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Suat Ozbek - One of the best experts on this subject based on the ideXlab platform.
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microbial arms race ballistic Nematocysts in dinoflagellates represent a new extreme in organelle complexity
Science Advances, 2017Co-Authors: Gregory S Gavelis, Kevin C Wakeman, Urban Tillmann, Christina Ripken, Satoshi Mitarai, Maria Herranz, Suat Ozbek, Thomas W Holstein, Patrick J. KeelingAbstract:We examine the origin of harpoon-like secretory organelles (Nematocysts) in dinoflagellate protists. These ballistic organelles have been hypothesized to be homologous to similarly complex structures in animals (cnidarians); but we show, using structural, functional, and phylogenomic data, that Nematocysts evolved independently in both lineages. We also recorded the first high-resolution videos of Nematocyst discharge in dinoflagellates. Unexpectedly, our data suggest that different types of dinoflagellate Nematocysts use two fundamentally different types of ballistic mechanisms: one type relies on a single pressurized capsule for propulsion, whereas the other type launches 11 to 15 projectiles from an arrangement similar to a Gatling gun. Despite their radical structural differences, these Nematocysts share a single origin within dinoflagellates and both potentially use a contraction-based mechanism to generate ballistic force. The diversity of traits in dinoflagellate Nematocysts demonstrates a stepwise route by which simple secretory structures diversified to yield elaborate subcellular weaponry.
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Minicollagen cysteine-rich domains encode distinct modes of polymerization to form stable Nematocyst capsules
Scientific Reports, 2016Co-Authors: Anja Tursch, Davide Mercadante, Jutta Tennigkeit, Frauke Gräter, Suat OzbekAbstract:The stinging capsules of cnidarians, Nematocysts, function as harpoon-like organelles with unusual biomechanical properties. The nanosecond discharge of the Nematocyst requires a dense protein network of the capsule structure withstanding an internal pressure of up to 150 bar. Main components of the capsule are short collagens, so-called minicollagens, that form extended polymers by disulfide reshuffling of their cysteine-rich domains (CRDs). Although CRDs have identical cysteine patterns, they exhibit different structures and disulfide connectivity at minicollagen N and C-termini. We show that the structurally divergent CRDs have different cross-linking potentials in vitro and in vivo . While the C-CRD can participate in several simultaneous intermolecular disulfides and functions as a cystine knot after minicollagen synthesis, the N-CRD is monovalent. Our combined experimental and computational analyses reveal the cysteines in the C-CRD fold to exhibit a higher structural propensity for disulfide bonding and a faster kinetics of polymerization. During Nematocyst maturation, the highly reactive C-CRD is instrumental in efficient cross-linking of minicollagens to form pressure resistant capsules. The higher ratio of C-CRD folding types evidenced in the medusozoan lineage might have fostered the evolution of novel, predatory Nematocyst types in cnidarians with a free-swimming medusa stage.
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the Nematocyst a molecular map of the cnidarian stinging organelle
The International Journal of Developmental Biology, 2012Co-Authors: Anna Beckmann, Suat OzbekAbstract:Nematocysts or cnidocysts represent the common feature of all cnidarians. They are large organelles produced from the Golgi apparatus as a secretory product within a specialized cell, the nematocyte or cnidocyte. Nematocysts are predominantly used for prey capture and defense, but also for locomotion. In spite of large variations in size and morphology, Nematocysts share a common build comprising a cylindrical capsule to which a long hollow thread is attached. The thread is inverted and coiled within the capsule and may be armed with spines in some Nematocyst types. During the discharge of Nematocysts following a chemical or mechanical stimulus, the thread is expelled from within the capsule matrix in a harpoon-like fashion. This process constitutes one of the fastest in biology and is accompanied by a release of toxins that are potentially harmful also for humans. The long history of research on Hydra as a model organism has been accompanied by the cellular, mechanistic and morphological analysis of its Nematocyst repertoire. Although representing one of the most complex organelles of the animal kingdom, the evolutionary origin and molecular map of the Nematocyst has remained largely unknown. Recent efforts in unraveling the molecular content of this fascinating organelle have revealed intriguing parallels to the extracellular matrix.
