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A Tanaka - One of the best experts on this subject based on the ideXlab platform.

  • 2 gene families of Mareks Disease virus mdv with a potential role in tumor induction in chicken review
    International Journal of Oncology, 1995
    Co-Authors: Hsingjien Kung, A Tanaka, M Nonoyama
    Abstract:

    Marek's Disease virus (MDV) is one of the most oncogenic herpesviruses and the only cancer virus that has a successful vaccine. Based on the short-latency and polyclonal nature of the tumors, it is likely that MDV encodes its own oncogenes. Recent studies have provided insights into possible MDV genes involved in oncogenesis. We describe the characterization of two gene families encoded by the BamHI-H and I-2 fragments. The BamHI-H and I-2 fragments, located contiguously in the IR(L) region, are unique to oncogenic (serotype) MDV and consistently expressed in MDV-transformed tumors and T-cell lines. The structural alteration of the BamHI-H fragment, specifically the expansion of a 132 bp repeat, has been correlated with the attenuation of the oncogenicity of MDV. Several open-reading frames, some resulting from alternative splicing, can be identified. One of the open-reading frames, BHa, encodes a 7 Kd polypeptide. BHa shares limited homology with a T-cell lymphoma oncogene TLM and stimulates extended growth of chicken embryo fibroblasts, when transfected into the cell. The other gene implicated in latency or oncogenesis is Meg whose coding sequences span portion of the BamHI-I-2 and the Q(2) fragment. Meq has an interesting structure, resembling a chimera between Jun/Fos oncoproteins and WT-1 tumor suppressor protein. It contains a bZIP (basic leucine zipper) domain and a long proline-rich domain. The proline domain has trans-activating function, whereas the bZIP domain allows Meq to dimerize with a variety of transcriptional factors and expands the enhancer repertoire it acts on. As neoplastic transformation usually requires the complementation of multiple oncogenes, BHa and Meq could be two of the proteins participating in this process.

  • a 7 kda protein encoded by the bamhi h gene family of Mareks Disease virus is produced in lytically and latently infected cells
    International Journal of Oncology, 1994
    Co-Authors: Fangyu Peng, A Tanaka, S Specter, Meihan Nonoyama
    Abstract:

    Marek's Disease virus (MDV) BamHI-H gene family was transcribed specifically in cells infected with oncogenic MDV, and the transcripts were prematurely terminated in cells infected with non-oncogenic attenuated strains of MDV due to the amplification of a 132 bp repeat located downstream of their promoter. There are six small open reading frames in the two differently spliced and two unspliced transcripts. This report describes expression of BHa gene open reading frame A, present in 1.7 kb unspliced transcript. Antibody was raised against BHa C-terminal polypeptide. The antibody showed specific reaction to the GST fusion protein derived from BHa protein. Immunoprecipitation with the lysates of infected cells was carried out. The results indicated that 7 kDa BHa protein was immunoprecipitated from the lysates of oncogenic MDV infected chicken embryo fibroblasts (CEF) and a MSB-1 lymphoblastoid cell line derived from Marek's Disease tumor but not from non-oncogenic MDV infected CEF or uninfected CEF. 36 kDa protein was co-immunoprecipitated with 7 kDa BHa protein in oncogenic MDV infected CEF but was not detected in MSB-1 cells. This is the first report to show that a small open reading frame of the BamHI-H gene family was in fact expressed in MDV infected cells.

  • prolonged proliferation of primary chicken embryo fibroblasts transfected with cdnas from the bamhi h gene family of Mareks Disease virus
    International Journal of Oncology, 1993
    Co-Authors: Fangyu Peng, A Tanaka, J Donovan, S Specter, Meihan Nonoyama
    Abstract:

    Oncogenic virus-specific 1.69 kb and 1.5 kb cDNAs, derived from the tumorigenicity-associated BamHI-H gene family of Marek's Disease virus (MDV), were cloned into the eukaryotic expression vector (PRC/CMV) and designated as PRC/CMV-1.69 and PRC/CMV-1.5, respectively. Chicken embryo fibroblasts (CEFs) transfected with PRC/CMV-1.69 or PRC/CMV-1.5 plasmid DNA showed reduced serum-dependence for growth compared with PRC/CMV vector-transfected CEFs. Also, PRC/CMV-1.69 or PRC/CMV-1.5 DNA transfected CEFs proliferated for a longer period of time (20-22 passages) compared with the CEFs transfected with PRC/CMV plasmid DNA (10 passages). Reduced serum-dependence for growth and prolonged proliferation of CEFs after in vitro transfection with PRC/CMV-1.69 or PRC/CMV-1.5 indicated that these two cDNAs stimulate cell growth. These data indicated that one of the functions of the BamHI-H gene family of MDV is cell-growth control, which may play an important role in the establishment and maintenance of uncontrolled growth of tumor cells induced by MDV.

