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Robert W Murphy - One of the best experts on this subject based on the ideXlab platform.
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molecular phylogeography of white lipped tree viper Trimeresurus viperidae
Zoologica Scripta, 2016Co-Authors: Liang Zhang, Xin Chen, Robert W MurphyAbstract:The white-lipped tree viper (Trimeresurus albolabris) is one of the most common venomous snakes with medicine importance in South East Asia. To explore the genetic diversity, population structure and evolutionary history of Trimeresurus albolabris, we collected 98 samples from 27 localities covering its entire distribution. Two mitochondrial gene fragments (cyt-b and ND-4) and two nuclear genes (RAG-1 and NT-3) were sequenced and analysed. Bayesian inference and maximum-likelihood methods were employed to reconstruct the phylogenetic relationships among populations based on the two mitochondrial fragments, and the median-joining networks were depicted using nuclear genes. Divergence date and ancestral area were estimated, and the population demographic history was inferred. Both phylogenetic analyses consistently uncovered that Trimeresurus albolabris was monophyletics, with five geographically structured lineages. Divergence date and ancestral area estimation indicated that T. albolabris originated in northern Thailand and eastern Myanmar at c. 7.15 Ma. Population dynamics analyses showed the southern China lineage has experienced population expansion and contraction, but the others have not. Both the interglacial expansion and the highly heterogeneous habitats resulting from the uplift of the Plateau played a joint role in shaping the present distribution and population structure. The evolutionary history of T. albolabris can be explained by a pattern of two direction dispersal: first from North to South, and then from West to East.
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Molecular phylogeography of white‐lipped tree viper (Trimeresurus; Viperidae)
Zoologica Scripta, 2016Co-Authors: Liang Zhang, Xin Chen, Robert W MurphyAbstract:The white-lipped tree viper (Trimeresurus albolabris) is one of the most common venomous snakes with medicine importance in South East Asia. To explore the genetic diversity, population structure and evolutionary history of Trimeresurus albolabris, we collected 98 samples from 27 localities covering its entire distribution. Two mitochondrial gene fragments (cyt-b and ND-4) and two nuclear genes (RAG-1 and NT-3) were sequenced and analysed. Bayesian inference and maximum-likelihood methods were employed to reconstruct the phylogenetic relationships among populations based on the two mitochondrial fragments, and the median-joining networks were depicted using nuclear genes. Divergence date and ancestral area were estimated, and the population demographic history was inferred. Both phylogenetic analyses consistently uncovered that Trimeresurus albolabris was monophyletics, with five geographically structured lineages. Divergence date and ancestral area estimation indicated that T. albolabris originated in northern Thailand and eastern Myanmar at c. 7.15 Ma. Population dynamics analyses showed the southern China lineage has experienced population expansion and contraction, but the others have not. Both the interglacial expansion and the highly heterogeneous habitats resulting from the uplift of the Plateau played a joint role in shaping the present distribution and population structure. The evolutionary history of T. albolabris can be explained by a pattern of two direction dispersal: first from North to South, and then from West to East.
Motonori Ohno - One of the best experts on this subject based on the ideXlab platform.
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Purification and characterization of L-amino acid oxidase from the venom of Trimeresurus mucrosquamatus (Taiwan habu snake)
Toxicon, 2002Co-Authors: Masayuki Ueda, Chun-chang Chang, Motonori OhnoAbstract:Abstract Purification and characterization of L -amino acid oxidase from the venom of Trimeresurus mucrosquamatus (Taiwan habu snake). Toxicon26, 695 – 706, 1988. — L -Amino acid oxidase (EC. 1.4.3.2) was purified to homogeneity via four steps consisting of Sephadex G-100, CM-Toyopearl 650M, and first and second granulated hydroxyapatite column chromatographies. The mol. wt of the enzyme was 140,000 when estimated by analytical gel filtration and was 70,000 by sodium dodecyl sulfate - polyacrylamide gel electrophoresis, suggesting that the enzyme is composed of two identical subunits. The enzyme has an absorption spectrum characteristic of flavoprotein, contains 2 moles of FMN per mole of enzyme and has an isoelectric point of 5.4. The enzyme oxidatively deaminated hydrophobic amino acids such as Leu, Met, Phe, and Tyr while basic amino acids except for Lys were also oxidized though at slower rates. This specificity was generally similar, with some exceptions, to that of the enzyme from Trimeresurus flavoviridis venom. For oxidative deamination of Leu, Km and maximum velocity of the enzyme were 1.17 mM and 9.9 units/mg, respectively, at pH 7.6. The activity was inhibited almost completely by heavy metal ions, some aromatic benzoates and sulfhydryl reagents but not by metal-chelating agents.
