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Karim Essani - One of the best experts on this subject based on the ideXlab platform.

  • Open Access Differential Susceptibility of Human Cancer Cell Lines to Wild-Type Tanapoxvirus Infection
    2013
    Co-Authors: Hui Lin Lee, Karim Essani
    Abstract:

    Abstract: Tanapoxvirus (TPV) is a member of the genus Yatapoxvirus in the family Poxviridae and is endemic to equatorial Africa. This disease is restricted to human and non-human primates, producing a mild febrile illness characterized by a single or more rarely additional pock-like lesions on the extremities. While there are several studies elucidating the replication cycle and host range of TPV, there is currently no standardized investigation comparing the ability of TPV to successfully replicate in a variety of tumor cell lines. This study examined the cytopathic effect and calculated the efficiency of TPV replication in vitro using 14 different human cancer cell lines. TPV replicates efficiently in some human tumor cells, and is restricted in others when measured by viral titer at 7 days post infection. Results described here clearly demonstrate that TPV replication in one glioblastoma cell line (U-373), and one colorectal cancer cell line (HCT-116) is more productive than in owl monkey kidney cells (OMK). Replication in two renal cancer cell lines (ACHN and Caki-1) is also increased when compared to OMK. TPV infection produced the greatest change in cellular morphology in U-373 cells, and to a much lesser degree in the breast cancer cell lines T-47D and MCF-7, and in the ovarian cancer line SK-OV3. Negligible change was noted in glioblastoma line U-87, breast cancer line MDA-MB-435, osteosarcoma line HOS, melanoma line SK-MEL5, colorectal cancer line COLO205, and prostate cancer line PC3. The cell lines least permissive to TPV replication were the glioblastoma (U-87) and melanoma (SK-MEL5) cell lines

  • Differential Susceptibility of Human Cancer Cell Lines to Wild-Type Tanapoxvirus Infection
    The open virology journal, 2010
    Co-Authors: Hui Lin Lee, Karim Essani
    Abstract:

    Tanapoxvirus (TPV) is a member of the genus Yatapoxvirus in the family Poxviridae and is endemic to equatorial Africa. This disease is restricted to human and non-human primates, producing a mild febrile illness characterized by a single or more rarely additional pock-like lesions on the extremities. While there are several studies elucidating the replication cycle and host range of TPV, there is currently no standardized investigation comparing the ability of TPV to successfully replicate in a variety of tumor cell lines. This study examined the cytopathic effect and calculated the efficiency of TPV replication in vitro using 14 different human cancer cell lines. TPV replicates efficiently in some human tumor cells, and is restricted in others when measured by viral titer at 7 days post infection. Results described here clearly demonstrate that TPV replication in one glioblastoma cell line (U-373), and one colorectal cancer cell line (HCT-116) is more productive than in owl monkey kidney cells (OMK). Replication in two renal cancer cell lines (ACHN and Caki-1) is also increased when compared to OMK. TPV infection produced the greatest change in cellular morphology in U-373 cells, and to a much lesser degree in the breast cancer cell lines T-47D and MCF-7, and in the ovarian cancer line SK-OV3. Negligible change was noted in glioblastoma line U-87, breast cancer line MDA-MB-435, osteosarcoma line HOS, melanoma line SK-MEL5, colorectal cancer line COLO205, and prostate cancer line PC3. The cell lines least permissive to TPV replication were the glioblastoma (U-87) and melanoma (SK-MEL5) cell lines.

  • Tropism of Tanapox virus infection in primary human cells
    Virology, 2007
    Co-Authors: Steven H. Nazarian, Karim Essani, John W. Barrett, Marianne M. Stanford, James B. Johnston, Grant Mcfadden
    Abstract:

