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Paulo Lee Ho - One of the best experts on this subject based on the ideXlab platform.
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some aspects of the venom proteome of the colubridae snake philodryas olfersii revealed from a duvernoy s venom gland transcriptome
FEBS Letters, 2006Co-Authors: Ana T C Ching, Marisa Maria Teixeira Da Rocha, Maria De Fatima D Furtado, Paulo Lee Ho, Solange M T Serrano, Adriana Franco Paes Leme, Daniel C. Pimenta, Inacio L M JunqueiradeazevedoAbstract:We investigated the putative toxins of Philodryas olfersii (Colubridae), a representative of a family of snakes neglected in venom studies despite their growing medical importance. Transcriptomic data of the venom gland complemented by proteomic analysis of the gland secretion revealed the presence of major toxin classes from the Viperidae family, including serine proteases, metalloproteases, C-type lectins, Crisps, and a C-type natriuretic peptide (CNP). Interestingly, the phylogenetic analysis of the CNP precursor showed it as a linker between two related precursors found in Viperidae and Elapidae snakes. We suggest that these precursors constitute a monophyletic group derived from the vertebrate CNPs.
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lachesis muta Viperidae cdnas reveal diverging pit viper molecules and scaffolds typical of cobra elapidae venoms implications for snake toxin repertoire evolution
Genetics, 2006Co-Authors: Inacio L M Junqueiradeazevedo, Ana T C Ching, Paulo Lee Ho, Eneas Carvalho, Fernanda Faria, Milton Y Nishiyama, Marcelo R V DinizAbstract:Efforts to describe toxins from the two major families of venomous snakes (Viperidae and Elapidae) usually reveal proteins belonging to few structural types, particular of each family. Here we carried on an effort to determine uncommon cDNAs that represent possible new toxins from Lachesis muta (Viperidae). In addition to nine classes of typical toxins, atypical molecules never observed in the hundreds of Viperidae snakes studied so far are highly expressed: a diverging C-type lectin that is related to Viperidae toxins but appears to be independently originated; an ohanin-like toxin, which would be the third member of the most recently described class of Elapidae toxins, related to human butyrophilin and B30.2 proteins; and a 3FTx-like toxin, a new member of the widely studied three-finger family of proteins, which includes major Elapidae neurotoxins and CD59 antigen. The presence of these common and uncommon molecules suggests that the repertoire of toxins could be more conserved between families than has been considered, and their features indicate a dynamic process of venom evolution through molecular mechanisms, such as multiple recruitments of important scaffolds and domain exchange between paralogs, always keeping a minimalist nature in most toxin structures in opposition to their nontoxin counterparts.
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molecular cloning and expression of a functional snake venom vascular endothelium growth factor vegf from the bothrops insularis pit viper a new member of the vegf family of proteins
Journal of Biological Chemistry, 2001Co-Authors: I Junqueira L M De Azevedo, S H Farsky, Maria Leonor S Oliveira, Paulo Lee HoAbstract:Abstract During the generation of abundant expressed sequence tags from the Viperidae snake Bothrops insularis venom glands, we identified for the first time a cDNA coding for a putative vascular endothelial growth factor-like (VEGF-like) protein. The deduced primary sequence, after complete sequencing of the longest snake venom VEGF (svVEGF) cDNA, displayed similarity with vertebrate VEGFs and with the hypotensive factor fromVipera aspis venom. Its cDNA was subcloned, expressed in Escherichia coli with a His6 tag as an insoluble monomer, and purified by Ni2+-affinity chromatography after 8 m urea extraction. Antiserum against svVEGF was generated and tested in Western blot against proteins from snake venoms and cellular extracts. The mature svVEGF appears to be ubiquitously distributed throughout snake venoms and was also confirmed by Northern blot studies of other related Viperidae species and by cDNA cloning of svVEGF from Bothrops jararacapit viper. The produced recombinant protein dimerizes after refolding processes and was biologically characterized, showing ability to increase vascular permeability. These results established that svVEGF is a novel and important active toxin during the early stages of bothropic snake bite envenoming and represents a new member of the VEGF family of proteins.
Inacio L M Junqueiradeazevedo - One of the best experts on this subject based on the ideXlab platform.
