin, Kyoungsoon; Lee, Jae-Seong

    2014-02-01

    We sequenced 16,775 bp of the linear mitochondrial DNA of the jellyfish Chrysaora quinquecirrha and characterized them. C. quinquecirrha has 13 protein-coding genes (PCGs), 16S rRNA and 12S rRNA with 3 tRNAs (tRNA-Leu, tRNA-Ser(TGA), tRNA-Met) as shown in Aurelia sp. nov. Both have another two PCGs such as helicase and orf363 with telomeres at both ends. The PCGs of C. quinquecirrha shows anti-G bias on 2nd and 3rd positions of PCGs as well as anti-C bias on 1st and 3rd positions of PCGs.

  18. Life Cycle Reversal in Aurelia sp.1 (Cnidaria, Scyphozoa)

    PubMed Central

    He, Jinru; Zheng, Lianming; Zhang, Wenjing; Lin, Yuanshao

    2015-01-01

    The genus Aurelia is one of the major contributors to jellyfish blooms in coastal waters, possibly due in part to hydroclimatic and anthropogenic causes, as well as their highly adaptive reproductive traits. Despite the wide plasticity of cnidarian life cycles, especially those recognized in certain Hydroza species, the known modifications of Aurelia life history were mostly restricted to its polyp stage. In this study, we document the formation of polyps directly from the ectoderm of degenerating juvenile medusae, cell masses from medusa tissue fragments, and subumbrella of living medusae. This is the first evidence for back-transformation of sexually mature medusae into polyps in Aurelia sp.1. The resulting reconstruction of the schematic life cycle of Aurelia reveals the underestimated potential of life cycle reversal in scyphozoan medusae, with possible implications for biological and ecological studies. PMID:26690755

  19. Tentacle Transcriptome and Venom Proteome of the Pacific Sea Nettle, Chrysaora fuscescens (Cnidaria: Scyphozoa)

    PubMed Central

    Ponce, Dalia; Brinkman, Diane L.; Potriquet, Jeremy; Mulvenna, Jason

    2016-01-01

    Jellyfish venoms are rich sources of toxins designed to capture prey or deter predators, but they can also elicit harmful effects in humans. In this study, an integrated transcriptomic and proteomic approach was used to identify putative toxins and their potential role in the venom of the scyphozoan jellyfish Chrysaora fuscescens. A de novo tentacle transcriptome, containing more than 23,000 contigs, was constructed and used in proteomic analysis of C. fuscescens venom to identify potential toxins. From a total of 163 proteins identified in the venom proteome, 27 were classified as putative toxins and grouped into six protein families: proteinases, venom allergens, C-type lectins, pore-forming toxins, glycoside hydrolases and enzyme inhibitors. Other putative toxins identified in the transcriptome, but not the proteome, included additional proteinases as well as lipases and deoxyribonucleases. Sequence analysis also revealed the presence of ShKT domains in two putative venom proteins from the proteome and an additional 15 from the transcriptome, suggesting potential ion channel blockade or modulatory activities. Comparison of these potential toxins to those from other cnidarians provided insight into their possible roles in C. fuscescens venom and an overview of the diversity of potential toxin families in cnidarian venoms. PMID:27058558

  20. Pelagia noctiluca (Scyphozoa) Crude Venom Injection Elicits Oxidative Stress and Inflammatory Response in Rats

    PubMed Central

    Bruschetta, Giuseppe; Impellizzeri, Daniela; Morabito, Rossana; Marino, Angela; Ahmad, Akbar; Spanò, Nunziacarla; La Spada, Giuseppa; Cuzzocrea, Salvatore; Esposito, Emanuela

    2014-01-01

    Cnidarian toxins represent a rich source of biologically active compounds. Since they may act via oxidative stress events, the aim of the present study was to verify whether crude venom, extracted from the jellyfish Pelagia noctiluca, elicits inflammation and oxidative stress processes, known to be mediated by Reactive Oxygen Species (ROS) production, in rats. In a first set of experiments, the animals were injected with crude venom (at three different doses 6, 30 and 60 µg/kg, suspended in saline solution, i.v.) to test the mortality and possible blood pressure changes. In a second set of experiments, to confirm that Pelagia noctiluca crude venom enhances ROS formation and may contribute to the pathophysiology of inflammation, crude venom-injected animals (30 µg/kg) were also treated with tempol, a powerful antioxidant (100 mg/kg i.p., 30 and 60 min after crude venom). Administration of tempol after crude venom challenge, caused a significant reduction of each parameter related to inflammation. The potential effect of Pelagia noctiluca crude venom in the systemic inflammation process has been here demonstrated, adding novel information about its biological activity. PMID:24727391

  1. Characterization and neutralization of Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom using polyclonal antibody.

    PubMed

    Kang, Changkeun; Han, Dae-Yong; Park, Kwang-Il; Pyo, Min-Jung; Heo, Yunwi; Lee, Hyunkyoung; Kim, Gon Sup; Kim, Euikyung

    2014-08-01

    Jellyfish stings have often caused serious health concerns for sea bathers especially in tropical waters. In the coastal areas of Korea, China and Japan, the blooming and stinging accidents of poisonous jellyfish species have recently increased, including Nemopilema nomurai. We have generated a polyclonal antibody against N. nomurai jellyfish venom (NnV) by the immunization of white rabbits with NnV antigen. In the present study, the antibody has been characterized for its neutralizing effect against NnV. At first, the presence of NnV polyclonal antibody has been confirmed from the immunized rabbit serum by Enzyme linked immunosorbent assay (ELISA). Then, the neutralizing activities of the polyclonal antibody have been investigated using cell-based toxicity test, hemolysis assay, and mice lethality test. When the polyclonal antibody was preincubated with NnV, it shows a high effectiveness in neutralizing the NnV toxicities in a concentration-dependent manner. Moreover, we explored proteomic analyses using 2-D SDS-PAGE and MALDI-TOF mass spectrometry to illustrate the molecular identities of the jellyfish venom. From this, 18 different protein families have been identified as jellyfish venom-derived proteins; the main findings of which are matrix metalloproteinase-14, astacin-like metalloprotease toxin 3 precursor. It is expected that the present results would have contributed to our understandings of the envenomation by N. nomurai, their treatment and some valuable knowledge on the pathological processes of the jellyfish stinging.

  2. Complete mitochondrial genome of the moon jellyfish, Aurelia sp. nov. (Cnidaria, Scyphozoa).

    PubMed

    Hwang, Dae-Sik; Park, Eunji; Won, Yong-Jin; Lee, Jae-Seong

    2014-02-01

    We sequenced 16,971 bp of the linear mitochondrial DNA of the moon jellyfish Aurelia sp. nov. and characterized it by comparing with Aurelia aurita. They had 13 protein-coding genes (PCGs), 16S rRNA and 12S rRNA with three tRNAs (tRNA-Leu, tRNA-Ser(TGA), tRNA-Met). Both have another two PCGs, orf969 and orf324 with telomeres at both ends. After comparison of Aurelia sp. nov. with Aurelia aurita, we found low-protein similarity of orf969 (59%) and orf324 (75%), respectively, while the other 13 PCGs showed 80% to 98% protein similarities.

  3. Pelagia benovici sp. nov. (Cnidaria, Scyphozoa): a new jellyfish in the Mediterranean Sea.

    PubMed

    Piraino, Stefano; Aglieri, Giorgio; Martell, Luis; Mazzoldi, Carlotta; Melli, Valentina; Milisenda, Giacomo; Scorrano, Simonetta; Boero, Ferdinando

    2014-05-07

    A bloom of an unknown semaestome jellyfish species was recorded in the North Adriatic Sea from September 2013 to early 2014. Morphological analysis of several specimens showed distinct differences from other known semaestome species in the Mediterranean Sea and unquestionably identified them as belonging to a new pelagiid species within genus Pelagia. The new species is morphologically distinct from P. noctiluca, currently the only recognized valid species in the genus, and from other doubtful Pelagia species recorded from other areas of the world. Molecular analyses of mitochondrial cytochrome c oxidase subunit I (COI) and nuclear 28S ribosomal DNA genes corroborate its specific distinction from P. noctiluca and other pelagiid taxa, supporting the monophyly of Pelagiidae. Thus, we describe Pelagia benovici sp. nov. Piraino, Aglieri, Scorrano & Boero.

  4. Tentacle Transcriptome and Venom Proteome of the Pacific Sea Nettle, Chrysaora fuscescens (Cnidaria: Scyphozoa).

    PubMed

    Ponce, Dalia; Brinkman, Diane L; Potriquet, Jeremy; Mulvenna, Jason

    2016-04-05

    Jellyfish venoms are rich sources of toxins designed to capture prey or deter predators, but they can also elicit harmful effects in humans. In this study, an integrated transcriptomic and proteomic approach was used to identify putative toxins and their potential role in the venom of the scyphozoan jellyfish Chrysaora fuscescens. A de novo tentacle transcriptome, containing more than 23,000 contigs, was constructed and used in proteomic analysis of C. fuscescens venom to identify potential toxins. From a total of 163 proteins identified in the venom proteome, 27 were classified as putative toxins and grouped into six protein families: proteinases, venom allergens, C-type lectins, pore-forming toxins, glycoside hydrolases and enzyme inhibitors. Other putative toxins identified in the transcriptome, but not the proteome, included additional proteinases as well as lipases and deoxyribonucleases. Sequence analysis also revealed the presence of ShKT domains in two putative venom proteins from the proteome and an additional 15 from the transcriptome, suggesting potential ion channel blockade or modulatory activities. Comparison of these potential toxins to those from other cnidarians provided insight into their possible roles in C. fuscescens venom and an overview of the diversity of potential toxin families in cnidarian venoms.

  5. Cytotoxicity and hemolytic activity of jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) venom.

    PubMed

    Kang, Changkeun; Munawir, Al; Cha, Mijin; Sohn, Eun-Tae; Lee, Hyunkyoung; Kim, Jong-Shu; Yoon, Won Duk; Lim, Donghyun; Kim, Euikyung

    2009-07-01

    The recent bloom of a giant jellyfish Nemopilema nomurai has caused a danger to sea bathers and fishery damages in the waters of China, Korea, and Japan. The present study investigated the cytotoxic and hemolytic activities of crude venom extract of N. nomurai using a number of in vitro assays. The jellyfish venom showed a much higher cytotoxic activity in H9C2 heart myoblast than in C2C12 skeletal myoblast (LC(50)=2 microg/mL vs. 12 microg/mL, respectively), suggesting its possible in vivo selective toxicity on cardiac tissue. This result is consistent with our previous finding that cardiovascular function is a target of the venom. In order to determine the stability of N. nomurai venom, its cytotoxicity was examined under the various temperature and pH conditions. The activity was relatively well retained at low environmental temperature (or=60 degrees C). In pH stability test, the venom has abruptly lost its activity at low pH environment (pH

  6. The Bright Side of Gelatinous Blooms: Nutraceutical Value and Antioxidant Properties of Three Mediterranean Jellyfish (Scyphozoa).

    PubMed

    Leone, Antonella; Lecci, Raffaella Marina; Durante, Miriana; Meli, Federica; Piraino, Stefano

    2015-07-29

    Jellyfish are recorded with increasing frequency and magnitude in many coastal areas and several species display biological features comparable to the most popular Asiatic edible jellyfish. The biochemical and antioxidant properties of wild gelatinous biomasses, in terms of nutritional and nutraceutical values, are still largely unexplored. In this paper, three of the most abundant and commonly recorded jellyfish species (Aurelia sp.1, Cotylorhiza tuberculata and Rhizostoma pulmo) in the Mediterranean Sea were subject to investigation. A sequential enzymatic hydrolysis of jellyfish proteins was set up by pepsin and collagenase treatments of jellyfish samples after aqueous or hydroalcoholic protein extraction. The content and composition of proteins, amino acids, phenolics, and fatty acids of the three species were recorded and compared. Protein content (mainly represented by collagen) up to 40% of jellyfish dry weight were found in two of the three jellyfish species (C. tuberculata and R. pulmo), whereas the presence of ω-3 and ω-6 polyunsaturated fatty acids (PUFAs) was significantly higher in the zooxanthellate jellyfish C. tuberculata only. Remarkable antioxidant ability was also recorded from both proteinaceous and non proteinaceous extracts and the hydrolyzed protein fractions in all the three species. The abundance of collagen, peptides and other bioactive molecules make these Mediterranean gelatinous biomasses a largely untapped source of natural compounds of nutraceutical, cosmeceutical and pharmacological interest.

  7. Trace element accumulation in Cassiopea sp. (Scyphozoa) from urban marine environments in Australia.

    PubMed

    Templeman, Michelle A; Kingsford, Michael J

    2010-03-01

    Jellyfishes are robust, short-lived animals, tolerant to a wide range of environmental conditions and pollutants. The benthic jellyfish, Cassiopea sp. was collected from five locations along the north and eastern coast of Australia and analysed for trace elements to determine if this species has potential as a marine biomonitor. Both the oral arm and bell tissues readily accumulated aluminium, arsenic, barium, cadmium, chromium, copper, iron, manganese and zinc above ambient seawater levels. In contrast, lithium appeared to be actively regulated within the tissues while calcium, magnesium and strontium reflected the ambient environment. The multi-element signatures showed spatial variation, reflecting the geographical separations between locations, with locations closer together showing more similar elemental patterns. The combination of bioaccumulative capacity, life history traits and biophysical aspects indicate that this species has high potential as a biomonitor in coastal marine systems.

  8. Lack of genetic structure in the jellyfish Pelagia noctiluca (Cnidaria: Scyphozoa: Semaeostomeae) across European seas.

    PubMed

    Stopar, Katja; Ramsak, Andreja; Trontelj, Peter; Malej, Alenka

    2010-10-01

    The genetic structure of the holopelagic scyphozoan Pelagia noctiluca was inferred based on the study of 144 adult medusae. The areas of study were five geographic regions in two European seas (Eastern Atlantic and Mediterranean Sea). A 655-bp sequence of mitochondrial cytochrome c oxidase subunit I (COI), and a 645-bp sequence of two nuclear internal transcribed spacers (ITS1 and ITS2) were analyzed. The protein coding COI gene showed a higher level of divergence than the combined nuclear ITS fragment (haplotype diversity 0.962 vs. 0.723, nucleotide diversity 1.16% vs. 0.31%). Phylogeographic analysis on COI gene revealed two clades, the larger consisting of specimens from all sampling sites, and the smaller mostly formed of specimens from the Mediterranean Sea. Haplotype diversity was very high throughout the sampled area, and within sample diversity was higher than diversity among geographical regions. No strongly supported genetically or geographically distinct groups of P. noctiluca were found. The results - long distance dispersal, insignificant F(ST) values, lack of isolation by distance - pointed toward an admixture among Mediterranean and East Atlantic populations. Copyright 2010 Elsevier Inc. All rights reserved.

