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Yonezawa R, Hayashi K, Oyama H, Yoshitake K, Sato S, Senevirathna JDM, Smith AR, Okabe T, Suo R, Kinoshita S, Takatani T, Arakawa O, Asakawa S, Itoi S. Tissue Localization of Tetrodotoxin in the Flatworm Planocera multitentaculata (Platyhelminthes: Polycladida). MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2024:10.1007/s10126-024-10332-w. [PMID: 38861110 DOI: 10.1007/s10126-024-10332-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2024] [Accepted: 06/03/2024] [Indexed: 06/12/2024]
Abstract
Tetrodotoxin (TTX), a pufferfish toxin, is a highly potent neurotoxin that has been found in a wide variety of animals. The TTX-bearing flatworm Planocera multitentaculata possesses a large amount of TTX and is considered responsible for the toxification of TTX-bearing animals such as pufferfish (Takifugu and Chelonodon) and the toxic goby Yongeichthys criniger. However, the mechanism underlying TTX accumulation in flatworms remains unclear. Previous studies have been limited to identifying the distribution of TTX in multiple organs, such as the digestive organs, genital parts, and the remaining tissues of flatworms. Here, we performed liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis and immunohistochemical staining using a monoclonal anti-TTX antibody to elucidate the detailed localization of TTX in the tissues and organs of the flatworm P. multitentaculata. Immunohistochemical staining for P. multitentaculata showed that TTX-specific signals were detected not only in the ovaries and pharynx but also in many other tissues and organs, whereas no signal was detected in the brain, Lang's vesicle, and genitalia. In addition, combined with LC-MS/MS analysis, it was revealed for the first time that TTX accumulates in high concentrations in the basement membrane and epidermis. These findings robustly support the hypotheses of "TTX utilization protection from predators."
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Affiliation(s)
- Ryo Yonezawa
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Kentaro Hayashi
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Hikaru Oyama
- College of Bioresource Sciences, Nihon University, Kanagawa, Japan
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8566, Japan
| | - Kazutoshi Yoshitake
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Soshi Sato
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Jayan Duminda M Senevirathna
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Animal Science, Faculty of Animal Science and Export Agriculture, Uva Wellassa University, Badulla, 90000, Sri Lanka
| | - Ashley R Smith
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Taiki Okabe
- College of Bioresource Sciences, Nihon University, Kanagawa, Japan
- Niigata Prefectural Kaiyo High School, Itoigawa, Niigata, 949-1352, Japan
| | - Rei Suo
- College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Shigeharu Kinoshita
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Tomohiro Takatani
- Graduate School of Integrated Science and Technology, Nagasaki University, Nagasaki, 852-8521, Japan
| | - Osamu Arakawa
- Graduate School of Integrated Science and Technology, Nagasaki University, Nagasaki, 852-8521, Japan
| | - Shuichi Asakawa
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.
| | - Shiro Itoi
- College of Bioresource Sciences, Nihon University, Kanagawa, Japan.
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Kim JH, Kim DW, Cho SR, Lee KJ, Mok JS. Tetrodotoxin and the Geographic Distribution of the Blue-Lined Octopus Hapalochlaena fasciata on the Korean Coast. Toxins (Basel) 2023; 15:toxins15040279. [PMID: 37104217 PMCID: PMC10145357 DOI: 10.3390/toxins15040279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 04/06/2023] [Accepted: 04/07/2023] [Indexed: 04/28/2023] Open
Abstract
The genus Hapalochlaena, including the blue-lined octopus Hapalochlaena fasciata (H. fasciata), is highly toxic. Venomous, blue-lined octopuses were recently found in Korea, but their toxicity, toxin composition, and distribution remain largely unknown. Here we estimated the geographic distribution of the organisms along the Korean coast and clarified their toxicity. Tetrodotoxin (TTX) was present in all three specimens of H. fasciata examined, although the toxicity varied largely between individuals. The mean TTX concentration in the whole body of the three specimens was 6.5 ± 2.2 μg/g (range 3.3-8.5 μg/g). Among the body parts examined, the salivary glands exhibited the highest concentration (22.4 ± 9.7 μg/g). From 2012 to 2021, 26 individuals were obtained nearly every month from different regions of the Korean coast. A non-fatal case of a blue-lined octopus bite was reported along the Korean coast in June 2015. This is the first report on the widespread distribution of blue-lined octopuses on the Korean coast and TTX detection. The widespread distribution of the TTX-bearing H. fasciata along the Korean coast within the temperate zone indicates that the species may soon become a serious health issue in Korea. The toxicity of this species is also a potentially significant human health risk.
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Affiliation(s)
- Ji-Hoe Kim
- Research & Development Planning and Coordination Department, National Institute of Fisheries Science, Busan 46083, Republic of Korea
| | - Dong-Wook Kim
- Food Safety and Processing Research Division, National Institute of Fisheries Science, Busan 46083, Republic of Korea
| | - Sung-Rae Cho
- Southeast Sea Fisheries Research Institute, National Institute of Fisheries Science, Tongyeong 53085, Republic of Korea
| | - Ka-Jeong Lee
- Food Safety and Processing Research Division, National Institute of Fisheries Science, Busan 46083, Republic of Korea
| | - Jong-Soo Mok
- Food Safety and Processing Research Division, National Institute of Fisheries Science, Busan 46083, Republic of Korea
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Tetrodotoxin Profiles in Xanthid Crab Atergatis floridus and Blue-Lined Octopus Hapalochlaena cf. fasciata from the Same Site in Nagasaki, Japan. Toxins (Basel) 2023; 15:toxins15030193. [PMID: 36977084 PMCID: PMC10052739 DOI: 10.3390/toxins15030193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 03/08/2023] Open
Abstract
The xanhid crab Atergatis floridus and the blue-lined octopus Hapalochlaena cf. fasciata have long been known as TTX-bearing organisms. It has been speculated that the TTX possessed by both organisms is exogenously toxic through the food chain, since they are reported to have geographic and individual differences. The source and supply chain of TTX for both of these organisms, however, remain unclear. On the other hand, since crabs are one of the preferred prey of octopuses, we focused our attention on the relationship between the two species living in the same site. The aim of this study was to determine TTX concentrations and TTX profiles of A. floridus and H. cf. fasciata, collected simultaneously in the same site, and examine the relationship between them. Although there were individual differences in the TTX concentration in both A. floridus and H. cf. fasciata, the toxin components commonly contained 11-norTTX-6(S)-ol in addition to TTX as the major components, with 4-epiTTX, 11-deoxyTTX, and 4,9-anhydroTTX as the minor components. The results suggest that octopuses and crabs in this site acquire TTX from common prey, including TTX-producing bacteria and/or may have a predator–prey relationship.
