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Arthropod venoms: Biochemistry, ecology and evolution. Toxicon 2018; 158:84-103. [PMID: 30529476 DOI: 10.1016/j.toxicon.2018.11.433] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 11/20/2018] [Accepted: 11/26/2018] [Indexed: 12/17/2022]
Abstract
Comprising of over a million described species of highly diverse invertebrates, Arthropoda is amongst the most successful animal lineages to have colonized aerial, terrestrial, and aquatic domains. Venom, one of the many fascinating traits to have evolved in various members of this phylum, has underpinned their adaptation to diverse habitats. Over millions of years of evolution, arthropods have evolved ingenious ways of delivering venom in their targets for self-defence and predation. The morphological diversity of venom delivery apparatus in arthropods is astounding, and includes extensively modified pedipalps, tail (telson), mouth parts (hypostome), fangs, appendages (maxillulae), proboscis, ovipositor (stinger), and hair (urticating bristles). Recent investigations have also unravelled an astonishing venom biocomplexity with molecular scaffolds being recruited from a multitude of protein families. Venoms are a remarkable bioresource for discovering lead compounds in targeted therapeutics. Several components with prospective applications in the development of advanced lifesaving drugs and environment friendly bio-insecticides have been discovered from arthropod venoms. Despite these fascinating features, the composition, bioactivity, and molecular evolution of venom in several arthropod lineages remains largely understudied. This review highlights the prevalence of venom, its mode of toxic action, and the evolutionary dynamics of venom in Arthropoda, the most speciose phylum in the animal kingdom.
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Junqueira-de-Azevedo ILM, Campos PF, Ching ATC, Mackessy SP. Colubrid Venom Composition: An -Omics Perspective. Toxins (Basel) 2016; 8:E230. [PMID: 27455326 PMCID: PMC4999846 DOI: 10.3390/toxins8080230] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 07/04/2016] [Accepted: 07/08/2016] [Indexed: 01/12/2023] Open
Abstract
Snake venoms have been subjected to increasingly sensitive analyses for well over 100 years, but most research has been restricted to front-fanged snakes, which actually represent a relatively small proportion of extant species of advanced snakes. Because rear-fanged snakes are a diverse and distinct radiation of the advanced snakes, understanding venom composition among "colubrids" is critical to understanding the evolution of venom among snakes. Here we review the state of knowledge concerning rear-fanged snake venom composition, emphasizing those toxins for which protein or transcript sequences are available. We have also added new transcriptome-based data on venoms of three species of rear-fanged snakes. Based on this compilation, it is apparent that several components, including cysteine-rich secretory proteins (CRiSPs), C-type lectins (CTLs), CTLs-like proteins and snake venom metalloproteinases (SVMPs), are broadly distributed among "colubrid" venoms, while others, notably three-finger toxins (3FTxs), appear nearly restricted to the Colubridae (sensu stricto). Some putative new toxins, such as snake venom matrix metalloproteinases, are in fact present in several colubrid venoms, while others are only transcribed, at lower levels. This work provides insights into the evolution of these toxin classes, but because only a small number of species have been explored, generalizations are still rather limited. It is likely that new venom protein families await discovery, particularly among those species with highly specialized diets.
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Affiliation(s)
- Inácio L M Junqueira-de-Azevedo
- Laboratório Especial de Toxinologia Aplicada, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo 05503-900, Brazil.
| | - Pollyanna F Campos
- Laboratório Especial de Toxinologia Aplicada, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo 05503-900, Brazil.
| | - Ana T C Ching
- Laboratório de Imunoquímica, Instituto Butantan, São Paulo 05503-900, Brazil.
| | - Stephen P Mackessy
- School of Biological Sciences, University of Northern Colorado, Greeley, CO 80639-0017, USA.
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Arcos-Hernández C, Romero F, Sánchez-Guevara Y, Beltrán C, Nishigaki T. FRET analysis using sperm-activating peptides tagged with fluorescent proteins reveals that ligand-binding sites exist as clusters. ACTA ACUST UNITED AC 2016; 219:508-15. [PMID: 26889001 DOI: 10.1242/jeb.127662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Long-range cellular communication between the sperm and egg is critical for external fertilization. Sperm-activating peptides (SAPs) are diffusible components of the outer layer of eggs in echinoderms, and function as chemoattractants for spermatozoa. The decapeptide named speract is the best-characterized sea urchin SAP. Biochemical and physiological actions of speract have been studied with purified or chemically synthesized peptides. In this work, we prepared recombinant speract fused to a fluorescent protein (FP; FP-speract) using three color variants: a cyan (eCFP), a yellow (mVenus) and a large Stokes shift yellow (mAmetrine) FP. Although these fluorescence tags are 20 times larger than speract, competitive binding experiments using mAmetrine-speract revealed that this FP-speract has binding affinity to the receptor that is comparable (7.6-fold less) to that of non-labeled speract. Indeed, 10 nmol l(-1) eCFP-speract induces physiological sperm responses such as membrane potential changes and increases in intracellular pH and Ca(2+) concentrations similar to those triggered by 10 nmol l(-1) speract. Furthermore, FP-speract maintains its fluorescence upon binding to its receptor. Using this property, we performed fluorescence resonance energy transfer (FRET) measurements with eCFP-speract and mVenus-speract as probes and obtained a positive FRET signal upon binding to the receptor, which suggests that the speract receptor exists as an oligomer, at least as a dimer, or alternatively that a single speract receptor protein possesses multiple binding sites. This property could partially account for the positive and/or negative cooperative binding of speract to the receptor.