    Tanapox virus (TPV) belongs to the genus Yatapoxvirus and causes a relatively benign zoonotic disease in man, with symptoms that resemble a mild version of human monkeypox. In order to investigate the underlying mechanisms of TPV pathogenesis, the tropism and replication characteristics of TPV were examined in a variety of primary human cells. A GFP expressing TPV (TPV-GFP) was constructed and used to infect primary human dermal fibroblasts (pHDFs) and peripheral blood mononuclear cells (PBMCs), both of which are believed to be major in vivo targets of poxvirus infection. pHDFs fully supported productive replication and cell–cell spread of TPV-GFP. However, induction of cell cycle arrest in pHDFs by contact mediated inhibition or rapamycin treatment eliminated the ability of TPV to fully stimulate cell cycle progression and dramatically reduced viral replication. TPV-GFP-infected human PBMCs were screened for permissiveness by FACS analysis. CD14+ cells (monocytes) were the primary cellular target for TPV infection. A small proportion of CD3+ cells (T cells) were positive for GFP expression, yet TPV was not able to replicate and spread in cultured peripheral blood lymphocytes, regardless of their state of activation. Primary human monocytes, however, demonstrated robust TPV replication, yet these cells no longer supported replication of TPV once they differentiated into macrophages. This unique ex vivo tropism of TPV gives key insights into the basis for the self-limiting pathogenicity of TPV in man.

  • The Genome Sequence of Yaba-like Disease Virus, a Yatapoxvirus☆
    Virology, 2001
    Co-Authors: Karim Essani
    Abstract:

    Abstract The genome sequence of Yaba-like disease virus (YLDV), an unclassified member of the Yatapoxvirus genus, has been determined. Excluding the terminal hairpin loops, the YLDV genome is 144,575 bp in length and contains inverted terminal repeats (ITRs) of 1883 bp. Within 20 nucleotides of the termini, there is a sequence that is conserved in other poxviruses and is required for the resolution of concatemeric replicative DNA intermediates. The nucleotide composition of the genome is 73% A+T, but the ITRs are only 63% A+T. The genome contains 151 tightly packed open reading frames (ORFs) that either are ≥180 nucleotides in length or are conserved in other poxviruses. ORFs within 23 kb of each end are transcribed toward the termini, whereas ORFs within the central region of the genome are encoded on either DNA strand. In the central region ORFs have a conserved position, orientation, and sequence compared with vaccinia virus ORFs and encode many enzymes, transcription factors, or structural proteins. In contrast, ORFs near the termini are more divergent and in seven cases are without counterparts in other poxviruses. The YLDV genome encodes several predicted immunomodulators; examples include two proteins with similarity to CC chemokine receptors and predicted secreted proteins with similarity to MHC class I antigen, OX-2, interleukin-10/mda-7, poxvirus growth factor, serpins, and a type I interferon-binding protein. Phylogenic analyses indicated that YLDV is very closely related to yaba monkey tumor virus, but outside the Yatapoxvirus genus YLDV is more closely related to swinepox virus and leporipoxviruses than to other chordopoxvirus genera.

Joon-hwa Lee - One of the best experts on this subject based on the ideXlab platform.

  • nmr study of hydrogen exchange during the b z transition of a dna duplex induced by the zα domains of Yatapoxvirus e3l
    FEBS Letters, 2010
    Co-Authors: Eun-hae Lee, Yeo-jin Seo, Hee-chul Ahn, Young-min Kang, Hee-eun Kim, Yeon-mi Lee, Byong-seok Choi, Joon-hwa Lee
    Abstract:

    The Yaba-like disease viruses (YLDV) are members of the Yatapoxvirus family and have double-stranded DNA genomes. The E3L protein, which is essential for pathogenesis in the vaccinia virus, consists of two domains: an N-terminal Z-DNA binding domain and a C-terminal RNA binding domain. The crystal structure of the E3L orthologue of YLDV (yabZαE3L) bound to Z-DNA revealed that the overall structure of yabZαE3L and its interaction with Z-DNA are very similar to those of hZαADAR1. Here we have performed NMR hydrogen exchange experiments on the complexes between yabZαE3L and d(CGCGCG)2 with a variety of protein-to-DNA molar ratios. This study revealed that yabZαE3L could efficiently change the B-form helix of the d(CGCGCG)2 to left-handed Z-DNA via the active-mono B–Z transition pathway like hZαADAR1.