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Oyama H, Ito M, Suo R, Goto-Inoue N, Morisasa M, Mori T, Sugita H, Mori T, Nakahigashi R, Adachi M, Nishikawa T, Itoi S. Changes in Tissue Distribution of Tetrodotoxin and Its Analogues in Association with Maturation in the Toxic Flatworm, Planocera multitentaculata. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2022; 24:1158-1167. [PMID: 36322281 DOI: 10.1007/s10126-022-10179-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 10/20/2022] [Indexed: 06/16/2023]
Abstract
The toxic flatworm, Planocera multitentaculata, possesses highly concentrated tetrodotoxin (TTX), also known as pufferfish toxin, throughout its life cycle, including the egg and larval stages. Additionally, TTX analogues, 5,6,11-trideoxyTTX and 11-norTTX-6(S)-ol, have also been detected in the flatworm. The high concentration of TTX in the eggs and larvae appears to be for protection against predation, and 11-norTTX-6(S)-ol in the pharyngeal tissue in the adults is likely used to sedate or kill prey during predation. However, information on the role of 5,6,11-trideoxyTTX, a potential important biosynthetic intermediate of TTX, in the toxic flatworm is lacking. Here, we aimed to determine the region of localization of TTX and its analogues in the flatworm body, understand their pharmacokinetics during maturation, and speculate on their function. Flatworm specimens in four stages of maturity, namely juvenile, mating, spawning, and late spawning, were subjected to LC-MS/MS analysis, using the pharyngeal tissue, oocytes in seminal receptacle, sperm, and tissue from 12 other sites. Although TTX was consistently high in the pharyngeal tissue throughout maturation, it was extremely high in the oocytes during the spawning period. Meanwhile, 5,6,11-trideoxyTTX was almost undetectable in the pharyngeal part throughout the maturation but was very abundant in the oocytes during spawning. 11-norTTX-6(S)-ol consistently localized in the pharyngeal tissue. Although the localization of TTX and its analogues was approximately consistent with the MS imaging data, TTX and 11-norTTX-6(S)-ol were found to be highly localized in the parenchyma surrounding the pharynx, which suggests the parenchyma is involved in the accumulation and production of TTXs.
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Affiliation(s)
- Hikaru Oyama
- Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa, 252-0880, Japan
| | - Masaaki Ito
- Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa, 252-0880, Japan
| | - Rei Suo
- Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa, 252-0880, Japan
| | - Naoko Goto-Inoue
- Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa, 252-0880, Japan
| | - Mizuki Morisasa
- Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa, 252-0880, Japan
| | - Tsukasa Mori
- Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa, 252-0880, Japan
| | - Haruo Sugita
- Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa, 252-0880, Japan
| | - Tetsushi Mori
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan
| | - Ryota Nakahigashi
- Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Aichi, 464-8601, Japan
| | - Masaatsu Adachi
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai, Miyagi, 980-8578, Japan
| | - Toshio Nishikawa
- Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Aichi, 464-8601, Japan
| | - Shiro Itoi
- Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa, 252-0880, Japan.
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Melnikova DI, Magarlamov TY. An Overview of the Anatomical Distribution of Tetrodotoxin in Animals. Toxins (Basel) 2022; 14:toxins14080576. [PMID: 36006238 PMCID: PMC9412668 DOI: 10.3390/toxins14080576] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/15/2022] [Accepted: 08/19/2022] [Indexed: 11/23/2022] Open
Abstract
Tetrodotoxin (TTX), a potent paralytic sodium channel blocker, is an intriguing marine toxin. Widely distributed in nature, TTX has attracted attention in various scientific fields, from biomedical studies to environmental safety concerns. Despite a long history of studies, many issues concerning the biosynthesis, origin, and spread of TTX in animals and ecosystems remain. This review aims to summarize the current knowledge on TTX circulation inside TTX-bearing animal bodies. We focus on the advances in TTX detection at the cellular and subcellular levels, providing an expanded picture of intra-organismal TTX migration mechanisms. We believe that this review will help address the gaps in the understanding of the biological function of TTX and facilitate the development of further studies involving TTX-bearing animals.
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van Thiel J, Khan MA, Wouters RM, Harris RJ, Casewell NR, Fry BG, Kini RM, Mackessy SP, Vonk FJ, Wüster W, Richardson MK. Convergent evolution of toxin resistance in animals. Biol Rev Camb Philos Soc 2022; 97:1823-1843. [PMID: 35580905 PMCID: PMC9543476 DOI: 10.1111/brv.12865] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 04/22/2022] [Accepted: 04/26/2022] [Indexed: 12/17/2022]
Abstract
Convergence is the phenomenon whereby similar phenotypes evolve independently in different lineages. One example is resistance to toxins in animals. Toxins have evolved many times throughout the tree of life. They disrupt molecular and physiological pathways in target species, thereby incapacitating prey or deterring a predator. In response, molecular resistance has evolved in many species exposed to toxins to counteract their harmful effects. Here, we review current knowledge on the convergence of toxin resistance using examples from a wide range of toxin families. We explore the evolutionary processes and molecular adaptations driving toxin resistance. However, resistance adaptations may carry a fitness cost if they disrupt the normal physiology of the resistant animal. Therefore, there is a trade‐off between maintaining a functional molecular target and reducing toxin susceptibility. There are relatively few solutions that satisfy this trade‐off. As a result, we see a small set of molecular adaptations appearing repeatedly in diverse animal lineages, a phenomenon that is consistent with models of deterministic evolution. Convergence may also explain what has been called ‘autoresistance’. This is often thought to have evolved for self‐protection, but we argue instead that it may be a consequence of poisonous animals feeding on toxic prey. Toxin resistance provides a unique and compelling model system for studying the interplay between trophic interactions, selection pressures and the molecular mechanisms underlying evolutionary novelties.
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Affiliation(s)
- Jory van Thiel
- Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Muzaffar A Khan
- Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Roel M Wouters
- Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Richard J Harris
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia, 4072, Australia
| | - Nicholas R Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K
| | - Bryan G Fry
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia, 4072, Australia
| | - R Manjunatha Kini
- Department of Biological Sciences, National University of Singapore, Singapore, 117558, Singapore.,Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Singapore.,Department of Biochemistry, Medical College of Virginia, Virginia Commonwealth University, Richmond, VA, 23298, U.S.A
| | - Stephen P Mackessy
- School of Biological Sciences, University of Northern Colorado, Greeley, CO, 80639-0017, U.S.A
| | - Freek J Vonk
- Naturalis Biodiversity Center, Darwinweg 2, 2333 CR Leiden, The Netherlands.,Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands
| | - Wolfgang Wüster
- Molecular Ecology and Fisheries Genetics Laboratory, School of Natural Sciences, Bangor University, Bangor, LL57 2UW, U.K
| | - Michael K Richardson
- Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
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Katikou P, Gokbulut C, Kosker AR, Campàs M, Ozogul F. An Updated Review of Tetrodotoxin and Its Peculiarities. Mar Drugs 2022; 20:md20010047. [PMID: 35049902 PMCID: PMC8780202 DOI: 10.3390/md20010047] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/28/2021] [Accepted: 12/30/2021] [Indexed: 12/19/2022] Open
Abstract
Tetrodotoxin (TTX) is a crystalline, weakly basic, colorless organic substance and is one of the most potent marine toxins known. Although TTX was first isolated from pufferfish, it has been found in numerous other marine organisms and a few terrestrial species. Moreover, tetrodotoxication is still an important health problem today, as TTX has no known antidote. TTX poisonings were most commonly reported from Japan, Thailand, and China, but today the risk of TTX poisoning is spreading around the world. Recent studies have shown that TTX-containing fish are being found in other regions of the Pacific and in the Indian Ocean, as well as the Mediterranean Sea. This review aims to summarize pertinent information available to date on the structure, origin, distribution, mechanism of action of TTX and analytical methods used for the detection of TTX, as well as on TTX-containing organisms, symptoms of TTX poisoning, and incidence worldwide.
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Affiliation(s)
- Panagiota Katikou
- Ministry of Rural Development and Food, Directorate of Research, Innovation and Education, Hapsa & Karatasou 1, 54626 Thessaloniki, Greece
- Correspondence: (P.K.); (F.O.)
| | - Cengiz Gokbulut
- Department of Pharmacology, Faculty of Medicine, Balikesir University, Balikesir 10145, Turkey;
| | - Ali Rıza Kosker
- Department of Seafood Processing Technology, Faculty of Fisheries, Cukurova University, Adana 01330, Turkey;
| | - Mònica Campàs
- IRTA, Ctra Poble Nou km 5.5, 43540 Sant Carles de la Ràpita, Spain;
| | - Fatih Ozogul
- Department of Seafood Processing Technology, Faculty of Fisheries, Cukurova University, Adana 01330, Turkey;
- Correspondence: (P.K.); (F.O.)
