The Experts below are selected from a list of 9762 Experts worldwide ranked by ideXlab platform
John J. Rossi - One of the best experts on this subject based on the ideXlab platform.
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RNAi as a treatment for HIV-1 infection.
BioTechniques, 2006Co-Authors: John J. RossiAbstract:Human immunodeficiency Virus type 1 (HIV-1) was the first Primate Virus shown to be inhibited by RNA interference (RNAi). Early studies used both synthetic and promoter expressed small interfering ...
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RNAi as a treatment for HIV-1 infection.
BioTechniques, 2006Co-Authors: John J. RossiAbstract:Human immunodeficiency Virus type 1 (HIV-1) was the first Primate Virus shown to be inhibited by RNA interference (RNAi). Early studies used both synthetic and promoter expressed small interfering RNAs (siRNAs) or expressed short hairpin RNAs (shRNAs) to demonstrate that this Virus was susceptible to RNAi. In addition to targeting the Virus itself RNAi-mediated down-regulation of cellular targets that encode receptors required for viral entry also proved to be effective. The power of RNAi as an anti-HIV agent has propelled development of RNAi-based gene therapy approaches for the treatment of HIV infection in humans. Nevertheless, extensive in vitro experimentation has revealed potential problems of viral escape mutants and other toxicities caused by the si/shRNAs. This review covers the progress and problems in the development of RNAi for the treatment of HIV infection. Potential modalities for clinical application of RNAi in the treatment of HIV-1 infection are also described.
Darla Black - One of the best experts on this subject based on the ideXlab platform.
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Sequence analysis of herpes simplex VirusgB gene homologs of two platyrrhine monkey α-herpesViruses
Archives of Virology, 1993Co-Authors: R. Eberle, Darla BlackAbstract:Homologs of the herpes simplex Virus gB gene were identified in two α-herpesViruses of platyrrhine monkeys, HerpesVirus saimiri 1 (HVS 1) and H. ateles 1 (HVA 1). These genes were cloned and sequenced in their entirety. Analysis of the predicted amino acid sequences indicated that the gB glycoproteins of these two Viruses are of similar size, have 10 Cys residues and 5 potential N-linked glycosylation sites which align exactly with those in other Primate α-herpesVirus gB polypeptides, and have a similar distribution of predicted secondary structural features, all of which indicate a conserved structure of the gB polypeptide. Alignment of these two gB sequences with those of four other Primate α-herpesViruses (SA 8, B Virus, HSV 1 and HSV 2) revealed localized regions of extensive sequence divergence as well as highly conserved regions. On comparison of the six Primate Virus gB sequences, the gBs of the two platyrrhine monkey Viruses form a subgroup separate from that of the four catarrhine Virus gBs. The degree of relatedness of the HVA 1 and HVS 1 gB sequences to each other was equivalent to the degree of relatedness between the human and the cercopithecine monkey Virus gB sequences.
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Sequence analysis of herpes simplex Virus gB gene homologs of two platyrrhine monkey alpha-herpesViruses.
Archives of virology, 1993Co-Authors: R. Eberle, Darla BlackAbstract:Homologs of the herpes simplex Virus gB gene were identified in two alpha-herpesViruses of platyrrhine monkeys, HerpesVirus saimiri 1 (HVS 1) and H. ateles 1 (HVA 1). These genes were cloned and sequenced in their entirety. Analysis of the predicted amino acid sequences indicated that the gB glycoproteins of these two Viruses are of similar size, have 10 Cys residues and 5 potential N-linked glycosylation sites which align exactly with those in other Primate alpha-herpesVirus gB polypeptides, and have a similar distribution of predicted secondary structural features, all of which indicate a conserved structure of the gB polypeptide. Alignment of these two gB sequences with those of four other Primate alpha-herpesViruses (SA 8, B Virus, HSV 1 and HSV 2) revealed localized regions of extensive sequence divergence as well as highly conserved regions. On comparison of the six Primate Virus gB sequences, the gBs of the two platyrrhine monkey Viruses form a subgroup separate from that of the four catarrhine Virus gBs. The degree of relatedness of the HVA 1 and HVS 1 gB sequences to each other was equivalent to the degree of relatedness between the human and the cercopithecine monkey Virus gB sequences.
