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Marco Oliverio - One of the best experts on this subject based on the ideXlab platform.
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The venomous cocktail of the vampire snail Colubraria reticulata (Mollusca, Gastropoda)
BMC genomics, 2015Co-Authors: Maria Vittoria Modica, Fabrizio Lombardo, Paolo Franchini, Marco OliverioAbstract:Hematophagy arose independently multiple times during metazoan evolution, with several lineages of vampire animals particularly diversified in invertebrates. However, the biochemistry of hematophagy has been studied in a few species of direct medical interest and is still underdeveloped in most invertebrates, as in general is the study of venom toxins. In cone snails, leeches, arthropods and snakes, the strong target specificity of venom toxins uniquely aligns them to industrial and academic pursuits (pharmacological applications, pest control etc.) and provides a biochemical tool for studying biological activities including cell signalling and immunological response. Neogastropod snails (cones, oyster drills etc.) are carnivorous and include active predators, scavengers, grazers on sessile invertebrates and hematophagous parasites; most of them use venoms to efficiently feed. It has been hypothesized that trophic innovations were the main drivers of rapid radiation of Neogastropoda in the late Cretaceous. We present here the first molecular characterization of the alimentary secretion of a non-conoidean Neogastropod, Colubraria reticulata. Colubrariids successfully feed on the blood of fishes, throughout the secretion into the host of a complex mixture of anaesthetics and anticoagulants. We used a NGS RNA-Seq approach, integrated with differential expression analyses and custom searches for putative secreted feeding-related proteins, to describe in detail the salivary and mid-oesophageal transcriptomes of this Mediterranean vampire snail, with functional and evolutionary insights on major families of bioactive molecules. A remarkably low level of overlap was observed between the gene expression in the two target tissues, which also contained a high percentage of putatively secreted proteins when compared to the whole body. At least 12 families of feeding-related proteins were identified, including: 1) anaesthetics, such as ShK Toxin-containing proteins and turripeptides (ion-channel blockers), Cysteine-rich secretory proteins (CRISPs), Adenosine Deaminase (ADA); 2) inhibitors of primary haemostasis, such as novel vWFA domain-containing proteins, the Ectonucleotide pyrophosphatase/phosphodiesterase family member 5 (ENPP5) and the wasp Antigen-5; 3) anticoagulants, such as TFPI-like multiple Kunitz-type protease inhibitors, Peptidases S1 (PS1), CAP/ShKT domain-containing proteins, Astacin metalloproteases and Astacin/ShKT domain-containing proteins; 4) additional proteins, such the Angiotensin-Converting Enzyme (ACE: vasopressive) and the cytolytic Porins. Colubraria feeding physiology seems to involve inhibitors of both primary and secondary haemostasis, anaesthetics, a vasoconstrictive enzyme to reduce feeding time and tissue-degrading proteins such as Porins and Astacins. The complexity of Colubraria venomous cocktail and the divergence from the arsenal of the few Neogastropods studied to date (mostly conoideans) suggest that biochemical diversification of Neogastropods might be largely underestimated and worth of extensive investigation.
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Cellular, biochemical, and molecular characterization of nitric oxide synthase expressed in the nervous system of the prosobranch Stramonita haemastoma (Gastropoda, Neogastropoda).
The Journal of comparative neurology, 2011Co-Authors: Carla Cioni, Marco Oliverio, Maria Vittoria Modica, Maria Carmela Bonaccorsi Di Patti, Giorgio Venturini, Francesca Scarpa, Mattia ToniAbstract:Nitric oxide synthase (NOS) has been characterized in several opistobranchs and pulmonates but it was much less investigated in prosobranchs, which include more than 20,000 species and account for most of the gastropod diversity. Therefore, new data from this large group are needed for a better knowledge of the molecular evolution of NOS enzymes in molluscs. This study focused on NOS expressed in the nervous system of the prosobranch Neogastropod Stramonita haemastoma. In this study we report compelling evidence on the expression of a constitutive Ca2+/CaM-dependent neuronal NOS in the central and peripheral nervous system. The prevailing neuronal localization of NADPHd activity was demonstrated by NADPHd histochemistry in both central and peripheral nervous system structures. L-arginine/citrulline assays suggested that Stramonita NOS is a constitutive enzyme which is both cytosolic and membrane-bound. Molecular cloning of the full-length Stramonita NOS (Sh-NOS) by reverse-transcription polymerase chain reaction (RT-PCR) followed by 5′ and 3′ RACE showed that Sh-NOS is a protein of 1,517 amino acids, containing a PDZ domain at the N-terminus and sharing similar regulatory domains to the mammalian neuronal NOS (nNOS). Regional expression of the Sh-NOS gene was evaluated by RT-PCR. This analysis showed different expression levels in the nerve ring, the osphradium, the cephalic tentacles, the buccal tissues, and the foot, whereas NOS expression was not found in the salivary glands and the gland of Leiblein. The present data provide a solid background for further studies addressing the specific functions of NO in Neogastropods. J. Comp. Neurol. 520:364–383, 2012. © 2011 Wiley Periodicals, Inc.