  9. The occurrence of Ophiocnemis marmorata (Echinodermata: Ophiuroidea) associated with the rhizostome medusa Rhopilema hispidum (Cnidaria: Scyphozoa)

    NASA Astrophysics Data System (ADS)

    Kanagaraj, Govindan; Kumar, Pithchai Sampath; Morandini, André C.

    2008-11-01

    The association of scyphomedusae with invertebrates has been long known in the literature; especially with hyperiids amphipods. The association of echinoderms with jellyfish is not common and rarely recorded. We reported the association of the ophiuroid Ophiocnemis marmorata with the rhizostome scyphomedusa Rhopilema hispidum collected in Vellar estuary (on the southeast coast of India). O. marmorata is supposed to be a filter feeding ophiuroid, quite common in soft bottom of shallow waters. The brittle stars possibly seek for food supply, shelter and protection through the association.

  10. The Bright Side of Gelatinous Blooms: Nutraceutical Value and Antioxidant Properties of Three Mediterranean Jellyfish (Scyphozoa)

    PubMed Central

    Leone, Antonella; Lecci, Raffaella Marina; Durante, Miriana; Meli, Federica; Piraino, Stefano

    2015-01-01

    Jellyfish are recorded with increasing frequency and magnitude in many coastal areas and several species display biological features comparable to the most popular Asiatic edible jellyfish. The biochemical and antioxidant properties of wild gelatinous biomasses, in terms of nutritional and nutraceutical values, are still largely unexplored. In this paper, three of the most abundant and commonly recorded jellyfish species (Aurelia sp.1, Cotylorhiza tuberculata and Rhizostoma pulmo) in the Mediterranean Sea were subject to investigation. A sequential enzymatic hydrolysis of jellyfish proteins was set up by pepsin and collagenase treatments of jellyfish samples after aqueous or hydroalcoholic protein extraction. The content and composition of proteins, amino acids, phenolics, and fatty acids of the three species were recorded and compared. Protein content (mainly represented by collagen) up to 40% of jellyfish dry weight were found in two of the three jellyfish species (C. tuberculata and R. pulmo), whereas the presence of ω-3 and ω-6 polyunsaturated fatty acids (PUFAs) was significantly higher in the zooxanthellate jellyfish C. tuberculata only. Remarkable antioxidant ability was also recorded from both proteinaceous and non proteinaceous extracts and the hydrolyzed protein fractions in all the three species. The abundance of collagen, peptides and other bioactive molecules make these Mediterranean gelatinous biomasses a largely untapped source of natural compounds of nutraceutical, cosmeceutical and pharmacological interest. PMID:26230703

  11. On natural metamorphosis inducers of the cnidarians Hydractinia echinata (Hydrozoa) and Aurelia aurita (Scyphozoa)

    NASA Astrophysics Data System (ADS)

    Kroiher, M.; Berking, S.

    1999-11-01

    Hydractinia echinata and Aurelia aurita produce motile larvae which undergo metamorphosis to sessile polyps when induced by external cues. The polyps are found at restricted sites, A. aurita predominantly on rocks close to the shore, H. echinata on shells inhabited by hermit crabs. It has been argued that the differential distribution of the polyps in their natural environment largely reflects the distribution of the natural metamorphosis-inducing cues. In the case of H. echinata, bacteria of the genus Alteromonas were argued to meet these conditions. We found that almost all substrates collected in the littoral to induce metamorphosis in H. echinata, and several bacterial strains isolated from the sea, including the common E. coli, induce metamorphosis efficiently. In A. aurita metamorphosis may be induced by the water-air interface, whereby metamorphosis precedes (final) settlement.

  12. Localization of digestion activities in polyps of Nausithoe planulophora and Thecoscyphus zibrowii (Coronatae, Scyphozoa, Cnidaria)

    NASA Astrophysics Data System (ADS)

    Bumann, Dirk; Jarms, Gerhard

    1998-02-01

    Coronate polyps are unique among cnidarians in having a complete peridermal tube, a ring canal, and four radial canals or pores at their oral region. Moreover, most of these species possess tooth whorls that narrow the gastric cavity considerably. Using fluorescence-labeled prey, it was demonstrated that the ring canal is not involved in digestion or redistribution of nutrients but possibly serves as a hydrostatic flex point for the fast retraction of the tentacle crown into the exoskeleton. The tooth whorls considerably affect the localization of digestion activities by blocking the passage of large prey fragments. Hence, endocytosis in a coronate species with tooth whorls occurred around the uppermost tooth whorl whereas, in a species lacking tooth whorls endocytosis occurred at the basal end. To meet the high nutrient demands of the basal region, nutrients must be redistributed in the species with tooth whorls. The extra energy required for this redistribution could be an important disadvantage of tooth whorls.

  13. Bacterially induced stolon settlement in the scyphopolyp of Aurelia aurita (Cnidaria, Scyphozoa)

    NASA Astrophysics Data System (ADS)

    Schmahl, G.

    1985-03-01

    Unsettled stoloniferous scyphopolyps of Aurelia aurita Lamarck were offered different substrates for settlement under defined conditions. On addition of different biogenic and abiotic substrates, a pure strain of bacteria, a species of Micrococcaceae, was observed to trigger the settlement of the stolon. The settlement reaction only takes place following direct contact with the bacteria; sterile filtrated culture medium of the same bacterial strain was not able to induce settlement. The bacteria were found to be effective on stolon settlement during the logarithmic growth phase, but not during the stationary phase.

  14. Effects of temperature and salinity on the asexual reproduction of Nemopilema nomurai (Scyphozoa: Rhizostomeae)

    NASA Astrophysics Data System (ADS)

    Lee, Hye Eun; Han, Chang Hoon; Kim, ByeongHo; Yoon, Won Duk

    2017-07-01

    Asexual reproduction of polyps of Nemopilema nomurai, of which massive blooms have occurred in Korean waters every summer since 2003, were tested under 20 combinations of temperature (10, 15, 20, and 25°C) and salinity (12, 17, 22, 27, and 32 psu). Production of podocysts increased with increasing temperature (20 and 25°C), while strobilaton and ephyral liberation occurred at low temperatures (10 and 15°C). Temperature also affected the initiation of ephyral liberation (approximately 25 days at 15°C, and 50 days at 10 and 20°C, respectively). The number of podocysts was only significantly different between 27 and 32 psu, and salinity had no significant effect on the excystment of podocysts, ephyral liberlation, showing N. nomurai is euryhaline. These results demonstrated that temperature is an important factor on both the podocysts production and ephyrae liberation, possibly explaining early spring liberation of ephyrae and continuous introduction of medusae into Korean coastal waters through summer to fall.

  15. Metal bioaccumulation pattern by Cotylorhiza tuberculata (Cnidaria, Scyphozoa) in the Mar Menor coastal lagoon (SE Spain).

    PubMed

    Muñoz-Vera, Ana; García, Gregorio; García-Sánchez, Antonio

    2015-12-01

    Coastal lagoons are ecosystems highly vulnerable to human impacts because of their situation between terrestrial and marine environment. Mar Menor coastal lagoon is one of the largest lagoons of the Mediterranean Sea, placed in SE Spain and subjected to major human impacts, in particular the mining of metal sulphides. As a consequence, metal concentration in water column and sediments of this ecosystem is usually higher than in other areas. For monitoring ecosystem health, the present study has assessed the ability of Cotylorhiza tuberculata for bioaccumulating metals from sea water. Up to 65 individuals were sampled at 8 different sampling stations during the summer of 2012. Although the concentration values for different elements considered were moderate (Pb: 0.04-29.50 ppm, Zn: 2.27-93.44 ppm, Cd: 0-0.67 ppm, As: 0.56-130.31 ppm) by dry weight of the jellyfish tissues (bell and oral arms combined), bioconcentration levels in relation to seawater metal concentration were extremely high. In any case, the use or disposal of these organisms should consider their metal content because of their potential environmental and health implications.

  16. Crude venom from nematocysts of Pelagia noctiluca (Cnidaria: Scyphozoa) elicits a sodium conductance in the plasma membrane of mammalian cells

    PubMed Central

    Morabito, Rossana; Costa, Roberta; Rizzo, Valentina; Remigante, Alessia; Nofziger, Charity; La Spada, Giuseppa; Marino, Angela; Paulmichl, Markus; Dossena, Silvia

    2017-01-01

    Cnidarians may negatively impact human activities and public health but concomitantly their venom represents a rich source of bioactive substances. Pelagia noctiluca is the most venomous and abundant jellyfish of the Mediterranean Sea and possesses a venom with hemolytic and cytolytic activity for which the mechanism is largely unknown. Here we show that exposure of mammalian cells to crude venom from the nematocysts of P. noctiluca profoundly alters the ion conductance of the plasma membrane, therefore affecting homeostatic functions such as the regulation and maintenance of cellular volume. Venom-treated cells exhibited a large, inwardly rectifying current mainly due to permeation of Na+ and Cl−, sensitive to amiloride and completely abrogated following harsh thermal treatment of crude venom extract. Curiously, the plasma membrane conductance of Ca2+ and K+ was not affected. Current-inducing activity was also observed following delivery of venom to the cytosolic side of the plasma membrane, consistent with a pore-forming mechanism. Venom-induced NaCl influx followed by water and consequent cell swelling most likely underlie the hemolytic and cytolytic activity of P. noctiluca venom. The present study underscores unique properties of P. noctiluca venom and provides essential information for a possible use of its active compounds and treatment of envenomation. PMID:28112211

  17. [Lipid variation in oocytes of the jellyfish Stomolophus meleagris (Scyphozoa: Rhizostomeae) from Las Guasimas Lagoon, Mexico, during gonadal development].

    PubMed

    Carvalho-Saucedo, Liliana; García-Domínguez, Federico; Rodríguez-Jaramillo, Carmen; López-Martínez, Juana

    2010-03-01

    The jellyfish Stomolophus meleagris has potential for commercial exploitation but there is little information on their reproductive biology. This paper seeks to evaluate some biochemical and demographic characteristics of the species. Samples were taken monthly during 2005 and 2006. Jellyfish collected in 2005 were used to describe the characteristics and quantity of oocyte triglycerides and phospholipids with the Sudan black technique, and to ascertain the degree of gonadal development and sex ratio by the hematoxylin-eosin technique. The 2006 jellyfish were used to determine the size at first maturity and protein and total lipids contents. Four stages of development in both sexes were determined, with a continuous gamete development. The highest percentage of mature organisms was recorded in April. The proportion of sexes was 0.7:1.3. We found higher concentrations of triglycerides than phospholipids in the cytoplasm. There was a positive correlation between triglycerides and the diameter of the oocyte. The size at first maturity for both sexes was 105 mm. The highest protein and lipids contents were obtained in April and March respectively.

  18. Physiological and chemical analysis of neurotransmitter candidates at a fast excitatory synapse in the jellyfish Cyanea capillata (Cnidaria, Scyphozoa).

    PubMed

    Anderson, Peter A V; Trapido-Rosenthal, H G

    2009-12-01

    Motor nerve net (MNN) neurons in the jellyfish Cyanea capillata communicate with one another by way of fast, bidirectional excitatory chemical synapses. As is the case with almost all identified chemical synapses in cnidarians, the identity of the neurotransmitter at these synapses is unclear. MNN neurons are large enough for stable intracellular recordings. This, together with the fact that they can be exposed, providing unlimited access to them and to their synapses, prompted a study of the action of a variety of neurotransmitter candidates, including those typically associated with fast synapses in higher animals. Only the amino acids taurine and beta-alanine produced physiological responses consistent with those of the normal EPSP in these cells. Moreover, chemical analysis revealed that both taurine and beta-alanine are present in the neurons and released by depolarization. These various findings strongly suggest that either or both of these amino acids, or a closely related compound is the neurotransmitter at the fast chemical synapses between MNN neurons.

  19. Fine structure, histochemistry, and morphogenesis during excystment of the podocysts of the giant jellyfish Nemopilema nomurai (Scyphozoa, Rhizostomeae).

    PubMed

    Ikeda, Hideki; Ohtsu, Kohzoh; Uye, Shin-Ichi

    2011-12-01

    Production of podocysts is the exclusive form of asexual reproduction by polyps of the giant jellyfish Nemopilema nomurai, which has been recurrently blooming in the East Asian seas in the last decade. Podocycts consist of a dome-shaped chitinous capsule with laminated structure that encapsulates a mass of cyst cells filled with granules containing nutrient reserves such as proteins, carbohydrates, and lipids. Mitochondria, rough endoplasmic reticulum, and Golgi complexes are scarce in the cytoplasm of these cells, and the staining reaction for RNA is weak, indicating very low metabolic activity. Podocysts are capable of dormancy for at least 5 years without significant change of internal structure or nutrient reserves. Integrated information about spontaneous and artificially induced metamorphosis suggests that the following processes occur during excystment: (1) nematocyst formation in the internal cell mass, (2) stratification of the cell mass into endoderm and ectoderm, (3) extrusion of the cell mass through a gradual opening of the capsule, (4) formation of primordial polyp mouth and tentacles, and (5) metamorphosis to a polyp. We morphologically confirmed that N. nomurai podocysts have the capacity for long-term dormancy, an ability that should contribute to the periodic nature of the massive blooms of medusae of this species.

  20. Patterns of trace element bioaccumulation in jellyfish Rhizostoma pulmo (Cnidaria, Scyphozoa) in a Mediterranean coastal lagoon from SE Spain.

    PubMed

    Muñoz-Vera, Ana; Peñas Castejón, Jose Matías; García, Gregorio

    2016-09-15

    The effects of an abandoned mining area, exploited for centuries in the mining district of Cartagena-La Union, result in a continuous supply of heavy metals into the Mar Menor coastal lagoon after rain episodes. As a consequence, concentration of trace elements in water column and sediments of this ecosystem is usually higher than in other areas. For monitoring ecosystem health, this study assessed the ability of Rhizostoma pulmo to bioaccumulate trace elements. A total of 57 individuals were sampled at eight different sampling stations during the summer of 2012. Although the concentrations of different analyzed elements (Al, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, Sn, and Pb) were moderate, bioconcentration levels in relation to seawater metal concentration were extremely high. In any case, the use or disposal of these organisms should consider their metal content, because of their potential environmental and health implications.