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Affiliation(s)
- César Arcos-Hernández
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (IBT-UNAM), Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Mor. 62210, Mexico
| | - Francisco Romero
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (IBT-UNAM), Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Mor. 62210, Mexico
| | - Yoloxochitl Sánchez-Guevara
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (IBT-UNAM), Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Mor. 62210, Mexico
| | - Carmen Beltrán
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (IBT-UNAM), Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Mor. 62210, Mexico
| | - Takuya Nishigaki
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (IBT-UNAM), Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Mor. 62210, Mexico
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Reyes-Velasco J, Card DC, Andrew AL, Shaney KJ, Adams RH, Schield DR, Casewell NR, Mackessy SP, Castoe TA. Expression of venom gene homologs in diverse python tissues suggests a new model for the evolution of snake venom. Mol Biol Evol 2014; 32:173-83. [PMID: 25338510 DOI: 10.1093/molbev/msu294] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Snake venom gene evolution has been studied intensively over the past several decades, yet most previous studies have lacked the context of complete snake genomes and the full context of gene expression across diverse snake tissues. We took a novel approach to studying snake venom evolution by leveraging the complete genome of the Burmese python, including information from tissue-specific patterns of gene expression. We identified the orthologs of snake venom genes in the python genome, and conducted detailed analysis of gene expression of these venom homologs to identify patterns that differ between snake venom gene families and all other genes. We found that venom gene homologs in the python are expressed in many different tissues outside of oral glands, which illustrates the pitfalls of using transcriptomic data alone to define "venom toxins." We hypothesize that the python may represent an ancestral state prior to major venom development, which is supported by our finding that the expansion of venom gene families is largely restricted to highly venomous caenophidian snakes. Therefore, the python provides insight into biases in which genes were recruited for snake venom systems. Python venom homologs are generally expressed at lower levels, have higher variance among tissues, and are expressed in fewer organs compared with all other python genes. We propose a model for the evolution of snake venoms in which venom genes are recruited preferentially from genes with particular expression profile characteristics, which facilitate a nearly neutral transition toward specialized venom system expression.
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Affiliation(s)
| | - Daren C Card
- Department of Biology, University of Texas at Arlington
| | | | - Kyle J Shaney
- Department of Biology, University of Texas at Arlington
| | | | | | - Nicholas R Casewell
- Alistair Reid Venom Research Unit, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | - Todd A Castoe
- Department of Biology, University of Texas at Arlington
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Multifunctional warheads: Diversification of the toxin arsenal of centipedes via novel multidomain transcripts. J Proteomics 2014; 102:1-10. [DOI: 10.1016/j.jprot.2014.02.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Revised: 02/19/2014] [Accepted: 02/21/2014] [Indexed: 11/22/2022]
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Abstract
Venoms are evolutionarily fine-tuned mixtures of small molecules, peptides, and proteins-referred to as toxins-that have evolved to specifically modulate and interfere with the function of diverse molecular targets within the envenomated animal. Many of the identified toxin targets are membrane receptors and ion channels. Due to their high specificity, toxins have emerged as an invaluable tool set for the molecular characterization of ion channels, and a selected group of toxins even have been developed into therapeutics. More recently, TRP ion channels have been included as targets for venomous toxins. In particular, a number of apparently unrelated peptide toxins target the capsaicin receptor TRPV1 to produce inflammatory pain. These toxins have turned out to be invaluable for structural and functional characterizations of the capsaicin receptor. If toxins will serve similar roles for other TRP ion channels, only future will tell.
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Affiliation(s)
- Jan Siemens
- Department of Pharmacology, University Clinic Heidelberg, Im Neuenheimer Feld 366, 69120, Heidelberg, Germany,
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Atractaspis aterrima toxins: the first insight into the molecular evolution of venom in side-stabbers. Toxins (Basel) 2013; 5:1948-64. [PMID: 24169588 PMCID: PMC3847709 DOI: 10.3390/toxins5111948] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 10/19/2013] [Accepted: 10/22/2013] [Indexed: 12/13/2022] Open
Abstract
Although snake venoms have been the subject of intense research, primarily because of their tremendous potential as a bioresource for design and development of therapeutic compounds, some specific groups of snakes, such as the genus Atractaspis, have been completely neglected. To date only limited number of toxins, such as sarafotoxins have been well characterized from this lineage. In order to investigate the molecular diversity of venom from Atractaspis aterrima—the slender burrowing asp, we utilized a high-throughput transcriptomic approach completed with an original bioinformatics analysis pipeline. Surprisingly, we found that Sarafotoxins do not constitute the major ingredient of the transcriptomic cocktail; rather a large number of previously well-characterized snake venom-components were identified. Notably, we recovered a large diversity of three-finger toxins (3FTxs), which were found to have evolved under the significant influence of positive selection. From the normalized and non-normalized transcriptome libraries, we were able to evaluate the relative abundance of the different toxin groups, uncover rare transcripts, and gain new insight into the transcriptomic machinery. In addition to previously characterized toxin families, we were able to detect numerous highly-transcribed compounds that possess all the key features of venom-components and may constitute new classes of toxins.
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Abstract
Venoms and toxins are of significant interest due to their ability to cause a wide range of pathophysiological conditions that can potentially result in death. Despite their wide distribution among plants and animals, the biochemical pathways associated with these pathogenic agents remain largely unexplored. Impoverished and underdeveloped regions appear especially susceptible to increased incidence and severity due to poor socioeconomic conditions and lack of appropriate medical treatment infrastructure. To facilitate better management and treatment of envenomation victims, it is essential that the biochemical mechanisms of their action be elucidated. This review aims to characterize downstream envenomation mechanisms by addressing the major neuro-, cardio-, and hemotoxins as well as ion-channel toxins. Because of their use in folk and traditional medicine, the biochemistry behind venom therapy and possible implications on conventional medicine will also be addressed.