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Intrabody Tetrodotoxin Distribution and Possible Hypothesis for Its Migration in Ribbon Worms Cephalothrix cf. simula (Palaeonemertea, Nemertea). Mar Drugs 2021; 19:md19090494. [PMID: 34564156 PMCID: PMC8465930 DOI: 10.3390/md19090494] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/17/2021] [Accepted: 08/26/2021] [Indexed: 12/13/2022] Open
Abstract
Tetrodotoxin (TTX) is a potent neurotoxin found in many marine and terrestrial animals, but only a few species, such as the ribbon worms of the genus Cephalothrix, accumulate it in extremely high concentrations. The intrabody distribution of TTX in highly toxic organisms is of great interest because it helps researchers to understand the pathways by which the toxin migrates, accumulates, and functions in tissues. Using immunohistochemistry with anti-TTX antibodies, the authors of this study investigated the toxin's distribution inside the organs, tissues, and cells of Cephalothrix cf. simula. The cell types of TTX-positive tissues were identified by light microscopy. The main sites of TTX accumulation occurred in the secretory cells of the integuments, the microvilli of the epidermal ciliary cells, cephalic glands, the glandular epithelia of the proboscises, the enterocytes of the digestive systems, and nephridia. Obtained data suggest the toxin migrates from the digestive system through blood vessels to target organs. TTX is excreted from the body through the nephridia and mucus of epidermal cells.
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9
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Natural Products in Polyclad Flatworms. Mar Drugs 2021; 19:md19020047. [PMID: 33494164 PMCID: PMC7909797 DOI: 10.3390/md19020047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 01/14/2021] [Accepted: 01/16/2021] [Indexed: 12/22/2022] Open
Abstract
Marine invertebrates are promising sources of novel bioactive secondary metabolites, and organisms like sponges, ascidians and nudibranchs are characterised by possessing potent defensive chemicals. Animals that possess chemical defences often advertise this fact with aposematic colouration that potential predators learn to avoid. One seemingly defenceless group that can present bright colouration patterns are flatworms of the order Polycladida. Although members of this group have typically been overlooked due to their solitary and benthic nature, recent studies have isolated the neurotoxin tetrodotoxin from these mesopredators. This review considers the potential of polyclads as potential sources of natural products and reviews what is known of the activity of the molecules found in these animals. Considering the ecology and diversity of polyclads, only a small number of species from both suborders of Polycladida, Acotylea and Cotylea have been investigated for natural products. As such, confirming assumptions as to which species are in any sense toxic or if the compounds they use are biosynthesised, accumulated from food or the product of symbiotic bacteria is difficult. However, further research into the group is suggested as these animals often display aposematic colouration and are known to prey on invertebrates rich in bioactive secondary metabolites.
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Whitelaw BL, Cooke IR, Finn J, da Fonseca RR, Ritschard EA, Gilbert MTP, Simakov O, Strugnell JM. Adaptive venom evolution and toxicity in octopods is driven by extensive novel gene formation, expansion, and loss. Gigascience 2020; 9:giaa120. [PMID: 33175168 PMCID: PMC7656900 DOI: 10.1093/gigascience/giaa120] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/10/2020] [Accepted: 10/06/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Cephalopods represent a rich system for investigating the genetic basis underlying organismal novelties. This diverse group of specialized predators has evolved many adaptations including proteinaceous venom. Of particular interest is the blue-ringed octopus genus (Hapalochlaena), which are the only octopods known to store large quantities of the potent neurotoxin, tetrodotoxin, within their tissues and venom gland. FINDINGS To reveal genomic correlates of organismal novelties, we conducted a comparative study of 3 octopod genomes, including the Southern blue-ringed octopus (Hapalochlaena maculosa). We present the genome of this species and reveal highly dynamic evolutionary patterns at both non-coding and coding organizational levels. Gene family expansions previously reported in Octopus bimaculoides (e.g., zinc finger and cadherins, both associated with neural functions), as well as formation of novel gene families, dominate the genomic landscape in all octopods. Examination of tissue-specific genes in the posterior salivary gland revealed that expression was dominated by serine proteases in non-tetrodotoxin-bearing octopods, while this family was a minor component in H. maculosa. Moreover, voltage-gated sodium channels in H. maculosa contain a resistance mutation found in pufferfish and garter snakes, which is exclusive to the genus. Analysis of the posterior salivary gland microbiome revealed a diverse array of bacterial species, including genera that can produce tetrodotoxin, suggestive of a possible production source. CONCLUSIONS We present the first tetrodotoxin-bearing octopod genome H. maculosa, which displays lineage-specific adaptations to tetrodotoxin acquisition. This genome, along with other recently published cephalopod genomes, represents a valuable resource from which future work could advance our understanding of the evolution of genomic novelty in this family.
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Affiliation(s)
- Brooke L Whitelaw
- Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, 1 James Cook Dr, Douglas QLD 4811 , Australia
- Sciences, Museum Victoria, 11 Nicholson St, Carlton, Victoria 3053, Australia
| | - Ira R Cooke
- College of Public Health, Medical and Vet Sciences, James Cook University,1 James Cook Dr, Douglas QLD 4811 , Australia
- La Trobe Institute of Molecular Science, La Trobe University, Plenty Rd &, Kingsbury Dr, Bundoora, Melbourne, Victoria 3086, Australia
| | - Julian Finn
- Sciences, Museum Victoria, 11 Nicholson St, Carlton, Victoria 3053, Australia
| | - Rute R da Fonseca
- Center for Macroecology, Evolution and Climate (CMEC), GLOBE Institute, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen, Denmark
| | - Elena A Ritschard
- Department of Neurosciences and Developmental Biology, University of Vienna,Universitätsring 1, 1010 Wien, Vienna, Austria
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Naples, Italy
| | - M T P Gilbert
- Center for Evolutionary Hologenomics, GLOBE Institute, University of Copenhagen, Øster Voldgade 5–7, 1350 Copenhagen, Denmark
| | - Oleg Simakov
- Department of Neurosciences and Developmental Biology, University of Vienna,Universitätsring 1, 1010 Wien, Vienna, Austria
| | - Jan M Strugnell
- Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, 1 James Cook Dr, Douglas QLD 4811 , Australia
- Department of Ecology, Environment and Evolution, La Trobe University, Plenty Rd &, Kingsbury Dr, Bundoora, Melbourne, Victoria 3086, Australia
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11
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Convergent and parallel evolution in a voltage-gated sodium channel underlies TTX-resistance in the Greater Blue-ringed Octopus: Hapalochlaena lunulata. Toxicon 2019; 170:77-84. [DOI: 10.1016/j.toxicon.2019.09.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 09/09/2019] [Accepted: 09/11/2019] [Indexed: 12/24/2022]
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12
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Guardone L, Maneschi A, Meucci V, Gasperetti L, Nucera D, Armani A. A Global Retrospective Study on Human Cases of Tetrodotoxin (TTX) Poisoning after Seafood Consumption. FOOD REVIEWS INTERNATIONAL 2019. [DOI: 10.1080/87559129.2019.1669162] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Lisa Guardone
- FishLab, Department of Veterinary Sciences, University of Pisa, Pisa, Italy
| | - Andrea Maneschi
- FishLab, Department of Veterinary Sciences, University of Pisa, Pisa, Italy
| | - Valentina Meucci
- FishLab, Department of Veterinary Sciences, University of Pisa, Pisa, Italy
| | - Laura Gasperetti
- Istituto Zooprofilattico Sperimentale Lazio e Toscana, Pisa, Italy
| | - Daniele Nucera
- Department of Agriculture, Forest and Food Science, University of Turin, Turin, Italy
| | - Andrea Armani
- FishLab, Department of Veterinary Sciences, University of Pisa, Pisa, Italy
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Novel Polyclonal Antibody Raised against Tetrodotoxin Using Its Haptenic Antigen Prepared from 4,9-anhydrotetrodotoxin Reacted with 1,2-Ethaneditiol and Further Reacted with Keyhole Limpet Hemocyanin. Toxins (Basel) 2019; 11:toxins11100551. [PMID: 31547067 PMCID: PMC6832204 DOI: 10.3390/toxins11100551] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 12/04/2022] Open
Abstract
A novel polyclonal antibody against tetrodotoxin (TTX) was raised using its haptenic antigen, where 4,9-anhydroTTX was reacted with 1,2-ethanedithiol and this derivative was further reacted with keyhole limpet hemocyanin (KLH). This newly designed antigen (KLH-TTX) was inoculated into rabbits, resulting in the production of the specific polyclonal antibody, which reacted well with TTX and its analogs, 4-epiTTX, 11-oxoTTX and 5,6,11-trideoxyTTX, except for 4,9-anhydroTTX. The enzyme-linked immunosorbent assay (ELISA) system using this specific antibody was also developed in the present study. This newly developed polyclonal antibody with analytical procedures using direct one-step ELISA is useful to detect TTX and its analogs in toxic organisms and also disclose the mechanisms involved in their metabolic pathways and accumulation of TTX.