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some aspects of the venom proteome of the colubridae snake philodryas olfersii revealed from a duvernoy s venom gland transcriptome
FEBS Letters, 2006Co-Authors: Ana T C Ching, Marisa Maria Teixeira Da Rocha, Maria De Fatima D Furtado, Paulo Lee Ho, Solange M T Serrano, Adriana Franco Paes Leme, Daniel C. Pimenta, Inacio L M JunqueiradeazevedoAbstract:We investigated the putative toxins of Philodryas olfersii (Colubridae), a representative of a family of snakes neglected in venom studies despite their growing medical importance. Transcriptomic data of the venom gland complemented by proteomic analysis of the gland secretion revealed the presence of major toxin classes from the Viperidae family, including serine proteases, metalloproteases, C-type lectins, Crisps, and a C-type natriuretic peptide (CNP). Interestingly, the phylogenetic analysis of the CNP precursor showed it as a linker between two related precursors found in Viperidae and Elapidae snakes. We suggest that these precursors constitute a monophyletic group derived from the vertebrate CNPs.
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lachesis muta Viperidae cdnas reveal diverging pit viper molecules and scaffolds typical of cobra elapidae venoms implications for snake toxin repertoire evolution
Genetics, 2006Co-Authors: Inacio L M Junqueiradeazevedo, Ana T C Ching, Paulo Lee Ho, Eneas Carvalho, Fernanda Faria, Milton Y Nishiyama, Marcelo R V DinizAbstract:Efforts to describe toxins from the two major families of venomous snakes (Viperidae and Elapidae) usually reveal proteins belonging to few structural types, particular of each family. Here we carried on an effort to determine uncommon cDNAs that represent possible new toxins from Lachesis muta (Viperidae). In addition to nine classes of typical toxins, atypical molecules never observed in the hundreds of Viperidae snakes studied so far are highly expressed: a diverging C-type lectin that is related to Viperidae toxins but appears to be independently originated; an ohanin-like toxin, which would be the third member of the most recently described class of Elapidae toxins, related to human butyrophilin and B30.2 proteins; and a 3FTx-like toxin, a new member of the widely studied three-finger family of proteins, which includes major Elapidae neurotoxins and CD59 antigen. The presence of these common and uncommon molecules suggests that the repertoire of toxins could be more conserved between families than has been considered, and their features indicate a dynamic process of venom evolution through molecular mechanisms, such as multiple recruitments of important scaffolds and domain exchange between paralogs, always keeping a minimalist nature in most toxin structures in opposition to their nontoxin counterparts.
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a survey of gene expression and diversity in the venom glands of the pitviper snake bothrops insularis through the generation of expressed sequence tags ests
Gene, 2002Co-Authors: Inacio L M JunqueiradeazevedoAbstract:In order to produce a global panorama of the transcriptional activity of snake venom glands and to correlate with its venom composition, we constructed a DNA complementary to RNA library from the venom glands of the Viperidae snake Bothrops insularis for the generation of expressed sequence tags (ESTs). Sequences from 610 independent clones were grouped in 297 clusters, revealing the putative identification of 210 distinct gene products. Toxin sequences correspond to 56% of all transcripts (85 clusters), being the metalloproteinases (23%) and the bradykinin-potentiating peptides (11%) the major components. This approach revealed a new highly expressed toxin similar to vascular endothelial growth factor, which was recently reported (J. Biol. Chem. 276 (2001) 39836). Among the 125 clusters matching cellular proteins, the major part represents molecules involved in gene and protein expression, notably in disulfide bond assembly, reflecting a high specialization of this tissue for toxin synthesis. An unusual representation of retrotransposon-like sequences was also found and could be related to the occurrence and diversity of many paralogous forms of toxins in the venom gland. Our B. insularis dbEST allowed the identification of the most common classes of toxins present in Viperidae venoms, which parallels the complex hemorrhagic effects evoked by the venom on the prey. In addition, it provides the first comprehensive set of reptilian gene sequences described so far.
Ana T C Ching - One of the best experts on this subject based on the ideXlab platform.