  1. Reproduction of the giant jellyfish, Nemopilema nomurai (Scyphozoa: Rhizostomeae), in 2006-2008 as peripherally-transported populations

    NASA Astrophysics Data System (ADS)

    Iguchi, Naoki; Lee, Hye Eun; Yoon, Won Duk; Kim, Suam

    2010-06-01

    This study investigated the sexual maturation process, release of spermatozoa or eggs and oocyte diameter of the rhizostomid medusae Nemopilema nomurai using samples collected from August 2006 to June 2008 from the waters around Korea and Japan, including peripheral areas outside the species’ usual habitat. Immature medusae were observed from June to October only in the western sector of the study area. The onset of spermatozoa and egg release occurred in September and October, respectively, and peaked in December and January. Medusae migrated eastward from source areas with the Tsushima Warm Current, where they formed gametes and spawned. Peak position and maximum oocyte diameter increased as the gonads developed according to the size-frequency distribution of oocytes. No fertilized eggs or embryos were found in the gonads. The correlation was analyzed with bell diameter, maximum oocyte diameter, sampling date, surface water temperature and gonad color to estimate which environmental factors and maturation indices were related to the maturation stage of females. Maturation stage correlated well with maximum oocyte diameter, which correlated negatively with surface water temperature. There was no significant correlation between bell diameter and maturation stage. Therefore, bell diameter was inappropriate for determining maturation index. Sex could not be distinguished clearly by gonad color. However, light pink gonads were more prevalent in males and various deep colors such as orange and brown were more frequent in female medusae.

  2. Environmental control of asexual reproduction and somatic growth of Aurelia spp. (Cnidaria, Scyphozoa) polyps from the Adriatic Sea.

    PubMed

    Hubot, Nathan; Lucas, Cathy H; Piraino, Stefano

    2017-01-01

    Polyps of two moon jellyfish species, Aurelia coerulea and A. relicta, from two Adriatic Sea coastal habitats were incubated under multiple combinations of temperature (14, 21°C), salinity (24, 37 ppt) and food regime (9.3, 18.6, 27.9 μg C ind-1 week-1) to comparatively assess how these factors may influence major asexual reproduction processes in the two species. Both species exhibited a shared pattern of budding mode (Directly Budded Polyps: DBP; Stolonal Budded Polyps: SBP), with DBP favoured under low food supply (9.3 μg C ind -1 week-1) and low temperature (14°C), and SBP dominant under high temperature (21°C). However, A. coerulea showed an overall higher productivity than A. relicta, in terms of budding and podocyst production rates. Further, A. coerulea exhibited a wide physiological plasticity across different temperatures and salinities as typical adaptation to ecological features of transitional coastal habitats. This may support the hypothesis that the invasion of A. coerulea across coastal habitats worldwide has been driven by shellfish aquaculture, with scyphistoma polyps and resting stages commonly found on bivalve shells. On the contrary, A. relicta appears to be strongly stenovalent, with cold, marine environmental optimal preferences (salinity 37 ppt, T ranging 14-19°C), corroborating the hypothesis of endemicity within the highly peculiar habitat of the Mljet lake. By exposing A. relicta polyps to slightly higher temperature (21°C), a previously unknown developmental mode was observed, by the sessile polyp regressing into a dispersive, temporarily unattached and tentacle-less, non-feeding stage. This may allow A. relicta polyps to escape climatic anomalies associated to warming of surface layers and deepening of isotherms, by moving into deeper, colder layers. Overall, investigations on species-specific eco-physiological and ontogenetic potentials of polyp stages may contribute to clarify the biogeographic distribution of jellyfish and the phylogenetic relationships among evolutionary related sister clades.

  3. Crude venom from nematocysts of Pelagia noctiluca (Cnidaria: Scyphozoa) elicits a sodium conductance in the plasma membrane of mammalian cells

    NASA Astrophysics Data System (ADS)

    Morabito, Rossana; Costa, Roberta; Rizzo, Valentina; Remigante, Alessia; Nofziger, Charity; La Spada, Giuseppa; Marino, Angela; Paulmichl, Markus; Dossena, Silvia

    2017-01-01

    Cnidarians may negatively impact human activities and public health but concomitantly their venom represents a rich source of bioactive substances. Pelagia noctiluca is the most venomous and abundant jellyfish of the Mediterranean Sea and possesses a venom with hemolytic and cytolytic activity for which the mechanism is largely unknown. Here we show that exposure of mammalian cells to crude venom from the nematocysts of P. noctiluca profoundly alters the ion conductance of the plasma membrane, therefore affecting homeostatic functions such as the regulation and maintenance of cellular volume. Venom-treated cells exhibited a large, inwardly rectifying current mainly due to permeation of Na+ and Cl-, sensitive to amiloride and completely abrogated following harsh thermal treatment of crude venom extract. Curiously, the plasma membrane conductance of Ca2+ and K+ was not affected. Current-inducing activity was also observed following delivery of venom to the cytosolic side of the plasma membrane, consistent with a pore-forming mechanism. Venom-induced NaCl influx followed by water and consequent cell swelling most likely underlie the hemolytic and cytolytic activity of P. noctiluca venom. The present study underscores unique properties of P. noctiluca venom and provides essential information for a possible use of its active compounds and treatment of envenomation.

  4. Control of head morphogenesis in an invertebrate asexually produced larva-like bud ( Cassiopea andromeda; Cnidaria: Scyphozoa).

    PubMed

    Thieme, Claudia; Hofmann, Dietrich Kurt

    2003-04-01

    Scyphopolyps of Cassiopea andromeda propagate asexually by forming larva-like buds which separate from the parent in a developmentally quiescent state. These buds metamorphose into sessile polyps when exposed to specific biogenic, chemical inducers. Morphogenesis of transversely dissected buds indicates the presence of pattern-determining signals; whereas the basal bud fragments may still form a complete scyphistoma the apical bud fragments develop spontaneously in the absence of an inducer into a polyp head without stalk and foot. Based on these findings Neumann (dissertation, Cologne University, 1980) postulated a head-inhibiting signal which is released at the basal pole and inhibits head formation at the apical end. Contrary to this hypothesis dissection itself might induce the development of head structures. The present study deals with the control of polyp head formation in C. andromeda. It concentrates on two points, namely the postulated head inhibitor and the involvement of compounds known to act during metamorphosis (the enzyme protein kinase C and the specific metamorphosis inducer Z-GPGGPA). We found that compared to intact buds and apical bud fragments transversely incised buds reached an intermediate stage of head development. This confirms Neumann's hypothesis. Consequently we focused on the mode of action and the chemical nature of the head-inhibiting signal in C. andromeda. Our results indicate that the head inhibitor may be included in one of six pooled fractions isolated from bud homogenate via gel filtration on a Sephadex G-50 column. The inhibitor is supposed to be water-soluble and to have a molecular weight of 850-1,500 Da. Furthermore we prove that head formation is not promoted by the metamorphosis-inducer Z-GPGGPA but is prevented by the inhibitors psychosine, chelerythrine and RO-32-0432 showing the involvement of protein kinase C in this process.

  5. The unusual toxicity and stability properties of crude venom from isolated nematocysts of Pelagia noctiluca (Cnidaria, Scyphozoa).

    PubMed

    Marino, A; Crupi, R; Rizzo, G; Morabito, R; Musci, G; La Spada, G

    2007-09-17

    We have firstly investigated the toxicological activity by hemolytic assay of crude extract obtained by sonication of holotrichous isorhiza isolated nematocysts of the Scyphozoan Pelagia noctiluca, collected in the Strait of Messina. The hemolytic activity was both time- and dose-dependent on fish, rabbit, chicken and human red blood cells. At lowest doses rabbit and chicken erythrocytes were the most sensitive, whereas those of eel were the most resistant to the crude extract. Different storage conditions, such as -20 degrees C, -80 degrees C for up to 6 months and lyophilization, did not affect the stability of crude venom. Moreover, neither treatment at 4 degrees C, 20 degrees C and 37 degrees C for different time periods ranging between 30 min and 24 h, nor harsh thermal treatment at 80 degrees C and 100 degrees C affected the hemolytic power. The crude venom resulted even stable towards proteolysis and alkaline pH values.

  6. New family of allomorphic jellyfishes, Drymonematidae (Scyphozoa, Discomedusae), emphasizes evolution in the functional morphology and trophic ecology of gelatinous zooplankton.

    PubMed

    Bayha, Keith M; Dawson, Michael N

    2010-12-01

    Molecular analyses have revealed many cryptic species in the oceans, often permitting small morphological differences to be recognized as diagnosing species, but less commonly leading to consideration of cryptic ecology. Here, based on analyses of three nuclear DNA sequence markers (ribosomal 18S, 28S, and internal transcribed spacer 1 [ITS1]), two mitochondrial DNA markers (cytochrome c oxidase subunit I [COI] and ribosomal 16S), and 55 morphological features, we revise the classification of the enigmatic jellyfish genus Drymonema. We describe a new scyphozoan family, Drymonematidae, elevating the previous subfamily Drymonemidae to accommodate three species: the type species D. dalmatinum from the Mediterranean region, for which we identify a neotype; the western South Atlantic species D. gorgo; and a new species, D. larsoni from the western Atlantic and Caribbean, which also is described here. This revision emphasizes the remarkable morphological disparity of Drymonematidae from all other scyphomedusae, including allometric growth of the bell margin distal of the rhopalia, an annular zone of tentacles on the subumbrella, and ontogenetic loss of gastric filaments. Anatomical innovations are likely functionally related to predatory specialization on large gelatinous zooplankton, most notably the phylogenetically younger moon jellyfish Aurelia, indicating evolution of the feeding niche in Drymonematidae. This family-level revision contributes to the growing body of evidence that scyphomedusae are far more taxonomically rich, their biogeography is a more detailed mosaic, and their phenotypes are more nuanced than traditionally thought. Ecological and evolutionary responses to environmental change, past or future, are likely to be commensurately diverse.

  7. Induction of segmentation in polyps of Aurelia aurita (Scyphozoa, Cnidaria) into medusae and formation of mirror-image medusa anlagen.

    PubMed

    Kroiher, M; Siefker, B; Berking, S

    2000-08-01

    Polyps of Aurelia aurita can transform into several medusae (jellyfish) in a process of sequential subdivision. During this transformation, two processes take place which are well known to play a key role in the formation of various higher metazoa: segmentation and metamorphosis. In order to compare these processes in bilaterians and cnidarians we studied the control and the kinetics of these processes in Aurelia aurita. Segmentation and metamorphosis visibly start at the polyp's head and proceed down the body column but do not reach the basal disc. The small piece of polyp which remains will develop into a new polyp. The commitment to the medusa stage moves down the body column and precedes the visible onset of segmentation by about one day. Segmentation and metamorphosis can start at the cut surface of transversely cut body columns, leading to a mirror-image pattern of sequentially developing medusae.

  8. A novel proteinaceous cytotoxin from the northern Scyphozoa Cyanea capillata (L.) with structural homology to cubozoan haemolysins.

    PubMed

    Lassen, Stephan; Helmholz, Heike; Ruhnau, Christiane; Prange, Andreas

    2011-04-01

    It is well known that jellyfish are producers of complex mixtures of proteinaceous toxins for prey capture and defence. Nevertheless, studies on boreal scyphozoans concerning venom composition and toxic effects are rare. Here the isolation of a novel cytotoxic protein from the fishing tentacle venom of Cyanea capillata (L. 1758) using bioactivity-guided, multidimensional liquid chromatography is described. The crude venom was purified utilising preparative size-exclusion, ion-exchange, and reversed-phase chromatography. The cytotoxicity of resulting chromatographic fractions has been proven by a dye-uptake assay with the human hepatocyte cell line HepG2. The final purification step yielded, among other fractions, a fraction containing a single protein (named CcTX-1) with a molecular weight of its main isoform of 31.17 kDa The purification process leads to an increased cytotoxic activity per protein equivalents and the finally isolated CcTX-1 caused a nearly total loss of cell viability at a protein concentration of 1.3 μg mL⁻¹ corresponding to 0.4 μg/10⁵ cells. De novo sequencing of CcTX-1 was conducted after enzymatic digestion and subsequent matrix-assisted laser desorption ionisation time-of-flight/time-of-flight mass spectrometry (MALDI-ToF/ToF MS/MS). The obtained sequence data provide an approximate 85% description of the amino acid sequence. This sequence information partially matched that of two known haemolytic proteins of two cubozoan species: CaTX-1 from Carybdea alata Reynaud, 1830 and CrTX-1 from Carybdea rastonii Haacke, 1886. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Preliminary Study on Nematocyst Types and Venom Isolation of Cassiopea andromeda Forskål, 1775 (Scyphozoa, Cnidaria) from Turkey.

    PubMed

    Gülşahin, Nurçin

    2016-01-01

    Nematocyst types of Cassiopea andromeda were investigated. Medusae samples were taken from Güllük Bay, Muğla, Turkey. Nematocyst samples from oral arms of C. andromeda were observed on light microscope and photographed. Birhopaloid and a-isorhiza nematocyst types were found in C. andromeda. Moreover, it was seen that nematocyst sizes increased with increasing the bell diameters of the individuals. Also, the venom of the species was isolated and injected intramuscularly to Cyprinus carpio juveniles. Signs of partial paralysis, raking, and immobilized fins were observed in the juveniles consequently. Death was observed for the fishes which were 3-4 g in the range of weight. This study is a preliminary work on nematocysts and venom of C. andromeda. Further studies on neurotoxic effects of nematocyst venoms of this species should follow.

  10. Induction of stolon settlement in the scyphopolyps of Aurelia aurita (Cnidaria, Scyphozoa, Semaeostomeae) by glycolipids of marine bacteria

    NASA Astrophysics Data System (ADS)

    Schmahl, G.

    1985-06-01

    The settlement of pedal stolons of scyphopolyps of Aurelia aurita Lamarck could be induced by addition of a species of bacteria from the family Micrococcaceae. After treatment of the bacteria with several organic solvents a crude lipid extract free of bacteria could be obtained which was shown to be effective in inducing stolon settlement. Crude lipids extracted from the late logarithmic growth phase had an optimal effect on stolon attachment, in contrast to previously published experiments showing that all logarithmic phases of bacteria had the same level of effectiveness. After separation of the crude lipid extracts by thin layer chromatography and subsequent bioassay of the reeluated substances, acylgalactosidyldiglyceride and monogalactosidyldiglyceride were identified as the effective substances. Monogalactosidyldiglyceride was only found in bacteria from the medium logarithmic growth phase, whereas the former was found at all stages. The effectiveness of acylgalactosidyldiglyceride was independent of the growth phase of the extracted bacteria.