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Asakawa M, Matsumoto T, Umezaki K, Kaneko K, Yu X, Gomez-Delan G, Tomano S, Noguchi T, Ohtsuka S. Toxicity and Toxin Composition of the Greater Blue-Ringed Octopus Hapalochlaena lunulata from Ishigaki Island, Okinawa Prefecture, Japan. Toxins (Basel) 2019; 11:toxins11050245. [PMID: 31035711 PMCID: PMC6563023 DOI: 10.3390/toxins11050245] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 04/26/2019] [Accepted: 04/27/2019] [Indexed: 11/16/2022] Open
Abstract
The toxicity of the greater blue-ringed octopus Hapalochlaena lunulata, whose bite is fatal to humans, was examined to better understand and prevent deaths from accidental bites. Living specimens were collected from tide pools on Ishigaki Island, Okinawa Prefecture, Japan, in November and December of 2015, 2016, and 2017. The specimens were examined for the anatomical distribution of the toxicity, which was expressed in terms of mouse units (MU), by the standard bioassay method for tetrodotoxin (TTX) in Japan. Paralytic toxicity to mice was detected in all of the soft parts. The posterior salivary glands exhibited the highest toxicity score with a maximum level of 9276 MU/g, which was classified as "strongly toxic" (more than 1000 MU/g tissue) according to the classification of toxicity established by the Ministry of Health, Labor and Welfare of Japan, followed by the hepatopancreas (21.1 to 734.3 MU/g), gonads (not detectable to 167.6 MU/g), arms (5.3 to 130.2 MU/g), and other body areas (17.3 to 107.4 MU/g). Next, the toxin from the salivary glands was partially purified by a Sep-Pak C18 cartridge and an Amicon Ultra Centrifugal Filter with a 3000-Da cut-off, and analyzed by liquid chromatography-mass spectrometry (LC-MS) equipped with a φ2.0 × 150-mm (5 μm) TSKgel Amide-80 column (Tosoh, Tokyo, Japan) with a mixture of 16 mM ammonium formate buffer (pH 5.5) and acetonitrile (ratio 3:7, v/v) as a mobile phase. This study aimed to clarify the toxicity and the composition of TTX and its derivatives in this toxic octopus. The main toxin in this toxic octopus was identified as TTX, along with 4-epi TTX, 4, 9-anhydroTTX and 6-epi TTX. Further, the toxicity of this species is also significant from a food hygiene point of view.
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Affiliation(s)
- Manabu Asakawa
- Laboratory of Marine Bioresource Chemistry, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan.
| | - Takuya Matsumoto
- Faculty of Human Culture and Science, Prefectural University of Hiroshima, Hiroshima 734-8558, Japan.
| | - Kohei Umezaki
- Laboratory of Marine Bioresource Chemistry, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan.
| | - Kyoichiro Kaneko
- Laboratory of Marine Bioresource Chemistry, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan.
| | - Ximiao Yu
- Laboratory of Marine Bioresource Chemistry, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan.
| | - Gloria Gomez-Delan
- Department of Fisheries, Cebu Technological University-Carmen Campus, 6005 Cebu, Philippines.
| | - Satoshi Tomano
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles 90095, CA, USA.
| | - Tamao Noguchi
- Faculty of Healthcare, Tokyo Health Care University, Tokyo 154-8568, Japan.
| | - Susumu Ohtsuka
- Takehara Station, Setouchi Field Science Center, Graduate School of Biosphere Science, Hiroshima University, Takehara City, Hiroshima 725-0024, Japan.
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15
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Whitelaw BL, Cooke IR, Finn J, Zenger K, Strugnell JM. The evolution and origin of tetrodotoxin acquisition in the blue-ringed octopus (genus Hapalochlaena). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2019; 206:114-122. [PMID: 30472480 DOI: 10.1016/j.aquatox.2018.10.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 10/22/2018] [Accepted: 10/22/2018] [Indexed: 06/09/2023]
Abstract
Tetrodotoxin is a potent non-proteinaceous neurotoxin, which is commonly found in the marine environment. Synthesised by bacteria, tetrodotoxin has been isolated from the tissues of several genera including pufferfish, salamanders and octopus. Believed to provide a defensive function, the independent evolution of tetrodotoxin sequestration is poorly understood in most species. Two mechanisms of tetrodotoxin resistance have been identified to date, tetrodotoxin binding proteins in the circulatory system and mutations to voltage gated sodium channels, the binding target of tetrodotoxin with the former potentially succeeding the latter in evolutionary time. This review focuses on the evolution of tetrodotoxin acquisition, in particular how it may have occurred within the blue-ringed octopus genus (Hapalochlaena) and the subsequent impact on venom evolution.
