Disease relevance of Mason-Pfizer Monkey Virus

• Here we show that a cis-acting 219-nucleotide sequence from an unrelated "simple" retrovirus, Mason-Pfizer monkey virus (MPMV), enables Rev-independent HIV-1 replication [1].
• By developing an antibody against the prototype betaretrovirus Mason-Pfizer monkey virus dUTPase, we demonstrate that i) the NC-dUTPase fusion protein exists both within the virions and infected cells providing the only form of dUTPase, and ii) the retroviral protease does not cleave NC-dUTPase either in the virion or in vitro [2].
• Viral protease-mediated cleavage within the cytoplasmic domain of the transmembrane (TM) glycoprotein of the type D retrovirus, Mason-Pfizer monkey virus, removes approximately 16 amino acids from the carboxy terminus of the protein [3].
• The gag precursor polyprotein was also labeled in mouse mammary tumor virus and in Mason-Pfizer monkey virus, but Pr76gag of Rous sarcoma virus failed to incorporate [3H]myristate [4].
• Other retroviruses, including simian immunodeficiency virus, equine infectious anemia virus, bovine leukemia virus, Moloney murine leukemia virus, mouse mammary tumor virus, and Mason-Pfizer monkey virus, were found to contain amounts of zinc per milligram of total protein similar to those found in HIV-1 and HTLV-I [5].

High impact information on Mason-Pfizer Monkey Virus

• A viral protease-mediated cleavage of the transmembrane glycoprotein of Mason-Pfizer monkey virus can be suppressed by mutations within the matrix protein [6].
• A mutation within the active site of the Mason-Pfizer monkey virus aspartyl protease was shown to block both TM glycoprotein cleavage and the processing of the Gag polyprotein precursor [6].
• Here we show that the genome of the simpler retrovirus Mason-Pfizer monkey virus (MPMV) contains an element that serves as an autonomous nuclear export signal for intron-containing RNA [7].
• We have recently demonstrated that amino acid substitutions of a tyrosine residue in the cytoplasmic domain block glycoprotein incorporation into budding Mason-Pfizer monkey virus (M-PMV) particles and abrogate infectivity (C. Song, S. R. Dubay, and E. Hunter, J. Virol. 77:5192-5200, 2003) [8].
• The retrovirus Mason-Pfizer monkey virus (MPMV) carries closely spaced PPPY and PSAP motifs [9].

Chemical compound and disease context of Mason-Pfizer Monkey Virus

• The effect of the monovalent carboxylic ionophore monensin on the biosynthesis, intracellular transport, and surface expression of the glycoproteins of Mason-Pfizer monkey virus was examined [10].
• Effect of tunicamycin on cell fusion induced by Mason-Pfizer monkey virus [11].
• Myristic acid is normally esterified through an amide linkage to a glycine residue at the amino terminus of the Mason-Pfizer monkey virus gag gene products [12].
• In contrast to the inhibition of EIAV Rev and FIV Rev, the cytoplasmic accumulation of hepatitis B virus (HBV) posttranscriptional regulatory element (PRE)-containing and Mason-Pfizer monkey virus (MPMV) constitutive transport element (CTE)-containing RNAs is not inhibited by leptomycin B treatment [13].
• Development of SRV-2 viraemia, infection with simian immunodeficiency virus or administration of cyclosporin A could result in persistent RFHVMm viraemia [14].

Biological context of Mason-Pfizer Monkey Virus

• Treatment of rhesus monkey fetal lung cells with different concentrations of tunicamycin, a potent inhibitor of glycosylation, during infection with Mason-Pfizer monkey virus had no effect on cell fusion even though up to 5 micrograms of the drug per ml was tested [11].
• Mutations within the env gene of Mason-Pfizer monkey virus: effects on protein transport and SU-TM association [15].
• By deletion mutagenesis analyses, we have examined the contribution of the immunosuppressive peptide (ISP) region within the transmembrane (TM) protein of Mason-Pfizer monkey virus to viral maturation and infectivity [15].
• No nucleic acid sequence homology between GPV RNA and the viral RNAs of the MMTV, murine leukemia virus, hamster sarcoma virus, or Mason-Pfizer monkey virus could be observed in a competition hybridization assay using the radioactive-labeled GPV 60 to 70S RNA [16].
• Neuraminidase treatment of mouse mammary tumor virus, Rauscher murine leukemia virus, and Mason-Pfizer monkey virus resulted in loss of their capacity to inhibit hemagglutination of influenza virus [17].

Anatomical context of Mason-Pfizer Monkey Virus

• The Rev-independent cell lines were created by using gag-pol and env expression vectors that contain the Mason-Pfizer monkey virus (MPMV) constitutive transport element (CTE) [18].
• The capsids of Mason-Pfizer monkey virus (M-PMV), an immunosuppressive type D retrovirus, are preassembled in the infected cell cytoplasm and are then transported to the plasma membrane, where they are enveloped in a virus glycoprotein-containing lipid bilayer [19].
• Production of soluble surface glycoprotein, GP70, of the Mason-Pfizer monkey virus in COS cells is dependent on the presence of regions of the transmembrane domain [20].
• Characterization of T cell epitopes on the envelope glycoprotein of simian retrovirus 1 and 2 (SRV-1 and SRV-2) in several mouse strains [21].

Gene context of Mason-Pfizer Monkey Virus

• In this study, we demonstrate that the Rev regulation of SIVmac239 can be replaced by the presence of the cis-acting transport element (CTE) of the type D simian retroviruses 1 (SRV-1) [22].
• In RF cells, SRV-2 functions to increase IL-6 mRNA and protein production and presumably serves as autocrine growth factor [23].
• Further studies are required to determine the relationship between the interaction of bFGF, SRV-2, and VEGF [24].
• We report here that the TM glycoprotein of Mason-Pfizer monkey virus undergoes a second proteolytic processing event during a late maturation step that can follow virus release and Gag polyprotein cleavage [6].
• Provirus and RNA virus loads were obtained, the samples were screened for presence of antibodies to SRV-2 and neutralizing antibody titers to SRV-2 were assayed. env sequences were aligned to determine intra- and intermonkey variation over time [25].

Analytical, diagnostic and therapeutic context of Mason-Pfizer Monkey Virus

• Preliminary sequence analysis of two separate isolates from portions of the SRV-Pc p27 and gp20 regions revealed homology with SRV-1, SRV-2, and Mason-Pfizer monkey virus [26].
• Sera from 526 old-world primates representing 50 different species were screened by ELISA for antibodies to human T-lymphotropic viruses I and III, and simian retrovirus type 1 (SRV-1) [27].
• PMFV, a type D retrovirus isolated from a malignant human embryo cell line, was compared with Mason-Pfizer monkey virus (MPMV) in a sensitive tannic acid enhanced indirect immunodiffusion test [28].
• The data from flow cytometry demonstrated the co-existence of SRV-2 and bFGF among RF cells and RF tissues [24].
• The SRV-2 membrane antigen contains the major proteins detected in positive sera by Western blotting: env proteins gp70 and gp20 and gag proteins p27, p14, p12, and p10 [29].

References