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The relationships of the enigmatic Neogastropod Loxotaphrus (Cancellariidae)
New Zealand Journal of Geology and Geophysics, 2011Co-Authors: Maria Vittoria Modica, A Verhecken, Marco OliverioAbstract:Abstract The relationships of Loxotaphrus Harris, 1897 within Neogastropoda are discussed based on anatomical and DNA data. Sequences from 12S and 16S rDNA confirm Beu & Maxwell's placement of Loxotaphrus in the Cancellariidae, closer to Plesiotritoninae than to Cancellariinae. The nematoglossan radula of Loxotaphrus deshayesii and L. rosadoi and the elongated and spirally convoluted valve of Leiblein observed in L. deshayesii support a plesiotritonine affinity. Peculiar anatomical features include acinous rather than tubular salivary glands, accessory salivary glands fused along their posterior third and a mid-oesophageal gland placed anteriorly to the nerve ring.
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Molecular phylogeny of the nutmeg shells (Neogastropoda, Cancellariidae)
'Elsevier BV', 2011Co-Authors: Maria Vittoria Modica, Philippe Bouchet, Corinne Cruaud, Jose Utge, Marco OliverioAbstract:Cancellariidae, or nutmeg shells, is a family of marine gastropods that feed on the body fluids and the egg cases of marine animals. The 300 or so living species are distributed worldwide, mostly on soft bottoms, from intertidal to depths of about 1000 m. Although they are a key group for the understanding of Neogastropod evolution, they are still poorly known in terms of anatomy, ecology and systematics. This paper reports the first mitochondrial multi-gene phylogenetic hypothesis for the group. Data were collected for 50 morphospecies, representative of 22 genera belonging to the three currently recognized subfamilies. Sequences from three genes (125, 16S and COI) were analyzed with Maximum Likelihood analysis and Bayesian Inference, both as single gene datasets and in two partitioned concatenated alignment. Largely consistent topologies were obtained and discussed with respect to the traditional subfamilial arrangements. The obtained phylogenetic trees were also used to produce Robinson-Foulds supertrees. Our results confirmed the monophyly of the subfamily Plesiotritoninae, while Admetinae and Cancellariinae, as currently conceived, were retrieved as polyphyletic. Based on our findings we propose changes to the systematic arrangement of these subfamilies. At a lower taxonomic rank, our results highlighted the rampant homoplasy of many characters traditionally used to segregate genera, and thus the need of a critical re-evaluation of the contents of many genera (e.g. Nipponaphera, Merica, Sydaphera, Bivetia), the monophyly of which was not recovered. (C) 2011 Elsevier Inc. All rights reserved
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Relationships of the haematophagous marine snail Colubraria (Rachiglossa: Colubrariidae), within the Neogastropod phylogenetic framework
'Wiley', 2010Co-Authors: Marco Oliverio, Maria Vittoria ModicaAbstract:The gastropod genus Colubraria includes marine shallow-water species from tropical, subtropical, and temperate rocky coral environments. At least six species are known to feed on fish blood. Although there is general consensus in placing Colubraria in the Neogastropoda, the actual relationships and the systematic position of Colubraria and related genera are unknown. This is partly the consequence of the lack of a clear phylogenetic framework for the Neogastropoda. This study attempts to propose a phylogenetic framework for the Neogastropoda, by testing: (1) a preliminary phylogenetic arrangement for a large number of recognized Neogastropod families; (2) the position of Colubraria within the Neogastropods; and (3) the relationships of Colubraria within one of the major Neogastropod lineages. We used two different molecular data sets. The first set included representatives of at least 14 Neogastropod families, for points (1) and (2), and was based on mitochondrial (16S, 12S, and cytochrome oxidase subunit I, COI) and nuclear (28S) DNA sequences, giving a total of 3443 aligned positions. The second data set, for point (3), included 30 buccinoid sequences from mitochondrial 16S, giving a total of 1029 aligned positions. We also studied the anatomy of the type species of Colubraria and compared it with other Neogastropods within the new phylogenetic framework. The results included the first phylogeny of the Neogastropod based on 50% of the recognized families. This clearly indicated that the nematoglossan Cancellariidae represent a basal offshoot of the monophyletic Neogastropoda, and that the toxoglossan Conoidea are the sister group to the Rachiglossa. Within the Rachiglossa, a colubrariid clade, worthy of family ranking, showed clear buccinoid affinities. Most of the anatomy of Colubraria is congruent with a buccinoid model. The peculiar anatomical features that do not conform to the buccinoid model seem to be related to the evolution of haematophagous feeding