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Affiliation(s)
- Brooke L Whitelaw
- Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville, Queensland, 4811, Australia.
| | - Ira R Cooke
- College of Public Health, Medical and Vet Sciences, James Cook University, Townsville, Queensland, 4811, Australia; La Trobe Institute of Molecular Science, La Trobe University, Melbourne, 3086, Vic. Australia
| | - Julian Finn
- Sciences, Museum Victoria, Carlton, Victoria 3053, Australia
| | - Kyall Zenger
- Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville, Queensland, 4811, Australia
| | - J M Strugnell
- Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville, Queensland, 4811, Australia; Department of Ecology, Environment and Evolution, La Trobe University, Melbourne, 3086, Vic. Australia
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16
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Kim HS, Kwun HJ, Bae H, Park J. First reliable record of the blue-lined octopus, Hapalochlaena fasciata (Hoyle, 1886) (Cephalopoda: Octopodidae), from Jeju Island, Korea. JOURNAL OF ASIA-PACIFIC BIODIVERSITY 2018. [DOI: 10.1016/j.japb.2018.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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17
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Tetrodotoxin-Producing Bacteria: Detection, Distribution and Migration of the Toxin in Aquatic Systems. Toxins (Basel) 2017; 9:toxins9050166. [PMID: 28513564 PMCID: PMC5450714 DOI: 10.3390/toxins9050166] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 05/12/2017] [Accepted: 05/12/2017] [Indexed: 01/18/2023] Open
Abstract
This review is devoted to the marine bacterial producers of tetrodotoxin (TTX), a potent non-protein neuroparalytic toxin. In addition to the issues of the ecology and distribution of TTX-producing bacteria, this review examines issues relating to toxin migration from bacteria to TTX-bearing animals. It is shown that the mechanism of TTX extraction from toxin-producing bacteria to the environment occur through cell death, passive/active toxin excretion, or spore germination of spore-forming bacteria. Data on TTX microdistribution in toxic organs of TTX-bearing animals indicate toxin migration from the digestive system to target organs through the transport system of the organism. The role of symbiotic microflora in animal toxicity is also discussed: despite low toxin production by bacterial strains in laboratory conditions, even minimal amounts of TTX produced by intestinal microflora of an animal can contribute to its toxicity. Special attention is paid to methods of TTX detection applicable to bacteria. Due to the complexity of toxin detection in TTX-producing bacteria, it is necessary to use several methods based on different methodological approaches. Issues crucial for further progress in detecting natural sources of TTX investigation are also considered.
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18
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Whitelaw BL, Strugnell JM, Faou P, da Fonseca RR, Hall NE, Norman M, Finn J, Cooke IR. Combined Transcriptomic and Proteomic Analysis of the Posterior Salivary Gland from the Southern Blue-Ringed Octopus and the Southern Sand Octopus. J Proteome Res 2016; 15:3284-97. [PMID: 27427999 DOI: 10.1021/acs.jproteome.6b00452] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This study provides comprehensive proteomic profiles from the venom producing posterior salivary glands of octopus (superorder Octopodiformes) species. A combined transcriptomic and proteomic approach was used to identify 1703 proteins from the posterior salivary gland of the southern blue-ringed octopus, Hapalochlaena maculosa and 1300 proteins from the posterior salivary gland of the southern sand octopus, Octopus kaurna. The two proteomes were broadly similar; clustering of proteins into orthogroups revealed 937 that were shared between species. Serine proteases were particularly diverse and abundant in both species. Other abundant proteins included a large number of secreted proteins, many of which had no known conserved domains, or homology to proteins with known function. On the basis of homology to known venom proteins, 23 putative toxins were identified in H. maculosa and 24 in O. kaurna. These toxins span nine protein families: CAP (cysteine rich secretory proteins, antigen 5, parthenogenesis related), chitinase, carboxylesterase, DNase, hyaluronidase, metalloprotease, phospholipase, serine protease and tachykinin. Serine proteases were responsible for 70.9% and 86.3% of putative toxin expression in H. maculosa and O. kaurna, respectively, as determined using intensity based absolute quantification (iBAQ) measurements. Phylogenetic analysis of the putative toxin serine proteases revealed a similar suite of diverse proteins present in both species. Posterior salivary gland composition of H. maculosa and O. kaurna differ in several key aspects. While O. kaurna expressed the proteinaceous neurotoxin, tachykinin, this was absent from H. maculosa, perhaps reflecting the acquisition of a potent nonproteinaceous neurotoxin, tetrodotoxin (TTX) produced by bacteria in the salivary glands of that species. The dispersal factor, hyaluronidase was particularly abundant in H. maculosa. Chitinase was abundant in both species and is believed to facilitate envenomation in chitinous prey such as crustaceans. Cephalopods represent a largely unexplored source of novel proteins distinct from all other venomous taxa and are of interest for further inquiry, as novel proteinaceous toxins derived from venoms may contribute to pharmaceutical design.
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Affiliation(s)
- Brooke L Whitelaw
- Department of Ecology, Environment and Evolution, School of Life Sciences, La Trobe University , Melbourne, Victoria 3086, Australia.,Life Sciences Computation Centre, Victorian Life Sciences Computation Initiative , Carlton, Victoria 3053, Australia
| | - Jan M Strugnell
- Department of Ecology, Environment and Evolution, School of Life Sciences, La Trobe University , Melbourne, Victoria 3086, Australia
| | - Pierre Faou
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University , Melbourne, Victoria 3086, Australia
| | - Rute R da Fonseca
- The Bioinformatics Centre, Department of Biology, University of Copenhagen , Ole Maaløes Vej 5, 2200 København N, Denmark
| | - Nathan E Hall
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University , Melbourne, Victoria 3086, Australia.,Sciences, Museum Victoria , Carlton, Victoria 3053, Australia
| | - Mark Norman
- Sciences, Museum Victoria , Carlton, Victoria 3053, Australia
| | - Julian Finn
- Sciences, Museum Victoria , Carlton, Victoria 3053, Australia
| | - Ira R Cooke
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University , Melbourne, Victoria 3086, Australia.,Comparative Genomics Centre and Department of Molecular and Cell Biology, James Cook University , Townsville, Queensland 4811, Australia
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Magarlamov TY, Shokur OA, Chernyshev AV. Distribution of tetrodotoxin in the ribbon worm Lineus alborostratus (Takakura, 1898) (nemertea): Immunoelectron and immunofluorescence studies. Toxicon 2016; 112:29-34. [PMID: 26821373 DOI: 10.1016/j.toxicon.2016.01.060] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 01/13/2016] [Accepted: 01/20/2016] [Indexed: 11/16/2022]
Abstract
Transmission electron and confocal laser scanning (CLSM) microscopies with monoclonal anti-tetrodotoxin antibodies were used to locate tetrodotoxin (TTX) in tissues and gland cells of the ribbon worm Lineus alborostratus. CLSM studies have shown that the toxin is primarily localized in the cutis (special subepidermal layer) of the body wall and in the glandular epithelium of the proboscis. Immunoelectron micrographs have shown that only subepidermal bacillary gland cells type I in cutis and pseudocnidae-containing and mucoid gland cells manifested TTX-gold labeling. TTX was associated with the nuclear envelope, endoplasmic reticulum membrane, and secretory granules of TTX-positive gland cells. These studies indicate that ТТХ is brought into the cytoplasm of the glandular cells of the cutis and proboscis epithelium, where it is associated with membrane-enclosed organelles involved in protein secretion and then concentrated in glandular granules.
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Affiliation(s)
- Timur Yu Magarlamov
- A.V. Zhirmunsky Institute of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia; School of Biomedicine, Far Eastern Federal University, Vladivostok, Russia.
| | - Olga A Shokur
- School of Biomedicine, Far Eastern Federal University, Vladivostok, Russia
| | - Alexey V Chernyshev
- A.V. Zhirmunsky Institute of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia; School of Natural Sciences, Far Eastern Federal University, Vladivostok, Russia
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20
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Wu YJ, Lin CL, Chen CH, Hsieh CH, Jen HC, Jian SJ, Hwang DF. Toxin and species identification of toxic octopus implicated into food poisoning in Taiwan. Toxicon 2014; 91:96-102. [PMID: 25286395 DOI: 10.1016/j.toxicon.2014.09.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 08/22/2014] [Accepted: 09/24/2014] [Indexed: 10/24/2022]
Abstract
A food poisoning incident due to ingestion of unknown octopus occurred in Taipei in December, 2010. The serum and urine from victims (male 38 and 43 years old) were collected, determined the toxicity, and identified tetrodotoxin (TTX) by high-performance liquid chromatography with tandem mass spectrometry (LC-MS/MS). It was found that only urine contained the trace of TTX. Then, two retained specimen (one without blue ring in the skin and another with small blue ring in the skin) were collected from victims and examined for the toxicity and toxin. Meanwhile, 6 specimens of octopus without blue ring in the skin and 4 specimens of octopus with blue ring in the skin were re-collected from the market. Both retained octopus samples were found to contain TTX. However, re-collected market's octopus without blue ring in the skin did not show to contain TTX the and was identified as Octopus aegina by using the analysis of cytochrome b gene (Cyt b) and cytochrome c oxidase subunit I gene (COI). Only octopus with blue ring in the skin contained TTX and was identified as Hapalochlaena fasciata by using the analysis of Cyt b and COI. Therefore, this octopus food poisoning was caused by toxic octopus H. fasciata and the causative agent was TTX.