  • NMR study of hydrogen exchange during the B–Z transition of a DNA duplex induced by the Zα domains of Yatapoxvirus E3L
    FEBS letters, 2010
    Co-Authors: Eun-hae Lee, Yeo-jin Seo, Hee-chul Ahn, Young-min Kang, Hee-eun Kim, Yeon-mi Lee, Byong-seok Choi, Joon-hwa Lee
    Abstract:

    The Yaba-like disease viruses (YLDV) are members of the Yatapoxvirus family and have double-stranded DNA genomes. The E3L protein, which is essential for pathogenesis in the vaccinia virus, consists of two domains: an N-terminal Z-DNA binding domain and a C-terminal RNA binding domain. The crystal structure of the E3L orthologue of YLDV (yabZαE3L) bound to Z-DNA revealed that the overall structure of yabZαE3L and its interaction with Z-DNA are very similar to those of hZαADAR1. Here we have performed NMR hydrogen exchange experiments on the complexes between yabZαE3L and d(CGCGCG)2 with a variety of protein-to-DNA molar ratios. This study revealed that yabZαE3L could efficiently change the B-form helix of the d(CGCGCG)2 to left-handed Z-DNA via the active-mono B–Z transition pathway like hZαADAR1.

Junpeng Deng - One of the best experts on this subject based on the ideXlab platform.

  • A Unique Bivalent Binding and Inhibition Mechanism by the Yatapoxvirus Interleukin 18 Binding Protein
    2016
    Co-Authors: Brian Krumm, Xiangzhi Meng, Zhixin Wang, Yan Xiang, Junpeng Deng
    Abstract:

    Interleukin 18 (IL18) is a cytokine that plays an important role in inflammation as well as host defense against microbes. Mammals encode a soluble inhibitor of IL18 termed IL18 binding protein (IL18BP) that modulates IL18 activity through a negative feedback mechanism. Many poxviruses encode homologous IL18BPs, which contribute to virulence. Previous structural and functional studies on IL18 and IL18BPs revealed an essential binding hot spot involving a lysine on IL18 and two aromatic residues on IL18BPs. The aromatic residues are conserved among the very diverse mammalian and poxviruses IL18BPs with the notable exception of Yatapoxvirus IL18BPs, which lack a critical phenylalanine residue. To understand the mechanism by which Yatapoxvirus IL18BPs neutralize IL18, we solved the crystal structure of the Yaba-Like Disease Virus (YLDV) IL18BP and IL18 complex at 1.75 A ̊ resolution. YLDV-IL18BP forms a disulfide bonded homo-dimer engaging IL18 in a 2:2 stoichiometry, in contrast to the 1:1 complex of ectromelia virus (ECTV) IL18BP and IL18. Disruption of the dimer interface resulted in a functional monomer, however with a 3-fold decrease in binding affinity. The overall architecture of the YLDV-IL18BP:IL18 complex is similar to that observed in the ECTV-IL18BP:IL18 complex, despite lacking the critical lysine-phenylalanine interaction. Through structural and mutagenesis studies, contact residues that are unique to the YLDV-IL18BP:IL18 binding interface were identified, including Q67, P116 of YLDV-IL18BP and Y1, S105 and D110 of IL18. Overall, our studies show that YLDV-IL18BP is unique among the diverse family of mammalian and poxvirus IL-18BPs in that it uses

  • A unique bivalent binding and inhibition mechanism by the Yatapoxvirus interleukin 18 binding protein.
    PLoS pathogens, 2012
    Co-Authors: Brian Krumm, Xiangzhi Meng, Zhixin Wang, Yan Xiang, Junpeng Deng
    Abstract:

