Abstract
Many retroviral vectors based on murine leukaemia virus (MLV) contain the first 420 nucleotides of the gag gene, as this was reported to increase vector titre by increasing the efficiency of RNA packaging. In this study, deletion of this gag sequence from its original location did not decrease the titre of two retroviral vectors, pBabe puro and MFG-S−. The two vectors could be improved by replacing the gag sequence with a CTE from Mason–Pfizer monkey virus (MPMV). This substitution improved vector titre, while eliminating a region of homology between vector and packaging constructs.
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References
Anderson WF . Human gene therapy Nature 1998 392: 25–30
Armentano D et al. Effect of internal viral sequences on the utility of retroviral vectors J Virol 1987 61: 1647–1650
Bender MA, Palmer TD, Gelinas RE, Miller AD . Evidence that the packaging signal of Moloney murine leukaemia virus extends into the gag region J Virol 1987 61: 1639–1646
Adam MA, Miller AD . Identification of a signal in a murine retrovirus that is sufficient for packaging of nonretroviral RNA into virions J Virol 1988 62: 3802–3806
Fischer U et al. Evidence that HIV-1 Rev directly promotes the nuclear export of unspliced RNA EMBO J 1994 13: 4105–4112
Nasioulas G et al. Elements distinct from human immunodeficiency virus type 1 splice sites are responsible for the Rev dependence of env mRNA J Virol 1994 68: 2986–2993
Bray M et al. A small element from the Mason–Pfizer monkey virus genome makes human immunodeficiency virus type 1 expression and replication Rev-independent Proc Natl Acad Sci USA 1994 91: 1256–1260
Ernst RK, Bray M, Rekosh D, Hammarskjold ML . A structured retroviral RNA element that mediates nucleocytoplasmic export of intron-containing RNA Mol Cell Biol 1997 17: 135–144
Ogert RA, Lee LH, Karen LB . Avian retroviral RNA element promotes unspliced RNA accumulation in the cytoplasm J Virol 1996 70: 3834–3843
Zolotukhin AS, Valentin A, Pavlakis GN, Felber BK . Continuous propagation of RRE(−) and Rev(−) RRE(−) human immunodeficiency virus type 1 molecular clones containing a cis-acting element of simian retrovirus type 1 in human peripheral blood lymphocytes J Virol 1994 68: 7944–7952
Pasquinelli AE et al. The CTE of MPMV accesses a cellular mRNA export pathway EMBO J 1997 16: 7500–7510
Saavedra C, Felber BK, Izaurralde E . The simian retrovirus-1 constitutive transport element, unlike the HIV-1 RRE, uses factors required for cellular mRNA export Curr Biol 1997 7: 619–628
Tang H et al. A cellular cofactor for the constitutive transport element of type D retrovirus Science 1997 276: 1412–1415
Tabernero C et al. Identification of an RNA sequence within an intracisternal-A particle element able to replace Rev-mediated postranscriptional regulation of human immunodeficiency virus type 1 J Virol 1997 71: 95–101
von Gegerfelt A, Felber BK . Replacement of post-transcriptional regulation in SIVmac239 generated a Rev-independent infectious virus able to propagate in rhesus peripheral blood mononuclear cells Virology 1997 232: 291–299
Morgenstern JP, Land H . Advanced mammalian gene transfer: high titre retroviral vectors with multiple drug selection markers and a complementary helper-free packaging cell line Nucleic Acids Res 1992 18: 3587–3596
Kim SH et al. Construction of retroviral vectors with improved safety, gene expression, and versatility J Virol 1998 72: 994–1004
Rizvi TA, Lew KA, Murphy EC Jr . Schmidt RD. Role of MPMV CTE in the propagation of MPMV vectors by genetic complementation using homologous/heterologous env genes Virol 1996 224: 517–532
Cosset F-L et al. Higher-titre packaging cells producing recombinant retroviruses resistant to human serum J Virol 1995 69: 7430–7436
Danos O, Mulligan RC . Safe and efficient generation of recombinant retroviruses with amphotropic and ecotropic host range Proc Natl Acad Sci USA 1988 85: 3539–3543
Soneoka Y et al. A transient three-plasmid expression system for the production of high titre retroviral vectors Nucleic Acids Res 1995 23: 628–633
King J et al. The extended packaging sequence of MoMLV contains a constitutive mRNA nuclear export function FEBS Lett 1998 434: 367–371
Prats A et al. Cis elements and transacting factors involved in dimmer formation of murine leukaemia virus RNA J Virol 1990 64: 774–783
Berlioz C, Darlix J-L . An internal ribosomal entry mechanism promotes translation of MLV gag polyprotein precursors J Virol 1995 69: 2214–2222
Pear W . Nolan G, Scott M, Baltimore D. Production of high titre helper-free retroviruses by transient transfection Proc Natl Acad Sci USA 1993 90: 8392–8396
Brody BA, Rhee SS, Hunter E . Postassembly cleavage of a retroviral glycoprotein cytoplasmic domain removes a necessary incorporation signal and activates fusion activity J Virol 1994 68: 4620–4627
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This study was supported by an MRC Programme Grant, number G9314271.
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Zhao, Y., Low, W. & Collins, M. Improved safety and titre of murine leukaemia virus (MLV)-based retroviral vectors. Gene Ther 7, 300–305 (2000). https://doi.org/10.1038/sj.gt.3301081
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DOI: https://doi.org/10.1038/sj.gt.3301081
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