Sheila A. Hazlewood - One of the best experts on this subject based on the ideXlab platform.
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HerpesVirus pan encodes a functional homologue of BHRF1, the Epstein-Barr Virus v-Bcl-2
BMC Microbiology, 2005Co-Authors: Melanie Howell, Tracey Williams, Sheila A. HazlewoodAbstract:Background Epstein-Barr Virus (EBV) latently infects about 90% of the human population and is associated with benign and malignant diseases of lymphoid and epithelial origin. BHRF1, an early lytic cycle antigen, is an apoptosis suppressing member of the Bcl-2 family. In vitro studies imply that BHRF1 is dispensable for both Virus replication and transformation. However, the fact that BHRF1 is highly conserved not only in all EBV isolates studied to date but also in the analogous Viruses HerpesVirus papio and HerpesVirus pan that infect baboons and chimpanzees respectively, suggests BHRF1 may play an important role in vivo . Results HerpesVirus papio BHRF1 has been shown to function in an analogous manner to EBV BHRF1 in response to DNA damaging agents in human keratinocytes. In this study we show that the heterologous expression of the previously uncharacterised HerpesVirus pan BHRF1 in the human Burkitt's lymphoma cell line Ramos-BL provides similar anti-apoptotic functions to that of EBV BHRF1 in response to apoptosis triggered by serum withdrawal, etoposide treatment and ultraviolet (UV) radiation. We also map the amino acid changes onto the recently solved structure of the EBV BHRF1 and reveal that these changes are unlikely to alter the 3D structure of the protein. Conclusions These findings show that the functional conservation of BHRF1 extends to a lymphoid background, suggesting that the Primate Virus proteins interact with cellular proteins that are themselves highly conserved across the higher Primates. Further weight is added to this suggestion when we show that the difference in amino acid sequences map to regions on the 3D structure of EBV BHRF1 that are unlikely to change the conformation of the protein.
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BHRF1 is highly conserved in Primate Virus analogues of Epstein-Barr Virus.
Intervirology, 2001Co-Authors: Tracey Williams, Darleen Sale, Sheila A. HazlewoodAbstract:The Epstein-Barr Virus (EBV) protein BHRF1 (BamHI rightward reading frame 1) was the first viral member of the Bcl-2 family of apoptosis-regulating proteins described. In vitro studies imply that BHRF1 is dispensable for Virus-induced cellular transformation and Virus replication. However, in contrast to several essential viral genes that show divergence outwith their functional domains, sequence data from a wide range of EBV isolates show there is striking conservation of the BHRF1 gene. Contrary to the in vitro studies, the high degree of conservation hints at a more important role for BHRF1. Analogous Viruses are endemic in each of the higher Primate species. Whilst their genome organisation is colinear, limited sequence analysis indicates that the Viruses have diverged significantly and that only important functional domains of proteins are likely to be conserved. We have isolated the BHRF1 equivalents from the Viruses which infect chimpanzees (HerpesVirus pan) and baboons (HerpesVirus papio) and find that they are highly homologous in both species, strengthening the hypothesis that BHRF1 plays a significant, evolutionarily conserved function in vivo and that changes to the protein are not well tolerated.