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Camargo ACM, Fernandes BL, Cruz L, Ferro ES. Bioactive Peptides Produced by Limited Proteolysis. ACTA ACUST UNITED AC 2012. [DOI: 10.4199/c00056ed1v01y201204npe002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Bohlen CJ, Julius D. Receptor-targeting mechanisms of pain-causing toxins: How ow? Toxicon 2012; 60:254-64. [PMID: 22538196 DOI: 10.1016/j.toxicon.2012.04.336] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 04/04/2012] [Indexed: 12/15/2022]
Abstract
Venoms often target vital processes to cause paralysis or death, but many types of venom also elicit notoriously intense pain. While these pain-producing effects can result as a byproduct of generalized tissue trauma, there are now multiple examples of venom-derived toxins that target somatosensory nerve terminals in order to activate nociceptive (pain-sensing) neural pathways. Intriguingly, investigation of the venom components that are responsible for evoking pain has revealed novel roles and/or configurations of well-studied toxin motifs. This review serves to highlight pain-producing toxins that target the capsaicin receptor, TRPV1, or members of the acid-sensing ion channel family, and to discuss the utility of venom-derived multivalent and multimeric complexes.
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Affiliation(s)
- Christopher J Bohlen
- Department of Physiology, University of California, San Francisco, CA 94158-2517, USA.
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Wong ES, Belov K. Venom evolution through gene duplications. Gene 2012; 496:1-7. [DOI: 10.1016/j.gene.2012.01.009] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 01/10/2012] [Accepted: 01/10/2012] [Indexed: 12/30/2022]
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Wong ESW, Papenfuss AT, Whittington CM, Warren WC, Belov K. A limited role for gene duplications in the evolution of platypus venom. Mol Biol Evol 2011; 29:167-77. [PMID: 21816864 DOI: 10.1093/molbev/msr180] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Gene duplication followed by adaptive selection is believed to be the primary driver of venom evolution. However, to date, no studies have evaluated the importance of gene duplications for venom evolution using a genomic approach. The availability of a sequenced genome and a venom gland transcriptome for the enigmatic platypus provides a unique opportunity to explore the role that gene duplication plays in venom evolution. Here, we identify gene duplication events and correlate them with expressed transcripts in an in-season venom gland. Gene duplicates (1,508) were identified. These duplicated pairs (421), including genes that have undergone multiple rounds of gene duplications, were expressed in the venom gland. The majority of these genes are involved in metabolism and protein synthesis not toxin functions. Twelve secretory genes including serine proteases, metalloproteinases, and protease inhibitors likely to produce symptoms of envenomation such as vasodilation and pain were detected. Only 16 of 107 platypus genes with high similarity to known toxins evolved through gene duplication. Platypus venom C-type natriuretic peptides and nerve growth factor do not possess lineage-specific gene duplicates. Extensive duplications, believed to increase the potency of toxic content and promote toxin diversification, were not found. This is the first study to take a genome-wide approach in order to examine the impact of gene duplication on venom evolution. Our findings support the idea that adaptive selection acts on gene duplicates to drive the independent evolution and functional diversification of similar venom genes in venomous species. However, gene duplications alone do not explain the "venome" of the platypus. Other mechanisms, such as alternative splicing and mutation, may be important in venom innovation.
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Affiliation(s)
- Emily S W Wong
- Faculty of Veterinary Science, The University of Sydney, Sydney, New South Wales, Australia.
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Casewell NR, Wagstaff SC, Harrison RA, Renjifo C, Wuster W. Domain Loss Facilitates Accelerated Evolution and Neofunctionalization of Duplicate Snake Venom Metalloproteinase Toxin Genes. Mol Biol Evol 2011; 28:2637-49. [DOI: 10.1093/molbev/msr091] [Citation(s) in RCA: 121] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Fry BG, Roelants K, Winter K, Hodgson WC, Griesman L, Kwok HF, Scanlon D, Karas J, Shaw C, Wong L, Norman JA. Novel venom proteins produced by differential domain-expression strategies in beaded lizards and gila monsters (genus Heloderma). Mol Biol Evol 2009; 27:395-407. [PMID: 19837656 DOI: 10.1093/molbev/msp251] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The origin and evolution of venom proteins in helodermatid lizards were investigated by multidisciplinary techniques. Our analyses elucidated novel toxin types resultant from three unique domain-expression processes: 1) The first full-length sequences of lethal toxin isoforms (helofensins) revealed this toxin type to be constructed by an ancestral monodomain, monoproduct gene (beta-defensin) that underwent three tandem domain duplications to encode a tetradomain, monoproduct with a possible novel protein fold; 2) an ancestral monodomain gene (encoding a natriuretic peptide) was medially extended to become a pentadomain, pentaproduct through the additional encoding of four tandemly repeated proline-rich peptides (helokinestatins), with the five discrete peptides liberated from each other by posttranslational proteolysis; and 3) an ancestral multidomain, multiproduct gene belonging to the vasoactive intestinal peptide (VIP)/glucagon family being mutated to encode for a monodomain, monoproduct (exendins) followed by duplication and diversification into two variant classes (exendins 1 and 2 and exendins 3 and 4). Bioactivity characterization of exendin and helokinestatin elucidated variable cardioactivity between isoforms within each class. These results highlight the importance of utilizing evolutionary-based search strategies for biodiscovery and the virtually unexplored potential of lizard venoms in drug design and discovery.
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Affiliation(s)
- Bryan G Fry
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia.
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Lauer-Fields JL, Cudic M, Wei S, Mari F, Fields GB, Brew K. Engineered sarafotoxins as tissue inhibitor of metalloproteinases-like matrix metalloproteinase inhibitors. J Biol Chem 2007; 282:26948-26955. [PMID: 17626018 DOI: 10.1074/jbc.m611612200] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The sarafotoxins and endothelins are approximately 25-residue peptides that spontaneously fold into a defined tertiary structure with specific pairing of four cysteines into two disulfide bonds. Their structures show an interesting topological similarity to the core of the metalloproteinase interaction sites of the tissue inhibitors of metalloproteinases. Previous work indicates that sarafotoxins and endothelins can be engineered to eliminate or greatly reduce their vasopressive action and that their structural framework can withstand multiple sequence changes. When sarafotoxin 6b, which possesses modest matrix metalloproteinase inhibitory activity, was C-terminally truncated to remove its toxic vasopressive activity, the metalloproteinase inhibitory activity was essentially abolished. However, further changes, based on the sequences of peptides selected from libraries of sarafotoxin variants or suggested by analogy with tissue inhibitors of metalloproteinases, progressively enhanced the matrix metalloproteinase inhibitory activity. Peptide variants with multiple substitutions folded correctly and formed native disulfide bonds. Improvements in matrix metalloproteinase affinity have generated a peptide with micromolar K(i) values for matrix metalloproteinase-1 and -9 that are selective inhibitors of different metalloproteinases. Characterization of its solution structure indicates a close similarity to sarafotoxin but with a more extended C-terminal helix. The effects of N-acetylation and other changes, as well as docking studies, support the hypothesis that the engineered sarafotoxins bind to matrix metalloproteinases in a manner analogous to the tissue inhibitors of metalloproteinases.