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Affiliation(s)
- Ya-Jung Wu
- Department of Food Technology and Marketing Management, Taipei College of Maritime Technology, Taipei, Taiwan
| | - Chun-Lan Lin
- Department of Food Science and Center of Excellence for Marine Science, National Taiwan Ocean University, Taiwan
| | - Chien-Hung Chen
- Department of Food Science and Center of Excellence for Marine Science, National Taiwan Ocean University, Taiwan
| | - Cheng-Hong Hsieh
- Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan
| | - Hsiao-Chin Jen
- Department of Food Technology and Marketing Management, Taipei College of Maritime Technology, Taipei, Taiwan
| | - Shi-Jie Jian
- Division of Nephrology, Department of Internal Medicine, Mackay Memorial Hospital, Taipei, Taiwan
| | - Deng-Fwu Hwang
- Department of Food Science and Center of Excellence for Marine Science, National Taiwan Ocean University, Taiwan; Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan.
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21
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Cornet V, Henry J, Corre E, Le Corguille G, Zanuttini B, Zatylny-Gaudin C. Dual role of the cuttlefish salivary proteome in defense and predation. J Proteomics 2014; 108:209-22. [PMID: 24892799 DOI: 10.1016/j.jprot.2014.05.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Revised: 05/23/2014] [Accepted: 05/25/2014] [Indexed: 10/25/2022]
Abstract
UNLABELLED We characterized the proteome of the posterior salivary glands of the cephalopod S. officinalis by combining de novo RNA sequencing and mass spectrometry. In silico analysis of the transcriptome revealed the occurrence of three main categories of proteins: enzymes, immune factors and toxins. Protein identification by SDS-PAGE and MALDI-TOF/TOF confirmed the occurrence of proteins essential to venom-like enzymes: peptidase S1 under four isoforms, phospholipase A2 and two toxins. The first toxin is a cystein rich secreted protein (CRISP), a common toxin found in all venomous animals. The second one is cephalotoxin, which is specific to decabrachia cephalopods. Secretions of the posterior salivary glands are transported to the cephalopodium; they are involved in prey catching but also in gamete storage, fertilization and egg-laying. The paralyzing activity and the antimicrobial effect of saliva suggest a dual role in predation and in immune defense in cuttlefish. BIOLOGICAL SIGNIFICANCE The originality of this study lies in the use of a transcriptomic approach (de novo RNA sequencing) coupled to a proteomic approach to get an overview of posterior salivary glands in S. officinalis. In cephalopods, these glands are involved in predation, more precisely in paralyzing preys and digesting them. Our in silico analysis equally reveals a role in immune defense as observed in mammals' saliva. Our study also shows the specificity of cuttlefish venom, with the identification of cephalotoxins, proteins that are not found in octopuses. Finally, we show that cuttlefish saliva is a complex mixture that has antibacterial and crippling properties, but no lethal effect.
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Affiliation(s)
- Valérie Cornet
- Université de Caen Basse-Normandie, IBFA, F-14032 Caen, France; UMR BOREA, MNHN, UPMC, CNRS-7208, IRD-207, UCBN, F-14032 Caen, France
| | - Joël Henry
- Université de Caen Basse-Normandie, IBFA, F-14032 Caen, France; UMR BOREA, MNHN, UPMC, CNRS-7208, IRD-207, UCBN, F-14032 Caen, France; Post Genomic Platform PROTEOGEN, Université de Caen Basse-Normandie, F-14032 Caen, France
| | - Erwan Corre
- ABiMs Platform, Station biologique de Roscoff (UPMC-CNRS), F-29688 Roscoff, France
| | - Gildas Le Corguille
- ABiMs Platform, Station biologique de Roscoff (UPMC-CNRS), F-29688 Roscoff, France
| | - Bruno Zanuttini
- Université de Caen Basse-Normandie, GREYC, UMR 6072, UNICAEN, CNRS, ENSICAEN, F-14032 Caen, France
| | - Céline Zatylny-Gaudin
- Université de Caen Basse-Normandie, IBFA, F-14032 Caen, France; UMR BOREA, MNHN, UPMC, CNRS-7208, IRD-207, UCBN, F-14032 Caen, France.
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22
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Derby CD. Cephalopod ink: production, chemistry, functions and applications. Mar Drugs 2014; 12:2700-30. [PMID: 24824020 PMCID: PMC4052311 DOI: 10.3390/md12052700] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 04/10/2014] [Accepted: 04/14/2014] [Indexed: 01/17/2023] Open
Abstract
One of the most distinctive and defining features of coleoid cephalopods—squid, cuttlefish and octopus—is their inking behavior. Their ink, which is blackened by melanin, but also contains other constituents, has been used by humans in various ways for millennia. This review summarizes our current knowledge of cephalopod ink. Topics include: (1) the production of ink, including the functional organization of the ink sac and funnel organ that produce it; (2) the chemical components of ink, with a focus on the best known of these—melanin and the biochemical pathways involved in its production; (3) the neuroecology of the use of ink in predator-prey interactions by cephalopods in their natural environment; and (4) the use of cephalopod ink by humans, including in the development of drugs for biomedical applications and other chemicals for industrial and other commercial applications. As is hopefully evident from this review, much is known about cephalopod ink and inking, yet more striking is how little we know. Towards closing that gap, future directions in research on cephalopod inking are suggested.
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Affiliation(s)
- Charles D Derby
- Neuroscience Institute and Department of Biology, Georgia State University, P.O. Box 5030, Atlanta, GA 30302-5030, USA.
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Bane V, Lehane M, Dikshit M, O'Riordan A, Furey A. Tetrodotoxin: chemistry, toxicity, source, distribution and detection. Toxins (Basel) 2014; 6:693-755. [PMID: 24566728 PMCID: PMC3942760 DOI: 10.3390/toxins6020693] [Citation(s) in RCA: 202] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 01/24/2014] [Accepted: 01/26/2014] [Indexed: 11/16/2022] Open
Abstract
Tetrodotoxin (TTX) is a naturally occurring toxin that has been responsible for human intoxications and fatalities. Its usual route of toxicity is via the ingestion of contaminated puffer fish which are a culinary delicacy, especially in Japan. TTX was believed to be confined to regions of South East Asia, but recent studies have demonstrated that the toxin has spread to regions in the Pacific and the Mediterranean. There is no known antidote to TTX which is a powerful sodium channel inhibitor. This review aims to collect pertinent information available to date on TTX and its analogues with a special emphasis on the structure, aetiology, distribution, effects and the analytical methods employed for its detection.
