The Experts below are selected from a list of 51 Experts worldwide ranked by ideXlab platform
Humberto J. Debat - One of the best experts on this subject based on the ideXlab platform.
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Complete genome sequence of a divergent strain of Tibetan frog hepatitis B virus associated with a concave-eared torrent frog (Odorrana tormota)
Archives of Virology, 2019Co-Authors: Humberto J. DebatAbstract:Viruses of the family Hepadnaviridae are characterized by partially dsDNA circular genomes of approximately 3.2 kb, which are reverse transcribed from RNA intermediates. Hepadnaviruses have a broad host range, which includes humans (hepatitis B virus), other mammals (genus Orthohepadnavirus ), and birds (genus Avihepadnavirus ). The known host specificity of hepadnaviruses has been expanded by reports of new viruses infecting fish, amphibians, and reptiles. Tibetan frog hepatitis B virus (TFHBV) was recently discovered in a member of the species Nanorana parkeri (family Dicroglossidae) from Tibet. To increase our understanding of hepadnaviruses that infect amphibian hosts, we identified the full-length genome of a divergent strain, TFHBV-Ot, associated with a concave-eared torrent frog ( Odorrana tormota , family Ranidae) from China by searching deep-sequencing data. TFHBV-Ot shared a genomic organization and 76.6% overall genome sequence nucleotide identity with the prototype TFHBV associated with N. parkeri (TFHBV-Np). The pairwise amino acid sequence identity between the predicted gene products of TFHBV-Ot and TFHBV-Np ranged between 63.9% and 77.9%. Multiple tissue/organ-specific RNAseq datasets suggested a broad tropism of TFHBV, including muscle, gonads and brain. In addition, we provide information about putative virus-derived small RNAs from an amphibian hepadnavirus. The results presented here expand the known genetic diversity and host range of TFHBV to Ranidae frogs, and warrant an investigation of hepadnaviral infection of amphibian brains.
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Complete genome sequence of a divergent strain of Tibetan frog hepatitis B virus associated to concave-eared torrent frog Odorrana tormota
2018Co-Authors: Humberto J. DebatAbstract:The family Hepadnaviridae is characterized by partially dsDNA circular viruses of approximately 3.2 kb, which are reverse transcribed from RNA intermediates. Hepadnaviruses (HBVs) have a broad host range which includes humans (Hepatitis B virus), other mammals (genus Orthohepadnavirus), and birds (Avihepadnavirus). HBVs host specificity has been expanded by reports of new viruses infecting fish, amphibians, and reptiles. The tibetan frog hepatitis B virus (TFHBV) was recently discovered in Nanorana parkeri (Family Dicroglossidae) from Tibet. To increase understanding of hepadnavirus in amphibian host, we identified the full-length genome of a divergent strain TFHBV-Ot associated to the concave-eared torrent frog Odorrana tormota (Family Ranidae) from China by searching deep sequencing data. TFHBV-Ot shared the genomic organization and a 76.6% overall genome nucleotide identity to the prototype TFHBV associated to N. parkeri (TFHBV-Np). TFHBV-Ot amino acid pairwise identity with TFHBV-Np predicted gene products ranged between 63.9% and 77.9%. Multiple tissue/organ specific RNAseq datasets suggest a broad tropism of TFHBV including muscles, gonads and brains. In addition, we provide for the first time evidence of virus derived small RNA from an amphibian hepadnavirus, tentatively enriched in 19-20 nt species and cytidine as first base. The results presented here expand the genetic diversity and the host range of TFHBV to Ranidae frogs, and warrant investigation on hepadnaviral infection of amphibian brains.
Fei Fan Ng Terry - One of the best experts on this subject based on the ideXlab platform.
