scholarly journals Second site mutation in the virus envelope expands the host range of a cytopathic variant of Moloney murine leukemia virus

Virology ◽  
2012 ◽  
Vol 433 (1) ◽  
pp. 7-11 ◽  
Author(s):  
John Ferrarone ◽  
Ryan C. Knoper ◽  
Randolph Li ◽  
Christine A. Kozak
Keyword(s):  
Host Range ◽  
Murine Leukemia Virus ◽  
Leukemia Virus ◽  
Moloney Murine Leukemia Virus ◽  
Site Mutation ◽  
Virus Envelope ◽  
Murine Leukemia

scholarly journals Sequential activation of the three protomers in the Moloney murine leukemia virus Env

2017 ◽  
Vol 114 (10) ◽  
pp. 2723-2728 ◽  
Author(s):  
Mathilda Sjöberg ◽  
Robin Löving ◽  
Birgitta Lindqvist ◽  
Henrik Garoff
Keyword(s):  
Murine Leukemia Virus ◽  
Leukemia Virus ◽  
Moloney Murine Leukemia Virus ◽  
Virus Envelope ◽  
Sequential Activation ◽  
Virus Envelope Protein ◽  
Membrane Fusion Proteins ◽  
Viral Membrane Fusion ◽  
Murine Leukemia

Viral membrane fusion proteins of class I are trimers in which the protomeric unit is a complex of a surface subunit (SU) and a fusion active transmembrane subunit (TM). Here we have studied how the protomeric units of Moloney murine leukemia virus envelope protein (Env) are activated in relation to each other, sequentially or simultaneously. We followed the isomerization of the SU-TM disulfide and subsequent SU release from Env with biochemical methods and found that this early activation step occurred sequentially in the three protomers, generating two asymmetric oligomer intermediates according to the scheme (SU-TM)3→ (SU-TM)2TM → (SU-TM)TM2→ TM3. This was the case both when activation was triggered in vitro by depleting stabilizing Ca2+from solubilized Env and when viral Env was receptor triggered on rat XC cells. In the latter case, the activation reaction was too fast for direct observation of the intermediates, but they could be caught by alkylation of the isomerization active thiol.

scholarly journals Pseudotype Formation of Moloney Murine Leukemia Virus with Sendai Virus Glycoprotein F

1998 ◽  
Vol 72 (6) ◽  
pp. 5296-5302 ◽  
Author(s):  
Martin Spiegel ◽  
Michael Bitzer ◽  
Andrea Schenk ◽  
Heidi Rossmann ◽  
Wolfgang J. Neubert ◽  
...  
Keyword(s):  
Host Range ◽  
Murine Leukemia Virus ◽  
Sendai Virus ◽  
Mdck Cells ◽  
Leukemia Virus ◽  
Direct Proof ◽  
Hepatoma Cells ◽  
The Other ◽  
Moloney Murine Leukemia Virus ◽  
Murine Leukemia

ABSTRACT Mixed infection of cells with both Moloney murine leukemia virus (MoMLV) and related or heterologous viruses produces progeny pseudotype virions bearing the MoMLV genome encapsulated by the envelope of the other virus. In this study, pseudotype formation between MoMLV and the prototype parainfluenza virus Sendai virus (SV) was investigated. We report for the first time that SV infection of MoMLV producer cells results in the formation of MoMLV(SV) pseudotypes, which display a largely extended host range compared to that of MoMLV particles. This could be associated with SV hemagglutinin-neuraminidase (SV-HN) glycoprotein incorporation into MoMLV envelopes. In contrast, solitary incorporation of the other SV glycoprotein, SV fusion protein (SV-F), resulted in a distinct and narrow extension of the MoMLV host range to asialoglycoprotein receptor (ASGP-R)-positive cells (e.g., cultured human hepatoma cells). Since stably ASGP-R cDNA-transfected MDCK cells, but not parental ASGP-R-negative MDCK cells, were found to be transduced by MoMLV(SV-F) pseudotypes and transduction of ASGP-R-expressing cells was found to be inhibited by ASGP-R antiserum, a direct proof for the ASGP-R-restricted tropism of MoMLV(SV-F) pseudotypes was provided. Cultivation of ASGP-R-positive HepG2 hepatoma cells on Transwell-COL membranes led to a significant enhancement of MoMLV(SV-F) titers in subsequent flowthrough transduction experiments, thereby suggesting the importance of ASGP-R accessibility at the basolateral domain for MoMLV(SV-F) pseudotype transduction. The availability of such ASGP-R-restricted MoMLV(SV-F)-pseudotyped vectors opens up new perspectives for future liver-restricted therapeutic gene transfer applications.

scholarly journals Role of intron-contained sequences in formation of moloney murine leukemia virus env mRNA.