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some aspects of the venom proteome of the colubridae snake philodryas olfersii revealed from a duvernoy s venom gland transcriptome
FEBS Letters, 2006Co-Authors: Ana T C Ching, Marisa Maria Teixeira Da Rocha, Maria De Fatima D Furtado, Paulo Lee Ho, Solange M T Serrano, Adriana Franco Paes Leme, Daniel C. Pimenta, Inacio L M JunqueiradeazevedoAbstract:We investigated the putative toxins of Philodryas olfersii (Colubridae), a representative of a family of snakes neglected in venom studies despite their growing medical importance. Transcriptomic data of the venom gland complemented by proteomic analysis of the gland secretion revealed the presence of major toxin classes from the Viperidae family, including serine proteases, metalloproteases, C-type lectins, Crisps, and a C-type natriuretic peptide (CNP). Interestingly, the phylogenetic analysis of the CNP precursor showed it as a linker between two related precursors found in Viperidae and Elapidae snakes. We suggest that these precursors constitute a monophyletic group derived from the vertebrate CNPs.
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lachesis muta Viperidae cdnas reveal diverging pit viper molecules and scaffolds typical of cobra elapidae venoms implications for snake toxin repertoire evolution
Genetics, 2006Co-Authors: Inacio L M Junqueiradeazevedo, Ana T C Ching, Paulo Lee Ho, Eneas Carvalho, Fernanda Faria, Milton Y Nishiyama, Marcelo R V DinizAbstract:Efforts to describe toxins from the two major families of venomous snakes (Viperidae and Elapidae) usually reveal proteins belonging to few structural types, particular of each family. Here we carried on an effort to determine uncommon cDNAs that represent possible new toxins from Lachesis muta (Viperidae). In addition to nine classes of typical toxins, atypical molecules never observed in the hundreds of Viperidae snakes studied so far are highly expressed: a diverging C-type lectin that is related to Viperidae toxins but appears to be independently originated; an ohanin-like toxin, which would be the third member of the most recently described class of Elapidae toxins, related to human butyrophilin and B30.2 proteins; and a 3FTx-like toxin, a new member of the widely studied three-finger family of proteins, which includes major Elapidae neurotoxins and CD59 antigen. The presence of these common and uncommon molecules suggests that the repertoire of toxins could be more conserved between families than has been considered, and their features indicate a dynamic process of venom evolution through molecular mechanisms, such as multiple recruitments of important scaffolds and domain exchange between paralogs, always keeping a minimalist nature in most toxin structures in opposition to their nontoxin counterparts.
Jose Maria Gutierrez - One of the best experts on this subject based on the ideXlab platform.
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comparative study of the cytolytic activity of myotoxic phospholipases a2 on mouse endothelial tend and skeletal muscle c2c12 cells in vitro
Toxicon, 1999Co-Authors: Yamileth Angulo, Bruno Lomonte, Motonori Ohno, Stefano Rufini, Wonhwa Cho, Jose R Giglio, Jose J Daniele, Patricia Geoghegan, Jose Maria GutierrezAbstract:A rapid in vitro cytolytic effect of some myotoxic phospholipases A2 (PLA2s) isolated from the venoms of Viperidae snakes has been previously described. This study was undertaken to investigate if cytolytic activity is a common property of the myotoxic proteins from this group. Murine endothelial cells (tEnd) and skeletal muscle myotubes (C2C12) were utilized as targets. The release of lactic dehydrogenase was quantified as a measure of cell damage, 3 h after exposure of cells to the different PLA2s, including representatives from the genera Bothrops, Agkistrodon, Trimeresurus, Crotalus (family Viperidae), and Notechis (family Elapidae). All of the group II myotoxic PLA2s tested displayed rapid cytolytic activity when tested in the micromolar range of concentrations (8-32 microM). In contrast, the group I myotoxic PLA2 notexin was devoid of this activity. Aspartate-49 and lysine-49 PLA2 group II variants showed a comparable cytolytic effect. Skeletal muscle myotubes, obtained after fusion and differentiation of C2C12 myoblasts, were significantly more susceptible to the cytolytic action of myotoxins than endothelial cells, previously reported to be more susceptible than undifferentiated myoblasts under the same assay conditions. Cytolytic activity appears to be a common characteristic of group II myotoxic PLA2s of the Viperidae. Bee venom PLA2, a group III enzyme of known myotoxicity, also displayed cytotoxic activity on C2C12 myotubes, being devoid of activity on endothelial cells. These results suggest that in vitro differentiated skeletal muscle myotubes may represent a suitable model target for the study of myotoxic PLA2s of the structural group II found in snake venoms.
