The pSV-Beta-Galactosidase Control Vector is a positive control vector for monitoring transfection efficiencies of mammalian cells. The SV40 early promoter and enhancer drive transcription of the lacZ gene, which encodes the beta-galactosidase enzyme. The pSV-Beta-Galactosidase Control Vector can be transfected individually or co-transfected with your DNA of interest. Beta-galactosidase is an excellent reporter enzyme that can be assayed quickly and directly in cell extracts using spectrophotometric, fluorescent or chemiluminescent assays. This reporter enzyme also is widely used for in situ histochemical analysis using the substrate X-Gal. The pSV-Beta-Galactosidase Control Vector can be co-transfected with your DNA of interest. For example, co-transfection with firefly luciferase gene vectors (pGL3 Vectors) provide cell extracts that can be assayed for both luciferase and beta-galactosidase activities. In this manner, the pSV-Beta-Galactosidase Vector acts as an internal control for transient expression assays. A negative control extract, prepared from mock-transfected cells, should also be assayed for the presence of endogenous beta-galactosidase activity in cultured cells. In addition, co-transfection with chloramphenicol acetyltransferase reporter gene vectors (pCAT3 Vectors) permits assaying for both CAT and beta-galactosidase activities. The pSV-Beta-Galactosidase Vector is a modification of pRSV-beta-Gal with SV40 and pUC18 sequences substituted for RSV and pBR322 sequences. The pSV-Beta-Galactosidase Vector will express beta-galactosidase in E. coli due to the presence of the E. coli gpt promoter located upstream of the lacZ gene. Colonies of E. coli containing the pSV-Beta-Galactosidase Vector will appear blue when plated on media containing X-Gal.|