Learn how to use this product The pESG-IBA142 vector is a mammalian expression vector designed for high-level, stable, and non-replicative transient expression of target proteins with an N-terminal His-tag and C-terminal Twin-Strep-tag® in mammalian cells. The vector carries an ampicillin resistance cassette for the selection of transformed E. coli cells and the F1 and ColE1 origin for a high plasmid copy number. In addition, it carries the human cytomegalovirus (CMV) immediate-early promoter for high-level expression in a wide range of mammalian cells, the neomycin resistance gene for selection of stable cell lines, and the SV40 ori for episomal replication in cell lines that are latently infected with SV40 or that express the SV40 large T antigen such as HEK293T, COS-1, and COS-7. BM40 secretory signal peptide is encoded for the transfer of the expressed protein into the medium. During translocation from the cytosol, the signal peptide is removed from the protein by endogenous proteases. It should be noted that cloning into pESG-IBA Acceptor Vectors compulsorily requires the restriction enzyme Esp3I since no other MCS for the integration of a gene of interest is available. In addition to the direct cloning of the gene of interest into pESG-IBA vectors with Esp3I, another option via a so-called Entry Vector is possible.