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Affiliation(s)
- Janelle L Lauer-Fields
- College of Biomedical Science, Florida Atlantic University, Boca Raton, Florida 33431; Department of Chemistry & Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431
| | - Mare Cudic
- Department of Chemistry & Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431
| | - Shuo Wei
- College of Biomedical Science, Florida Atlantic University, Boca Raton, Florida 33431
| | - Frank Mari
- Department of Chemistry & Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431
| | - Gregg B Fields
- Department of Chemistry & Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431
| | - Keith Brew
- College of Biomedical Science, Florida Atlantic University, Boca Raton, Florida 33431.
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Breno MC, Prezoto BC, Borgheresi RAMB, Lazari MFM, Yamanouye N. Characteristics of neural and humoral systems involved in the regulation of blood pressure in snakes. Comp Biochem Physiol A Mol Integr Physiol 2007; 147:766-778. [PMID: 17046304 DOI: 10.1016/j.cbpa.2006.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Revised: 09/04/2006] [Accepted: 09/05/2006] [Indexed: 12/22/2022]
Abstract
Cardiovascular function is affected by many mechanisms, including the autonomic system, the kallikrein-kinin system (KKS), the renin-angiotensin system (RAS) and the endothelin system. The function of these systems seems to be fairly well preserved throughout the vertebrate scale, but evolution required several adaptations. Snakes are particularly interesting for studies related to the cardiovascular function because of their elongated shape, their wide variation in size and length, and because they had to adapt to extremely different habitats and gravitational influences. To keep the normal cardiovascular control the snakes developed anatomical and functional adaptations and interesting structural peculiarities are found in their autonomic, KKS, RAS and endothelin systems. Our laboratory has characterized some biochemical, pharmacological and physiological properties of these systems in South American snakes. This review compares the components and function of these systems in snakes and other vertebrates, and focuses on differences found in snakes, related with receptor or ligand structure and/or function in autonomic system, RAS and KKS, absence of components in KKS and the intriguing identity between a venom and a plasma component in the endothelin system.
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Affiliation(s)
- Maria Cristina Breno
- Laboratório de Farmacologia, Instituto Butantan, Av. Vital Brazil, 1500, 05503-900, São Paulo, SP, Brazil.
| | - Benedito Carlos Prezoto
- Laboratório de Farmacologia, Instituto Butantan, Av. Vital Brazil, 1500, 05503-900, São Paulo, SP, Brazil
| | - Rosa A M B Borgheresi
- Laboratório de Farmacologia, Instituto Butantan, Av. Vital Brazil, 1500, 05503-900, São Paulo, SP, Brazil
| | - Maria Fátima M Lazari
- Departamento de Farmacologia, Setor Endocrinologia Experimental, Universidade Federal de São Paulo, Rua 3 de maio,100, 04044-020, São Paulo, SP, Brazil
| | - Norma Yamanouye
- Laboratório de Farmacologia, Instituto Butantan, Av. Vital Brazil, 1500, 05503-900, São Paulo, SP, Brazil
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Quinton L, Le Caer JP, Phan G, Ligny-Lemaire C, Bourdais-Jomaron J, Ducancel F, Chamot-Rooke J. Characterization of Toxins within Crude Venoms by Combined Use of Fourier Transform Mass Spectrometry and Cloning. Anal Chem 2005; 77:6630-9. [PMID: 16223250 DOI: 10.1021/ac050575k] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The standard analytical procedure for screening the proteomic profile of a venom often relies on an appropriate combination of sample extraction, electrophoresis, reversed-phase high-performance liquid chromatography, mass spectrometry, and Edman degradation. We present in this study a new approach for venom screening based on Fourier transform mass spectrometry (FTMS) analysis directly on the crude venom. The venom chosen is a unique sample from Atractaspis irregularis, a species never studied at the molecular level previously. This snake belongs to the Atractaspidae family that is known to produce highly toxic venoms containing endothelin-like peptides called sarafotoxins (SRTXs). Nanoelectrospray-FTMS spectrum of the crude venom allowed the identification of 60 distinct compounds with molecular masses from 600 to 14,000 Da, which would have been impossible without the resolution of this kind of instrument. De novo sequencing within the entire venom confirmed the sequences of two new families of sarafotoxins, whose precursors had been cloned, and allowed the characterization of a third one. One particularly interesting point was that the propolypeptides appeared processed not in one unique compound, but rather in different length molecules ranging from 15 for the shorter to 30 amino acids for the longer. Moreover, our results clearly establish that in the case of A. irregularis only one copy of mature sarafotoxin emerges from each precursor, which is a totally different organization in comparison of other precursors of SRTXs.