Jeongchil Yoo - One of the best experts on this subject based on the ideXlab platform.
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First observation on courtship behavior of short-tailed viper snake, Gloydius saxatilis (Squamata: Viperidae) in Korea
Elsevier, 2017Co-Authors: Ki-baek Nam, Jeongchil YooAbstract:Most reptile species have their own mating patterns. Therefore, courtship behaviors are important factors in understanding taxonomic features and species-specific breeding habits in the genus. This study explores the mating behaviors of the short-tailed viper snake (Gloydius saxatilis) which has never been reported. From September 2012 to August 2013, we observed the courtship behaviors of short-tailed viper snakes in Chunma Mountain County Park, Namyangju City, Gyeonggi Province, South Korea. In this study, 10 courtship behaviors from three snake couples were considered and compared. The results showed that, in general, most courtship behaviors of G. saxatilis were similar to those of other species of the family Viperidae. However, the most remarkable behavior of female short-tailed viper snakes was âquivering,â which had not yet been reported in females from the other species of the family Viperidae. These results can provide valuable information for research in systematics of short-tailed viper snakes. Keywords: behavior ecology, first report, Gloydius saxatilis, mating behavior, Viperida
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effect of weight of radio transmitters on survival of red tongue viper snake gloydius ussuriensis and short tailed viper snake gloydius saxatilis in the radio transmitter implantation
Journal of Wetlands Research, 2014Co-Authors: Jaehan Shim, Youngmin Choi, Jeongchil YooAbstract:Department of Biology, Kyung Hee University* Korean Herpetofauna Ecological Research Institute** Woo Sung Animal Medical Center요 약한국에 서식하는 뱀목(Squamata) 중 살모사과(Viperidae)에 속하는 쇠살모사(Gloydius ussuriensis)와 까치살모사(Gloydius saxatilis)를 대상으로 무선추적기법을 이용한 행동권 연구를 수행하기 위해 모든 개체에게 체중 대비 5% 이내의 발신기를 삽입하였다. 쇠살모사 5개체, 까치살모사 6개체 총 11개체를 대상으로 발신기 삽입수술을 시행한 결과 쇠살모사의 경우 체중 대비 발신기 무게 비율은 평균 4.2%였으며, 까치살모사의 경우 평균 2.2%였다. 발신기삽입 후 회복기간 동안 까치살모사는 모두 생존한 반면 쇠살모사는 전체 5개체 중 4개체가 생존하지 못해 생존율이 20% 밖에 되질 않았다. 이전의 선행 연구들에서는 체중 대비 발신기 무게 비율을 1-7%까지 다양하게 권고하고 있지만, 이번 연구결과는 쇠사모사와 까치살모사의 행동생태 연구에서 이용되는 몸무게에 대한 발신기 무게 비율은 최소 3.6% 이내로 정해야 안전하다는 것을 보여준다. 핵심용어 : 무선추적기법, 발신기, 까치살모사, 쇠살모사AbstractIn order to study the home range of the red-tongue viper snake (Gloydis ussuriensis) and the short-tailed viper snake (Gloydius saxatilis) belonging to the Viperidae of squamat in Korea, we implanted radio-transmitters which were weighed less than 5% of individual mass in them and traced their location by radio-tracking. Surgeries for transmitter insertion were performed on 5 red-tongue viper snakes and 6 short-tailed viper snakes (total 11 individuals) and the average ratio of transmitter mass to body mass were 4.2% and 2.2%, respectively. After radio-transmitter implantation, all short-tailed viper snakes survived but 4 out of 5 red-tongue viper snakes did not survive during the convalescence stage, showing only 20% of survival rate. The results suggest that the ratio of transmitter mass to body mass should be less than 3.6% at least in these species, although previous studies have recommended various ranges from 1% to 7% as the acceptable ratios.Keywords : Radio-tracking, Radio-transmitter, Short-tailed viper snake, Red-tongue viper snake+ Corresponding author : jcyoo@khu.ac.kr