    Interleukin 18 (IL18) is a cytokine that plays an important role in inflammation as well as host defense against microbes. Mammals encode a soluble inhibitor of IL18 termed IL18 binding protein (IL18BP) that modulates IL18 activity through a negative feedback mechanism. Many poxviruses encode homologous IL18BPs, which contribute to virulence. Previous structural and functional studies on IL18 and IL18BPs revealed an essential binding hot spot involving a lysine on IL18 and two aromatic residues on IL18BPs. The aromatic residues are conserved among the very diverse mammalian and poxviruses IL18BPs with the notable exception of Yatapoxvirus IL18BPs, which lack a critical phenylalanine residue. To understand the mechanism by which Yatapoxvirus IL18BPs neutralize IL18, we solved the crystal structure of the Yaba-Like Disease Virus (YLDV) IL18BP and IL18 complex at 1.75 A resolution. YLDV-IL18BP forms a disulfide bonded homo-dimer engaging IL18 in a 2∶2 stoichiometry, in contrast to the 1∶1 complex of ectromelia virus (ECTV) IL18BP and IL18. Disruption of the dimer interface resulted in a functional monomer, however with a 3-fold decrease in binding affinity. The overall architecture of the YLDV-IL18BP:IL18 complex is similar to that observed in the ECTV-IL18BP:IL18 complex, despite lacking the critical lysine-phenylalanine interaction. Through structural and mutagenesis studies, contact residues that are unique to the YLDV-IL18BP:IL18 binding interface were identified, including Q67, P116 of YLDV-IL18BP and Y1, S105 and D110 of IL18. Overall, our studies show that YLDV-IL18BP is unique among the diverse family of mammalian and poxvirus IL-18BPs in that it uses a bivalent binding mode and a unique set of interacting residues for binding IL18. However, despite this extensive divergence, YLDV-IL18BP binds to the same surface of IL18 used by other IL18BPs, suggesting that all IL18BPs use a conserved inhibitory mechanism by blocking a putative receptor-binding site on IL18.

Daniel L. Rock - One of the best experts on this subject based on the ideXlab platform.

  • Sheeppox Virus Kelch-Like Gene SPPV-019 Affects Virus Virulence
    Journal of Virology, 2007
    Co-Authors: Corey A Balinsky, Manuel V. Borca, G. Delhon, Guillermo R Risatti, E. R. Tulman, Richard A French, Claudio L Afonso, Steven J. Geary, Daniel L. Rock
    Abstract:

    Sheeppox virus (SPPV) is the etiologic agent of a highly significant disease of sheep and the type species of the genus Capripoxvirus, one of the eight genera of the subfamily Chordopoxvirinae of the Poxviridae (44). Other capripoxviruses (CaPVs) include goatpox virus (GTPV) and lumpy skin disease virus (LSDV), which cause disease in goats and cattle, respectively. Due to their significant economic impact and potential for disease transmission, CaPV diseases are listed diseases by the World Organization for Animal Health (OIE). Sheeppox is characterized by fever, ocular and nasal discharges, papular dermatitis, and nodular lesions in a variety of organs, including the lungs, trachea, and abomasum (6, 16). Young animals are most susceptible, where mortality rates can be as high as 50 to 70% (21, 26). Transmission of sheeppox is thought to require close contact between animals and to occur primarily via aerosol and respiratory droplet, though insect vectors have also been implicated (21, 26, 33, 34). Sheeppox is endemic throughout southwest and central Asia, the Indian subcontinent, and African regions north of the equator (9, 16). SPPV and other CaPVs are morphologically and serologically indistinguishable and genomically very similar, with overall conservation in genetic content and gene synteny and >96% nucleotide identity (7, 22, 32, 61). Comparison of field and vaccine strains has shown that relatively few genomic changes account for viral attenuation in CaPV. A number of these genes are predicted to affect virulence and host range (31, 61). Among the genes affected in vaccine strains of CaPV were those with products similar to kelch-like proteins encoded by eukaryotes and other poxviruses. Kelch-like proteins, including the prototype kelch encoded by Drosophila, are members of a protein superfamily characterized by the presence of kelch repeat motifs. These proteins also belong to a subset of proteins characterized by a C-terminal domain of multiple kelch repeats joined to a N-terminal BTB/POZ (for broad-complex, tramtrack and bric-a-brac/poxvirus and zinc finger) domain via a BACK (for BTB and C-terminal kelch) domain (1, 57, 58). Kelch-like proteins are encoded by metazoans and demonstrate considerable expansion in gene repertoire among vertebrates, with humans encoding more than 50 (48). Kelch-like proteins, whose BTB and kelch domains can mediate protein-protein interactions, affect multiple cellular processes, including cytoskeleton organization and dynamics, ion channel modulation, transcriptional regulation, and protein ubiquitination, where they serve as substrate adapter proteins that mediate interaction between ubiquitin ligase complexes and the substrates targeted for degradation (1, 2, 14, 20, 49). Kelch-like proteins are encoded by members of chordopoxviral genera Orthopoxvirus, Capripoxvirus, Leporipoxvirus, Suipoxvirus, and Yatapoxvirus and by unassigned deerpox viruses. Poxviral kelch-like genes are generally present as multiple, divergent, and occasionally fragmented genes located in variable and nonessential regions near genomic termini, leading to the suggestion that they function in aspects of virus-host interactions (55). Although domain structure is maintained, amino acid identity between poxviral and cellular kelch-like proteins is low. Studies examining the role of poxviral kelch-like genes in virus replication and pathogenesis have been limited to orthopoxviruses, where deletion of single or multiple kelch-like genes have been shown to affect lesion size, inflammatory cell infiltration, or virulence in a mouse model or vascularization and virus yield in a chorioallantoic membrane model of infection (4, 36, 47). These results have suggested a role for kelch-like genes in poxvirus virulence and host range, perhaps through the modulation of inflammatory responses (47). Still, the role of individual kelch-like proteins in poxvirus virulence remains to be fully elucidated. SPPV encodes three kelch-like proteins—SPPV-019, SPPV-144, and SPPV-151 (annotated as SPPV_16, SPPV_137, and SPPV_144, respectively, in NCBI Reference Sequence accession {"type":"entrez-nucleotide","attrs":{"text":"NC_004002","term_id":"21426071","term_text":"NC_004002"}}NC_004002)—that exhibit 93 to 95% amino acid identity to GTPV and LSDV orthologues (61). Examination of SPPV-019 orthologues in GTPV G20 and LSDV Neethling vaccine strains shows truncating frameshift mutations at positions 231 and 124, respectively, suggesting a role for CaPV SPPV-019-like genes in virus virulence (31, 60). In the present study, we examined the role of the kelch-like protein-encoding gene SPPV-019 in sheep, the natural SPPV host. Our data indicate that SPPV-019 markedly affects SPPV virulence after intranasal or intradermal virus inoculation.