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Affiliation(s)
- Vaishali Bane
- Mass Spectrometry Research Centre (MSRC) and PROTEOBIO Research Groups, Department of Chemistry, Cork Institute of Technology, Rossa Avenue, Bishopstown, Cork, Ireland.
| | - Mary Lehane
- Mass Spectrometry Research Centre (MSRC) and PROTEOBIO Research Groups, Department of Chemistry, Cork Institute of Technology, Rossa Avenue, Bishopstown, Cork, Ireland.
| | | | - Alan O'Riordan
- Nanotechnology Group, Tyndall National Institute, University College Cork, Lee Maltings, Cork, Ireland.
| | - Ambrose Furey
- Mass Spectrometry Research Centre (MSRC) and PROTEOBIO Research Groups, Department of Chemistry, Cork Institute of Technology, Rossa Avenue, Bishopstown, Cork, Ireland.
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Khor S, Wood SA, Salvitti L, Taylor DI, Adamson J, McNabb P, Cary SC. Investigating diet as the source of tetrodotoxin in Pleurobranchaea maculata. Mar Drugs 2013; 12:1-16. [PMID: 24368566 PMCID: PMC3917257 DOI: 10.3390/md12010001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 11/18/2013] [Accepted: 12/02/2013] [Indexed: 11/18/2022] Open
Abstract
The origin of tetrodotoxin (TTX) is highly debated; researchers have postulated either an endogenous or exogenous source with the host accumulating TTX symbiotically or via food chain transmission. The aim of this study was to determine whether the grey side-gilled sea slug (Pleurobranchaea maculata) could obtain TTX from a dietary source, and to attempt to identify this source through environmental surveys. Eighteen non-toxic P. maculata were maintained in aquariums and twelve were fed a TTX-containing diet. Three P. maculata were harvested after 1 h, 24 h, 17 days and 39 days and TTX concentrations in their stomach, gonad, mantle and remaining tissue/fluids determined using liquid chromatography-mass spectrometry. Tetrodotoxin was detected in all organs/tissue after 1 h with an average uptake of 32%. This decreased throughout the experiment (21%, 15% and 9%, respectively). Benthic surveys at sites with dense populations of toxic P. maculata detected very low or no TTX in other organisms. This study demonstrates that P. maculata can accumulate TTX through their diet. However, based on the absence of an identifiable TTX source in the environment, in concert with the extremely high TTX concentrations and short life spans of P. maculata, it is unlikely to be the sole TTX source for this species.
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Affiliation(s)
- Serena Khor
- Department of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand; E-Mails: (S.K.); (L.S.); (S.C.C.)
| | - Susanna A. Wood
- Department of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand; E-Mails: (S.K.); (L.S.); (S.C.C.)
- Cawthron Institute, Nelson 7042, New Zealand; E-Mails: (D.I.T.); (J.A.); (P.M.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +64-3-548-2319; Fax: +64-3-546-9464
| | - Lauren Salvitti
- Department of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand; E-Mails: (S.K.); (L.S.); (S.C.C.)
| | - David I. Taylor
- Cawthron Institute, Nelson 7042, New Zealand; E-Mails: (D.I.T.); (J.A.); (P.M.)
| | - Janet Adamson
- Cawthron Institute, Nelson 7042, New Zealand; E-Mails: (D.I.T.); (J.A.); (P.M.)
| | - Paul McNabb
- Cawthron Institute, Nelson 7042, New Zealand; E-Mails: (D.I.T.); (J.A.); (P.M.)
- Department of Chemistry, Otago University, Dunedin 9054, New Zealand
| | - Stephen Craig Cary
- Department of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand; E-Mails: (S.K.); (L.S.); (S.C.C.)
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Asakawa M, Ito K, Kajihara H. Highly toxic ribbon worm Cephalothrix simula containing tetrodotoxin in Hiroshima Bay, Hiroshima Prefecture, Japan. Toxins (Basel) 2013; 5:376-95. [PMID: 23430577 PMCID: PMC3640541 DOI: 10.3390/toxins5020376] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 01/30/2013] [Accepted: 02/07/2013] [Indexed: 11/16/2022] Open
Abstract
In 1998, during a toxicological surveillance of various marine fouling organisms in Hiroshima Bay, Japan, specimens of the ribbon worm, Cephalothrix simula (Nemertea: Palaeonemertea) were found. These ribbon worms contained toxins with extremely strong paralytic activity. The maximum toxicity in terms of tetrodotoxin (TTX) was 25,590 mouse units (MU) per gram for the whole worm throughout the monitoring period. The main toxic component was isolated and recrystallized from an acidified methanolic solution. The crystalline with a specific toxicity of 3520 MU/mg was obtained and identified as TTX by high performance liquid chromatography (HPLC)-fluorescent detection (FLD) (HPLC-FLD), electrospray ionization-mass spectrometry (ESI-MS), infrared (IR), nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS). The highest toxicity of C. simula exceeded the human lethal dose per a single worm. A toxicological surveillance of C. simula from 1998 to 2005 indicated approximately 80% of the individuals were ranked as "strongly toxic" (≥1000 MU/g). Forty-eight percent of the specimens possessed toxicity scores of more than 2000 MU/g. Seasonal variations were observed in the lethal potency of C. simula. Specimens collected on January 13, 2000 to December 26, 2000 showed mean toxicities of 665-5300 MU/g (n = 10). These data prompted a toxicological surveillance of ribbon worms from other localities with different habitats in Japan, including Akkeshi Bay (Hokkaido) under stones on rocky intertidal beaches, as well as Otsuchi (Iwate) among calcareous tubes of serpulid polychaetes on rocky shores. Within twelve species of ribbon worms examined, only C. simula possessed extremely high toxicity. Therefore, C. simula appears to show generally high toxicity irrespective of their locality and habitat.
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Affiliation(s)
- Manabu Asakawa
- Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8528, Japan
| | - Katsutoshi Ito
- National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, Maruishi 2-17-5, Hatsukaichi, Hiroshima 739-0452, Japan; E-Mail:
| | - Hiroshi Kajihara
- Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan; E-Mail:
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Microdistribution of tetrodotoxin in two species of blue-ringed octopuses (Hapalochlaena lunulata and Hapalochlaena fasciata) detected by fluorescent immunolabeling. Toxicon 2012; 60:1307-13. [DOI: 10.1016/j.toxicon.2012.08.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2012] [Revised: 08/21/2012] [Accepted: 08/29/2012] [Indexed: 11/24/2022]
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Depuration of tetrodotoxin and changes in bacterial communities in Pleurobranchea maculata adults and egg masses maintained in captivity. J Chem Ecol 2012; 38:1342-50. [PMID: 23151964 DOI: 10.1007/s10886-012-0212-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 09/17/2012] [Accepted: 10/22/2012] [Indexed: 10/27/2022]
Abstract
Depuration of tetrodotoxin (TTX) was investigated in adult grey side-gilled sea slugs, Pleurobranchaea maculata, maintained in captivity on a TTX-free diet. Three adults were harvested every 21 days for 126 days, and TTX concentrations were measured in organs/tissues and egg masses. Automated rRNA intergenic spacer analysis (ARISA) was used to investigate bacterial community structure in selected samples. Linear modeling of adult data demonstrated a decline (P<0.001) in average total TTX concentrations over time. Temporal data obtained from a wild population showed similar depuration rates, indicating that once adults reach a certain size, or sexual maturity, TTX is no longer produced or acquired substantially. Depuration rates differed among organs, with concentrations in the heart declining the fastest. The gonads had the slowest and least significant depuration rate indicating, at most, weak depuration of this tissue. There was a strong correlation (R(2)=0.66) between TTX concentrations in the first-laid egg masses and total TTX in the corresponding adult. These data suggest that adult P. maculata transfer TTX to their offspring, and presumably that functions as a chemical defense. ARISA data showed a shift in bacterial community structure within 3 weeks of introduction to captivity. Based on the combined data, the exact origin of TTX in P. maculata is unclear, with evidence both in favor and against a dietary source, and endogenous or bacterial production.