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Affiliation(s)
- Loïc Quinton
- Laboratoire des Mécanismes Réactionnels, UMR 7651 CNRS, Ecole Polytechnique, F-91128, Palaiseau, France
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Hayashi MAF, Camargo ACM. The Bradykinin-potentiating peptides from venom gland and brain of Bothrops jararaca contain highly site specific inhibitors of the somatic angiotensin-converting enzyme. Toxicon 2005; 45:1163-70. [PMID: 15922781 DOI: 10.1016/j.toxicon.2005.02.017] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Pyroglutamyl, proline-rich oligopeptides, classically referred to as bradykinin-potentiating peptides (BPPs) are found in Bothrops jararaca venom, and are naturally occurring inhibitors of the somatic angiotensin-converting enzyme (ACE). The chemical and pharmacological properties of these peptides were essential for the development of captopril, the first active site directed inhibitor of ACE, currently used to treat human hypertension. ACE is a complex ectoenzyme of the vascular endothelium, possessing two catalytic sites, performing diverse specific roles. Recent advances concerning novel features of BPPs revealed that they might still contribute to a better understanding of the cardiovascular physiology and pathology. The molecular biology of the BPPs revealed that they are part of two distinct C-type natriuretic peptide precursors found in the venom gland and the brain of B. jararaca, each containing seven BPPs. In situ hybridization studies detected the presence of the corresponding mRNA precursor in snake brain regions correlated with neuroendocrine functions, such as the ventro-medial hypothalamus, the paraventricular nuclei, the paraventricular organ, and the subcommissural organ. In this article we discuss the large variety of homologous BPPs in B. jararaca venom and brain, its significance, and whether the BPPs could represent novel endogenous neuropeptides.
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Affiliation(s)
- Mirian A F Hayashi
- Center for Applied Toxinology-CAT/CEPID, Instituto Butantan, Av. Vital Brasil 1500, São Paulo, SP 05503-900, Brazil
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Fry BG. From genome to "venome": molecular origin and evolution of the snake venom proteome inferred from phylogenetic analysis of toxin sequences and related body proteins. Genome Res 2005; 15:403-20. [PMID: 15741511 PMCID: PMC551567 DOI: 10.1101/gr.3228405] [Citation(s) in RCA: 365] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This study analyzed the origin and evolution of snake venom proteome by means of phylogenetic analysis of the amino acid sequences of the toxins and related nonvenom proteins. The snake toxins were shown to have arisen from recruitment events of genes from within the following protein families: acetylcholinesterase, ADAM (disintegrin/metalloproteinase), AVIT, complement C3, crotasin/beta defensin, cystatin, endothelin, factor V, factor X, kallikrein, kunitz-type proteinase inhibitor, LYNX/SLUR, L-amino oxidase, lectin, natriuretic peptide, betanerve growth factor, phospholipase A(2), SPla/Ryanodine, vascular endothelial growth factor, and whey acidic protein/secretory leukoproteinase inhibitor. Toxin recruitment events were found to have occurred at least 24 times in the evolution of snake venom. Two of these toxin derivations (CRISP and kallikrein toxins) appear to have been actually the result of modifications of existing salivary proteins rather than gene recruitment events. One snake toxin type, the waglerin peptides from Tropidolaemus wagleri (Wagler's Viper), did not have a match with known proteins and may be derived from a uniquely reptilian peptide. All of the snake toxin types still possess the bioactivity of the ancestral proteins in at least some of the toxin isoforms. However, this study revealed that the toxin types, where the ancestral protein was extensively cysteine cross-linked, were the ones that flourished into functionally diverse, novel toxin multigene families.
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Affiliation(s)
- Bryan G Fry
- Australian Venom Research Unit, Level 8, School of Medicine, University of Melbourne, Parkville, Victoria 3010 Australia.
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20
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Hayashi MAF, Ligny-Lemaire C, Wollberg Z, Wery M, Galat A, Ogawa T, Muller BH, Lamthanh H, Doljansky Y, Bdolah A, Stöcklin R, Ducancel F. Long-sarafotoxins: characterization of a new family of endothelin-like peptides. Peptides 2004; 25:1243-51. [PMID: 15350691 DOI: 10.1016/j.peptides.2004.05.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2004] [Revised: 05/13/2004] [Accepted: 05/13/2004] [Indexed: 12/31/2022]
Abstract
Sarafotoxins (SRTXs) constitute a family of vasoactive peptides that were initially isolated from the venom of Atractaspis engaddensis, and that are structurally and functionally related to endothelins (ETs). Analysis of the venom of Atractaspis microlepidota microlepidota revealed several new SRTX molecules manifesting some new structural and functional characteristics. These novel SRTXs are longer by three amino acids than the previously described SRTXs, and are designated here "long-SRTXs". Six isoforms, derived from new poly-cistronic precursors, have been identified so far in the venom of this snake. One of these isoforms, designated SRTX-m, was chemically synthesized and its biological properties were studied. Our results show that SRTX-m induces toxicity in mice, mostly due to vasoconstriction, and also that it has a lower toxicity and potency than the more potent SRTX described up to now: sarafotoxin-b (SRTX-b) from A. engaddensis.
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Affiliation(s)
- Mirian A F Hayashi
- Biochemical and Biophysical Laboratory, Instituto Butantan, SP 05503-900 Sao Paulo, Brazil
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21
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Hayashi MAF, Murbach AF, Ianzer D, Portaro FCV, Prezoto BC, Fernandes BL, Silveira PF, Silva CA, Pires RS, Britto LRG, Dive V, Camargo ACM. The C-type natriuretic peptide precursor of snake brain contains highly specific inhibitors of the angiotensin-converting enzyme. J Neurochem 2003; 85:969-77. [PMID: 12716428 DOI: 10.1046/j.1471-4159.2003.01743.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The bradykinin-potentiating peptides from Bothrops jararaca venom are the most potent natural inhibitors of the angiotensin-converting enzyme. The biochemical and biological features of these peptides were crucial to demonstrate the pivotal role of the angiotensin-converting enzyme in blood pressure regulation. In the present study, seven bradykinin-potentiating peptides were identified within the C-type natriuretic peptide precursor cloned from snake brain. The bradykinin-potentiating peptides deduced from the B. jararaca brain precursor are strong in vitro inhibitors of the angiotensin-converting enzyme (nanomolar range), and also potentiate the bradykinin effects in ex vivo and in vivo experiments. Two of these peptides are novel bradykinin-potentiating peptides, one of which displays high specificity toward the N-domain active site of the somatic angiotensin-converting enzyme. In situ hybridization studies revealed the presence of the bradykinin-potentiating peptides precursor mRNAs in distinct regions of the B. jararaca brain, such as the ventromedial hypothalamus, the paraventricular nuclei, the paraventricular organ, and the subcommissural organ. The biochemical and pharmacological properties of the brain bradykinin-potentiating peptides, their presence within the neuroendocrine regulator C-type natriuretic peptide precursor, and their expression in regions of the snake brain correlated to neuroendocrine functions, strongly suggest that these peptides belong to a novel class of endogenous vasoactive peptides.