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The cnidarian Nematocyst: a miniature extracellular matrix within a secretory vesicle
Protoplasma, 2011Co-Authors: Suat OzbekAbstract:Nematocysts are the taxon-defining features of all cnidarians including jellyfish, sea anemones, and corals. They are highly sophisticated organelles used for the capture of prey and defense. The Nematocyst capsule is produced within a giant post-Golgi vesicle, which is continuously fed by proteins from the secretory pathway. Mature Nematocysts consist of a hollow capsule body in which a long tubule is coiled up that, upon discharge, is expelled in a harpoon-like fashion. This is accompanied by the release of a toxin cocktail stored in the capsule matrix. Nematocyst discharge, which is one of the fastest processes in biology, is driven by an extreme osmotic pressure of about 150 bar. The molecular analysis of the Nematocyst has from the beginning indicated a collagenous nature of the capsule structure. In particular, a large family of unusual minicollagens has been demonstrated to form the highly resistant scaffold of the capsule. Recent findings on the molecular composition of Hydra Nematocysts have confirmed the notion of a specialized extracellular matrix, which is assembled during an intracellular secretion process to form the most complex predatory apparatus at the cellular level.
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nematogalectin a Nematocyst protein with glyxy and galectin domains demonstrates nematocyte specific alternative splicing in hydra
Proceedings of the National Academy of Sciences of the United States of America, 2010Co-Authors: Jung Shan Hwang, Suat Ozbek, Patrizia Adamczyk, Yasuharu Takaku, Tsuyoshi Momose, Kazuho Ikeo, Konstantin Khalturin, Georg Hemmrich, Thomas C G Bosch, Thomas W HolsteinAbstract:Taxonomically restricted genes or lineage-specific genes contribute to morphological diversification in metazoans and provide unique functions for particular taxa in adapting to specific environments. To understand how such genes arise and participate in morphological evolution, we have investigated a gene called nematogalectin in Hydra, which has a structural role in the formation of Nematocysts, stinging organelles that are unique to the phylum Cnidaria. Nematogalectin is a 28-kDa protein with an N-terminal GlyXY domain (glycine followed by two hydrophobic amino acids), which can form a collagen triple helix, followed by a galactose-binding lectin domain. Alternative splicing of the nematogalectin transcript allows the gene to encode two proteins, nematogalectin A and nematogalectin B. We demonstrate that expression of nematogalectin A and B is mutually exclusive in different Nematocyst types: Desmonemes express nematogalectin B, whereas stenoteles and isorhizas express nematogalectin B early in differentiation, followed by nematogalectin A. Like Hydra, the marine hydrozoan Clytia also has two nematogalectin transcripts, which are expressed in different nematocyte types. By comparison, anthozoans have only one nematogalectin gene. Gene phylogeny indicates that tandem duplication of nematogalectin B exons gave rise to nematogalectin A before the divergence of Anthozoa and Medusozoa and that nematogalectin A was subsequently lost in Anthozoa. The emergence of nematogalectin A may have played a role in the morphological diversification of Nematocysts in the medusozoan lineage.
Thomas W Holstein - One of the best experts on this subject based on the ideXlab platform.
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microbial arms race ballistic Nematocysts in dinoflagellates represent a new extreme in organelle complexity
Science Advances, 2017Co-Authors: Gregory S Gavelis, Kevin C Wakeman, Urban Tillmann, Christina Ripken, Satoshi Mitarai, Maria Herranz, Suat Ozbek, Thomas W Holstein, Patrick J. KeelingAbstract:We examine the origin of harpoon-like secretory organelles (Nematocysts) in dinoflagellate protists. These ballistic organelles have been hypothesized to be homologous to similarly complex structures in animals (cnidarians); but we show, using structural, functional, and phylogenomic data, that Nematocysts evolved independently in both lineages. We also recorded the first high-resolution videos of Nematocyst discharge in dinoflagellates. Unexpectedly, our data suggest that different types of dinoflagellate Nematocysts use two fundamentally different types of ballistic mechanisms: one type relies on a single pressurized capsule for propulsion, whereas the other type launches 11 to 15 projectiles from an arrangement similar to a Gatling gun. Despite their radical structural differences, these Nematocysts share a single origin within dinoflagellates and both potentially use a contraction-based mechanism to generate ballistic force. The diversity of traits in dinoflagellate Nematocysts demonstrates a stepwise route by which simple secretory structures diversified to yield elaborate subcellular weaponry.