  11. Crude venom from nematocysts of Pelagia noctiluca (Cnidaria: Scyphozoa) elicits a sodium conductance in the plasma membrane of mammalian cells.

    PubMed

    Morabito, Rossana; Costa, Roberta; Rizzo, Valentina; Remigante, Alessia; Nofziger, Charity; La Spada, Giuseppa; Marino, Angela; Paulmichl, Markus; Dossena, Silvia

    2017-01-23

    Cnidarians may negatively impact human activities and public health but concomitantly their venom represents a rich source of bioactive substances. Pelagia noctiluca is the most venomous and abundant jellyfish of the Mediterranean Sea and possesses a venom with hemolytic and cytolytic activity for which the mechanism is largely unknown. Here we show that exposure of mammalian cells to crude venom from the nematocysts of P. noctiluca profoundly alters the ion conductance of the plasma membrane, therefore affecting homeostatic functions such as the regulation and maintenance of cellular volume. Venom-treated cells exhibited a large, inwardly rectifying current mainly due to permeation of Na(+) and Cl(-), sensitive to amiloride and completely abrogated following harsh thermal treatment of crude venom extract. Curiously, the plasma membrane conductance of Ca(2+) and K(+) was not affected. Current-inducing activity was also observed following delivery of venom to the cytosolic side of the plasma membrane, consistent with a pore-forming mechanism. Venom-induced NaCl influx followed by water and consequent cell swelling most likely underlie the hemolytic and cytolytic activity of P. noctiluca venom. The present study underscores unique properties of P. noctiluca venom and provides essential information for a possible use of its active compounds and treatment of envenomation.

  12. Monodisc strobilation in Japanese giant box jellyfish Morbakka virulenta (Kishinouye, 1910): a strong implication of phylogenetic similarity between Cubozoa and Scyphozoa.

    PubMed

    Toshino, Sho; Miyake, Hiroshi; Ohtsuka, Susumu; Adachi, Aya; Kondo, Yusuke; Okada, Shoma; Hirabayashi, Takeshi; Hiratsuka, Tatsuya

    2015-01-01

    Both sexes of the Japanese giant box jellyfish Morbakka virulenta were collected from the Seto Inland Sea, western Japan in December 2011, in order to observe the developmental processes from polyps to medusae. The medusa production in M. virulenta is up to now a unique process in cubozoans in that it exhibits a form of monodisc strobilation where the polyp is regenerated before the medusa detaches. This mode of medusa production was previously thought to be exclusive to scyphozoans. The general shape of young medusae resembles that of other cubozoans such as Alatina moseri and Copula sivickisi, but is differentiated from these by the short capitate tentacles and the lack of gastric filaments in the stomach. The unique medusa production of M. virulenta highly implies a phylogenetic similarity between cubozoans and scyphozoans.

  13. Jellyfish as prey: frequency of predation and selective foraging of Boops boops (Vertebrata, Actinopterygii) on the mauve stinger Pelagia noctiluca (Cnidaria, Scyphozoa).

    PubMed

    Milisenda, Giacomo; Rosa, Sara; Fuentes, Veronica L; Boero, Ferdinando; Guglielmo, Letterio; Purcell, Jennifer E; Piraino, Stefano

    2014-01-01

    In recent years, jellyfish blooms have attracted considerable scientific interest for their potential impacts on human activities and ecosystem functioning, with much attention paid to jellyfish as predators and to gelatinous biomass as a carbon sink. Other than qualitative data and observations, few studies have quantified direct predation of fish on jellyfish to clarify whether they may represent a seasonally abundant food source. Here we estimate predation frequency by the commercially valuable Mediterranean bogue, Boops boops on the mauve stinger jellyfish, Pelagia noctiluca, in the Strait of Messina (NE Sicily). A total of 1054 jellyfish were sampled throughout one year to quantify predation by B. boops from bite marks on partially eaten jellyfish and energy density of the jellyfish. Predation by B. boops in summer was almost twice that in winter, and they selectively fed according to medusa gender and body part. Calorimetric analysis and biochemical composition showed that female jellyfish gonads had significantly higher energy content than male gonads due to more lipids and that gonads had six-fold higher energy content than the somatic tissues due to higher lipid and protein concentrations. Energetically, jellyfish gonads represent a highly rewarding food source, largely available to B. boops throughout spring and summer. During the remainder of the year, when gonads were not very evident, fish predation switched towards less-selective foraging on the somatic gelatinous biomass. P. noctiluca, the most abundant jellyfish species in the Mediterranean Sea and a key planktonic predator, may represent not only a nuisance for human leisure activities and a source of mortality for fish eggs and larvae, but also an important resource for fish species of commercial value, such as B. boops.

  14. Comparative study of the toxic effects of Chrysaora quinquecirrha (Cnidaria: Scyphozoa) and Chironex fleckeri (Cnidaria: Cubozoa) venoms using cell-based assays.

    PubMed

    Ponce, Dalia; Brinkman, Diane L; Luna-Ramírez, Karen; Wright, Christine E; Dorantes-Aranda, Juan José

    2015-11-01

    The venoms of jellyfish cause toxic effects in diverse biological systems that can trigger local and systemic reactions. In this study, the cytotoxic and cytolytic effects of Chrysaora quinquecirrha and Chironex fleckeri venoms were assessed and compared using three in vitro assays. Venoms from both species were cytotoxic to fish gill cells and rat cardiomyocytes, and cytolytic in sheep erythrocytes. Both venoms decreased cell viability in a concentration-dependent manner; however, the greatest difference in venom potencies was observed in the fish gill cell line, wherein C. fleckeri was 12.2- (P = 0.0005) and 35.7-fold (P < 0.0001) more potently cytotoxic than C. quinquecirrha venom with 30 min and 120 min cell exposure periods, respectively. Gill cells and rat cardiomyocytes exposed to venoms showed morphological changes characterised by cell shrinkage, clumping and detachment. The cytotoxic effects of venoms may be caused by a group of toxic proteins that have been previously identified in C. fleckeri and other cubozoan jellyfish species. In this study, proteins homologous to CfTX-1 and CfTX-2 toxins from C. fleckeri and CqTX-A toxin from Chironex yamaguchii were identified in C. quinquecirrha venom using tandem mass spectrometry. The presence and relative abundance of these proteins may explain the differences in venom potency between cubozoan and scyphozoan jellyfish and may reflect their importance in the action of venoms.

  15. Interannual variability, growth, reproduction and feeding of Pelagia noctiluca (Cnidaria: Scyphozoa) in the Straits of Messina (Central Mediterranean Sea): Linkages with temperature and diet

    NASA Astrophysics Data System (ADS)

    Rosa, S.; Pansera, M.; Granata, A.; Guglielmo, L.

    2013-02-01

    To identify some of the possible environmental factors stimulating the increasingly frequent outbreaks of the scyphomedusa Pelagia noctiluca in the Straits of Messina, we investigated its abundance, growth, reproduction and feeding over a 4-year period, from 2007 to 2011, at two coastal sites. Using either field investigations and manipulative experiments we show that, among the various factors considered, shifts in water temperature (influencing medusae metabolism, growth and reproduction rates) and the size structure of the zooplankton community (their natural preys) can promote the proliferation of P. noctiluca. In particular, we show that increased temperature let jellyfishes to grow more rapidly and reach exceptional sizes. We also report a peculiar opportunistic behavior of P. noctiluca, which makes this species a potentially strong competitor in the pelagic trophic web of the Straits ecosystem. We therefore propose that more frequent P. noctiluca outbreaks stimulated by increasing sea surface temperature and shifts in their prey availability and composition would become, in the near future, a major cause of ecosystem shift.

  16. Offshore dispersion of ephyrae and medusae of Aurelia aurita s.l. (Cnidaria: Scyphozoa) from port enclosures: Physical and biological factors

    NASA Astrophysics Data System (ADS)

    Makabe, Ryosuke; Takeoka, Hidetaka; Uye, Shin-ichi

    2015-12-01

    Recurrent outbreaks of the common jellyfish Aurelia aurita s.l. have been increasingly significant, particularly in human perturbed coastal waters, where numerous artificial constructions increase suitable habitat for polyp populations. We examined the spatiotemporal dispersion process in 6 ports of ephyrae of A. aurita after release from strobilating polyps, to offshore waters of northern Harima Nada (eutrophic eastern Inland Sea of Japan) from January to May 2010. Almost exclusive occurrence of the ephyra stage in the ports demonstrated that their seeding polyps reside in the port enclosures, and liberated ephyrae are rapidly exported offshore by tidal water exchange. Post-ephyra stages occurred primarily outside the ports, and their age increased gradually offshore, ca. up to 9 km off the ports, and the pattern of age increase could be simulated by a simple diffusion model. However, there was an abrupt decline in A. aurita density beyond ca. 3 km off the shore, where jellyfish-eating Chrysaora pacifica medusae were prevalent. We conclude that physical forces are primarily responsible for offshore dispersion of A. aurita, and a biological factor, i.e. predation by C. pacifica, jointly affects the distribution pattern of A. aurita.

  17. A newly discovered oxidant defence system and its involvement in the development of Aurelia aurita (Scyphozoa, Cnidaria): reactive oxygen species and elemental iodine control medusa formation.

    PubMed

    Berking, Stefan; Czech, Nicole; Gerharz, Melanie; Herrmann, Klaus; Hoffmann, Uwe; Raifer, Hartmann; Sekul, Guy; Siefker, Barbara; Sommerei, Andrea; Vedder, Fritz

    2005-01-01

    In Aurelia aurita, applied iodine induces medusa formation (strobilation). This process also occurs when the temperature is lowered. This was found to increase oxidative stress resulting in an increased production of iodine from iodide. One polyp produces several medusae (initially termed ephyrae) starting at the polyp's oral end. The spreading of strobilation down the body column is controlled by a feedback loop: ephyra anlagen decrease the tyrosine content in adjacent polyp tissue by producing melanin from tyrosine. Endogenous tyrosine is able to remove iodine by forming iodiferous tyrosine compounds. The reduced level of tyrosine causes the ephyra-polyp-border to move towards the basal end of the former polyp. We argue that an oxidant defence system may exist which makes use of iodide and tyrosine. Like other marine invertebrates, polyps of Aurelia contain iodide ions. Inevitably produced peroxides oxidise iodide into iodine. The danger to be harmed by iodine is strongly decreased by endogenous tyrosine which reacts with iodine to form iodiferous tyrosine compounds including thyroxin. Both substances together, iodide and tyrosine, form an efficient oxidant defence system which shields the tissue against damage by reactive oxygen species. In the course of evolution (from a species at the basis of the animal kingdom like Aurelia to a highly evolved species like man) the waste product thyroxin (indicating a high metabolic rate) has developed into a hormone which controls the metabolic rate.

  18. Aurelia labiata (Scyphozoa) jellyfish in Roscoe Bay: Their spatial distribution varies with population size and their behaviour changes with water depth

    NASA Astrophysics Data System (ADS)

    Albert, David J.

    2009-02-01

    During 2003 and 2004, there were large numbers of Aurelia labiata medusae in Roscoe Bay and they distributed themselves across the entire bay. A smaller population present during 2006 and 2007 typically formed an aggregation in the west half of the bay. Since currents would have been the same during these two time periods, the behaviour of medusae must have influenced their distribution. The way medusae spaced themselves in aggregations appeared to interact with tidal currents to produce the difference in medusae distribution during the two time periods. In a second series of observations, I found that medusae were not stranded on a Roscoe Bay beach by ebb tides. When the depth of the water column declined to about 1 m or less, medusae in an intertidal zone dove down and bumped into the bottom or swam into rocks or oysters. Their response to these collisions was to swim to the surface or within a few centimetres of the surface. Since the ebb stream was at the surface, being at the surface increased the probability that medusae drifted out of the intertidal zone. The influence of medusae behaviour on their distribution and on their avoidance of stranding is a further indication of the importance of adaptive behaviour in the ecology of Aurelia labiata medusae.

  19. Jellyfish as Prey: Frequency of Predation and Selective Foraging of Boops boops (Vertebrata, Actinopterygii) on the Mauve Stinger Pelagia noctiluca (Cnidaria, Scyphozoa)

    PubMed Central

    Fuentes, Veronica L.; Boero, Ferdinando; Guglielmo, Letterio; Purcell, Jennifer E.; Piraino, Stefano

    2014-01-01

    In recent years, jellyfish blooms have attracted considerable scientific interest for their potential impacts on human activities and ecosystem functioning, with much attention paid to jellyfish as predators and to gelatinous biomass as a carbon sink. Other than qualitative data and observations, few studies have quantified direct predation of fish on jellyfish to clarify whether they may represent a seasonally abundant food source. Here we estimate predation frequency by the commercially valuable Mediterranean bogue, Boops boops on the mauve stinger jellyfish, Pelagia noctiluca, in the Strait of Messina (NE Sicily). A total of 1054 jellyfish were sampled throughout one year to quantify predation by B. boops from bite marks on partially eaten jellyfish and energy density of the jellyfish. Predation by B. boops in summer was almost twice that in winter, and they selectively fed according to medusa gender and body part. Calorimetric analysis and biochemical composition showed that female jellyfish gonads had significantly higher energy content than male gonads due to more lipids and that gonads had six-fold higher energy content than the somatic tissues due to higher lipid and protein concentrations. Energetically, jellyfish gonads represent a highly rewarding food source, largely available to B. boops throughout spring and summer. During the remainder of the year, when gonads were not very evident, fish predation switched towards less-selective foraging on the somatic gelatinous biomass. P. noctiluca, the most abundant jellyfish species in the Mediterranean Sea and a key planktonic predator, may represent not only a nuisance for human leisure activities and a source of mortality for fish eggs and larvae, but also an important resource for fish species of commercial value, such as B. boops. PMID:24727977

  20. Commencement Bay Study. Volume IV. Invertebrates.

    DTIC Science & Technology

    1981-12-31

    BAY Taxa Epibenthic Pump Infaunal Core Hydrozoa Hydroida (polyp) + Scyphozoa Scyphozoan medusae + Nemertea + Nematoda + + Turbellaria Polycladida...several species included Cumacea (7 species), ysidacea (4 species), and Tanaidacea (4 species) (Table 4). The Nematoda and Oligochaeta were often very...harpacticoid copepods, Corophium, Cumella vulgaris, and Pancolus californiensis. Nematoda , Oligochaeta, and Harpacticoida are distributed over all the