Meihan Nonoyama - One of the best experts on this subject based on the ideXlab platform.

  • a 7 kda protein encoded by the bamhi h gene family of Mareks Disease virus is produced in lytically and latently infected cells
    International Journal of Oncology, 1994
    Co-Authors: Fangyu Peng, A Tanaka, S Specter, Meihan Nonoyama
    Abstract:

    Marek's Disease virus (MDV) BamHI-H gene family was transcribed specifically in cells infected with oncogenic MDV, and the transcripts were prematurely terminated in cells infected with non-oncogenic attenuated strains of MDV due to the amplification of a 132 bp repeat located downstream of their promoter. There are six small open reading frames in the two differently spliced and two unspliced transcripts. This report describes expression of BHa gene open reading frame A, present in 1.7 kb unspliced transcript. Antibody was raised against BHa C-terminal polypeptide. The antibody showed specific reaction to the GST fusion protein derived from BHa protein. Immunoprecipitation with the lysates of infected cells was carried out. The results indicated that 7 kDa BHa protein was immunoprecipitated from the lysates of oncogenic MDV infected chicken embryo fibroblasts (CEF) and a MSB-1 lymphoblastoid cell line derived from Marek's Disease tumor but not from non-oncogenic MDV infected CEF or uninfected CEF. 36 kDa protein was co-immunoprecipitated with 7 kDa BHa protein in oncogenic MDV infected CEF but was not detected in MSB-1 cells. This is the first report to show that a small open reading frame of the BamHI-H gene family was in fact expressed in MDV infected cells.

  • prolonged proliferation of primary chicken embryo fibroblasts transfected with cdnas from the bamhi h gene family of Mareks Disease virus
    International Journal of Oncology, 1993
    Co-Authors: Fangyu Peng, A Tanaka, J Donovan, S Specter, Meihan Nonoyama
    Abstract:

    Oncogenic virus-specific 1.69 kb and 1.5 kb cDNAs, derived from the tumorigenicity-associated BamHI-H gene family of Marek's Disease virus (MDV), were cloned into the eukaryotic expression vector (PRC/CMV) and designated as PRC/CMV-1.69 and PRC/CMV-1.5, respectively. Chicken embryo fibroblasts (CEFs) transfected with PRC/CMV-1.69 or PRC/CMV-1.5 plasmid DNA showed reduced serum-dependence for growth compared with PRC/CMV vector-transfected CEFs. Also, PRC/CMV-1.69 or PRC/CMV-1.5 DNA transfected CEFs proliferated for a longer period of time (20-22 passages) compared with the CEFs transfected with PRC/CMV plasmid DNA (10 passages). Reduced serum-dependence for growth and prolonged proliferation of CEFs after in vitro transfection with PRC/CMV-1.69 or PRC/CMV-1.5 indicated that these two cDNAs stimulate cell growth. These data indicated that one of the functions of the BamHI-H gene family of MDV is cell-growth control, which may play an important role in the establishment and maintenance of uncontrolled growth of tumor cells induced by MDV.

M Nonoyama - One of the best experts on this subject based on the ideXlab platform.

  • 2 gene families of Mareks Disease virus mdv with a potential role in tumor induction in chicken review
    International Journal of Oncology, 1995
    Co-Authors: Hsingjien Kung, A Tanaka, M Nonoyama
    Abstract:

    Marek's Disease virus (MDV) is one of the most oncogenic herpesviruses and the only cancer virus that has a successful vaccine. Based on the short-latency and polyclonal nature of the tumors, it is likely that MDV encodes its own oncogenes. Recent studies have provided insights into possible MDV genes involved in oncogenesis. We describe the characterization of two gene families encoded by the BamHI-H and I-2 fragments. The BamHI-H and I-2 fragments, located contiguously in the IR(L) region, are unique to oncogenic (serotype) MDV and consistently expressed in MDV-transformed tumors and T-cell lines. The structural alteration of the BamHI-H fragment, specifically the expansion of a 132 bp repeat, has been correlated with the attenuation of the oncogenicity of MDV. Several open-reading frames, some resulting from alternative splicing, can be identified. One of the open-reading frames, BHa, encodes a 7 Kd polypeptide. BHa shares limited homology with a T-cell lymphoma oncogene TLM and stimulates extended growth of chicken embryo fibroblasts, when transfected into the cell. The other gene implicated in latency or oncogenesis is Meg whose coding sequences span portion of the BamHI-I-2 and the Q(2) fragment. Meq has an interesting structure, resembling a chimera between Jun/Fos oncoproteins and WT-1 tumor suppressor protein. It contains a bZIP (basic leucine zipper) domain and a long proline-rich domain. The proline domain has trans-activating function, whereas the bZIP domain allows Meq to dimerize with a variety of transcriptional factors and expands the enhancer repertoire it acts on. As neoplastic transformation usually requires the complementation of multiple oncogenes, BHa and Meq could be two of the proteins participating in this process.