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a fast recoiling silk like elastomer facilitates nanosecond Nematocyst discharge
BMC Biology, 2015Co-Authors: Anna Beckmann, Thomas W Holstein, Senbo Xiao, Jochen P Muller, Davide Mercadante, Timm Nuchter, Niels Kroger, Florian Langhojer, Wolfgang Petrich, Martin BenoitAbstract:The discharge of the Cnidarian stinging organelle, the Nematocyst, is one of the fastest processes in biology and involves volume changes of the highly pressurised (150 bar) capsule of up to 50%. Hitherto, the molecular basis for the unusual biomechanical properties of Nematocysts has been elusive, as their structure was mainly defined as a stress-resistant collagenous matrix. Here, we characterise Cnidoin, a novel elastic protein identified as a structural component of Hydra Nematocysts. Cnidoin is expressed in nematocytes of all types and immunostainings revealed incorporation into capsule walls and tubules concomitant with minicollagens. Similar to spider silk proteins, to which it is related at sequence level, Cnidoin possesses high elasticity and fast coiling propensity as predicted by molecular dynamics simulations and quantified by force spectroscopy. Recombinant Cnidoin showed a high tendency for spontaneous aggregation to bundles of fibrillar structures. Cnidoin represents the molecular factor involved in kinetic energy storage and release during the ultra-fast Nematocyst discharge. Furthermore, it implies an early evolutionary origin of protein elastomers in basal metazoans.
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nematogalectin a Nematocyst protein with glyxy and galectin domains demonstrates nematocyte specific alternative splicing in hydra
Proceedings of the National Academy of Sciences of the United States of America, 2010Co-Authors: Jung Shan Hwang, Suat Ozbek, Patrizia Adamczyk, Yasuharu Takaku, Tsuyoshi Momose, Kazuho Ikeo, Konstantin Khalturin, Georg Hemmrich, Thomas C G Bosch, Thomas W HolsteinAbstract:Taxonomically restricted genes or lineage-specific genes contribute to morphological diversification in metazoans and provide unique functions for particular taxa in adapting to specific environments. To understand how such genes arise and participate in morphological evolution, we have investigated a gene called nematogalectin in Hydra, which has a structural role in the formation of Nematocysts, stinging organelles that are unique to the phylum Cnidaria. Nematogalectin is a 28-kDa protein with an N-terminal GlyXY domain (glycine followed by two hydrophobic amino acids), which can form a collagen triple helix, followed by a galactose-binding lectin domain. Alternative splicing of the nematogalectin transcript allows the gene to encode two proteins, nematogalectin A and nematogalectin B. We demonstrate that expression of nematogalectin A and B is mutually exclusive in different Nematocyst types: Desmonemes express nematogalectin B, whereas stenoteles and isorhizas express nematogalectin B early in differentiation, followed by nematogalectin A. Like Hydra, the marine hydrozoan Clytia also has two nematogalectin transcripts, which are expressed in different nematocyte types. By comparison, anthozoans have only one nematogalectin gene. Gene phylogeny indicates that tandem duplication of nematogalectin B exons gave rise to nematogalectin A before the divergence of Anthozoa and Medusozoa and that nematogalectin A was subsequently lost in Anthozoa. The emergence of nematogalectin A may have played a role in the morphological diversification of Nematocysts in the medusozoan lineage.
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evolution of complex structures minicollagens shape the cnidarian Nematocyst
Trends in Genetics, 2008Co-Authors: Charles N David, Suat Ozbek, Patrizia Adamczyk, Sebastian Meier, Barbara Pauly, Jarrod Chapman, Jung Shan Hwang, Takashi Gojobori, Thomas W HolsteinAbstract:The generation of biological complexity by the acquisition of novel modular units is an emerging concept in evolutionary dynamics. Here, we review the coordinate evolution of cnidarian Nematocysts, secretory organelles used for capture of prey, and of minicollagens, proteins constituting the Nematocyst capsule. Within the Cnidaria there is an increase in Nematocyst complexity from Anthozoa to Medusozoa and a parallel increase in the number and complexity of minicollagen proteins. This complexity is primarily manifest in a diversification of N- and C-terminal cysteine-rich domains (CRDs) involved in minicollagen polymerization. We hypothesize that novel CRD motifs alter minicollagen networks, leading to novel capsule structures and Nematocyst types.
