We investigated inhibition of Moloney leukemia virus 10 (MOV10) upon xenotropic murine leukemia virus-related virus (XMRV) and made a preliminary study of the mechanism of action. Using transfection, infection, western blotting and real-time polymerase chain reaction, we found that MOV10 inhibited XMRV replication. Using MOV10 overexpressed in viral producer cells, MOV10 was shown to reduce the infectivity of XMRV. MOV10 could be incorporated into XMRV, suggesting that MOV10 could undergo encapsidation by XMRV during viral assembly. MOV10 could also restrict the DNA production of XMRV in target cells. We found that the putative RNA-helicase domain of MOV10 maintained most of its XMRV inhibition. These results suggest that MOV10 could be required during the retroviral lifecycle. Perturbation of MOV10 disrupts the generation of infectious viral particles, suggesting that MOV10 has broad antiretroviral activity. Hence, MOV10 could be actively involved in host defense against retroviral infection.
Humans ; Moloney murine leukemia virus ; physiology ; RNA Helicases ; physiology ; Virus Replication

OBJECTIVES: To evaluate the effect of glutathione(GSH) on lead induced modulation of nitric oxide(NO) synthesis, and to examine how lead modulates NO production in macrophages. METHODS: This study was observed in a culture of RAW 264.7 cells, which originated from a tumor in a Balb/c mouse that was induced by the Abelson murine leukemia virus. The compounds investigated were lead chloride, N-acetyl-cystein(NAC), and Buthionine Sulfoximine(BSO). RESUJLTS: ATP synthesis in RAW 264.7 cells was unchanged by each lead concentration exposure in a dose dependent manner. The NO synthesis was decreased when exposed to lead(PbCl2) concentration 0.5 micro M. The presence of 300 micro M NAC, used as a pretreatment in the culture medium, caused the recovery of the lead induced decrease in NO synthesis, but in the presence of 300 micro M BSO as a pretreatment, there was no recoverey. Pretreatment with NAC and BSO had no affect on ATP synthesis at any of the lead concentrations used. CONCLUSIONS: These results indicated that GSH has a protective effect toward lead toxicity, and suggested that the inhibition of NO production in macrophage due to lead toxicity may be related to cofactors of iNOS (inducible nitric oxide synthase)
Abelson murine leukemia virus ; Acetylcysteine ; Adenosine Triphosphate ; Animals ; Buthionine Sulfoximine ; Glutathione* ; Macrophages ; Mice ; Nitric Oxide

OBJECTIVES: To evaluate the effect of glutathione(GSH) on lead induced modulation of nitric oxide(NO) synthesis, and to examine how lead modulates NO production in macrophages. METHODS: This study was observed in a culture of RAW 264.7 cells, which originated from a tumor in a Balb/c mouse that was induced by the Abelson murine leukemia virus. The compounds investigated were lead chloride, N-acetyl-cystein(NAC), and Buthionine Sulfoximine(BSO). RESUJLTS: ATP synthesis in RAW 264.7 cells was unchanged by each lead concentration exposure in a dose dependent manner. The NO synthesis was decreased when exposed to lead(PbCl2) concentration 0.5 micro M. The presence of 300 micro M NAC, used as a pretreatment in the culture medium, caused the recovery of the lead induced decrease in NO synthesis, but in the presence of 300 micro M BSO as a pretreatment, there was no recoverey. Pretreatment with NAC and BSO had no affect on ATP synthesis at any of the lead concentrations used. CONCLUSIONS: These results indicated that GSH has a protective effect toward lead toxicity, and suggested that the inhibition of NO production in macrophage due to lead toxicity may be related to cofactors of iNOS (inducible nitric oxide synthase)
Abelson murine leukemia virus ; Acetylcysteine ; Adenosine Triphosphate ; Animals ; Buthionine Sulfoximine ; Glutathione* ; Macrophages ; Mice ; Nitric Oxide

The Bcr-Abl oncogene is produced by the reciprocal translocation between c-Abl gene on chromosome 9 and the Bcr gene on chromosome 22 in human genome. The encoded Bcr-Abl fusion protein is responsible for the pathogenesis of certain human leukemias. Abelson murine leukemia virus (A-MuLV) is a retrovirus that could lead to transformation of B lymphocyte in mice, and v-Abl is the oncogene of A-MuLV. Abl oncoproteins (such as Bcr-Abl and v-Abl) play critical roles in tumorigenesis of certain cell types. Several signal transduction pathways, including JAK/STAT/Pim, PI3K/AKT/mTOR and RAS/RAF/MEK signaling pathway, are involved in Abl-mediated tumorigenesis. In addition, Abl-mediated tumorigenesis is associated with mutation or abnormal modification of key signal molecules as well as dysregulation of some critical long noncoding RNAs (lncRNAs). Here, we review the molecular mechanisms by which Abl oncogenes activate three major signaling pathways, and provide a scientific basis for therapy of Abl oncoprotein-induced tumors.
Abelson murine leukemia virus ; Animals ; Cell Transformation, Neoplastic ; Fusion Proteins, bcr-abl ; Genes, abl ; Humans ; Phosphatidylinositol 3-Kinases