J. A. Jeffrey Thompson - One of the best experts on this subject based on the ideXlab platform.
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Neogastropod imposex for monitoring recovery from marine tbt contamination
Environmental Toxicology and Chemistry, 1996Co-Authors: Monica Tester, Derek V. Ellis, J. A. Jeffrey ThompsonAbstract:Imposex, the imposition of male sexual characters on female snails, was used as a bioindicator of recovery from tributyltin (TBT) pollution in the Pacific Northwest. Whelks surveyed before TBT use was regulated had shown a high frequency of affected females in the Strait of Juan de Fuca and the Strait of Georgia ; and lower frequency on the west coast of Vancouver Island. A reduction in imposex is now evident on the west coast of Vancouver Island and in some locations in the Strait of Georgia. There is no clear evidence of recovery near Victoria, and Vancouver Harbour still does not have whelks in any abundance, if at all. Of the four species studied, Nucella emarginata is the most suitable bioindicator species because it is abundantly distributed and has the shortest lifespan (1-2 years). When frequency of imposex remains at 100%, the FPL (female penis length) is still available as a useful bioindicator.
Maria Vittoria Modica - One of the best experts on this subject based on the ideXlab platform.
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The venomous cocktail of the vampire snail Colubraria reticulata (Mollusca, Gastropoda)
BMC genomics, 2015Co-Authors: Maria Vittoria Modica, Fabrizio Lombardo, Paolo Franchini, Marco OliverioAbstract:Hematophagy arose independently multiple times during metazoan evolution, with several lineages of vampire animals particularly diversified in invertebrates. However, the biochemistry of hematophagy has been studied in a few species of direct medical interest and is still underdeveloped in most invertebrates, as in general is the study of venom toxins. In cone snails, leeches, arthropods and snakes, the strong target specificity of venom toxins uniquely aligns them to industrial and academic pursuits (pharmacological applications, pest control etc.) and provides a biochemical tool for studying biological activities including cell signalling and immunological response. Neogastropod snails (cones, oyster drills etc.) are carnivorous and include active predators, scavengers, grazers on sessile invertebrates and hematophagous parasites; most of them use venoms to efficiently feed. It has been hypothesized that trophic innovations were the main drivers of rapid radiation of Neogastropoda in the late Cretaceous. We present here the first molecular characterization of the alimentary secretion of a non-conoidean Neogastropod, Colubraria reticulata. Colubrariids successfully feed on the blood of fishes, throughout the secretion into the host of a complex mixture of anaesthetics and anticoagulants. We used a NGS RNA-Seq approach, integrated with differential expression analyses and custom searches for putative secreted feeding-related proteins, to describe in detail the salivary and mid-oesophageal transcriptomes of this Mediterranean vampire snail, with functional and evolutionary insights on major families of bioactive molecules. A remarkably low level of overlap was observed between the gene expression in the two target tissues, which also contained a high percentage of putatively secreted proteins when compared to the whole body. At least 12 families of feeding-related proteins were identified, including: 1) anaesthetics, such as ShK Toxin-containing proteins and turripeptides (ion-channel blockers), Cysteine-rich secretory proteins (CRISPs), Adenosine Deaminase (ADA); 2) inhibitors of primary haemostasis, such as novel vWFA domain-containing proteins, the Ectonucleotide pyrophosphatase/phosphodiesterase family member 5 (ENPP5) and the wasp Antigen-5; 3) anticoagulants, such as TFPI-like multiple Kunitz-type protease inhibitors, Peptidases S1 (PS1), CAP/ShKT domain-containing proteins, Astacin metalloproteases and Astacin/ShKT domain-containing proteins; 4) additional proteins, such the Angiotensin-Converting Enzyme (ACE: vasopressive) and the cytolytic Porins. Colubraria feeding physiology seems to involve inhibitors of both primary and secondary haemostasis, anaesthetics, a vasoconstrictive enzyme to reduce feeding time and tissue-degrading proteins such as Porins and Astacins. The complexity of Colubraria venomous cocktail and the divergence from the arsenal of the few Neogastropods studied to date (mostly conoideans) suggest that biochemical diversification of Neogastropods might be largely underestimated and worth of extensive investigation.