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sequence structure and structure function analysis in cysteine rich domains forming the ultrastable Nematocyst wall
Journal of Molecular Biology, 2007Co-Authors: Sebastian Meier, Suat Ozbek, Thomas W Holstein, Patrizia Adamczyk, Hans Peter Bachinger, Jurgen Engel, Pernille Rose Jensen, Stephan GrzesiekAbstract:The Nematocyst wall of cnidarians is a unique biomaterial that withstands extreme osmotic pressures, allowing an ultrafast discharge of the Nematocyst capsules. Assembly of the highly robust Nematocyst wall is achieved by covalent linkage of cysteine-rich domains (CRDs) from two main protein components, minicollagens and Nematocyst outer wall antigen (NOWA). The bipolar minicollagens have different disulfide patterns and topologies in their N and C-terminal CRDs. The functional significance of this polarity has been elusive. Here, we show by NMR structural analysis that all representative cysteine-rich domains of NOWA are structurally related to N-terminal minicollagen domains. Natural sequence insertions in NOWA CRDs have very little effect on the tightly knit domain structures, nor do they preclude the efficient folding to a single native conformation. The different folds in NOWA CRDs and the atypical C-terminal minicollagen domain on the other hand can be directly related to different conformational preferences in the reduced states. Ultrastructural analysis in conjunction with aggregation studies argues for an association between the similar NOWA and N-terminal minicollagen domains in early stages of the Nematocyst wall assembly, which is followed by the controlled association between the unusual structures of C-terminal minicollagen domains.
Shengbao Cai - One of the best experts on this subject based on the ideXlab platform.
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partial characterization of the hemolytic activity of the Nematocyst venom from the jellyfish cyanea nozakii kishinouye
Toxicology in Vitro, 2010Co-Authors: Jinhua Feng, Ronge Xing, Song Liu, Lin Wang, Shengbao CaiAbstract:Using a recently developed technique to extract jellyfish venom from Nematocysts, the present study investigated the hemolytic activity of Cyanea nozakii Kishinouye Nematocyst venom on chicken erythrocytes. Venom extract caused a significant concentration-dependent hemolytic effect. The extract could retain its activity at -80 degrees C but was unstable when kept at 4 degrees C and -20 degrees C for 2 days. The hemolytic activity was inhibited by heating within the range of 37-100 degrees C. The extract was active over a pH range of 5.0-8.63 and the pH optima for the extract was 7.8. Incubation of the venom with sphingomyelin specially inhibited hemolytic activity by up to 70%. Cu(2+) and Mn(2+) greatly reduced the hemolytic activity while Mg(2+), Sr(2+) and Ba(2+) produced a relatively low inhibiting effect on the hemolytic activity. Treatment with Ca(2+) induced a concentration-dependent increase in the hemolytic activity. In the presence of 5 mM EDTA, all the hemolytic activity was lost, however, the venom containing 1.5 mM EDTA was stable in the long-term storage. PLA(2) activity was also found in the Nematocyst venom of C. nozakii. These characteristics provide us a fundamental knowledge in the C. nozakii Nematocyst venom which would benefit future research. (C) 2010 Published by Elsevier Ltd.
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isolation and characterization of lethal proteins in Nematocyst venom of the jellyfish cyanea nozakii kishinouye
Toxicon, 2010Co-Authors: Jinhua Feng, Ronge Xing, Song Liu, Lin Wang, Shengbao CaiAbstract:Cyanea nozakii Kishinouye, a jellyfish widely distributed in coastal areas of China, has garnered attention because of its stinging capacity and the resulting public health hazard. We used a recently developed technique to extract jellyfish venom from Nematocysts; the present study investigates the lethality of C. nozakii venom. The Nematocyst contents were extremely toxic to the grass carp, Ctenopharyngodon idellus, producing typical neurotoxin toxicity. The ID50 was about 0.6 mu g protein/g fish. Toxin samples were stable when kept at -80 degrees C, but after 48 h, an 80% decline in lethality occurred at -20 degrees C. Poor stability of the venom was observed within the range of 65-80 degrees C and at pH 3.5. The venom was hydrolyzed by a proteolytic enzyme, trypsin. Fractionation of the venom yielded two protein bands with molecular weights of 60 kDa and 50 kDa. Our results provide the first evidence that C. nozakii produces lethal toxins. These characteristics highlight the need for the isolation and molecular characterization of new active toxins in C nozakii. (C) 2009 Elsevier Ltd. All rights reserved.