Fangyu Peng - One of the best experts on this subject based on the ideXlab platform.

  • a 7 kda protein encoded by the bamhi h gene family of Mareks Disease virus is produced in lytically and latently infected cells
    International Journal of Oncology, 1994
    Co-Authors: Fangyu Peng, A Tanaka, S Specter, Meihan Nonoyama
    Abstract:

    Marek's Disease virus (MDV) BamHI-H gene family was transcribed specifically in cells infected with oncogenic MDV, and the transcripts were prematurely terminated in cells infected with non-oncogenic attenuated strains of MDV due to the amplification of a 132 bp repeat located downstream of their promoter. There are six small open reading frames in the two differently spliced and two unspliced transcripts. This report describes expression of BHa gene open reading frame A, present in 1.7 kb unspliced transcript. Antibody was raised against BHa C-terminal polypeptide. The antibody showed specific reaction to the GST fusion protein derived from BHa protein. Immunoprecipitation with the lysates of infected cells was carried out. The results indicated that 7 kDa BHa protein was immunoprecipitated from the lysates of oncogenic MDV infected chicken embryo fibroblasts (CEF) and a MSB-1 lymphoblastoid cell line derived from Marek's Disease tumor but not from non-oncogenic MDV infected CEF or uninfected CEF. 36 kDa protein was co-immunoprecipitated with 7 kDa BHa protein in oncogenic MDV infected CEF but was not detected in MSB-1 cells. This is the first report to show that a small open reading frame of the BamHI-H gene family was in fact expressed in MDV infected cells.

  • prolonged proliferation of primary chicken embryo fibroblasts transfected with cdnas from the bamhi h gene family of Mareks Disease virus
    International Journal of Oncology, 1993
    Co-Authors: Fangyu Peng, A Tanaka, J Donovan, S Specter, Meihan Nonoyama
    Abstract:

    Oncogenic virus-specific 1.69 kb and 1.5 kb cDNAs, derived from the tumorigenicity-associated BamHI-H gene family of Marek's Disease virus (MDV), were cloned into the eukaryotic expression vector (PRC/CMV) and designated as PRC/CMV-1.69 and PRC/CMV-1.5, respectively. Chicken embryo fibroblasts (CEFs) transfected with PRC/CMV-1.69 or PRC/CMV-1.5 plasmid DNA showed reduced serum-dependence for growth compared with PRC/CMV vector-transfected CEFs. Also, PRC/CMV-1.69 or PRC/CMV-1.5 DNA transfected CEFs proliferated for a longer period of time (20-22 passages) compared with the CEFs transfected with PRC/CMV plasmid DNA (10 passages). Reduced serum-dependence for growth and prolonged proliferation of CEFs after in vitro transfection with PRC/CMV-1.69 or PRC/CMV-1.5 indicated that these two cDNAs stimulate cell growth. These data indicated that one of the functions of the BamHI-H gene family of MDV is cell-growth control, which may play an important role in the establishment and maintenance of uncontrolled growth of tumor cells induced by MDV.

Mehdi Golshan - One of the best experts on this subject based on the ideXlab platform.

  • molecular study for detection of Mareks Disease virus mdv in southwest of iran
    Scientific Research and Essays, 2011
    Co-Authors: Abbas Doosti, Mehdi Golshan
    Abstract:

    Marek´s Disease (MD), a lymphoproliferative Disease of domestic chickens, is caused by an “alphaherpesvirus”. MD viruses cause clinical manifestations can be numerous and varied, including paralysis, skin lesions, atrophy of the thymus and bursa of Fabricius immunosuppression and high mortality. The aim of the present study was diagnosis of MDV (Marek´s Disease virus) using PCR. In order to perform this study, blood and tumoral tissue samples were collected from slaughter houses of Chaharmahal Va Bakhtiari province in southwest of Iran. After DNA extraction from samples, polymerase chain reaction (PCR) was performed using specific primers detecting “antigen A” gene and 132 bp sequences of MDV, finally electrophoresis of PCR products was done in 1% agarose gel. The results of this study showed no positive sample for “MDV” and vaccinal strain, but in tumoral tissues two fragments, about 314 and 434 bp length identified for positive cases. In total, from 280 samples 62.86% were positive on PCR analysis. Serotype 1 of Marek’s Disease virus was detected as a causative agent for tumors in the chicken farms of Iran by PCR. Since all the samples have clinical symptoms of Marek´s Disease, but 62.86% of our samples infected for this virus. According to these results it seems to be that other factors, except the MDV, have a role in tumor lesions in poultry.   Key words: Marek’s Disease virus, chicken, polymerase chain reaction, Iran.