Laboratory inbred mice are used widely and commonly in biomedical research, but inbred mice do not have a big enough gene pool for the research. In this study, genetic and morphometric analyses were performed to obtain data on the characteristics of a newly developing inbred strain (KWM/Hym) captured from Chuncheon, Korea. All of five Korean wild male mice have the zinc-finger Y (ZfY) gene. Also, all of 19 Korean wild mice used in this analysis have the AKV-type murine leukemia virus gene, indicating that Korean wild mice might be Mus musculus musculus. To identify the genetic polymorphism in KWM/Hym, SNP analysis was performed. In a comparison with 28 SNP markers, there was a considerable difference between KWM/Hym and several inbred strains. The homogeneity between KWM/Hym and the inbred strains was as follows: C57BL/6J (39.3%), BALB/c AJic (42.9%), and DBA/2J (50%). KWM/Hym is most similar to the PWK/PhJ inbred strain (96.4%) derived from wild mice (Czech Republic). To identify the morphometric characteristics of KWM/Hym, the external morphology was measured. The tail ratio of male and female was 79.60±3.09 and 73.55±6.14%, respectively. KWM/Hym has short and agouti-colored hairs and its belly is white with golden hair. Taking these results together, KWM/Hym, a newly developing inbred mouse originated from wild mouse, might be use as new genetic resources to overcome the limitations of the current laboratory mice.
Animals ; Female ; Gangwon-do* ; Gene Pool ; Hair ; Humans ; Korea* ; Leukemia Virus, Murine ; Male ; Mice* ; Polymorphism, Genetic ; Tail

For constructing pcDNA-ORF5, pcDNA-ORF5-ORF6, pcDNA-ORF5/6, the ORF5 and ORF6 of porcine reproductive and respiratory syndrome virus (PRRSV) were amplified by RT-PCR, and transiently transfected into 293T cells by calciumphosphate co-precipitation. After 48 h, 293T cells were collected and surveyed by flow cytometry examination. The result indicated that the expression level of the E protein that mediated by the M protein was higher than that of the E protein expressed independently. Then pcDNA-ORF5, pcDNA-ORF5-ORF6, pcDNA-ORF5/6 were respectivly co-transfected into 293T cells with pHIT60 (include MuLV structural genes,namely gag and pol) and pHIT111 (retroviral genome, containing LacZ as a reporter). The supernatants were harvested 48 h post-transfection,and the analysis of the characteristic of the pseudotyping virions was performed by Western blot and infection test. The result indicated that the E proteins were expressed on the virions, and incorporated into the retroviral virions. Infection test were performed on Marc-145 and PAM, all the cells infected were Lac Z positive. These results indicated the pseudotype virions of MuLV-E and MuLV-E/M were infectious, and higher infectivity was achieved by MuLV-E/M.
Flow Cytometry ; Leukemia Virus, Murine ; genetics ; Plasmids ; Porcine respiratory and reproductive syndrome virus ; genetics ; Viral Envelope Proteins ; genetics ; physiology ; Viral Matrix Proteins ; genetics ; physiology ; Virion ; genetics

The envelope (E) glycoprotein of JEV is the major antigen to elicit neutralizing antibody (NAb) against JEV infection. In order to develop a rapid and safe neutralization assay system for evaluation of the JEV vaccine strains, we constructed JEV-pseudotyped viruses with JEV env genes (Nakayama-NIH, Beijing-1). The titers of JEV-pseudotyped viruses with NK and BJ strains were 4.0x10(4) IFU/ml and 1.3x10(5) IFU/ml in Vero cell cultures, respectively. We have analyzed the neutralization activity of immunized mouse sera with JEV-NK and JEV-BJ pseudotyped viruses. The neutralizing antibody titers of NK and BJ (50% reduction of virus) were about 1:10,000 at each immunized sera. Compared with conventional plaque reduction neutralization test (PRNT), the method using JEV-pseudotyped virus has desirable advantages such as more rapid, easier, and non-biohazardous. This neutralization assay system might be useful to evaluate NAb activity against JEV vaccine strains or vaccine candidates.
Animals ; Antibodies, Neutralizing ; Asian Continental Ancestry Group* ; Encephalitis Virus, Japanese* ; Encephalitis, Japanese* ; Genes, env* ; Glycoproteins ; Humans ; Leukemia Virus, Murine* ; Mice ; Neutralization Tests ; Vero Cells