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Affiliation(s)
- Mirian A F Hayashi
- Center for Applied Toxinology--CAT/CEPID, Instituto Butantan, Avenue.Vital Brazil 15600, São Paulo, SP 05530-900, Brazil
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22
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Affiliation(s)
- Frédéric Ducancel
- Département d'Ingénierie et d'Etudes des Protéines, Bt 152, CE de Saclay, 91191, Gif sur Yvette Cedex, France.
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23
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Borgheresi RA, Palma MS, Ducancel F, Camargo AC, Carmona E. Expression and processing of recombinant sarafotoxins precursor in Pichia pastoris. Toxicon 2001; 39:1211-8. [PMID: 11306132 DOI: 10.1016/s0041-0101(00)00265-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Sarafotoxins are peptides isolated from the Atractaspis snake venom, with strong constrictor effect on cardiac and smooth muscle. They are structurally and functionally related to endothelins. The sarafotoxins precursor cDNA predicts an unusual structure 'rosary-type', with 12 successive similar stretches of sarafotoxin (SRTX) and spacer. In the present work, the recombinant precursor of SRTXs was sub-cloned and expressed in the yeast Pichia pastoris, and secreted to the culture medium. Characterization by SDS-PAGE, immunoblot, mass spectrometry and biological activity, suggests that intact precursor was expressed but processing into mature toxins also occurred. Furthermore, our results indicate that the correct proportion of sarafotoxin types as contained in the precursor, is obtained in the yeast culture medium. Contractile effects of the expressed toxins, on rat and Bothrops jararaca isolated aorta, were equivalent to 5x10(-10)M and 5x10(-11)M of sarafotoxin b, respectively. The enzymes responsible for the complete maturation of sarafotoxins precursor are still unknown. Our results strongly suggest that the yeast Pichia pastoris is able to perform such a maturation process. Thus, the yeast Pichia pastoris may offer an alternative to snake venom gland to tentatively identify the molecular process responsible for SRTXs release.
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Affiliation(s)
- R A Borgheresi
- Lab. Farmacologia, Instituto Butantan, Av. Vital Brazil, 1500, 05503-900, São Paulo, Brazil.
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24
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Saida K, Hashimoto M, Mitsui Y, Ishida N, Uchide T. The prepro vasoactive intestinal contractor (VIC)/endothelin-2 gene (EDN2): structure, evolution, production, and embryonic expression. Genomics 2000; 64:51-61. [PMID: 10708518 DOI: 10.1006/geno.1999.6083] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Murine vasoactive intestinal contractor (VIC) and its human analog endothelin-2 (ET2) are potent vasoactive hormones composed of 21 amino acids. To study the structural characteristics of the VIC/ET2 gene (HGMW-approved symbol EDN2), we isolated the full length of the mouse VIC gene. Sequence analysis indicates that a biologically active mature VIC peptide is produced from a 175-residue precursor protein; preproVIC (PPVIC). Several remarkable similarities of the PPVIC gene to the human preproendothelin-1 gene strongly suggest that the two genes have arisen from a common progenitor by gene duplication. Transfection of ACHN adenocarcinoma cells with the cDNA resulted in the production of VIC peptide. VIC production was increased by the deletion of the 3'-untranslated region, which contains an AU-rich mRNA destabilizing sequence. Increased PPVIC gene expression during the late embryonic stage suggests an important function in development. This study provides the basis for disruption and regulation analysis of the gene, which may lead to a better understanding of VIC/ET2's physiological significance.
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Affiliation(s)
- K Saida
- National Institute of Bioscience and Human Technology, Tsukuba, Ibaraki, 305-8566, Japan.
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25
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Higuchi S, Murayama N, Saguchi K, Ohi H, Fujita Y, Camargo AC, Ogawa T, Deshimaru M, Ohno M. Bradykinin-potentiating peptides and C-type natriuretic peptides from snake venom. IMMUNOPHARMACOLOGY 1999; 44:129-35. [PMID: 10604536 DOI: 10.1016/s0162-3109(99)00119-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Cloning of cDNAs encoding bradykinin-potentiating peptides (BPPs)-C-type natriuretic peptide (CNP) precursor or its homologue was performed for cDNA libraries of Bothrops jararaca (South American snake), Trimeresurus flavoviridis, Trimeresurus gramineus and Agkistrodon halys blomhoffi (Asian snakes), all belonging to Crotalinae subfamily. Each cDNA library was constructed from the venom glands of a single snake to preclude ambiguity by intraspecies variation in venom components. Thirteen positive clones derived from B. jararaca were divided into two types depending on restriction sites. Differences in the nucleotide sequence arise at three locations and two of them accompanied amino acid conversions. Despite the differences, both types of cDNA clones encode the BPP-CNP precursor of 256 amino acid residues. Sequence analysis demonstrated that cDNA clones from three Asian snakes encode homologues of the BPP-CNP precursor from B. jararaca. In a precursor polypeptide, a signal sequence (approximately 25 aa) at the N-terminus is followed by sequences of BPP or the analogue (5-13 aa) with flanking spacer sequences (indefinite number of aa), an intervening linker sequence (approximately 144 aa) with unidentified function, and a CNP sequence (22 aa) with a preceding processing signal sequence (10 aa). cDNA clones from A. halys blomhoffi encode two distinct peptides in place of BPP, and T. flavoviridis and T. gramineus were shown to have considerably different sequences in the BPP domain from those known as BPP sequences. The present results provide evidence for a wide distribution of the orthologous gene expressing a series of bioactive peptides among Crotalinae subfamily.