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Cellular, biochemical, and molecular characterization of nitric oxide synthase expressed in the nervous system of the prosobranch Stramonita haemastoma (Gastropoda, Neogastropoda).
The Journal of comparative neurology, 2011Co-Authors: Carla Cioni, Marco Oliverio, Maria Vittoria Modica, Maria Carmela Bonaccorsi Di Patti, Giorgio Venturini, Francesca Scarpa, Mattia ToniAbstract:Nitric oxide synthase (NOS) has been characterized in several opistobranchs and pulmonates but it was much less investigated in prosobranchs, which include more than 20,000 species and account for most of the gastropod diversity. Therefore, new data from this large group are needed for a better knowledge of the molecular evolution of NOS enzymes in molluscs. This study focused on NOS expressed in the nervous system of the prosobranch Neogastropod Stramonita haemastoma. In this study we report compelling evidence on the expression of a constitutive Ca2+/CaM-dependent neuronal NOS in the central and peripheral nervous system. The prevailing neuronal localization of NADPHd activity was demonstrated by NADPHd histochemistry in both central and peripheral nervous system structures. L-arginine/citrulline assays suggested that Stramonita NOS is a constitutive enzyme which is both cytosolic and membrane-bound. Molecular cloning of the full-length Stramonita NOS (Sh-NOS) by reverse-transcription polymerase chain reaction (RT-PCR) followed by 5′ and 3′ RACE showed that Sh-NOS is a protein of 1,517 amino acids, containing a PDZ domain at the N-terminus and sharing similar regulatory domains to the mammalian neuronal NOS (nNOS). Regional expression of the Sh-NOS gene was evaluated by RT-PCR. This analysis showed different expression levels in the nerve ring, the osphradium, the cephalic tentacles, the buccal tissues, and the foot, whereas NOS expression was not found in the salivary glands and the gland of Leiblein. The present data provide a solid background for further studies addressing the specific functions of NO in Neogastropods. J. Comp. Neurol. 520:364–383, 2012. © 2011 Wiley Periodicals, Inc.
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The relationships of the enigmatic Neogastropod Loxotaphrus (Cancellariidae)
New Zealand Journal of Geology and Geophysics, 2011Co-Authors: Maria Vittoria Modica, A Verhecken, Marco OliverioAbstract:Abstract The relationships of Loxotaphrus Harris, 1897 within Neogastropoda are discussed based on anatomical and DNA data. Sequences from 12S and 16S rDNA confirm Beu & Maxwell's placement of Loxotaphrus in the Cancellariidae, closer to Plesiotritoninae than to Cancellariinae. The nematoglossan radula of Loxotaphrus deshayesii and L. rosadoi and the elongated and spirally convoluted valve of Leiblein observed in L. deshayesii support a plesiotritonine affinity. Peculiar anatomical features include acinous rather than tubular salivary glands, accessory salivary glands fused along their posterior third and a mid-oesophageal gland placed anteriorly to the nerve ring.