  1. Mitochondrial genome of the freshwater jellyfish Craspedacusta sowerbyi and phylogenetics of Medusozoa.

    PubMed

    Zou, Hong; Zhang, Jin; Li, Wenxiang; Wu, Shangong; Wang, Guitang

    2012-01-01

    The 17,922 base pairs (bp) nucleotide sequence of the linear mitochondrial DNA (mtDNA) molecule of the freshwater jellyfish Craspedacusta sowerbyi (Hydrozoa, Trachylina, Limnomedusae) has been determined. This sequence exhibits surprisingly low A+T content (57.1%), containing genes for 13 energy pathway proteins, a small and a large subunit rRNAs, and methionine and tryptophan tRNAs. Mitochondrial ancestral medusozoan gene order (AMGO) was found in the C. sowerbyi, as those found in Cubaia aphrodite (Hydrozoa, Trachylina, Limnomedusae), discomedusan Scyphozoa and Staurozoa. The genes of C. sowerbyi mtDNA are arranged in two clusters with opposite transcriptional polarities, whereby transcription proceeds toward the ends of the DNA molecule. Identical inverted terminal repeats (ITRs) flank the ends of the mitochondrial DNA molecule, a characteristic typical of medusozoans. In addition, two open reading frames (ORFs) of 354 and 1611 bp in length were found downstream of the large subunit rRNA gene, similar to the two ORFs of ORF314 and polB discovered in the linear mtDNA of C. aphrodite, discomedusan Scyphozoa and Staurozoa. Phylogenetic analyses of C. sowerbyi and other cnidarians were carried out based on both nucleotide and inferred amino acid sequences of the 13 mitochondrial energy pathway genes. Our working hypothesis supports the monophyletic Medusozoa being a sister group to Octocorallia (Cnidaria, Anthozoa). Within Medusozoa, the phylogenetic analysis suggests that Staurozoa may be the earliest diverging class and the sister group of all other medusozoans. Cubozoa and coronate Scyphozoa form a clade that is the sister group of Hydrozoa plus discomedusan Scyphozoa. Hydrozoa is the sister group of discomedusan Scyphozoa. Semaeostomeae is a paraphyletic clade with Rhizostomeae, while Limnomedusae (Trachylina) is the sister group of hydroidolinans and may be the earliest diverging lineage among Hydrozoa.

  2. Mitochondrial Genome of the Freshwater Jellyfish Craspedacusta sowerbyi and Phylogenetics of Medusozoa

    PubMed Central

    Zou, Hong; Zhang, Jin; Li, Wenxiang; Wu, Shangong; Wang, Guitang

    2012-01-01

    The 17,922 base pairs (bp) nucleotide sequence of the linear mitochondrial DNA (mtDNA) molecule of the freshwater jellyfish Craspedacusta sowerbyi (Hydrozoa,Trachylina, Limnomedusae) has been determined. This sequence exhibits surprisingly low A+T content (57.1%), containing genes for 13 energy pathway proteins, a small and a large subunit rRNAs, and methionine and tryptophan tRNAs. Mitochondrial ancestral medusozoan gene order (AMGO) was found in the C. sowerbyi, as those found in Cubaia aphrodite (Hydrozoa, Trachylina, Limnomedusae), discomedusan Scyphozoa and Staurozoa. The genes of C. sowerbyi mtDNA are arranged in two clusters with opposite transcriptional polarities, whereby transcription proceeds toward the ends of the DNA molecule. Identical inverted terminal repeats (ITRs) flank the ends of the mitochondrial DNA molecule, a characteristic typical of medusozoans. In addition, two open reading frames (ORFs) of 354 and 1611 bp in length were found downstream of the large subunit rRNA gene, similar to the two ORFs of ORF314 and polB discovered in the linear mtDNA of C. aphrodite, discomedusan Scyphozoa and Staurozoa. Phylogenetic analyses of C. sowerbyi and other cnidarians were carried out based on both nucleotide and inferred amino acid sequences of the 13 mitochondrial energy pathway genes. Our working hypothesis supports the monophyletic Medusozoa being a sister group to Octocorallia (Cnidaria, Anthozoa). Within Medusozoa, the phylogenetic analysis suggests that Staurozoa may be the earliest diverging class and the sister group of all other medusozoans. Cubozoa and coronate Scyphozoa form a clade that is the sister group of Hydrozoa plus discomedusan Scyphozoa. Hydrozoa is the sister group of discomedusan Scyphozoa. Semaeostomeae is a paraphyletic clade with Rhizostomeae, while Limnomedusae (Trachylina) is the sister group of hydroidolinans and may be the earliest diverging lineage among Hydrozoa. PMID:23240028

  3. Cnidarian phylogenetic relationships as revealed by mitogenomics

    PubMed Central

    2013-01-01

    Background Cnidaria (corals, sea anemones, hydroids, jellyfish) is a phylum of relatively simple aquatic animals characterized by the presence of the cnidocyst: a cell containing a giant capsular organelle with an eversible tubule (cnida). Species within Cnidaria have life cycles that involve one or both of the two distinct body forms, a typically benthic polyp, which may or may not be colonial, and a typically pelagic mostly solitary medusa. The currently accepted taxonomic scheme subdivides Cnidaria into two main assemblages: Anthozoa (Hexacorallia + Octocorallia) – cnidarians with a reproductive polyp and the absence of a medusa stage – and Medusozoa (Cubozoa, Hydrozoa, Scyphozoa, Staurozoa) – cnidarians that usually possess a reproductive medusa stage. Hypothesized relationships among these taxa greatly impact interpretations of cnidarian character evolution. Results We expanded the sampling of cnidarian mitochondrial genomes, particularly from Medusozoa, to reevaluate phylogenetic relationships within Cnidaria. Our phylogenetic analyses based on a mitochogenomic dataset support many prior hypotheses, including monophyly of Hexacorallia, Octocorallia, Medusozoa, Cubozoa, Staurozoa, Hydrozoa, Carybdeida, Chirodropida, and Hydroidolina, but reject the monophyly of Anthozoa, indicating that the Octocorallia + Medusozoa relationship is not the result of sampling bias, as proposed earlier. Further, our analyses contradict Scyphozoa [Discomedusae + Coronatae], Acraspeda [Cubozoa + Scyphozoa], as well as the hypothesis that Staurozoa is the sister group to all the other medusozoans. Conclusions Cnidarian mitochondrial genomic data contain phylogenetic signal informative for understanding the evolutionary history of this phylum. Mitogenome-based phylogenies, which reject the monophyly of Anthozoa, provide further evidence for the polyp-first hypothesis. By rejecting the traditional Acraspeda and Scyphozoa hypotheses, these analyses suggest that

  4. Cnidarian phylogenetic relationships as revealed by mitogenomics.

    PubMed

    Kayal, Ehsan; Roure, Béatrice; Philippe, Hervé; Collins, Allen G; Lavrov, Dennis V

    2013-01-09

    Cnidaria (corals, sea anemones, hydroids, jellyfish) is a phylum of relatively simple aquatic animals characterized by the presence of the cnidocyst: a cell containing a giant capsular organelle with an eversible tubule (cnida). Species within Cnidaria have life cycles that involve one or both of the two distinct body forms, a typically benthic polyp, which may or may not be colonial, and a typically pelagic mostly solitary medusa. The currently accepted taxonomic scheme subdivides Cnidaria into two main assemblages: Anthozoa (Hexacorallia + Octocorallia) - cnidarians with a reproductive polyp and the absence of a medusa stage - and Medusozoa (Cubozoa, Hydrozoa, Scyphozoa, Staurozoa) - cnidarians that usually possess a reproductive medusa stage. Hypothesized relationships among these taxa greatly impact interpretations of cnidarian character evolution. We expanded the sampling of cnidarian mitochondrial genomes, particularly from Medusozoa, to reevaluate phylogenetic relationships within Cnidaria. Our phylogenetic analyses based on a mitochogenomic dataset support many prior hypotheses, including monophyly of Hexacorallia, Octocorallia, Medusozoa, Cubozoa, Staurozoa, Hydrozoa, Carybdeida, Chirodropida, and Hydroidolina, but reject the monophyly of Anthozoa, indicating that the Octocorallia + Medusozoa relationship is not the result of sampling bias, as proposed earlier. Further, our analyses contradict Scyphozoa [Discomedusae + Coronatae], Acraspeda [Cubozoa + Scyphozoa], as well as the hypothesis that Staurozoa is the sister group to all the other medusozoans. Cnidarian mitochondrial genomic data contain phylogenetic signal informative for understanding the evolutionary history of this phylum. Mitogenome-based phylogenies, which reject the monophyly of Anthozoa, provide further evidence for the polyp-first hypothesis. By rejecting the traditional Acraspeda and Scyphozoa hypotheses, these analyses suggest that the shared morphological characters in

  5. The importance of cnidarian synapses for neurobiology.

    PubMed

    Anderson, P A; Spencer, A N

    1989-07-01

    Despite being the most primitive organisms to possess a nervous system, cnidarians afford rare opportunities for studying various, general aspects of chemical synaptic transmission. This is made possible by the unique organization of their nervous systems and by the fact that in certain species the neurons and synapses are readily accessible for intracellular recordings and voltage clamp. The results obtained from such studies are summarized here, with particular emphasis on work with two species, Cyanea capillata (Scyphozoa) and Polyorchis pennicilatus (Hydrozoa). The potential of these preparations for providing additional data is also discussed.

  6. Direct Gene Transfer into Plant Mature Seeds via Electroporation After Vacuum Treatment

    NASA Astrophysics Data System (ADS)

    Hagio, Takashi

    A number of direct gene transfer methods have been used successfully in plant genetic engineering, providing powerful tools to investigate fundamental and applied problems in plant biology (Chowrira et al., 1996; D'halluin et al., 1992; Morandini and Salamini, 2003; Rakoczy-Trojanowska, 2002; Songstad et al., 1995). In cereals, several methods have been found to be suitable for obtaining transgenic plant; these include bombardment of scutellum (Hagio et al., 1995) and inflorescence cultures (He et al., 2001), and silicon carbide fiber-mediated DNA delivery (Asano et al., 1991) and Agrobacterium tumefaciens transformation (Potrykus, 1990). Electroporation of cereal protoplasts also has proved successful but it involves prolonged cell treatments and generally is limited by the difficulties of regeneration from cereal protoplast cultures (Fromm et al., 1987). Many laboratories worldwide are now using Agrobacterium as a vehicle for routine production of transgenic crop plants. The primary application of the particle system (Klein et al., 1987) has been for transformation of species recalcitrant to conventional Agrobacterium (Binns, 1990) or protoplast methods. But these conventional methods can be applied to the species and varieties that are amenable to tissue culture (Machii et al., 1998). Mature seeds are readily available and free from the seasonal limits that immature embryo, inflorescence, and anther have. This method enables us to produce transgenic plants without time-consuming tissue culture process.

  7. Adoption of conserved developmental genes in development and origin of the medusa body plan.

    PubMed

    Kraus, Johanna E M; Fredman, David; Wang, Wei; Khalturin, Konstantin; Technau, Ulrich

    2015-01-01

    The metagenesis of sessile polyps into pelagic medusae in cnidarians represents one of the most ancient complex life cycles in animals. Interestingly, scyphozoans and hydrozoans generate medusae by apparently fundamentally different processes. It is therefore unclear whether medusa formation has evolved independently in different medusozoans. To this end, a thorough understanding of the correspondence of polyp and medusa is required. We monitored the expression patterns of conserved developmental genes in developing medusae of Clytia hemisphaerica (Hydrozoa) and Aurelia aurita (Scyphozoa) and found that developing medusae and polyps share similarities in their morphology and developmental gene expression. Unexpectedly, however, polyp tentacle marker genes were consistently expressed in the developing medusa bell, suggesting that the bell of medusae corresponds to modified and fused polyp tentacle anlagen. Our data represent the first comparative gene expression analysis of developing medusae in two representatives of Scyphozoa and Hydrozoa. The results challenge prevailing views about polyp medusa body plan homology. We propose that the evolution of a new life stage may be facilitated by the adoption of existing developmental genes.

  8. Evidence for a common pattern of peptidergic innervation of cnidocytes.

    PubMed

    Anderson, Peter A V; Thompson, Louise F; Moneypenny, Craig G

    2004-10-01

    Tentacles from representatives of all four classes of the phylum Cnidaria were examined using antibodies against the neuropeptides FMRFamide and RFamide to reveal the organization of neurons and nerve nets associated with cnidocytes. The tentacles of all species examined contained FMRFamide- or RFamide-immunoreactive neurons, in varying densities. In representatives from the Scyphozoa, Hydrozoa, and Cubozoa, the FMRFamide-immunoreactive neurons formed plexuses at the base of the cnidocyte assemblages; in anthozoans, the absence of discrete assemblies of cnidocytes precluded visual co-localization of cnidocytes and immunoreactive neurons. In all four classes, immunoreactive sensory cells connected these peptidergic nerve nets to the surface of the tentacle. These findings suggest that members of all four cnidarian classes share a common organizational pattern, and it is proposed that this peptidergic innervation may be involved in the chemosensory regulation of cnidocyte discharge.

  9. Phylogenomic Analyses Support Traditional Relationships within Cnidaria.

    PubMed

    Zapata, Felipe; Goetz, Freya E; Smith, Stephen A; Howison, Mark; Siebert, Stefan; Church, Samuel H; Sanders, Steven M; Ames, Cheryl Lewis; McFadden, Catherine S; France, Scott C; Daly, Marymegan; Collins, Allen G; Haddock, Steven H D; Dunn, Casey W; Cartwright, Paulyn

    2015-01-01

    Cnidaria, the sister group to Bilateria, is a highly diverse group of animals in terms of morphology, lifecycles, ecology, and development. How this diversity originated and evolved is not well understood because phylogenetic relationships among major cnidarian lineages are unclear, and recent studies present contrasting phylogenetic hypotheses. Here, we use transcriptome data from 15 newly-sequenced species in combination with 26 publicly available genomes and transcriptomes to assess phylogenetic relationships among major cnidarian lineages. Phylogenetic analyses using different partition schemes and models of molecular evolution, as well as topology tests for alternative phylogenetic relationships, support the monophyly of Medusozoa, Anthozoa, Octocorallia, Hydrozoa, and a clade consisting of Staurozoa, Cubozoa, and Scyphozoa. Support for the monophyly of Hexacorallia is weak due to the equivocal position of Ceriantharia. Taken together, these results further resolve deep cnidarian relationships, largely support traditional phylogenetic views on relationships, and provide a historical framework for studying the evolutionary processes involved in one of the most ancient animal radiations.