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structures of genes encoding tata binding proteins from Trimeresurus gramineus and t flavoviridis snakes
Gene, 1995Co-Authors: Kinichi Nakashima, Ikuo Nobuhisa, Masanobu Deshimaru, Tomohisa Ogawa, Yasuyuki Shimohigashi, Yasuyuki Fukumaki, Masahira Hattori, Yoshiyuki Sakaki, Shosaku Hattori, Motonori OhnoAbstract:Abstract A cDNA encoding the Trimeresurus gramineus (Tg ; green habu snake) TATA-☐-binding protein (TgTBP) was cloned and sequenced. The cDNA encodes a 33-kDa protein with an extensive sequence similarity to those derived from other organisms, except for the N-terminal domain. Genes encoding TgTBP and Trimeresurus flavoviridis (Tf ; habu snake) TBP (TgTBP) were isolated using a TgTBP cDNA and their nt sequences were determined. They are the first TBP genes entirely sequenced in higher animals. Both genes span over 15 kb and are constructed from eight exons and seven introns. Comparison of the loci of introns on the aligned amino-acid sequences of TBP from six organisms ( Tg, Tf , mouse, Arabidopsis thaliana, Schizosaccharomyces pombe and Acanthamoeba castellanii ) indicated that there are three highly conserved loci in the C-terminal domain.
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Structures of genes encoding TATA ☐-binding proteins from Trimeresurus gramineus and t. flavoviridis snakes
Gene, 1995Co-Authors: Kinichi Nakashima, Ikuo Nobuhisa, Masanobu Deshimaru, Tomohisa Ogawa, Yasuyuki Shimohigashi, Yasuyuki Fukumaki, Masahira Hattori, Yoshiyuki Sakaki, Shosaku Hattori, Motonori OhnoAbstract:Abstract A cDNA encoding the Trimeresurus gramineus (Tg ; green habu snake) TATA-☐-binding protein (TgTBP) was cloned and sequenced. The cDNA encodes a 33-kDa protein with an extensive sequence similarity to those derived from other organisms, except for the N-terminal domain. Genes encoding TgTBP and Trimeresurus flavoviridis (Tf ; habu snake) TBP (TgTBP) were isolated using a TgTBP cDNA and their nt sequences were determined. They are the first TBP genes entirely sequenced in higher animals. Both genes span over 15 kb and are constructed from eight exons and seven introns. Comparison of the loci of introns on the aligned amino-acid sequences of TBP from six organisms ( Tg, Tf , mouse, Arabidopsis thaliana, Schizosaccharomyces pombe and Acanthamoeba castellanii ) indicated that there are three highly conserved loci in the C-terminal domain.
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Polymorphisms of Trimeresurus flavoviridis venom gland phospholipase A2 isozyme genes
Bioscience Biotechnology and Biochemistry, 1994Co-Authors: Kinichi Nakashima, Hiroshi Kihara, Ikuo Nobuhisa, Tomohisa Ogawa, Masahira Hattori, Yoshiyuki Sakaki, Motonori OhnoAbstract:Trimeresurus flavoviridis venom gland phospholipase A2 (PLA2) genes pgPLA 1a and pgPLA 2a encode Asp-49-PLA2 and genes pgPLA lb and pgPLA 2b encode an isozyme of Asp-49-PLA2. Polymorphisms were found in pairs of pgPLA la and pgPLA 2a and of pgPLA lb and pgPLA 2b for individuals of T. flavoviridis. The occurrence of both homozygotes and heterozygotes was demonstrated.