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Affiliation(s)
- S Higuchi
- School of Pharmaceutical Sciences, Showa University, Tokyo, Japan.
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26
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Ducancel F, Wery M, Hayashi MA, Muller BH, Stöcklin R, Ménez A. Les sarafotoxines de venins de serpent. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0924-4204(99)80033-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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27
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Ho PL, Soares MB, Maack T, Gimenez I, Puorto G, Furtado MF, Raw I. Cloning of an unusual natriuretic peptide from the South American coral snake Micrurus corallinus. EUROPEAN JOURNAL OF BIOCHEMISTRY 1997; 250:144-9. [PMID: 9432002 DOI: 10.1111/j.1432-1033.1997.00144.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In the course of cloning abundant cDNAs from the South American coral snake Micrurus corallinus venom gland, we characterized a cDNA coding for a putative natriuretic peptide. All the natural natriuretic peptides described so far, possess a ring structure composed of 17 amino acids formed through an S-S bridge which is extended at the N-terminus by few to several amino acids and may be extended at the C-terminus, usually 4-7 amino acids. In contrast, the M. corallinus natriuretic peptide presents several distinct features: (a) the proform of the deduced natriuretic peptide displays an unusual C-terminus extension. This implies that the mature peptide has a long C-terminal tail or it is further extensively processed to result in the mature natriuretic peptide with the expected 4-7 amino-acid extension. (b) the deduced natriuretic peptide presents an unusual internal Cys within the ring structure. This raises the possibility of natriuretic peptides with a smaller ring structure. (c) the putative natriuretic peptide is flanked by two homologous peptides of unknown function. In addition, an analogous peptide was synthesized and assayed on perfused rat kidney, showing a dose-dependent response in urinary volume and sodium excretion. Moreover, northern-blot studies showed that M. corallinus natriuretic peptide transcripts were highly expressed in venom glands, but they were not detectable in other tissues like heart and brain, suggesting a main role for this M. corallinus natriuretic peptide in the venom gland or in the envenomation by this coral snake's bite.
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Affiliation(s)
- P L Ho
- Centro de Biotecnologia, Instituto Butantan, São Paulo, Brazil
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28
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Murayama N, Hayashi MA, Ohi H, Ferreira LA, Hermann VV, Saito H, Fujita Y, Higuchi S, Fernandes BL, Yamane T, de Camargo AC. Cloning and sequence analysis of a Bothrops jararaca cDNA encoding a precursor of seven bradykinin-potentiating peptides and a C-type natriuretic peptide. Proc Natl Acad Sci U S A 1997; 94:1189-93. [PMID: 9037028 PMCID: PMC19766 DOI: 10.1073/pnas.94.4.1189] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A 1.8-kb cDNA clone was isolated from a Bothrops jararaca venom gland cDNA library that encodes a 256-aa precursor for bradykinin-potentiating peptides (angiotensin-converting enzyme inhibitors) and a C-type natriuretic peptide (CNP). The seven bradykinin-potentiating peptides are aligned tandemly after the hydrophobic signal peptide sequence, followed by a putative intervening sequence and a CNP at the C terminus. Northern blot analysis indicated the predominant expression of a 1.8-kb mRNA in the venom glands as well as in the spleen and the brain. Two lower intensity mRNA bands of 3.5 kb and 5.7 kb also hybridized to the cDNA clone. Radioimmunoassay for the CNP was performed using the antiserum against rat CNP. The presence of CNP immunoreactivity was detected in the low molecular weight fraction of the Bothrops jararaca venom.
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Affiliation(s)
- N Murayama
- School of Pharmaceutical Sciences, Showa University, Shinagawa, Tokyo, Japan
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29
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Nishigaki T, Chiba K, Miki W, Hoshi M. Structure and function of asterosaps, sperm-activating peptides from the jelly coat of starfish eggs. ZYGOTE 1996; 4:237-45. [PMID: 9117284 DOI: 10.1017/s0967199400003154] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Jelly coat of starfish eggs has the capacity to activate homologous spermatozoa and induce the acrosome reaction. We have isolated 12 sperm-activating peptides (SAPs) from the egg jelly of the starfish, Asterias amurensis. Eleven SAPs were structurally identified by sequence analysis and electro-spray ionisation mass spectrometry. All of them are glutamine-rich tetratriacontapeptides with an intramolecular disulphide linkage between Cys8 and Cys32. They are much larger than sea urchin SAPs and do not show any significant sequence similarities to known proteins. Thus we have collectively named them asterosaps. The amino terminal region, where structural diversity of asterosaps is observed, is not important for their activity, whereas the disulphide linkage is essential. Asterosaps do not induce the acrosome reaction by themselves, but are able to induce the acrosome reaction in combination with an egg jelly glycoconjugate named ARIS. Furthermore, anti-asterosap rabbit antibody significantly decreased the acrosome reaction-inducing activity of the jelly solution and the activity was restored by addition of excess asterosap. These results support our hypothesis that the main physiological role of SAPs is the induction of the acrosome reaction in cooperation with two other jelly components, ARIS and Co-ARIS.
