A. Flint et al., Co-transfected SV40 origin of replication activates expression from SV40 promoterless constructs, BIOTECHNIQU, 27(4), 1999, pp. 728-732
Co-transfection with expression plasmids is widely used ta control DNA upta
ke efficiency in transient transfection experiments. However in number of p
roblems have bren associated with their use. Here, we describe the activati
on of expression of constructs not containing the simian virus 40 (SV40) or
igin of replication (ori) by cotransfection in COS-7 cells with plasmids co
ntaining the SV40 ori. This effect has consequences for the use of such pla
smids to control transfection efficiency.