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Complete genome sequence of a divergent strain of Tibetan frog hepatitis B virus associated with a concave‑eared torrent frog (Odorrana tormota)
'Springer Science and Business Media LLC', 2019Co-Authors: Debat, Humberto Julio, Fei Fan Ng TerryAbstract:Viruses of the family Hepadnaviridae are characterized by partially dsDNA circular genomes of approximately 3.2 kb, which are reverse transcribed from RNA intermediates. Hepadnaviruses have a broad host range, which includes humans (hepatitis B virus), other mammals (genus Orthohepadnavirus), and birds (genus Avihepadnavirus). The known host specificity of hepadnaviruses has been expanded by reports of new viruses infecting fish, amphibians, and reptiles. Tibetan frog hepatitis B virus (TFHBV) was recently discovered in a member of the species Nanorana parkeri (family Dicroglossidae) from Tibet. To increase our understanding of hepadnaviruses that infect amphibian hosts, we identified the full-length genome of a divergent strain, TFHBV-Ot, associated with a concave-eared torrent frog (Odorrana tormota, family Ranidae) from China by searching deep-sequencing data. TFHBV-Ot shared a genomic organization and 76.6% overall genome sequence nucleotide identity with the prototype TFHBV associated with N. parkeri (TFHBV-Np). The pairwise amino acid sequence identity between the predicted gene products of TFHBV-Ot and TFHBV-Np ranged between 63.9% and 77.9%. Multiple tissue/organ-specific RNAseq datasets suggested a broad tropism of TFHBV, including muscle, gonads and brain. In addition, we provide information about putative virus-derived small RNAs from an amphibian hepadnavirus. The results presented here expand the known genetic diversity and host range of TFHBV to Ranidae frogs, and warrant an investigation of hepadnaviral infection of amphibian brains.Instituto de Patología VegetalFil: Debat, Humberto Julio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Fei Fan Ng, Terry. University of Georgia. College of Veterinary Medicine; Estados Unido
Arvind Varsani - One of the best experts on this subject based on the ideXlab platform.
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molecular characterisation of an Avihepadnavirus isolated from psittacula krameri ring necked parrot
Archives of Virology, 2012Co-Authors: Tomasz Piasecki, Brigitta Kurenbach, Klaudia Chrząstek, Karolina Julia Bednarek, Simona Kraberger, Darren P Martin, Arvind VarsaniAbstract:Avihepadnaviruses have been documented previously in ducks, herons, geese, storks and cranes. Here, we describe the full genome of a new Avihepadnavirus isolated from Psittacula krameri (ring-necked parrot) in Poland. The parrot hepatitis B virus (PHBV) genome (3042 bp) shares <76% sequence identity with other Avihepadnavirus isolates and is phylogenetically most closely related to heron and stork hepatitis B viruses isolates. PHBV has a genome organization similar to that of other hepadnaviruses and contains ORFs for a preC/C, preS/S and polyprotein. Additionally, we identified an X-like ORF in the genome of PHBV. The full-genome data will be useful in developing screening tools for Avihepadnaviruses in parrots.
Varsani Arvind - One of the best experts on this subject based on the ideXlab platform.
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Avihepadnavirus diversity in parrots is comparable to that found amongst all other avian species
Elsevier Inc., 2013Co-Authors: Piasecki Tomasz, Harkins, Gordon W., Chrząstek Klaudia, Julian Laurel, Martin, Darren P., Varsani ArvindAbstract:AbstractAvihepadnaviruses have previously been isolated from various species of duck, goose, stork, heron and crane. Recently the first parrot Avihepadnavirus was isolated from a Ring-necked Parakeet in Poland. In this study, 41 psittacine liver samples archived in Poland over the last nine years were tested for presence of Parrot hepatitis B virus (PHBV). We cloned and sequenced PHBV isolates from 18 birds including a Crimson Rosella, an African grey parrot and sixteen Ring-necked Parakeets. PHBV isolates display a degree of diversity (>78% genome wide pairwise identity) that is comparable to that found amongst all other Avihepadnaviruses (>79% genome wide pairwise identity). The PHBV viruses can be subdivided into seven genetically distinct groups (tentatively named A-G) of which the two isolated of PHBV-G are the most divergent sharing ∼79% genome wide pairwise identity with all their PHBVs. All PHBV isolates display classical Avihepadnavirus genome architecture