  10. Die Metamorphose des Polypen von Tripedalia cystophora (Cubozoa, Carybdeidae) in die Meduse

    NASA Astrophysics Data System (ADS)

    Werner, B.

    1983-09-01

    The life cycle of the Cubozoa is unique due to the complete metamorphosis of the sessible solitary polyp into one single medusa which starts a pelagic way of life. Contrary to the other metagenetic classes of Scyphozoa and Hydrozoa, the cubozoan polyp terminates its polypoid existence definitely when it metamorphosizes. Generally, the metamorphosis of the cubopolyp is characterized by the transformation of its simple, sac-like multiradial body into the tetraradial structures of the much more complicated medusa. The macroscopic phases of the metamorphosis of Tripedalia cystophora Conant are reviewed, and the internal developmental processes which effect and underlie the transformation are described in detail from new histological investigations. Only the oral pole of the polyp is involved in the active processes of transformation whereas the basal pole follows in a more passive way. The most important process is the invagination of a quadrangular furrow around the hypostome of the polyp by which (a) the subumbrellar room (bell cavity) of the developing medusa is formed, and (b) the four gastric pockets within the wall of the bell are folded off from the polyp's simple stomach. The description of the metamorphosis on the whole and the detailed comparison of the principal developmental processes provide evidence that medusa formation of Cubozoa is different from that of the other metagenetic classes of Scyphozoa and Hydrozoa. The systematic and evolutionary consequences as well as general aspects of medusa formation in the phylum Cnidaria are discussed in detail. In conclusion, the pelagic medusa generation has been “invented” by the ancestors of the recent metagenetic cnidarian classes three times independently.

  11. Catostylus tagi: partial rDNA sequencing and characterisation of nematocyte structures using two improvements in jellyfish sample preparation.

    PubMed

    Parracho, Tiago; Morais, Zilda

    2015-01-01

    More than 200 Scyphozoa species have been described, but few have been properly studied regarding their chemical and genetic characteristics. Catostylus tagi, an edible Scyphozoa and the sole European Catostylidae, occurs in summer at Tagus and Sado estuaries. Neither a systematic comparison between the two Catostylus communities nor a chemical approach on their nematocytes had been carried out yet. In order to achieve these purposes, optimisation of DNA extraction and of histochemical staining procedures were developed. Catostylus specimens from Tagus and Sado estuaries were compared by ribosomal 18S, 28S, and ITS1 partial sequencing. The morphochemistry of nematocytes was studied by optical and electronic microscopy. Macroscopic and molecular results indicated that both communities belong to the same species, C. tagi. The hematoxylin and eosin staining allowed the visualisation of nematocyst genesis and indicated a basic character for the macromolecules on the shaft of euryteles and on the tubule of isorhizae and birhopaloids. By Masson's trichrome procedure, the basic properties of the tubules were confirmed and a collagenous profile for the toxins was suggested. Results of the alcian blue staining showed that the outer membrane of nematocyte may consist of macromolecules with acidic polysaccharides, consistent with NOWA and nematogalectin glycoproteins detected in Hydra, but also with poly-gamma-glutamate complex, chitin-like polysaccharides and hyaluronic acids. Through the von Kossa assays, calcium was detected; its position suggested interactions with polysaccharides of the membrane, with proteins of the contractile system or with both. The optimisation of sample preparation for DNA extraction may facilitate further studies on little known jellyfish species. The improvement of the smear procedure simplified the use of stained reactions in zooplankton. Moreover, it was shown that good slide images might be acquired manually. The development of specific

  12. Phylogenomic Analyses Support Traditional Relationships within Cnidaria

    PubMed Central

    Zapata, Felipe; Goetz, Freya E.; Smith, Stephen A.; Howison, Mark; Siebert, Stefan; Church, Samuel H.; Sanders, Steven M.; Ames, Cheryl Lewis; McFadden, Catherine S.; France, Scott C.; Daly, Marymegan; Collins, Allen G.; Haddock, Steven H. D.; Dunn, Casey W.; Cartwright, Paulyn

    2015-01-01

    Cnidaria, the sister group to Bilateria, is a highly diverse group of animals in terms of morphology, lifecycles, ecology, and development. How this diversity originated and evolved is not well understood because phylogenetic relationships among major cnidarian lineages are unclear, and recent studies present contrasting phylogenetic hypotheses. Here, we use transcriptome data from 15 newly-sequenced species in combination with 26 publicly available genomes and transcriptomes to assess phylogenetic relationships among major cnidarian lineages. Phylogenetic analyses using different partition schemes and models of molecular evolution, as well as topology tests for alternative phylogenetic relationships, support the monophyly of Medusozoa, Anthozoa, Octocorallia, Hydrozoa, and a clade consisting of Staurozoa, Cubozoa, and Scyphozoa. Support for the monophyly of Hexacorallia is weak due to the equivocal position of Ceriantharia. Taken together, these results further resolve deep cnidarian relationships, largely support traditional phylogenetic views on relationships, and provide a historical framework for studying the evolutionary processes involved in one of the most ancient animal radiations. PMID:26465609

  13. Quantification of bioluminescence from the surface to the deep sea demonstrates its predominance as an ecological trait.

    PubMed

    Martini, Séverine; Haddock, Steven H D

    2017-04-04

    The capability of animals to emit light, called bioluminescence, is considered to be a major factor in ecological interactions. Because it occurs across diverse taxa, measurements of bioluminescence can be powerful to detect and quantify organisms in the ocean. In this study, 17 years of video observations were recorded by remotely operated vehicles during surveys off the California Coast, from the surface down to 3,900 m depth. More than 350,000 observations are classified for their bioluminescence capability based on literature descriptions. The organisms represented 553 phylogenetic concepts (species, genera or families, at the most precise taxonomic level defined from the images), distributed within 13 broader taxonomic categories. The importance of bioluminescent marine taxa is highlighted in the water column, as we showed that 76% of the observed individuals have bioluminescence capability. More than 97% of Cnidarians were bioluminescent, and 9 of the 13 taxonomic categories were found to be bioluminescent dominant. The percentage of bioluminescent animals is remarkably uniform over depth. Moreover, the proportion of bioluminescent and non-bioluminescent animals within taxonomic groups changes with depth for Ctenophora, Scyphozoa, Chaetognatha, and Crustacea. Given these results, bioluminescence has to be considered an important ecological trait from the surface to the deep-sea.

  14. Scyphomedusae of the Mediterranean: state of the art and future perspectives.

    PubMed

    D'Ambra, Isabella; Malej, Alenka

    2015-01-01

    Scyphomedusae (Phylum Cnidaria, Class Scyphozoa) are perceived as a nuisance due to their sudden outbreaks that negatively affect human activities (particularly tourism and fisheries) mainly because of their stings. A brief review of the history of scyphozoan blooms in the Mediterranean and updated information available after 2010 point to an increase in scyphozoan outbreaks. Whilst the negative effects on public health, aquaculture, coastal industrial activities and fisheries operations are undeniable, the effects on the ecosystem are not well defined. We focus on the trophic interactions between scyphomedusae and fish, highlighting that the negative effects of scyphomedusae on fish stocks exerted through direct predation on early life stages of fish and competition for plankton are at present speculative. In favor of a positive effect of scyphomedusae on fish populations, the reports of predation upon scyphozoans are increasing, which suggests that predators may benefit from the availability of scyphozoans by shifting their diet toward jelly prey. Additionally, scyphomedusae may provide nursery habitats to early life stages of ecologically and economically important forage fishes and other organisms which shelter underneath their bells. Together with these ecosystem services, compounds extracted from scyphozoan tissues and venoms are having a variety of biomedical applications and are likely to contribute to treat a growing number of diseases, including cancer. Our analysis highlights that a re-evaluation of the balance between "positive" and "negative" effects of scyphomedusae on the ecosystem and human activities is needed and provides indications on potential directions for future studies.

  15. Interactions of cnidarian toxins with the immune system.

    PubMed

    Suput, Dusan

    2011-10-01

    Cnidarians comprise four classes of toxic marine animals: Anthozoa, Cubozoa, Scyphozoa and Hydrozoa. They are the largest and probably the oldest phylum of toxic marine animals. Any contact with a cnidarian, especially the box jellyfish (Chironex fleckeri), can be fatal, but most cnidarians do not possess sufficiently strong venomous apparatus to penetrate the human skin, whereas others rarely come into contact with human beings. Only a small, almost negligible percentage of the vast wealth of cnidarian toxins has been studied in detail. Many polypeptide cnidarian toxins are immunogenic, and cross-reactivity between several jellyfish venoms has been reported. Cnidarians also possess components of innate immunity, and some of those components have been preserved in evolution. On the other hand, cnidarian toxins have already been used for the design of immunotoxins to treat cancer, whereas other cnidarian toxins can modulate the immune system in mammals, including man. This review will focus on a short overview of cnidarian toxins, on the innate immunity of cnidarians, and on the mode of action of cnidarian toxins which can modulate the immune system in mammals. Emphasis is palced on those toxins which block voltage activated potassium channels in the cells of the immune system.

  16. [The plate in the zone of oocyte and germinal epithelium contact in scyphomedusa Aurelia aurita binds antibodies to ZP-domain-containing protein mesoglein].

    PubMed

    Adonin, L S; Podgornaia, O I; Matveev, I V; Shaposhnikova, T G

    2009-01-01

    Cnidaria are lower multicellular animals with the body consisting of two epithelial layers. An extracellular substance--mesoglea--is situated between epidermal and gastrodermal layers of these animals. Mesoglein is one of the major mesogleal proteins of adult medusa of Scyphozoan jellyfish Aurelia aurita. Search for the known domains in mesoglein amino acid sequence reveals prominent zona pellucida (ZP) domain (which was found at first in the mammal oocyte zona pellucida proteins), so the protein belongs to ZP family of extracellular matrix proteins and it is an early metazoan member of ZP-domain-containing protein family. However, nothing is known about oogenesis related ZP-domain proteins in the lower multicellular animals. Oogenesis in Scyphozoa is described poorly. In this work morphological features of the zone in contact area between the oocyte and the germinal epithelium were investigated in semi-fine sections: To make it more convenient we identified seven stages according to the oocyte size and the structure found in this area was named the plate. It was shown that the components of the plate bound specifically the antibodies against mesoglein. So it seems the plate material contains ZP-domain proteins. Electrophoresis and immunoblot results give evidence that the proteins immunologically related to mesoglein have a higher molecular mass. It might be due to either the posttranslational modifications of the precursors or that they represent other proteins of ZP-domain family in Cnidaria.

  17. Modulation of jellyfish nematocyst discharges and management of human skin stings in Nemopilema nomurai and Carybdea mora.

    PubMed

    Pyo, Min-Jung; Lee, Hyunkyoung; Bae, Seong Kyong; Heo, Yunwi; Choudhary, Indu; Yoon, Won Duk; Kang, Changkeun; Kim, Euikyung

    2016-01-01

    Even though jellyfish sting is common today, its first aid guideline has never been clear enough in a scientific point of view and the use of vinegar appears to be not accepted in common throughout the world. In the present study, to develop rational first aid guidelines for the stings of Nemopilema nomurai (scyphozoa) and Carybdea mora (cubozoa), the modulatory effects of various kinds of rinsing solutions have been assessed on nematocyst discharge and human skin tests. Among the solutions tested, vinegar (4% acetic acid) immediately caused significant nematocyst discharge in N. nomurai but not in C. mora. On the other hand, ethanol (70%) notably stimulated nematocyst discharge in C. mora and relatively less in N. nomurai. Moreover, isopropanol, a widely used solvent in pharmaceutical products, caused extensive nematocyst discharges in both N. nomurai and C. mora. Whereas, seawater did not elicit any nematocyst discharge in both jellyfish species. In human skin test, the rinsing with seawater also ameliorated the stinging-associated symptoms (pain and redness) in C. mora as well as N. nomurai. From this study, seawater appears not to induce any nematocyst discharge and can be safely used as a first aid rinsing solution for the jellyfish stings.

  18. Isolation of a Nav channel blocking polypeptide from Cyanea capillata medusae - a neurotoxin contained in fishing tentacle isorhizas.

    PubMed

    Lassen, Stephan; Wiebring, Annika; Helmholz, Heike; Ruhnau, Christiane; Prange, Andreas

    2012-05-01

    Jellyfish are efficient predators which prey on crabs, fish larvae, and small fish. Their venoms consist of various toxins including neurotoxins that paralyse prey organisms immediately. One possible mode of action of neurotoxins is the blockage of voltage-gated sodium (Na(v)) channels. A novel polypeptide with Na(v) channel blocking activity was isolated from the northern Scyphozoa Cyanea capillata (L., 1758). For that purpose, a bioactivity-guided multidimensional liquid chromatographic purification method has been developed. A neurotoxic activity of resulting chromatographic fractions was demonstrated by a bioassay, which based on the mouse neuroblastoma cell line Neuro2A. The purification process yielded one fraction containing a single polypeptide with proven activity. The molecular weight of 8.22 kDa was determined by matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-ToF MS). Utilising Laser Microdissection and Pressure Catapulting (LMPC) for the separation of different nematocyst types in combination with direct MALDI-ToF MS analysis of the intact capsules, the neurotoxin was found to be present in all types of fishing tentacle isorhizas (A-isorhizas, a-isorhizas, O-isorhizas) of C. capillata medusae. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Quantification of bioluminescence from the surface to the deep sea demonstrates its predominance as an ecological trait

    PubMed Central

    Martini, Séverine; Haddock, Steven H. D.