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Characterization of Peptides Isolated from Trimeresurus flavoviridis and Trimeresurus okinavensis Venoms
Bulletin of the Chemical Society of Japan, 1993Co-Authors: Iori Maeda, Hiroshi Kihara, Tamaki Kato, Ayako Tani, Haruhiko Aoyagi, Motonori OhnoAbstract:Three peptides were isolated from both Trimeresurus flavoviridis (Habu snake) and T. okinavensis (Himehabu snake) venoms. Their structures were determined to be pGlu–Lys–Trp, pGlu–Asn–Trp, and pGlu–Gln–Trp. Only pGlu–Lys–Trp showed weak inhibitory activities against angiotensin converting enzyme and H2-protease.
Ponlapat Rojnuckarin - One of the best experts on this subject based on the ideXlab platform.
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molecular cloning of albolatin a novel snake venom metalloprotease from green pit viper Trimeresurus albolabris and expression of its disintegrin domain
Toxicon, 2007Co-Authors: Pon Singhamatr, Ponlapat RojnuckarinAbstract:Abstract Disintegrins are snake venom-derived, RGD- or KGD-containing peptides that can inhibit integrin-mediated platelet aggregation and cell–matix interactions. The aim of this study is to analyze the full-length cDNA sequence of a snake venom metalloprotease (SVMP) from green pit viper (Trimeresurus albolabris) venom and characterize functions of its disintegrin domain on human platelets. From the primary cDNA library of venom glands, a partial sequence of a novel SVMP (Albolatin) was obtained. Using the 5′-RACE, the 2040 bp full-length sequence of albolatin mRNA was derived. The deduced amino acid sequence revealed a type P-II SVMP of 484 amino acid residues comprising a signal region, pro-peptide, inactive metalloprotease domain and a disintegrin domain. It showed 85% amino acid identical to Trimeresurus jerdonii jerdonitin and 81% to Gloydius halys agkistin. Sequence alignment revealed that all cysteines were conserved except for an extra cysteine in the protease domain of albolatin. The disintegrin domain of albolatin, which comprised 76 amino acids with a KGDW sequence, was expressed in Pichia pastoris with the yield of 3.3 mg/L of culture medium. The molecular weights were 11 kDa in reduced and 22 kDa in non-reduced states indicating a homodimer. It can inhibit collagen-induced platelet aggregation with IC50 of 976 nM and, therefore, should be investigated for a potential to be a novel therapeutic agent.
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molecular cloning of novel serine proteases and phospholipases a2 from green pit viper Trimeresurus albolabris venom gland cdna library
Toxicon, 2006Co-Authors: Ponlapat Rojnuckarin, Chuanchom Muanpasitporn, Lawan Chanhome, Jaradpong Arpijuntarangkoon, Tanin IntragumtornchaiAbstract:Green pit viper (Trimeresurus albolabris) is the most common venomous snake responsible for bites in Bangkok. It causes local edema and systemic hypofibrinogenemia resulted from the thrombin-like, as well as the fibrinolytic effects of the venom. However, the amino acid sequences of these venom proteins have never been reported. In this study, we have cloned five novel serine proteases from the Thai T. albolabris venom gland cDNA library. They were all closely homologous to the corresponding serine proteases from Chinese green viper (Trimeresurus stejnegeri), suggesting the evolutionary proximity of the two species. In addition, their functional activities could be deduced. There were predicted to be two thrombin-like enzymes (GPV-TL1 and GPV-TL-2), two isoforms of a fibrinogenolytic enzyme (albofibrase) and a plasminogen activator (GPV-PA), suggesting that defibrination syndrome in patients is a combination of these enzymatic effects. By multiple sequence alignment, no conserved residue or motif responsible for distinct functions of snake venom serine proteases could be observed. Moreover, one Lys 49 and one Asn 49 phospholipase A2 (PLA2) genes were cloned. Lys 49 PLA2 was predicted to devoid of catalytic activity, but showed a carboxy terminal cytotoxic region. No Asp 49 PLA2 was found in 150 clones screened. This explains the marked limb edema but no hemolysis in patients. These novel serine proteases have potentials to be therapeutic anti-thrombotic and thrombolytic agents in the future. q 2005 Elsevier Ltd. All rights reserved.