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Molecular phylogeny of the nutmeg shells (Neogastropoda, Cancellariidae)
'Elsevier BV', 2011Co-Authors: Maria Vittoria Modica, Philippe Bouchet, Corinne Cruaud, Jose Utge, Marco OliverioAbstract:Cancellariidae, or nutmeg shells, is a family of marine gastropods that feed on the body fluids and the egg cases of marine animals. The 300 or so living species are distributed worldwide, mostly on soft bottoms, from intertidal to depths of about 1000 m. Although they are a key group for the understanding of Neogastropod evolution, they are still poorly known in terms of anatomy, ecology and systematics. This paper reports the first mitochondrial multi-gene phylogenetic hypothesis for the group. Data were collected for 50 morphospecies, representative of 22 genera belonging to the three currently recognized subfamilies. Sequences from three genes (125, 16S and COI) were analyzed with Maximum Likelihood analysis and Bayesian Inference, both as single gene datasets and in two partitioned concatenated alignment. Largely consistent topologies were obtained and discussed with respect to the traditional subfamilial arrangements. The obtained phylogenetic trees were also used to produce Robinson-Foulds supertrees. Our results confirmed the monophyly of the subfamily Plesiotritoninae, while Admetinae and Cancellariinae, as currently conceived, were retrieved as polyphyletic. Based on our findings we propose changes to the systematic arrangement of these subfamilies. At a lower taxonomic rank, our results highlighted the rampant homoplasy of many characters traditionally used to segregate genera, and thus the need of a critical re-evaluation of the contents of many genera (e.g. Nipponaphera, Merica, Sydaphera, Bivetia), the monophyly of which was not recovered. (C) 2011 Elsevier Inc. All rights reserved
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The Neogastropoda: Evolutionary Innovations of Predatory Marine Snails with Remarkable Pharmacological Potential
Evolutionary Biology – Concepts Molecular and Morphological Evolution, 2010Co-Authors: Maria Vittoria Modica, Mandë HolfordAbstract:The Neogastropoda include many familiar molluscs, such as cone snails (Conidae), purple dye snails (Muricidae), mud snails (Nassariidae), olive snails (Olividae), oyster drills (Muricidae), tulip shells (Fasciolariidae), and whelks (Buccinidae). Due to their amazing predatory specializations, Neogastropods are often dominant members of the benthic community at the top of the food chain. In a dazzling display that ranges from boring holes to darting harpoons, Neogastropods have developed several prey hunting innovations with specialized compounds pharmaceutical companies could only dream about. It has been hypothesized that evolutionary innovations related to feeding were the main drivers of the rapid Neogastropod radiation in the late Cretaceous. The anatomical, behavioral, and biochemical specializations of Neogastropod families that are promising targets in drug discovery and development are addressed within an evolutionary framework in this chapter.
Jeffery Spickett - One of the best experts on this subject based on the ideXlab platform.
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Imposex in Morula Granulata as Bioindicator of Tributyltin (TBT) Contamination in the Dampier Archipelago, Western Australia
Marine Pollution Bulletin, 1999Co-Authors: Tarren J. Reitsema, Jeffery SpickettAbstract:Abstract This study was undertaken to examine the use of imposex in the tropical Neogastropod whelk Morula granulata as bioindicator of tributyltin (TBT) contamination. Samples were collected from sites throughout the Dampier Archipelago; both impact sites close to intensive shipping activity and remote control sites. TBT in this area originates mainly from commercial vessels using the Port of Dampier that are >25 m in length and exempt from legislation controlling the use of TBT in antifouling paints. A field survey was undertaken in July 1997; 100 M. granulata were taken at each of 18 sites with varying vessel activity, and examined for imposex. The level of TBT contamination in the Archipelago was low; ranging from
M. C. Miller - One of the best experts on this subject based on the ideXlab platform.
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Imposex in New Zealand Neogastropods
Marine Pollution Bulletin, 1992Co-Authors: Carol Stewart, S. J. De Mora, M. R. L. Jones, M. C. MillerAbstract:Abstract Imposex has been observed in the New Zealand Neogastropod species Lepsiella scobina; Thais orbita; Haustrum haustorium; Xymene ambiguus; Taron dubius; Cominella virgata and Amalda (Baryspira) australis. Imposex occurrence in L. scobina has been studied in more detail in the Auckland region, and the sequence of imposex development described. At 3 control sites, 0% frequency of imposex was observed, but at all other sites 100% frequency of imposex was recorded. Lepsiella scobina populations in the inner Waitemata Harbour were found to be severely imposexed, and appear to be in decline. A relationship was found to exist between imposex intensity (as measured by the Vas Deferens Sequence Index) and L. scobina body burdens of hexane-extractable tin. Lepsiella scobina shows considerable potential as a bioindicator species of TBT contamination in New Zealand coastal waters, due to its acute sensitivity to TBT, intertidal occurrence, widespread distribution, high abundance, direct development and limited adult mobility.