    2017-01-01

    The capability of animals to emit light, called bioluminescence, is considered to be a major factor in ecological interactions. Because it occurs across diverse taxa, measurements of bioluminescence can be powerful to detect and quantify organisms in the ocean. In this study, 17 years of video observations were recorded by remotely operated vehicles during surveys off the California Coast, from the surface down to 3,900 m depth. More than 350,000 observations are classified for their bioluminescence capability based on literature descriptions. The organisms represented 553 phylogenetic concepts (species, genera or families, at the most precise taxonomic level defined from the images), distributed within 13 broader taxonomic categories. The importance of bioluminescent marine taxa is highlighted in the water column, as we showed that 76% of the observed individuals have bioluminescence capability. More than 97% of Cnidarians were bioluminescent, and 9 of the 13 taxonomic categories were found to be bioluminescent dominant. The percentage of bioluminescent animals is remarkably uniform over depth. Moreover, the proportion of bioluminescent and non-bioluminescent animals within taxonomic groups changes with depth for Ctenophora, Scyphozoa, Chaetognatha, and Crustacea. Given these results, bioluminescence has to be considered an important ecological trait from the surface to the deep-sea. PMID:28374789

  20. Insight into the Molecular and Functional Diversity of Cnidarian Neuropeptides

    PubMed Central

    Takahashi, Toshio; Takeda, Noriyo

    2015-01-01

    Cnidarians are the most primitive animals to possess a nervous system. This phylum is composed of the classes Scyphozoa (jellyfish), Cubozoa (box jellyfish), and Hydrozoa (e.g., Hydra, Hydractinia), which make up the subphylum Medusozoa, as well as the class Anthozoa (sea anemones and corals). Neuropeptides have an early evolutionary origin and are already abundant in cnidarians. For example, from the cnidarian Hydra, a key model system for studying the peptides involved in developmental and physiological processes, we identified a wide variety of novel neuropeptides from Hydra magnipapillata (the Hydra Peptide Project). Most of these peptides act directly on muscle cells and induce contraction and relaxation. Some peptides are involved in cell differentiation and morphogenesis. In this review, we describe FMRFamide-like peptides (FLPs), GLWamide-family peptides, and the neuropeptide Hym-355; FPQSFLPRGamide. Several hundred FLPs have been isolated from invertebrate animals such as cnidarians. GLWamide-family peptides function as signaling molecules in muscle contraction, metamorphosis, and settlement in cnidarians. Hym-355; FPQSFLPRGamide enhances neuronal differentiation in Hydra. Recently, GLWamide-family peptides and Hym-355; FPQSFLPRGamide were shown to trigger oocyte maturation and subsequent spawning in the hydrozoan jellyfish Cytaeis uchidae. These findings suggest the importance of these neuropeptides in both developmental and physiological processes. PMID:25625515

  1. Internal and external relationships of the Cnidaria: implications of primary and predicted secondary structure of the 5'-end of the 23S-like rDNA.

    PubMed

    Odorico, D M; Miller, D J

    1997-01-22

    Since both internal (class-level) and external relationships of the Cnidaria remain unclear on the basis of analyses of 18S and (partial) 16S rDNA sequence data, we examined the informativeness of the 5'-end of the 23S-like rDNA. Here we describe analyses of both primary and predicted secondary structure data for this region from the ctenophore Bolinopsis sp., the placozoan Trichoplax adhaerens, the sponge Hymeniacidon heliophila, and representatives of all four cnidarian classes. Primary sequence analyses clearly resolved the Cnidaria from other lower Metazoa, supported sister group relationships between the Scyphozoa and Cubozoa and between the Ctenophora and the Placozoa, and confirmed the basal status of the Anthozoa within the Cnidaria. Additionally, in the ctenophore, placozoan and sponge, non-canonical base pairing is required to maintain the secondary structure of the B12 region, whereas amongst the Cnidaria this is not the case. Although the phylogenetic significance of this molecular character is unclear, our analyses do not support the close relationship between Cnidaria and Placozoa suggested by previous studies.

  2. Internal and external relationships of the Cnidaria: implications of primary and predicted secondary structure of the 5'-end of the 23S-like rDNA.

    PubMed Central

    Odorico, D M; Miller, D J

    1997-01-01

    Since both internal (class-level) and external relationships of the Cnidaria remain unclear on the basis of analyses of 18S and (partial) 16S rDNA sequence data, we examined the informativeness of the 5'-end of the 23S-like rDNA. Here we describe analyses of both primary and predicted secondary structure data for this region from the ctenophore Bolinopsis sp., the placozoan Trichoplax adhaerens, the sponge Hymeniacidon heliophila, and representatives of all four cnidarian classes. Primary sequence analyses clearly resolved the Cnidaria from other lower Metazoa, supported sister group relationships between the Scyphozoa and Cubozoa and between the Ctenophora and the Placozoa, and confirmed the basal status of the Anthozoa within the Cnidaria. Additionally, in the ctenophore, placozoan and sponge, non-canonical base pairing is required to maintain the secondary structure of the B12 region, whereas amongst the Cnidaria this is not the case. Although the phylogenetic significance of this molecular character is unclear, our analyses do not support the close relationship between Cnidaria and Placozoa suggested by previous studies. PMID:9061962

  3. Quantification of bioluminescence from the surface to the deep sea demonstrates its predominance as an ecological trait

    NASA Astrophysics Data System (ADS)

    Martini, Séverine; Haddock, Steven H. D.

    2017-04-01

    The capability of animals to emit light, called bioluminescence, is considered to be a major factor in ecological interactions. Because it occurs across diverse taxa, measurements of bioluminescence can be powerful to detect and quantify organisms in the ocean. In this study, 17 years of video observations were recorded by remotely operated vehicles during surveys off the California Coast, from the surface down to 3,900 m depth. More than 350,000 observations are classified for their bioluminescence capability based on literature descriptions. The organisms represented 553 phylogenetic concepts (species, genera or families, at the most precise taxonomic level defined from the images), distributed within 13 broader taxonomic categories. The importance of bioluminescent marine taxa is highlighted in the water column, as we showed that 76% of the observed individuals have bioluminescence capability. More than 97% of Cnidarians were bioluminescent, and 9 of the 13 taxonomic categories were found to be bioluminescent dominant. The percentage of bioluminescent animals is remarkably uniform over depth. Moreover, the proportion of bioluminescent and non-bioluminescent animals within taxonomic groups changes with depth for Ctenophora, Scyphozoa, Chaetognatha, and Crustacea. Given these results, bioluminescence has to be considered an important ecological trait from the surface to the deep-sea.

  4. Jellyfish Stings Trigger Gill Disorders and Increased Mortality in Farmed Sparus aurata (Linnaeus, 1758) in the Mediterranean Sea.

    PubMed

    Bosch-Belmar, Mar; M'Rabet, Charaf; Dhaouadi, Raouf; Chalghaf, Mohamed; Daly Yahia, Mohamed Néjib; Fuentes, Verónica; Piraino, Stefano; Kéfi-Daly Yahia, Ons

    2016-01-01

    Jellyfish are of particular concern for marine finfish aquaculture. In recent years repeated mass mortality episodes of farmed fish were caused by blooms of gelatinous cnidarian stingers, as a consequence of a wide range of hemolytic, cytotoxic, and neurotoxic properties of associated cnidocytes venoms. The mauve stinger jellyfish Pelagia noctiluca (Scyphozoa) has been identified as direct causative agent for several documented fish mortality events both in Northern Europe and the Mediterranean Sea aquaculture farms. We investigated the effects of P. noctiluca envenomations on the gilthead sea bream Sparus aurata by in vivo laboratory assays. Fish were incubated for 8 hours with jellyfish at 3 different densities in 300 l experimental tanks. Gill disorders were assessed by histological analyses and histopathological scoring of samples collected at time intervals from 3 hours to 4 weeks after initial exposure. Fish gills showed different extent and severity of gill lesions according to jellyfish density and incubation time, and long after the removal of jellyfish from tanks. Jellyfish envenomation elicits local and systemic inflammation reactions, histopathology and gill cell toxicity, with severe impacts on fish health. Altogether, these results shows P. noctiluca swarms may represent a high risk for Mediterranean finfish aquaculture farms, generating significant gill damage after only a few hours of contact with farmed S. aurata. Due to the growth of the aquaculture sector and the increased frequency of jellyfish blooms in the coastal waters, negative interactions between stinging jellyfish and farmed fish are likely to increase with the potential for significant economic losses.

  5. Jellyfish Stings Trigger Gill Disorders and Increased Mortality in Farmed Sparus aurata (Linnaeus, 1758) in the Mediterranean Sea

    PubMed Central

    Dhaouadi, Raouf; Chalghaf, Mohamed; Daly Yahia, Mohamed Néjib; Fuentes, Verónica; Piraino, Stefano; Kéfi-Daly Yahia, Ons

    2016-01-01

    Jellyfish are of particular concern for marine finfish aquaculture. In recent years repeated mass mortality episodes of farmed fish were caused by blooms of gelatinous cnidarian stingers, as a consequence of a wide range of hemolytic, cytotoxic, and neurotoxic properties of associated cnidocytes venoms. The mauve stinger jellyfish Pelagia noctiluca (Scyphozoa) has been identified as direct causative agent for several documented fish mortality events both in Northern Europe and the Mediterranean Sea aquaculture farms. We investigated the effects of P. noctiluca envenomations on the gilthead sea bream Sparus aurata by in vivo laboratory assays. Fish were incubated for 8 hours with jellyfish at 3 different densities in 300 l experimental tanks. Gill disorders were assessed by histological analyses and histopathological scoring of samples collected at time intervals from 3 hours to 4 weeks after initial exposure. Fish gills showed different extent and severity of gill lesions according to jellyfish density and incubation time, and long after the removal of jellyfish from tanks. Jellyfish envenomation elicits local and systemic inflammation reactions, histopathology and gill cell toxicity, with severe impacts on fish health. Altogether, these results shows P. noctiluca swarms may represent a high risk for Mediterranean finfish aquaculture farms, generating significant gill damage after only a few hours of contact with farmed S. aurata. Due to the growth of the aquaculture sector and the increased frequency of jellyfish blooms in the coastal waters, negative interactions between stinging jellyfish and farmed fish are likely to increase with the potential for significant economic losses. PMID:27100175

  6. Evolutionary Diversification of Banded Tube-Dwelling Anemones (Cnidaria; Ceriantharia; Isarachnanthus) in the Atlantic Ocean

    PubMed Central

    Stampar, Sergio N.; Maronna, Maximiliano M.; Vermeij, Mark J. A.; Silveira, Fabio L. d.; Morandini, André C.

    2012-01-01

    The use of molecular data for species delimitation in Anthozoa is still a very delicate issue. This is probably due to the low genetic variation found among the molecular markers (primarily mitochondrial) commonly used for Anthozoa. Ceriantharia is an anthozoan group that has not been tested for genetic divergence at the species level. Recently, all three Atlantic species described for the genus Isarachnanthus of Atlantic Ocean, were deemed synonyms based on morphological simmilarities of only one species: Isarachnanthus maderensis. Here, we aimed to verify whether genetic relationships (using COI, 16S, ITS1 and ITS2 molecular markers) confirmed morphological affinities among members of Isarachnanthus from different regions across the Atlantic Ocean. Results from four DNA markers were completely congruent and revealed that two different species exist in the Atlantic Ocean. The low identification success and substantial overlap between intra and interspecific COI distances render the Anthozoa unsuitable for DNA barcoding, which is not true for Ceriantharia. In addition, genetic divergence within and between Ceriantharia species is more similar to that found in Medusozoa (Hydrozoa and Scyphozoa) than Anthozoa and Porifera that have divergence rates similar to typical metazoans. The two genetic species could also be separated based on micromorphological characteristics of their cnidomes. Using a specimen of Isarachnanthus bandanensis from Pacific Ocean as an outgroup, it was possible to estimate the minimum date of divergence between the clades. The cladogenesis event that formed the species of the Atlantic Ocean is estimated to have occured around 8.5 million years ago (Miocene) and several possible speciation scenarios are discussed. PMID:22815928

  7. Evolutionary diversification of banded tube-dwelling anemones (Cnidaria; Ceriantharia; Isarachnanthus) in the Atlantic Ocean.

    PubMed

    Stampar, Sergio N; Maronna, Maximiliano M; Vermeij, Mark J A; Silveira, Fabio L d; Morandini, André C

    2012-01-01

    The use of molecular data for species delimitation in Anthozoa is still a very delicate issue. This is probably due to the low genetic variation found among the molecular markers (primarily mitochondrial) commonly used for Anthozoa. Ceriantharia is an anthozoan group that has not been tested for genetic divergence at the species level. Recently, all three Atlantic species described for the genus Isarachnanthus of Atlantic Ocean, were deemed synonyms based on morphological simmilarities of only one species: Isarachnanthus maderensis. Here, we aimed to verify whether genetic relationships (using COI, 16S, ITS1 and ITS2 molecular markers) confirmed morphological affinities among members of Isarachnanthus from different regions across the Atlantic Ocean. Results from four DNA markers were completely congruent and revealed that two different species exist in the Atlantic Ocean. The low identification success and substantial overlap between intra and interspecific COI distances render the Anthozoa unsuitable for DNA barcoding, which is not true for Ceriantharia. In addition, genetic divergence within and between Ceriantharia species is more similar to that found in Medusozoa (Hydrozoa and Scyphozoa) than Anthozoa and Porifera that have divergence rates similar to typical metazoans. The two genetic species could also be separated based on micromorphological characteristics of their cnidomes. Using a specimen of Isarachnanthus bandanensis from Pacific Ocean as an outgroup, it was possible to estimate the minimum date of divergence between the clades. The cladogenesis event that formed the species of the Atlantic Ocean is estimated to have occured around 8.5 million years ago (Miocene) and several possible speciation scenarios are discussed.

  8. Genetic diversity of populations and clones of Rhopilema esculentum in China based on AFLP analysis

    NASA Astrophysics Data System (ADS)

    Qiao, Hongjin; Liu, Xiangquan; Zhang, Xijia; Jiang, Haibin; Wang, Jiying; Zhang, Limin

    2013-03-01

    Amplified fragment length polymorphisms (AFLP) markers were developed to assess the genetic variation of populations and clones of Rhopilema esculentum Kishinouye (Scyphozoa, Rhizostomatidae). One hundred and seventy-nine loci from 56 individuals of two hatchery populations and two wild populations were genotyped with five primer combinations. The polymorphic ratio, Shannon's diversity index and average heterozygosity were 70.3%, 0.346 and 0.228 for the white hatchery population, 74.3%, 0.313, and 0.201 for the red hatchery population, 79.3%, 0.349, and 0.224 for the Jiangsu wild population, and 74.9%, 0.328 and 0.210 for the Penglai wild population, respectively. Thus, all populations had a relatively high level of genetic diversity. A specific band was identified that could separate the white from the red hatchery population. There was 84.85% genetic differentiation within populations. Individual cluster analysis using unweighted pair-group method with arithmetic mean (UPGMA) suggested that hatchery populations and wild populations could be divided. For the hatchery populations, the white and red populations clustered separately; however, for the wild populations, Penglai and Jiangsu populations clustered together. The genetic diversity at the clone level was also determined. Our data suggest that there are relatively high genetic diversities within populations but low genetic differentiation between populations, which may be related to the long-term use of germplasm resources from Jiangsu Province for artificial seeding and releasing. These findings will benefit the artificial seeding and conservation of the germplasm resources.