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Affiliation(s)
- T Nishigaki
- Department of Life Science, Tokyo Institute of Technology, Osaka, Japan
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30
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Chen N, Upcroft JA, Upcroft P. A Giardia duodenalis gene encoding a protein with multiple repeats of a toxin homologue. Parasitology 1995; 111 ( Pt 4):423-31. [PMID: 11023406 DOI: 10.1017/s0031182000065926] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A gene, CRP136, from the intestinal protozoan parasite Giardia duodenalis, expressed at a high level in a metronidazole-resistant line, encodes a 136 kDa protein with 23 copies of a 40 amino acid repeat. The protein is cysteine-rich and has the typical membrane-spanning region and CXXC amino acid motifs of a family of Giardia cysteine-rich surface proteins (CRSPs). The repeat unit in CRP136, shares 57% homology with the gene encoding the precursor of the sarafotoxins, a group of snake toxins from the burrowing adder known to cause symptoms similar to those of humans acutely infected with Giardia. The sarafotoxins are low molecular weight sulphydryl cross-linked peptides which are proteolytically cleaved from a precursor polyprotein. CRP136 has homology over the entire length of the sarafotoxin precursor, and the repeats are of the same length. Thus CRP136 represents the first evidence for a potential Giardia toxin. The genomic copy number of CRP136 appears to be the same in both the parent and drug-resistant lines and expression of this gene, and at least one other, is associated with a conserved partial duplication, but not amplification, of one chromosome.
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Affiliation(s)
- N Chen
- Queensland Institute of Medical Research, Brisbane, Australia
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31
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Abstract
The endothelins (ETs) are potent vasoactive peptides that appear to be involved in diverse biological actions, for example, contraction, neuromodulation, and neurotransmission, as well as in various pathophysiological conditions, such as renal and heart failure. The diversity of actions of ETs may be explained in terms of (1) the existence of several receptor subtypes and (2) the activation of different signal transduction pathways. This review summarizes the state of the art in this intensively studied field, with particular focus on structural aspects, receptor heterogeneity, coupling of receptors to G-proteins, and signal transduction mechanisms mediated by the activation of ET-receptors.
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Affiliation(s)
- M Sokolovsky
- Laboratory of Neurobiochemistry, Tel Aviv University, Israel
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32
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Lamthanh H, Deprun C, Le Beyec YL. Plasma desorption mass spectrometry of two synthetic sarafotoxins: side reactions and characterization of the intermediates. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 1994; 8:971-975. [PMID: 7696705 DOI: 10.1002/rcm.1290081213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Sarafotoxins (SRTXs) form a family of toxic and potent vasoconstrictor peptides of 21 amino acids and two disulfide bonds. They are present in the venom of the burrowing asp Atractaspis engaddensis. We have made two derivatives of the amino acid sequence of SRTX-b, one of the most potent isotoxins, in the solid phase. First, we replaced Ser2 by Thr, to investigate whether, as previously postulated, this change is responsible for the weak activities of SRTXs c and d. Secondly, we replaced Ser2, Asp18 and Val19 respectively by Thr, Gly and Ile, with a view to generating SRTX-e whose amino acid sequence was deduced from cDNA. Solid-phase peptide synthesis (SPPS) was performed according to the tert-butyloxycarbonyl strategy and the disulfides were paired sequentially using a selective chemistry. The disulfide 1-15 was formed by oxidation of cysteines1,15 with ferricyanide, whereas disulfide 3-11 was made by iodine oxidation of Acm-blocked cysteines3,11. By plasma desorption mass spectrometry (PDMS), we monitored all possible side reactions that occurred during the synthesis. We thus observed a benzyl shift in mass spectra when aspartic and glutamic acid side chains were protected by a benzyl group during the SPPS. This could be circumvented by using instead, a cyclohexyl protecting group. We also noted the oxidation of the methionine and the tryptophan side chain (formation of methionine sulfoxide and oxindole ring of tryptophan) to a small extent during the cleavage peptide/solid phase oxidation of the methionine side chain during the formation of the disulfide 1-15 by ferricyanide.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H Lamthanh
- CEA, Département d'Ingénierie et d'Etudes des Protéines (DIEP), C. E. Saclay, Gif sur Yvette, France
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33
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Lamthanh H, Bdolah A, Wollberg Z, Gy JL. Separation of Two Isoforms (Ser7/Thr7) of Natural Sarafotoxin-a By Capillary Electrophoresis: Mass Spectrometry and Synthesis. ACTA ACUST UNITED AC 1994. [DOI: 10.1080/10826079408016159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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34
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Lamthanh H, Bdolah A, Creminon C, Grassi J, Menez A, Wollberg Z, Kochva E. Biological activities of [Thr2]sarafotoxin-b, a synthetic analogue of sarafotoxin-b. Toxicon 1994; 32:1105-14. [PMID: 7801346 DOI: 10.1016/0041-0101(94)90394-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The 21 amino acid sarafotoxins (SRTX) c and d/e as well as endothelin-3 (ET-3) are known to be less toxic and weaker pharmacologically than the other isopeptides SRTX-a, SRTX-b and ET-1. Since SRTX-c, SRTX-d/e and ET-3 possess a Thr instead of a Ser at position 2, we investigated the possibility that this mutation could be responsible for the observed biological differences. Here we show that the synthetic [Thr2]SRTX-b has indeed a lower vasoconstriction efficacy (approximately 35%) in the rabbit aorta, but it is nearly as potent as SRTX-b in toxicity tests and in influencing contraction of the rat uterus. Using monoclonal antibodies directed against the structurally related endothelin-1, we also show that the antigenicity of the analogue is comparable to that of SRTX-b, suggesting that the overall structure of the two peptides is similar, despite the substitution at position 2. We suggest that the Thr2 substitution contributes to the lower activity of the 'weak' peptides in some systems; however, additional substitutions found in the 'weak' peptides of the ET/SRTX family most probably contribute to their low pharmacological activity.
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Affiliation(s)
- H Lamthanh
- Departement d'Ingenierie, Etudes des Proteines, DSV, CEA, CE, Gif sur Yvette, France
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35
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Warner TD, Battistini B, Doherty AM, Corder R. Endothelin receptor antagonists: actions and rationale for their development. Biochem Pharmacol 1994; 48:625-35. [PMID: 8080434 DOI: 10.1016/0006-2952(94)90038-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- T D Warner
- William Harvey Research Institute, Medical College of St. Bartholomew's Hospital, London, U.K
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