David A. Hessinger - One of the best experts on this subject based on the ideXlab platform.
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effects of satiation and starvation on Nematocyst discharge prey killing and ingestion in two species of sea anemone
The Biological Bulletin, 2010Co-Authors: Glyne U Thorington, Virginia Mcauley, David A. HessingerAbstract:Studies spanning 60 years with several cnidar- ian species show that satiation inhibits prey capture and ingestion and that starvation increases prey capture and ingestion. Most have attributed the effects of satiation to inhibition of Nematocyst discharge. We hypothesized that satiation inhibits prey capture and ingestion in sea anemo- nes (Haliplanella luciae and Aiptasia pallida) primarily by inhibiting the intrinsic adherence (i.e., holding power) of discharging Nematocysts. Using a quantitative feeding assay for H. luciae, we found that satiation completely uncoupled prey killing from prey ingestion, while Nematocyst-medi- ated prey killing was only partially inhibited. Using A. pallida to measure Nematocyst discharge and Nematocyst- mediated adhesive force, we showed that satiation com- pletely inhibited the intrinsic adherence of discharging Nematocysts from Type B and Type C cnidocyte/supporting cell complexes (CSCCs), while only partially inhibiting Nematocyst discharge from Type Bs. These inhibitory ef- fects of satiation were gradually restored by starvation, reaching a maximum at 72 h after feeding. Thus, the effects of satiation and starvation on prey killing and ingestion in two species of acontiate sea anemones are primarily due to changes in the intrinsic adherence of Nematocysts from both Type B and Type C CSCCs.
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n acetylneuraminic acid nana stimulates in situ cyclic amp production in tentacles of sea anemone aiptasia pallida possible role in chemosensitization of Nematocyst discharge
The Journal of Experimental Biology, 2001Co-Authors: Haktan V Ozacmak, Glyne U Thorington, William H Fletcher, David A. HessingerAbstract:Cnidocytes, the stinging cells of cnidarians, optimally discharge Nematocysts in response to combined physical contact and stimulation of specific chemoreceptors. In the tentacles of certain sea anemones, the primary chemoreceptors bind N-acetylated sugars, such as N-acetylneuraminic acid (NANA). Sensitization with NANA predisposes contact-sensitive mechanoreceptors (CSMs) to trigger discharge in response to physical contact. In the ectoderm of sea anemone tentacles, cnidocyte/supporting cell complexes (CSCCs) control and trigger Nematocyst discharge. Previous findings have implicated cyclic AMP (cAMP) as a second messenger in NANA-sensitized Nematocyst discharge. However, no reports have directly demonstrated that the cAMP content of tentacles changes in response to NANA stimulation. We now show that NANA elevates in situ cAMP levels in a dose-dependent manner in the ectoderm of tentacles from the sea anemone Aiptasia pallida. However, the endoderm of tentacles shows no detectable cAMP response to NANA. The effect of NANA on the cAMP content of the ectoderm is biphasic. Micromolar NANA increases the in situ cAMP level, with a maximal response occurring at 1.8x10(-5)mol x l(-1) NANA. At higher NANA concentrations, the cAMP content decreases to that of controls. Because the cAMP dose/response curve to NANA coincides precisely with the dose/response curves of NANA-sensitized Nematocyst discharge and Nematocyst-mediated adhesive force, a second-messenger role for cAMP in NANA-sensitized Nematocyst discharge is strongly suggested. The addition of isobutyl-1-methylxanthine (IBMX) to the medium with sea anemones increases tissue cAMP levels both in the absence and in the presence of NANA. However, anesthetizing anemones in sea water containing high levels of Mg(2+) blocks the NANA-stimulated cAMP response of the ectoderm. In addition, our results suggest that NANA-stimulated cAMP may activate endogenous cAMP-dependent protein kinase (PKA) in broken cell preparations of tentacles. Thus, NANA-stimulated cAMP may function as a second messenger in the NANA chemosensory signaling pathway controlling Nematocyst discharge.