1984 ◽  
Vol 4 (11) ◽  
pp. 2289-2297 ◽  
Author(s):  
L S Hwang ◽  
J Park ◽  
E Gilboa
Keyword(s):  
Splice Site ◽  
Murine Leukemia Virus ◽  
Leukemia Virus ◽  
Splice Junction ◽  
Moloney Murine Leukemia Virus ◽  
Expression Vectors ◽  
Virus Envelope ◽  
Cellular Genes ◽  
Murine Leukemia

Formation of the Moloney murine leukemia virus envelope mRNA involves the removal of a 5,185-base pair-long intron. Deletion analysis of two Moloney murine leukemia virus-derived expression vectors revealed the existence of two short regions within the viral intron which are required for the efficient formation of the spliced RNA species. One region was present upstream from the 3' splice junction, extended at least 85 nucleotides beyond the splice site, and was not more than 165 nucleotides long. As yeast polymerase II introns, the Moloney murine leukemia virus intron contains the sequence 5'-TACTAAC-3' 15 nucleotides upstream from the 3' splice site. A second region located in the middle of the intron, within a 560-nucleotide-long sequence, was also essential for formation of the spliced RNA species. The efficient splicing of the env mRNA in the absence of expression of viral genes raises the possibility that similar mechanisms are used to remove introns of (some) cellular genes.

scholarly journals Moloney Murine Leukemia Virus Envelope Protein Subunits, gp70 and Pr15E, Form a Stable Disulfide-Linked Complex

1998 ◽  
Vol 72 (8) ◽  
pp. 6537-6545 ◽  
Author(s):  
Dirk-Jan E. Opstelten ◽  
Michael Wallin ◽  
Henrik Garoff
Keyword(s):  
Murine Leukemia Virus ◽  
Leukemia Virus ◽  
Alkylating Agents ◽  
Moloney Murine Leukemia Virus ◽  
Virus Envelope ◽  
Disulfide Linkage ◽  
Virus Envelope Protein ◽  
Biochemical Analyses ◽  
Murine Leukemia

ABSTRACT The nature and stability of the interactions between the gp70 and Pr15E/p15E molecules of murine leukemia virus (MLV) have been disputed extensively. To resolve this controversy, we have performed quantitative biochemical analyses on gp70-Pr15E complexes formed after independent expression of the amphotropic and ecotropic Moloney MLVenv genes in BHK-21 cells. We found that all cell-associated gp70 molecules are disulfide linked to Pr15E whereas only a small amount of free gp70 is released by the cells. The complexes were resistant to treatment with reducing agents in vivo, indicating that the presence and stability of the disulfide interaction between gp70 and Pr15E are not dependent on the cellular redox state. However, disulfide-bonded Env complexes were disrupted in lysates of nonalkylated cells in a time-, temperature-, and pH-dependent fashion. Disruption seemed not to be caused by a cellular factor but is probably due to a thiol-disulfide exchange reaction occurring within the Env complex after solubilization. The possibility that alkylating agents induce the formation of the intersubunit disulfide linkage was excluded by showing that disulfide-linked gp70-Pr15E complexes exist in freshly made lysates of nonalkylated cells and that disruption of the complexes can be prevented by lowering the pH. Together, these data establish that gp70 and Pr15E form a stable disulfide-linked complex in vivo.

Role of intron-contained sequences in formation of moloney murine leukemia virus env mRNA

1984 ◽  
Vol 4 (11) ◽  
pp. 2289-2297
Author(s):  
L S Hwang ◽  
J Park ◽  
E Gilboa
Keyword(s):  
Splice Site ◽  
Murine Leukemia Virus ◽  
Leukemia Virus ◽  
Splice Junction ◽  
Moloney Murine Leukemia Virus ◽  
Expression Vectors ◽  
Virus Envelope ◽  
Cellular Genes ◽  
Murine Leukemia

Formation of the Moloney murine leukemia virus envelope mRNA involves the removal of a 5,185-base pair-long intron. Deletion analysis of two Moloney murine leukemia virus-derived expression vectors revealed the existence of two short regions within the viral intron which are required for the efficient formation of the spliced RNA species. One region was present upstream from the 3' splice junction, extended at least 85 nucleotides beyond the splice site, and was not more than 165 nucleotides long. As yeast polymerase II introns, the Moloney murine leukemia virus intron contains the sequence 5'-TACTAAC-3' 15 nucleotides upstream from the 3' splice site. A second region located in the middle of the intron, within a 560-nucleotide-long sequence, was also essential for formation of the spliced RNA species. The efficient splicing of the env mRNA in the absence of expression of viral genes raises the possibility that similar mechanisms are used to remove introns of (some) cellular genes.

Sign in / Sign up

Export Citation Format

Share Document