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the effects of green pit viper Trimeresurus albolabris and Trimeresurus macrops venom on the fibrinolytic system in human
Toxicon, 1999Co-Authors: Ponlapat Rojnuckarin, Narumol Pakmanee, Tanin Intragumtornchai, Rung Sattapiboon, Chuanchom Muanpasitporn, Orawan Khow, Daratana SwasdikulAbstract:Abstract Green pit viper ( Trimeresurus albolabris and Trimeresurus macrops ) venom was found to have a thrombin-like effect in vitro but cause a defibrination syndrome in vivo. The effects of venom on fibrinolytic system have not been well characterized. This knowledge can help to define the roles of antifibrinolytic therapy, give insights in fibrinolytic system regulation and potentially lead to identification of a new profibrinolytic agent from this venom. Forty-six cases of green pit viper bites were studied for various coagulation and fibrinolytic parameters and correlated with serum venom levels measured by ELISA. Fibrinolytic system activation is very common as indicated by low plasminogen (50%), low antiplasmin (56.5%) and elevated fibrin–fibrinogen degradation products (FDPs, 97.4%) levels. FDP test is very sensitive and a normal level is useful for exclusion of systemic envenomation. In contrast to some other models of defibrination syndrome, such as Russell viper ( Daboia russelli siamensis ), elevation of plasminogen activator activity (PA) was found indicating a hyperfibrinolytic state. Definite increase in tissue-type plasminogen activator (t-PA) antigen ( p =0.00075) with a modest elevation of its inhibitor plasminogen activator inhibitor-1 (PAI-1) ( p =0.27) probably contributes to this effect. This supports the idea that the balance between plasminogen activators and inhibitors can determine fibrinolytic responses in pathologic states. Fibrinopeptide A levels were markedly elevated (68.43±51.57 ng/ml in cases and 2.83±3.80 ng/ml in control, p
Innho Tsai - One of the best experts on this subject based on the ideXlab platform.
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unusual venom phospholipases a2 of two primitive tree vipers Trimeresurus puniceus and Trimeresurus borneensis
FEBS Journal, 2005Co-Authors: Yingming Wang, Haofan Peng, Innho TsaiAbstract:To explore the venom diversity of Asian pit vipers, we investigated the structure and function of venom phospholipase A2 (PLA2) derived from two primitive tree vipers Trimeresurus puniceus and Trimeresurus borneensis. We purified six novel PLA2s from T. puniceus venom and another three from T. borneensis venom. All cDNAs encoding these PLA2s except one were cloned, and the molecular masses and N-terminal sequences of the purified enzymes closely matched those predicted from the cDNA. Three contain K49 and lack a disulfide bond at C61–C91, in contrast with the D49-containing PLA2s in both venom species. They are less thermally stable than other K49-PLA2s which contain seven disulfide bonds, as indicated by a decrease of 8.8 � C in the melting temperature measured by CD spectroscopy. The M110D mutation in one of the K49-PLA2s apparently reduced its edematous potency. A phylogenetic tree based on the aminoacid sequences of 17 K49-PLA2s from Asian pit viper venoms illustrates close relationships among the Trimeresurus species and intergeneric segregations. Basic D49-PLA2s with a unique Gly6 substitution were also purified from both venoms. They showed edema-inducing and anticoagulating activities. It is notable that acidic PLA2s from both venoms inhibited blood coagulation rather than platelet aggregation, and this inhibition was only partially dependent on enzyme activity. These results contribute to our understanding of the evolution of Trimeresurus pit vipers and the structure–function relationships between various subtypes of crotalid venom PLA2.
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Purification, sequencing, and phylogenetic analyses of novel Lys-49 phospholipases A2 from the venoms of rattlesnakes and other pit vipers
Archives of Biochemistry and Biophysics, 2001Co-Authors: Innho Tsai, Yingming Wang, Yi-hsuan Chen, Ming-chang Tu, Anthony T. TuAbstract:Abstract Basic phospholipase A2 homologs with Lys49 substitution at the essential Ca2+-binding site are present in the venom of pit vipers under many genera. However, they have not been found in rattlesnake venoms before. We have now screened for this protein in the venom of rattlesnakes and other less studied pit vipers. By gel filtration chromatography and RP-HPLC, Lys49-phospholipase-like proteins were purified from the venoms of two rattlers, Crotalus atrox and Crotalus m. molossus, and five nonrattlers, Porthidium nummifer, Porthidium godmani, Bothriechis schlegelii, Trimeresurus puniceus, and Trimeresurus albolabris. Their N-terminal amino acid sequences were shown to be characteristic for this phospholipase subfamily. The purified basic proteins from rattlesnakes caused myonecrosis and edema in experimental animals. We have also cloned the cDNAs and solved the complete sequences of four novel Lys49-phospholipases from the venom glands of C. atrox, P. godmani, B. schlegelii, and Deinagkistrodon acutus (hundred-pace). Phylogenetic analyses based on the amino acid sequences of 28 Lys49-phospholipases separate the pitviper of the New World from those of the Old World, and the arboreal Asiatic species from the terrestrial Asiatic species. The implications of the phylogeny tree to the systematics of pit vipers, and structure–function relationship of the Lys49-phospholipases are discussed.