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efferent mechanisms of discharging cnidae ii a Nematocyst release response in the sea anemone tentacle
The Biological Bulletin, 1998Co-Authors: Glyne U Thorington, David A. HessingerAbstract:Feeding behavior in cnidarians is a sequence of coordinated responses beginning with Nematocyst discharge. The Nematocyst response produces prey capture by envenomating prey and attaching prey to the tentacle. The strength of attachment of discharged Nematocysts to the tentacle is termed intrinsic adherence and is calculated from measurements of adhesive force. Following prey capture, the feeding response involves movement of the tentacles toward the mouth and mouth opening. For ingestion to occur, Nematocysts attaching the prey to the tentacles must be released from the tentacle. A Nematocyst release response has been proposed, but never documented nor measured. Our criterion for a Nematocyst release response is that the intrinsic adherence of discharged Nematocysts must decrease to zero. The unit of Nematocyst discharge in sea anemone tentacles is the cnidocyte/ supporting cell complex (CSCC). The Nematocyst response includes Nematocysts discharged from Type C CSCCs by physical contact alone and Nematocysts discharged from the more numerous Type B CSCCs that require both chemosensitization and physical contact. We identify two prey-derived substances, N-acetylneuraminic acid (NANA) and glycine, both of which chemosensitize Nematocyst discharge from Type B CSCCs at low concentrations. At higher concentrations NANA stimulates the release response of Type Cs, and glycine stimulates the release response of Type Bs.
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antagonistic frequency tuning of hair bundles by different chemoreceptors regulates Nematocyst discharge
The Journal of Experimental Biology, 1994Co-Authors: Glen M. Watson, David A. HessingerAbstract:Sea anemones capture prey by discharging Nematocysts into them. Chemical and mechanical cues identify suitable prey to sensory receptor systems on the anemone. Conjugated N-acetylated sugars from prey bind to chemoreceptors on cnidocyte/supporting cell complexes to tune hair bundles on the complexes to lower frequencies matching prey movements. The hair bundles regulate discharge of microbasic p-mastigophore Nematocysts into vibrating targets. Provided that proline receptors are activated after those for N-acetylated sugars, Nematocyst discharge is tuned to much higher frequencies. Thus, anemone hair bundles are tuned to either higher or lower frequencies by antagonistic chemoreceptors. Chemoreceptors for proline can adapt to 10(-8) mol l-1 proline and yet respond to increases in proline concentration of less than 10(-15) mol l-1. Under these conditions, too few molecules of proline are added to activate chemoreceptors on all responding cnidocyte/supporting cell complexes. Evidence indicates that the extreme sensitivity of anemones to proline may be attributed, in part, to intercellular communication.
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Chemoreceptor-mediated elongation of stereocilium bundles tunes vibration-sensitive mechanoreceptors on cnidocyte-supporting cell complexes to lower frequencies
Journal of Cell Science, 1991Co-Authors: Glen M. Watson, David A. HessingerAbstract:Cnidocyte-supporting cell complexes (CSCCs) discharge Nematocysts into targets upon coincidental stimulation of specific chemoreceptors and contactsensitive mechanoreceptors. In addition, CSCCs in the tentacles of at least one species of sea anemone discharge Nematocysts into targets vibrating at specific frequencies. In seawater alone, these CSCCs discharge Nematocysts preferentially at 55, 50 and 75 Hz. In the presence of 10−7M N-acetylneuraminic acid (NANA) or mucin, the CSCCs discharge Nematocysts preferentially at the lower frequencies of 0, 5, 15, 30 and 40 Hz. Furthermore, the stereocilium bundles (SBs) within ciliary cones of CSCCs elongate significantly from a mean length of 6.08 μm in seawater to 7.14 μm in 10−7M mucin. The responses of (1) shifting the optimal frequencies for discharging Nematocysts to lower frequencies and (2) elongating the SBs both exhibit dose-dependency and temporal adaptation to chemosensitizer. We conclude that these responses are controlled by CSCC chemoreceptors for JV-acetylated sugars. We suggest that specific size-classes of SBs respond to specific frequencies of vibration, since the dose-response parameters to NANA depicting the relative abundances of SB size classes measuring 3–4, 5 and 7 μm correlate with dose-response parameters for the discharge of Nematocysts into targets vibrating at 75, 55, and 30 Hz. Treating tentacles with cytochalasin disorganizes the SBs of ciliary cones and decreases the number of frequency optima for Nematocyst discharge without significantly affecting Nematocyst discharge into static targets. Thus, ciliary cones on CSCCs are vibration-sensitive mechanoreceptors that can be tuned by chemoreceptors to specific, lower frequencies by the elongation of SBs.