BACKGROUND: Xenotropic murine leukemia virus-related virus (XMRV) has been detected in peripheral blood mononuclear cells (PBMNs), therefore, it has been regarded as being infectious and transmittable by transfusion. Thus, we attempted to detect XMRV in blood samples in order to confirm the absence of XMRV from blood donors. METHODS: We achieved 165 blood donors and four chronic fatigue syndrome (CFS) patients. We performed real-time polymerase chain reaction using the LightCycler 480 (Roche, Penzberg, Germany) for the gag and env genes of the XMRV genome. DNA was extracted from peripheral blood samples. We used Uracil-N-Glycosylase in order to prevent contamination and DNA extracted from mouse embryonic fibroblasts (MEF) for amplification control. RESULTS: No XMRV was detected in any of the blood donors in both the gag and env genes. In four CFS patients, amplification was not detected in the gag gene. In two of four CFS patients, amplifications were detected and the melting temperature was in agreement with that of MEF control in the env gene. CONCLUSION: Although XMRV was not present in blood samples from blood donors, this is the first report on XMRV in Korean blood donors. We confirmed the absence of XMRV in Korean blood donors, the same as studies reported in other countries.
Animals ; Blood Donors ; DNA ; Fatigue Syndrome, Chronic ; Fibroblasts ; Freezing ; Genes, env ; Genes, gag ; Genome ; Humans ; Mice ; Real-Time Polymerase Chain Reaction ; Xenotropic murine leukemia virus-related virus

To produce the reverse transcriptase of moloney murine leukemia virus (MMLV-RT) through gene recombination, MMLV-rt gene was amplified by polymerase chain reaction (PCR) with specifically designed primers bearing restriction enzyme sites. Five mutation sites increasing the solution of the target protein were introduced through Site-directed mutation. After verification by sequencing, the gene was cloned into the expression vector pET15b to construct the recombinant plasmid pET15b-MMLV-rt. Purified MMLV-RT was obtained by affinity chromatography (Ni3+-NTA beads). Molecular weight and purity of MMLV-RT were analyzed with SDS-PAGE. Enzyme activity was characterized with RT-PCR. We successfully constructed the recombinant plasmid pET15b-MMLV-rt and obtained the MMLV-RT fusion protein with 6His on the N-terminus. Recombinant protein was purified through Ni3+-NTA beads based affinity chromatography, the purity of which was 96%. The Activity of the enzyme was high. MMLV-RT of 96% purity was obtained with the prokaryotic expression technique, which serves as the basis for mass production of this enzyme.
Animals ; Mice ; Moloney murine leukemia virus ; enzymology ; genetics ; RNA-Directed DNA Polymerase ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; metabolism ; Recombination, Genetic

OBJECTIVES: The nickel and cobalt present in many industrial working environments and consumer products. They are two of the leading causes of allergic contact dermatitis, which is a typical delayed(type IV) hypersensitivity reaction. However, the mechanism by which nickel and cobalt causes this pathology is not well known. The nickel and cobalt induced contact dermatitis is mediated primarily through macrophages. This mechanism is similar to the autotoxicity procedure for NO. Therefore, this study was designed to examine whether the metals could modulate NO production and how the metals may affect ATP production and cell viability. In summary, the purpose of this study was to elucidate the role of NO in the nickel and cobalt induced cytotoxicity. METHODS: This study is based on observations of cultures of RAW 264.7 cells which are originated from a tumor of Balb/c mouse that was induced by Abelson murine leukemia virus. RAW 264.7 cells were treated with either Ni, Co, Ni plus Co, or Nmonomethyl-L- arginine(NMLA) for 24-72 h. The cytotoxicity of the nickel and cobalt was measured by cell viability and NO2-, and mitochondrial function was evaluated by adenosine triphosphate(ATP) production in RAW 264.7 cells. In addition, the morphology of cells was observed using an inverted microsope. RESULTS: The NO2- synthesis of RAW 264.7 cells increased with increasing concentrations of Ni and Co up to 50 microM after 24 and 48 h of exposure to Ni and Co but then decreased if the concentration was greater than 50 microM and the time period was greater than 48 h. However, the viability of cells was decreased by Ni and Co exposure in a dose and time dependent manner. Therefore, 50 microM Ni or Co and 48 h of treatment were used in this study. A complete inhibition of NO2- synthesis by Ni or/and Co occurred when iNOS inhibitor, NMLA, were pretreated prior to addition of Ni or/and Co, whereas Ni or/and Co induced decrease of synthesis of ATP and viability completely recovered when NMLA were pretreated prior to addition of Ni or/and Co. Ni or/and Co(50 microM) induced the characteristic morphological features of cytotoxicity which is characterized by a shrinkage of cytoplasm and irregular shape of the cells, but the pretreatment of NMLA resulted in a recovered morphological change of the cells to their normal appearance. CONCLUSIONS: These results suggest that NO plays an important role in the pathogenesis of the cytotoxicity of nickel and cobalt, and nickel and cobalt may exert their toxicities by means of modulation of NO production. The results from this study may facilitate further understanding the role of NO on nickel and cobalt induced immune and inflammatory processes.
Abelson murine leukemia virus ; Adenosine ; Adenosine Triphosphate ; Animals ; Cell Survival ; Cobalt* ; Cytoplasm ; Dermatitis, Allergic Contact ; Dermatitis, Contact ; Hypersensitivity ; Macrophages ; Metals ; Mice ; Nickel* ; Nitric Oxide* ; Pathology