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characterization of a cdna encoding the precursor of platelet aggregation inhibitor and metallproteinase from Trimeresurus mucrosquamatus venom
Biochimica et Biophysica Acta, 1994Co-Authors: Innho Tsai, Yingming WangAbstract:Abstract This paper presents the nucleotide sequence of a cDNA encoding a full-lenght precursor of a novel platelet aggregation inhibitor named trimucrin and a hemorrhagic metalloproteinase from Trimeresurus mucrosquamatus snake venom. The deduced structure of the precursor protein is compared with those of other members of the metalloproteinase/disintegrin family.
Liang Zhang - One of the best experts on this subject based on the ideXlab platform.
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molecular phylogeography of white lipped tree viper Trimeresurus viperidae
Zoologica Scripta, 2016Co-Authors: Liang Zhang, Xin Chen, Robert W MurphyAbstract:The white-lipped tree viper (Trimeresurus albolabris) is one of the most common venomous snakes with medicine importance in South East Asia. To explore the genetic diversity, population structure and evolutionary history of Trimeresurus albolabris, we collected 98 samples from 27 localities covering its entire distribution. Two mitochondrial gene fragments (cyt-b and ND-4) and two nuclear genes (RAG-1 and NT-3) were sequenced and analysed. Bayesian inference and maximum-likelihood methods were employed to reconstruct the phylogenetic relationships among populations based on the two mitochondrial fragments, and the median-joining networks were depicted using nuclear genes. Divergence date and ancestral area were estimated, and the population demographic history was inferred. Both phylogenetic analyses consistently uncovered that Trimeresurus albolabris was monophyletics, with five geographically structured lineages. Divergence date and ancestral area estimation indicated that T. albolabris originated in northern Thailand and eastern Myanmar at c. 7.15 Ma. Population dynamics analyses showed the southern China lineage has experienced population expansion and contraction, but the others have not. Both the interglacial expansion and the highly heterogeneous habitats resulting from the uplift of the Plateau played a joint role in shaping the present distribution and population structure. The evolutionary history of T. albolabris can be explained by a pattern of two direction dispersal: first from North to South, and then from West to East.
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Molecular phylogeography of white‐lipped tree viper (Trimeresurus; Viperidae)
Zoologica Scripta, 2016Co-Authors: Liang Zhang, Xin Chen, Robert W MurphyAbstract:The white-lipped tree viper (Trimeresurus albolabris) is one of the most common venomous snakes with medicine importance in South East Asia. To explore the genetic diversity, population structure and evolutionary history of Trimeresurus albolabris, we collected 98 samples from 27 localities covering its entire distribution. Two mitochondrial gene fragments (cyt-b and ND-4) and two nuclear genes (RAG-1 and NT-3) were sequenced and analysed. Bayesian inference and maximum-likelihood methods were employed to reconstruct the phylogenetic relationships among populations based on the two mitochondrial fragments, and the median-joining networks were depicted using nuclear genes. Divergence date and ancestral area were estimated, and the population demographic history was inferred. Both phylogenetic analyses consistently uncovered that Trimeresurus albolabris was monophyletics, with five geographically structured lineages. Divergence date and ancestral area estimation indicated that T. albolabris originated in northern Thailand and eastern Myanmar at c. 7.15 Ma. Population dynamics analyses showed the southern China lineage has experienced population expansion and contraction, but the others have not. Both the interglacial expansion and the highly heterogeneous habitats resulting from the uplift of the Plateau played a joint role in shaping the present distribution and population structure. The evolutionary history of T. albolabris can be explained by a pattern of two direction dispersal: first from North to South, and then from West to East.