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Avihepadnavirus diversity in parrots is comparable to that found amongst all other avian species
'Elsevier BV', 2013Co-Authors: Piasecki Tomasz, Chrząstek Klaudia, Julian Laurel, Harkins, Gordon William, Martin, Darren Patrick, Varsani ArvindAbstract:Avihepadna viruses have previously been isolated from various species of duck ,goose, stork, heron and crane. Recently the first parrot avihepadna virus was isolated from a Ring-necked Parakeet in Poland. In this study, 41 psittacineliver samples archived in Poland over the last nine years were tested for presence of Parrot hepatitis B virus(PHBV). We cloned and sequenced PHBVisolates from 18 birds including a Crimson Rosella, an African grey parrot and sixteen Ring-necked Parakeets. PHBVisolates display a degree of diversity (478% genome wide pair wise identity) that is comparable to that found amongst all other avihepadna viruses (479% genome wide pair wise identity). The PHBV viruses can be subdivided into seven genetically distinct groups (tentatively named A-G) of which the two isolated of PHBV-Gare the most divergent sharing 79% genome wide pair wise identity with all their PHBVs. All PHBV isolates display classical Avihepadnavirus genome architecture.Department of HE and Training approved lis
Hans L. Zaaijer - One of the best experts on this subject based on the ideXlab platform.
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Protein X of hepatitis B virus: origin and structure similarity with the central domain of DNA glycosylase
2011Co-Authors: Formijn J. Van Hemert, Vladimir V. Lukashov, Neeltje A. Kootstra, Ben Berkhout, Hans L. ZaaijerAbstract:Orthohepadnavirus (mammalian hosts) and Avihepadnavirus (avian hosts) constitute the family of Hepadnaviridae and differ by their capability and inability for expression of protein X, respectively. Origin and functions of X are unclear. The evolutionary analysis at issue of X indicates that present strains of orthohepadnavirus started to diverge about 25,000 years ago, simultaneously with the onset of Avihepadnavirus diversification. These evolutionary events were preceded by a much longer period during which orthohepadnavirus developed a functional protein X while Avihepadnavirus evolved without X. An in silico generated 3D-model of orthohepadnaviral X protein displayed considerable similarity to the tertiary structure of DNA glycosylases (key enzymes of base excision DNA repair pathways). Similarity is confined to the central domain of MUG proteins with the typical DNA-binding facilities but without the capability of DNA glycosylase enzymatic activity. The hypothetical translation product of a vestigial X reading frame in the genome of duck hepadnavirus could also been folded into a DNA glycosylase-like 3D-structure. In conclusion, the most recent common ancestor of ortho- and avihepadnaviru
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Protein X of hepatitis B virus: origin and structure similarity with the central domain of DNA glycosylase.
Public Library of Science (PLoS), 2024Co-Authors: Formijn J. Van Hemert, Vladimir V. Lukashov, Neeltje A. Kootstra, Ben Berkhout, Maarten A A Van De Klundert, Hans L. ZaaijerAbstract:Orthohepadnavirus (mammalian hosts) and Avihepadnavirus (avian hosts) constitute the family of Hepadnaviridae and differ by their capability and inability for expression of protein X, respectively. Origin and functions of X are unclear. The evolutionary analysis at issue of X indicates that present strains of orthohepadnavirus started to diverge about 25,000 years ago, simultaneously with the onset of Avihepadnavirus diversification. These evolutionary events were preceded by a much longer period during which orthohepadnavirus developed a functional protein X while Avihepadnavirus evolved without X. An in silico generated 3D-model of orthohepadnaviral X protein displayed considerable similarity to the tertiary structure of DNA glycosylases (key enzymes of base excision DNA repair pathways). Similarity is confined to the central domain of MUG proteins with the typical DNA-binding facilities but without the capability of DNA glycosylase enzymatic activity. The hypothetical translation product of a vestigial X reading frame in the genome of duck hepadnavirus could also been folded into a DNA glycosylase-like 3D-structure. In conclusion, the most recent common ancestor of ortho- and Avihepadnavirus carried an X sequence with orthology to the central domain of DNA glycosylase
