Retroviruses are efficient tools for delivering heritable genes into the genome of dividing cells. Moloney Murine Leukemia Virus (MMLV)-based retroviral vector system is the most commonly used gene transfer vehicle. pCMV-Gag-Pol expresses the retroviral structure proteins under the control of the CMV immediate-early promoter. The gag region encodes genes which comprise the capsid proteins; the pol region encodes the reverse transcriptase and integrase proteins.
Retrovirus can be produced using one of the following methods:
1) Transfection of a retrovirus packaging cell line with a retrovirus expression vector. Packaging cell lines usually stably express gag, pol and env genes. For example, transfection of Plat-E packaging cell line (
MBS169333 ) with a pMXs vector would produce an ecotropic retrovirus.
2) Cotransfection of a host cell with plasmids containing LTRs, Gag, Pol, Env. For example, cotransfection of 293RTV (
MBS169332) with pMXs, pCMV-Gag-Pol (
MBS168500) and pCMV-VSV-G (
MBS168028) would produce VSVG-pseudotyped retrovirus.
Note: We recommend cotransfection of expression vector:gag-pol vector: envelope vector at the following plasmid ratios:
(a) For ecotropic or amphotropic retrovirus, 3:1:1
(b) For VSVG-pseudotyped retrovirus, 3:1:0.5