R. Eberle - One of the best experts on this subject based on the ideXlab platform.
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Sequence analysis of herpes simplex VirusgB gene homologs of two platyrrhine monkey α-herpesViruses
Archives of Virology, 1993Co-Authors: R. Eberle, Darla BlackAbstract:Homologs of the herpes simplex Virus gB gene were identified in two α-herpesViruses of platyrrhine monkeys, HerpesVirus saimiri 1 (HVS 1) and H. ateles 1 (HVA 1). These genes were cloned and sequenced in their entirety. Analysis of the predicted amino acid sequences indicated that the gB glycoproteins of these two Viruses are of similar size, have 10 Cys residues and 5 potential N-linked glycosylation sites which align exactly with those in other Primate α-herpesVirus gB polypeptides, and have a similar distribution of predicted secondary structural features, all of which indicate a conserved structure of the gB polypeptide. Alignment of these two gB sequences with those of four other Primate α-herpesViruses (SA 8, B Virus, HSV 1 and HSV 2) revealed localized regions of extensive sequence divergence as well as highly conserved regions. On comparison of the six Primate Virus gB sequences, the gBs of the two platyrrhine monkey Viruses form a subgroup separate from that of the four catarrhine Virus gBs. The degree of relatedness of the HVA 1 and HVS 1 gB sequences to each other was equivalent to the degree of relatedness between the human and the cercopithecine monkey Virus gB sequences.
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Sequence analysis of herpes simplex Virus gB gene homologs of two platyrrhine monkey alpha-herpesViruses.
Archives of virology, 1993Co-Authors: R. Eberle, Darla BlackAbstract:Homologs of the herpes simplex Virus gB gene were identified in two alpha-herpesViruses of platyrrhine monkeys, HerpesVirus saimiri 1 (HVS 1) and H. ateles 1 (HVA 1). These genes were cloned and sequenced in their entirety. Analysis of the predicted amino acid sequences indicated that the gB glycoproteins of these two Viruses are of similar size, have 10 Cys residues and 5 potential N-linked glycosylation sites which align exactly with those in other Primate alpha-herpesVirus gB polypeptides, and have a similar distribution of predicted secondary structural features, all of which indicate a conserved structure of the gB polypeptide. Alignment of these two gB sequences with those of four other Primate alpha-herpesViruses (SA 8, B Virus, HSV 1 and HSV 2) revealed localized regions of extensive sequence divergence as well as highly conserved regions. On comparison of the six Primate Virus gB sequences, the gBs of the two platyrrhine monkey Viruses form a subgroup separate from that of the four catarrhine Virus gBs. The degree of relatedness of the HVA 1 and HVS 1 gB sequences to each other was equivalent to the degree of relatedness between the human and the cercopithecine monkey Virus gB sequences.
Guerline Clerzius - One of the best experts on this subject based on the ideXlab platform.
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Dual role of TRBP in HIV replication and RNA interference: viral diversion of a cellular pathway or evasion from antiviral immunity?
Retrovirology, 2005Co-Authors: Anne Gatignol, Sébastien Lainé, Guerline ClerziusAbstract:Increasing evidence indicates that RNA interference (RNAi) may be used to provide antiviral immunity in mammalian cells. Human micro (mi)RNAs can inhibit the replication of a Primate Virus, whereas a virally-encoded miRNA from HIV inhibits its own replication. Indirect proof comes from RNAi suppressors encoded by mammalian Viruses. Influenza NS1 and Vaccinia E3L proteins can inhibit RNAi in plants, insects and worms. HIV-1 Tat protein and AdenoVirus VA RNAs act as RNAi suppressors in mammalian cells. Surprisingly, many RNAi suppressors are also inhibitors of the interferon (IFN)-induced protein kinase R (PKR) but the potential overlap between the RNAi and the IFN pathways remains to be determined. The link between RNAi as an immune response and the IFN pathway may be formed by a cellular protein, TRBP, which has a dual role in HIV replication and RNAi. TRBP has been isolated as an HIV-1 TAR RNA binding protein that increases HIV expression and replication by inhibiting PKR and by increasing translation of structured RNAs. A recent report published in the Journal of Virology shows that the poor replication of HIV in astrocytes is mainly due to a heightened PKR response that can be overcome by supplying TRBP exogenously. In two recent papers published in Nature and EMBO Reports, TRBP is now shown to interact with Dicer and to be required for RNAi mediated by small interfering (si) and micro (mi)RNAs. The apparent discrepancy between TRBP requirement in RNAi and in HIV replication opens the hypotheses that RNAi may be beneficial for HIV-1 replication or that HIV-1 may evade the RNAi restriction by diverting TRBP from Dicer and use it for its own benefit.