  9. Inbreeding and genetic diversity analysis in a hatchery release population and clones of Rhopilema esculentum based on microsatellite markers

    NASA Astrophysics Data System (ADS)

    Tian, Tao; Chen, Zaizhong; Wang, Mosang; Hu, Yulong; Wang, Weiji

    2016-07-01

    Ten microsatellite markers were used to analyze the levels of genetic diversity and inbreeding in a hatchery release population of Rhopilema esculentum Kishinouye (Scyphozoa: Rhizostomatidae). A total of 85 alleles were detected in 600 individuals. Within-population levels of observed (H o) and expected (H e) heterozygosity ranged from 0.152 to 0.839 (mean=0.464) and from 0.235 to 0.821 (mean=0.618), respectively. The polymorphism information content (PIC) of each marker ranged from 0.207 to 0.795 with an average of 0.580, indicating that the hatchery population maintained a high level of genetic diversity. Inbreeding levels were estimated in the hatchery population and the inbreeding coefficient was 0.203. This result revealed that a certain level of inbreeding occurred within the population. Meanwhile, we also determined genetic diversity at the clone level. Several polyps from the same scyphistomae were genotyped at the ten microsatellite loci and there was virtually no difference in their genotypes. Furthermore, we calculated the probabilities of exclusion. When both parents were known, the average exclusion probability of ten loci was 99.99%. Our data suggest that the ten microsatellite markers can not only be used to analyze the identity of individuals but they can also be applied to parentage identification. Our research provides a theoretical basis and technical support for genetic diversity detection and reasonable selection of R. esculentum hatchery populations. These findings support the use of releasing studies and conservation of R. esculentum germplasm resources.

  10. DNA Barcoding the Medusozoa using mtCOI

    NASA Astrophysics Data System (ADS)

    Ortman, Brian D.; Bucklin, Ann; Pagès, Francesc; Youngbluth, Marsh

    2010-12-01

    The Medusozoa are a clade within the Cnidaria comprising the classes Hydrozoa, Scyphozoa, and Cubozoa. Identification of medusozoan species is challenging, even for taxonomic experts, due to their fragile forms and complex, morphologically-distinct life history stages. In this study 231 sequences for a portion of the mitochondrial Cytochrome Oxidase I (mtCOI) gene were obtained from 95 species of Medusozoans including; 84 hydrozoans (61 siphonophores, eight anthomedusae, four leptomedusae, seven trachymedusae, and four narcomedusae), 10 scyphozoans (three coronatae, four semaeostomae, two rhizostomae, and one stauromedusae), and one cubozoan. This region of mtCOI has been used as a DNA barcode (i.e., a molecular character for species recognition and discrimination) for a diverse array of taxa, including some Cnidaria. Kimura 2-parameter (K2P) genetic distances between sequence variants within species ranged from 0 to 0.057 (mean 0.013). Within the 13 genera for which multiple species were available, K2P distance between congeneric species ranged from 0.056 to 0.381. A cluster diagram generated by Neighbor Joining (NJ) using K2P distances reliably clustered all barcodes of the same species with ≥99% bootstrap support, ensuring accurate identification of species. Intra- and inter-specific variation of the mtCOI gene for the Medusozoa are appropriate for this gene to be used as a DNA barcode for species-level identification, but not for phylogenetic analysis or taxonomic classification of unknown sequences at higher taxonomic levels. This study provides a set of molecular tools that can be used to address questions of speciation, biodiversity, life-history, and population boundaries in the Medusozoa.

  11. Protective Effect of Tetracycline against Dermal Toxicity Induced by Jellyfish Venom

    PubMed Central

    Kang, Changkeun; Jin, Yeung Bae; Kwak, Jeongsoo; Jung, Hongseok; Yoon, Won Duk; Yoon, Tae-Jin; Kim, Jong-Shu; Kim, Euikyung

    2013-01-01

    Background Previously, we have reported that most, if not all, of the Scyphozoan jellyfish venoms contain multiple components of metalloproteinases, which apparently linked to the venom toxicity. Further, it is also well known that there is a positive correlation between the inflammatory reaction of dermal tissues and their tissue metalloproteinase activity. Based on these, the use of metalloproteinase inhibitors appears to be a promising therapeutic alternative for the treatment of jellyfish envenomation. Methodology and Principal Findings Tetracycline (a metalloproteinase inhibitor) has been examined for its activity to reduce or prevent the dermal toxicity induced by Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom (NnV) using in vitro and in vivo models. HaCaT (human keratinocyte) and NIH3T3 (mouse fibroblast) incubated with NnV showed decreases in cell viability, which is associated with the inductions of metalloproteinase-2 and -9. This result suggests that the use of metalloproteinase inhibitors, such as tetracycline, may prevent the jellyfish venom-mediated local tissue damage. In vivo experiments showed that comparing with NnV-alone treatment, tetracycline pre-mixed NnV demonstrated a significantly reduced progression of dermal toxicity upon the inoculation onto rabbit skin. Conclusions/Significance It is believed that there has been no previous report on the therapeutic agent of synthetic chemical origin for the treatment of jellyfish venom-induced dermonecrosis based on understanding its mechanism of action except the use of antivenom treatment. Furthermore, the current study, for the first time, has proposed a novel mechanism-based therapeutic intervention for skin damages caused by jellyfish stings. PMID:23536767

  12. Evolution of linear mitochondrial genomes in medusozoan cnidarians.

    PubMed

    Kayal, Ehsan; Bentlage, Bastian; Collins, Allen G; Kayal, Mohsen; Pirro, Stacy; Lavrov, Dennis V

    2012-01-01

    In nearly all animals, mitochondrial DNA (mtDNA) consists of a single circular molecule that encodes several subunits of the protein complexes involved in oxidative phosphorylation as well as part of the machinery for their expression. By contrast, mtDNA in species belonging to Medusozoa (one of the two major lineages in the phylum Cnidaria) comprises one to several linear molecules. Many questions remain on the ubiquity of linear mtDNA in medusozoans and the mechanisms responsible for its evolution, replication, and transcription. To address some of these questions, we determined the sequences of nearly complete linear mtDNA from 24 species representing all four medusozoan classes: Cubozoa, Hydrozoa, Scyphozoa, and Staurozoa. All newly determined medusozoan mitochondrial genomes harbor the 17 genes typical for cnidarians and map as linear molecules with a high degree of gene order conservation relative to the anthozoans. In addition, two open reading frames (ORFs), polB and ORF314, are identified in cubozoan, schyphozoan, staurozoan, and trachyline hydrozoan mtDNA. polB belongs to the B-type DNA polymerase gene family, while the product of ORF314 may act as a terminal protein that binds telomeres. We posit that these two ORFs are remnants of a linear plasmid that invaded the mitochondrial genomes of the last common ancestor of Medusozoa and are responsible for its linearity. Hydroidolinan hydrozoans have lost the two ORFs and instead have duplicated cox1 at each end of their mitochondrial chromosome(s). Fragmentation of mtDNA occurred independently in Cubozoa and Hydridae (Hydrozoa, Hydroidolina). Our broad sampling allows us to reconstruct the evolutionary history of linear mtDNA in medusozoans.

  13. Evolution of Linear Mitochondrial Genomes in Medusozoan Cnidarians

    PubMed Central

    Kayal, Ehsan; Bentlage, Bastian; Collins, Allen G.; Pirro, Stacy; Lavrov, Dennis V.

    2012-01-01

    In nearly all animals, mitochondrial DNA (mtDNA) consists of a single circular molecule that encodes several subunits of the protein complexes involved in oxidative phosphorylation as well as part of the machinery for their expression. By contrast, mtDNA in species belonging to Medusozoa (one of the two major lineages in the phylum Cnidaria) comprises one to several linear molecules. Many questions remain on the ubiquity of linear mtDNA in medusozoans and the mechanisms responsible for its evolution, replication, and transcription. To address some of these questions, we determined the sequences of nearly complete linear mtDNA from 24 species representing all four medusozoan classes: Cubozoa, Hydrozoa, Scyphozoa, and Staurozoa. All newly determined medusozoan mitochondrial genomes harbor the 17 genes typical for cnidarians and map as linear molecules with a high degree of gene order conservation relative to the anthozoans. In addition, two open reading frames (ORFs), polB and ORF314, are identified in cubozoan, schyphozoan, staurozoan, and trachyline hydrozoan mtDNA. polB belongs to the B-type DNA polymerase gene family, while the product of ORF314 may act as a terminal protein that binds telomeres. We posit that these two ORFs are remnants of a linear plasmid that invaded the mitochondrial genomes of the last common ancestor of Medusozoa and are responsible for its linearity. Hydroidolinan hydrozoans have lost the two ORFs and instead have duplicated cox1 at each end of their mitochondrial chromosome(s). Fragmentation of mtDNA occurred independently in Cubozoa and Hydridae (Hydrozoa, Hydroidolina). Our broad sampling allows us to reconstruct the evolutionary history of linear mtDNA in medusozoans. PMID:22113796

  14. [Reason to split the genus Aurelia. Mesoglein from two populations differ].

    PubMed

    Kotova, A V; Podgornaia, O I; Adonin, L S

    2015-01-01

    The medusa, Aurelia aurita (Scyphozoa, Cnidaria), is considered to be a cosmopolitan species with a worldwide distribution in most seas from the poles to the tropics. Cnidarian is thought to possess two tissue layers: endoderm (gastroderm) and ectoderm, which are separated by huge mesoglea in medusa. The basic morphology of medusa is similar in different populations. Previously we have determined a new protein "mesoglein" as one of the main components of mesoglea. Deduced amino acid sequence of mesoglein contains Zona Pellucida (ZP) domain. In this paper, we have comparied of mesoglein and its gene in medusa from three habitats (White Sea (WsA), Black Sea (BsA), Japonic Sea (JsA)). The set of the mesoglea protein bands after SDS-PAGE is similar in all samples. Nevertheless, JsA mesogleins' M(r) is 53-55 kDa, while WsA and BsA mesogleins have M(r) of 47 kDa. Antibodies raised against WsA mesoglein recognize only mesogleins with M(r) of 47 kDa, but not 53-55 kDa, both on immunoblot and immunocytochemistry. Mesogleal cells and elastic fibrils are stained intensively in the mesoglea both from WsA and BsA but not from JsA. The possibility of gene divergency was checked by PCR with primers specific for WsA mesoglein gene. PCR products of expected length obtained on polyA-cDNA template from mesogleal cells of WsA and BsA medusa but not on cDNA of JsA medusa. Our results evidence that there are two different species in genus Aurelia: Aurelia aurita inhabits White and Black Seas while Aurelia sp. inhabits Japonic Sea. This is consistent with findings of other recept molecular biological studies.

  15. Inbreeding and genetic diversity analysis in a hatchery release population and clones of Rhopilema esculentum based on microsatellite markers

    NASA Astrophysics Data System (ADS)

    Tian, Tao; Chen, Zaizhong; Wang, Mosang; Hu, Yulong; Wang, Weiji

    2017-05-01

    Ten microsatellite markers were used to analyze the levels of genetic diversity and inbreeding in a hatchery release population of Rhopilema esculentum Kishinouye (Scyphozoa: Rhizostomatidae). A total of 85 alleles were detected in 600 individuals. Within-population levels of observed ( H o) and expected ( H e) heterozygosity ranged from 0.152 to 0.839 (mean=0.464) and from 0.235 to 0.821 (mean=0.618), respectively. The polymorphism information content (PIC) of each marker ranged from 0.207 to 0.795 with an average of 0.580, indicating that the hatchery population maintained a high level of genetic diversity. Inbreeding levels were estimated in the hatchery population and the inbreeding coefficient was 0.203. This result revealed that a certain level of inbreeding occurred within the population. Meanwhile, we also determined genetic diversity at the clone level. Several polyps from the same scyphistomae were genotyped at the ten microsatellite loci and there was virtually no difference in their genotypes. Furthermore, we calculated the probabilities of exclusion. When both parents were known, the average exclusion probability of ten loci was 99.99%. Our data suggest that the ten microsatellite markers can not only be used to analyze the identity of individuals but they can also be applied to parentage identification. Our research provides a theoretical basis and technical support for genetic diversity detection and reasonable selection of R. esculentum hatchery populations. These findings support the use of releasing studies and conservation of R. esculentum germplasm resources.

  16. Gelatinous zooplankton in the Belgian part of the North Sea and the adjacent Schelde estuary: Spatio-temporal distribution patterns and population dynamics

    NASA Astrophysics Data System (ADS)

    Vansteenbrugge, Lies; Van Regenmortel, Tina; De Troch, Marleen; Vincx, Magda; Hostens, Kris

    2015-03-01

    Many ocean ecosystems are thought to be heading towards a dominance of gelatinous organisms. However, gelatinous zooplankton has been largely understudied and the absence of quantitative long-term data for the studied area impedes drawing conclusions on potential increasing densities. This study gives a comprehensive overview of the spatio-temporal distribution patterns of gelatinous zooplankton in terms of diversity and density in the Belgian part of the North Sea and the adjacent Schelde estuary, based on monthly and seasonal samples between March 2011 and February 2012. Three Scyphozoa, three Ctenophora and 27 Hydrozoa taxa were identified, including three non-indigenous species: Mnemiopsis leidyi, Nemopsis bachei and Lovenella assimilis. In general, one gelatinous zooplankton assemblage was found across locations and seasons. Average gelatinous zooplankton densities reached up to 18 ind·m-3 near the coast, gradually declining towards the open sea. In the brackish Schelde estuary, average densities remained below 3 ind·m-3. Highest gelatinous zooplankton densities were recorded in summer and autumn. Overall, hydromedusae were the most important group both in terms of diversity and density. The ctenophore Pleurobrachia pileus and the hydromedusa Clytia sp. were present in every season and at every location. Gelatinous zooplankton densities never outnumbered the non-gelatinous zooplankton densities recorded from the WP3 samples. The spatial and temporal distribution patterns seemed to be mainly driven by temperature (season) and salinity (location). Other environmental parameters including (larger) non-gelatinous zooplankton densities (as an important food source) were not retained in the most parsimonious DistLM model.In terms of population dynamics, Beroe sp. seemed to follow the three reproductive cycles of its prey P. pileus and the presence of M. leidyi, which were abundant in a broad size spectrum in summer and autumn. In general, gelatinous zooplankton