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Adaptive evolution of voltage-gated sodium channels: the first 800 million years. Proc Natl Acad Sci U S A 2012; 109 Suppl 1:10619-25. [PMID: 22723361 DOI: 10.1073/pnas.1201884109] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Voltage-gated Na(+)-permeable (Nav) channels form the basis for electrical excitability in animals. Nav channels evolved from Ca(2+) channels and were present in the common ancestor of choanoflagellates and animals, although this channel was likely permeable to both Na(+) and Ca(2+). Thus, like many other neuronal channels and receptors, Nav channels predated neurons. Invertebrates possess two Nav channels (Nav1 and Nav2), whereas vertebrate Nav channels are of the Nav1 family. Approximately 500 Mya in early chordates Nav channels evolved a motif that allowed them to cluster at axon initial segments, 50 million years later with the evolution of myelin, Nav channels "capitalized" on this property and clustered at nodes of Ranvier. The enhancement of conduction velocity along with the evolution of jaws likely made early gnathostomes fierce predators and the dominant vertebrates in the ocean. Later in vertebrate evolution, the Nav channel gene family expanded in parallel in tetrapods and teleosts (∼9 to 10 genes in amniotes, 8 in teleosts). This expansion occurred during or after the late Devonian extinction, when teleosts and tetrapods each diversified in their respective habitats, and coincided with an increase in the number of telencephalic nuclei in both groups. The expansion of Nav channels may have allowed for more sophisticated neural computation and tailoring of Nav channel kinetics with potassium channel kinetics to enhance energy savings. Nav channels show adaptive sequence evolution for increasing diversity in communication signals (electric fish), in protection against lethal Nav channel toxins (snakes, newts, pufferfish, insects), and in specialized habitats (naked mole rats).
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Townsend KA, Altvater J, Thomas MC, Schuyler QA, Nette GW. Death in the octopus' garden: fatal blue-lined octopus envenomations of adult green sea turtles. MARINE BIOLOGY 2011; 159:689-695. [PMID: 24391271 PMCID: PMC3873062 DOI: 10.1007/s00227-011-1846-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 11/18/2011] [Indexed: 05/12/2023]
Abstract
The blue-lined octopus Hapalochlaena fasciata contains the powerful neuromuscular blocker tetrodotoxin (TTX), which causes muscle weakness and respiratory failure. H. fasciata is regarded as one of the most venomous marine animals in the world, and multiple human fatalities have been attributed to the octopus. To date, there have been no recorded incidents of an envenomation of a wild animal. Here, we present a newly developed, multi-stage tandem mass spectrometry technique that provides unequivocal evidence for two cases of envenomation of two ~110 kg herbivorous green sea turtles by two tiny cryptic blue-lined octopuses (~4 cm body length). These cases of accidental ingestion provide evidence for the first time of the antipredator effect of TTX and highlight a previously unconsidered threat to turtles grazing within seagrass beds.
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Affiliation(s)
- Kathy A. Townsend
- School of Biological Sciences, The University of Queensland, Moreton Bay Research Station, P.O. Box 138, Dunwich, QLD 4183 Australia
| | - Jens Altvater
- Independent Marine Biochemistry Research, Moreton Bay Research Station, P.O. Box 138, Dunwich, QLD 4183 Australia
| | - Michael C. Thomas
- Independent Marine Biochemistry Research, Moreton Bay Research Station, P.O. Box 138, Dunwich, QLD 4183 Australia
| | - Qamar A. Schuyler
- School of Biological Sciences, The University of Queensland, Moreton Bay Research Station, P.O. Box 138, Dunwich, QLD 4183 Australia
| | - Geoffrey W. Nette
- Independent Marine Biochemistry Research, Moreton Bay Research Station, P.O. Box 138, Dunwich, QLD 4183 Australia
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Wu YJ, Cheng YJ, Jen HC, Pan CH, Lin TC, Lin SJ, Hwang DF. Liquid chromatography-tandem mass spectrometry determination of the toxicity and identification of fish species in a suspected tetrodotoxin fish poisoning. J Food Prot 2011; 74:789-95. [PMID: 21549050 DOI: 10.4315/0362-028x.jfp-10-435] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Suspected tetrodotoxin (TTX) poisoning was associated with eating unknown fish in April 2009 in Taiwan. After ingestion of the fish, symptoms of the victim included perioral paresthesia, nausea, vomiting, ataxia, weakness of all limbs, respiration failure, and death within several hours. The toxicity in the remaining fish was determined, with the mice exhibiting symptoms of neurotoxin poisoning. The implicated fish and deceased victim tissues were analyzed for TTX by liquid chromatography-tandem mass spectrometry. The urine, bile, cerebrospinal fluid (spinal cord), pleural effusion, and pericardial effusion of the victim contained TTX. In addition, the partial cytochrome b gene of the implicated fish was determined by PCR. The DNA sequence in the partial 465-bp cytochrome b gene identified the implicated fish as Chelonodon patoca (puffer fish). These results indicate that people should avoid eating unknown fish species from fish markets where harvested fish may include toxic species.
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Affiliation(s)
- Ya-Jung Wu
- Department of Food Science, National Taiwan Ocean University, Keelung, Taiwan
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Chemical defense in pelagic octopus paralarvae: Tetrodotoxin alone does not protect individual paralarvae of the greater blue-ringed octopus (Hapalochlaena lunulata) from common reef predators. CHEMOECOLOGY 2011. [DOI: 10.1007/s00049-011-0075-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Williams BL, Hanifin CT, Brodie ED, Caldwell RL. Ontogeny of Tetrodotoxin Levels in Blue-ringed Octopuses: Maternal Investment and Apparent Independent Production in Offspring of Hapalochlaena lunulata. J Chem Ecol 2010; 37:10-7. [DOI: 10.1007/s10886-010-9901-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 11/24/2010] [Accepted: 12/08/2010] [Indexed: 10/18/2022]
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Paul VJ, Ritson-Williams R, Sharp K. Marine chemical ecology in benthic environments. Nat Prod Rep 2010; 28:345-87. [PMID: 21125086 DOI: 10.1039/c0np00040j] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Valerie J Paul
- Smithsonian Marine Station, Smithsonian Institution, Fort Pierce, Florida, USA.
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Behavioral and chemical ecology of marine organisms with respect to tetrodotoxin. Mar Drugs 2010; 8:381-98. [PMID: 20411104 PMCID: PMC2857358 DOI: 10.3390/md8030381] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 02/24/2010] [Accepted: 02/25/2010] [Indexed: 11/26/2022] Open
Abstract
The behavioral and chemical ecology of marine organisms that possess tetrodotoxin (TTX) has not been comprehensively reviewed in one work to date. The evidence for TTX as an antipredator defense, as venom, as a sex pheromone, and as an attractant for TTX-sequestering organisms is discussed. Little is known about the adaptive value of TTX in microbial producers; thus, I focus on what is known about metazoans that are purported to accumulate TTX through diet or symbioses. Much of what has been proposed is inferred based on the anatomical distribution of TTX. Direct empirical tests of these hypotheses are absent in most cases.
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Williams BL, Caldwell RL. Intra-organismal distribution of tetrodotoxin in two species of blue-ringed octopuses (Hapalochlaena fasciata and H. lunulata). Toxicon 2009; 54:345-53. [DOI: 10.1016/j.toxicon.2009.05.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Revised: 05/01/2009] [Accepted: 05/11/2009] [Indexed: 10/20/2022]
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