  • The Genome of Swinepox Virus
    Journal of Virology, 2002
    Co-Authors: Claudio L Afonso, Corey A Balinsky, Fernando A. Osorio, Laszlo Zsak, Gerald F. Kutish, E. R. Tulman, Z Lu, Daniel L. Rock
    Abstract:

    Swinepox virus (SWPV), the sole member of the Suipoxvirus genus of the Poxviridae , is the etiologic agent of a worldwide disease specific for swine. Here we report the genomic sequence of SWPV. The 146-kbp SWPV genome consists of a central coding region bounded by identical 3.7-kbp inverted terminal repeats and contains 150 putative genes. Comparison of SWPV with chordopoxviruses reveals 146 conserved genes encoding proteins involved in basic replicative functions, viral virulence, host range, and immune evasion. Notably, these include genes with similarity to genes for gamma interferon (IFN-γ) receptor, IFN resistance protein, interleukin-18 binding protein, IFN-α/β binding protein, extracellular enveloped virus host range protein, dUTPase, hydroxysteroid dehydrogenase, superoxide dismutase, serpin, herpesvirus major histocompatibility complex inhibitor, ectromelia virus macrophage host range protein, myxoma virus M011L, variola virus B22R, four ankyrin repeat proteins, three kelch-like proteins, five vaccinia virus (VV) A52R-like family proteins, and two G protein-coupled receptors. The most conserved genomic region is centrally located and corresponds to the VV region located between genes F9L and A38L. Within the terminal 13 kbp, colinearity is disrupted and multiple poxvirus gene homologues are absent or share a lower percentage of amino acid identity. Most of these differences involve genes and gene families with likely functions involving viral virulence and host range. Three open reading frames (SPV018, SPV019. and SPV020) are unique for SWPV. Phylogenetic analysis, genome organization, and amino acid identity indicate that SWPV is most closely related to the capripoxvirus lumpy skin disease virus, followed by the Yatapoxvirus yaba-like disease virus and the leporipoxviruses. The gene complement of SWPV better defines Suipoxvirus within the Chordopoxvirinae subfamily and provides a basis for future genetic comparisons.