Liming Zhang - One of the best experts on this subject based on the ideXlab platform.
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unique diversity of sting related toxins based on transcriptomic and proteomic analysis of the jellyfish cyanea capillata and nemopilema nomurai cnidaria scyphozoa
Journal of Proteome Research, 2018Co-Authors: Chao Wang, Beilei Wang, Bo Wang, Qianqian Wang, Guoyan Liu, Tao Wang, Liming ZhangAbstract:The scyphozoan jellyfish Cyanea capillata and Nemopilema nomurai are common blooming species in China. They possess heterogeneous Nematocysts and produce various types of venom that can elicit diverse sting symptoms in humans. However, the differences in venom composition between the two species remain unclear. In this study, a combined transcriptomic and proteomic approach was used to identify and compare putative toxins in penetrant Nematocysts isolated from C. capillata and N. nomurai. A total of 53 and 69 putative toxins were identified in C. capillata Nematocyst venom (CnV) and N. nomurai Nematocyst venom (NnV), respectively. These sting-related toxins from both CnV and NnV could be grouped into 10 functional categories, including proteinases, phospholipases, neurotoxins, cysteine-rich secretory proteins (CRISPs), lectins, pore-forming toxins (PFTs), protease inhibitors, ion channel inhibitors, insecticidal components, and other toxins, but the constituent ratio of each toxin category varied between CnV and NnV. Metalloproteinases, proteases, and pore-forming toxins were predominant in NnV, representing 27.5%, 18.8%, and 8.7% of the identified venom proteins, respectively, while phospholipases, neurotoxins, and proteases were the top three identified venom proteins in CnV, accounting for 22.6%, 17.0%, and 11.3%, respectively. Our findings provide comprehensive information on the molecular diversity of toxins from two common blooming and stinging species of jellyfish in China. Furthermore, the results reveal a possible relationship between venom composition and sting consequences, guiding the development of effective treatments for different jellyfish stings.
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Unique Diversity of Sting-Related Toxins Based on Transcriptomic and Proteomic Analysis of the Jellyfish Cyanea capillata and Nemopilema nomurai (Cnidaria: Scyphozoa)
2018Co-Authors: Chao Wang, Beilei Wang, Bo Wang, Qianqian Wang, Guoyan Liu, Tao Wang, Liming ZhangAbstract:The scyphozoan jellyfish Cyanea capillata and Nemopilema nomurai are common blooming species in China. They possess heterogeneous Nematocysts and produce various types of venom that can elicit diverse sting symptoms in humans. However, the differences in venom composition between the two species remain unclear. In this study, a combined transcriptomic and proteomic approach was used to identify and compare putative toxins in penetrant Nematocysts isolated from C. capillata and N. nomurai. A total of 53 and 69 putative toxins were identified in C. capillata Nematocyst venom (CnV) and N. nomurai Nematocyst venom (NnV), respectively. These sting-related toxins from both CnV and NnV could be grouped into 10 functional categories, including proteinases, phospholipases, neurotoxins, cysteine-rich secretory proteins (CRISPs), lectins, pore-forming toxins (PFTs), protease inhibitors, ion channel inhibitors, insecticidal components, and other toxins, but the constituent ratio of each toxin category varied between CnV and NnV. Metalloproteinases, proteases, and pore-forming toxins were predominant in NnV, representing 27.5%, 18.8%, and 8.7% of the identified venom proteins, respectively, while phospholipases, neurotoxins, and proteases were the top three identified venom proteins in CnV, accounting for 22.6%, 17.0%, and 11.3%, respectively. Our findings provide comprehensive information on the molecular diversity of toxins from two common blooming and stinging species of jellyfish in China. Furthermore, the results reveal a possible relationship between venom composition and sting consequences, guiding the development of effective treatments for different jellyfish stings