  • The Genome of Swinepox Virus
    Journal of virology, 2002
    Co-Authors: Claudio L Afonso, Corey A Balinsky, Fernando A. Osorio, Laszlo Zsak, Gerald F. Kutish, E. R. Tulman, Daniel L. Rock
    Abstract:

    Swinepox virus (SWPV), the sole member of the Suipoxvirus genus of the Poxviridae, is the etiologic agent of a worldwide disease specific for swine. Here we report the genomic sequence of SWPV. The 146-kbp SWPV genome consists of a central coding region bounded by identical 3.7-kbp inverted terminal repeats and contains 150 putative genes. Comparison of SWPV with chordopoxviruses reveals 146 conserved genes encoding proteins involved in basic replicative functions, viral virulence, host range, and immune evasion. Notably, these include genes with similarity to genes for gamma interferon (IFN-gamma) receptor, IFN resistance protein, interleukin-18 binding protein, IFN-alpha/beta binding protein, extracellular enveloped virus host range protein, dUTPase, hydroxysteroid dehydrogenase, superoxide dismutase, serpin, herpesvirus major histocompatibility complex inhibitor, ectromelia virus macrophage host range protein, myxoma virus M011L, variola virus B22R, four ankyrin repeat proteins, three kelch-like proteins, five vaccinia virus (VV) A52R-like family proteins, and two G protein-coupled receptors. The most conserved genomic region is centrally located and corresponds to the VV region located between genes F9L and A38L. Within the terminal 13 kbp, colinearity is disrupted and multiple poxvirus gene homologues are absent or share a lower percentage of amino acid identity. Most of these differences involve genes and gene families with likely functions involving viral virulence and host range. Three open reading frames (SPV018, SPV019. and SPV020) are unique for SWPV. Phylogenetic analysis, genome organization, and amino acid identity indicate that SWPV is most closely related to the capripoxvirus lumpy skin disease virus, followed by the Yatapoxvirus yaba-like disease virus and the leporipoxviruses. The gene complement of SWPV better defines Suipoxvirus within the Chordopoxvirinae subfamily and provides a basis for future genetic comparisons.

Eun-hae Lee - One of the best experts on this subject based on the ideXlab platform.

  • nmr study of hydrogen exchange during the b z transition of a dna duplex induced by the zα domains of Yatapoxvirus e3l
    FEBS Letters, 2010
    Co-Authors: Eun-hae Lee, Yeo-jin Seo, Hee-chul Ahn, Young-min Kang, Hee-eun Kim, Yeon-mi Lee, Byong-seok Choi, Joon-hwa Lee
    Abstract:

    The Yaba-like disease viruses (YLDV) are members of the Yatapoxvirus family and have double-stranded DNA genomes. The E3L protein, which is essential for pathogenesis in the vaccinia virus, consists of two domains: an N-terminal Z-DNA binding domain and a C-terminal RNA binding domain. The crystal structure of the E3L orthologue of YLDV (yabZαE3L) bound to Z-DNA revealed that the overall structure of yabZαE3L and its interaction with Z-DNA are very similar to those of hZαADAR1. Here we have performed NMR hydrogen exchange experiments on the complexes between yabZαE3L and d(CGCGCG)2 with a variety of protein-to-DNA molar ratios. This study revealed that yabZαE3L could efficiently change the B-form helix of the d(CGCGCG)2 to left-handed Z-DNA via the active-mono B–Z transition pathway like hZαADAR1.

  • NMR study of hydrogen exchange during the B–Z transition of a DNA duplex induced by the Zα domains of Yatapoxvirus E3L
    FEBS letters, 2010
    Co-Authors: Eun-hae Lee, Yeo-jin Seo, Hee-chul Ahn, Young-min Kang, Hee-eun Kim, Yeon-mi Lee, Byong-seok Choi, Joon-hwa Lee
    Abstract:

    The Yaba-like disease viruses (YLDV) are members of the Yatapoxvirus family and have double-stranded DNA genomes. The E3L protein, which is essential for pathogenesis in the vaccinia virus, consists of two domains: an N-terminal Z-DNA binding domain and a C-terminal RNA binding domain. The crystal structure of the E3L orthologue of YLDV (yabZαE3L) bound to Z-DNA revealed that the overall structure of yabZαE3L and its interaction with Z-DNA are very similar to those of hZαADAR1. Here we have performed NMR hydrogen exchange experiments on the complexes between yabZαE3L and d(CGCGCG)2 with a variety of protein-to-DNA molar ratios. This study revealed that yabZαE3L could efficiently change the B-form helix of the d(CGCGCG)2 to left-handed Z-DNA via the active-mono B–Z transition pathway like hZαADAR1.