The pBudCE4.1 vector is designed for the independent expression of two genes from a single plasmid in mammalian cells. Using pBudCE4.1 to generate stable mammalian expression cell lines ensures that there is an equivalent copy number of each gene in the cell. This can eliminate variable expression due to differences in gene copy number. pBudCE4.1 provides expression cassettes withthe following features:

The CMV promoter for high-level transcription of genes with an optional c-myc epitope tag for rapid detection and 6xHis sequence for simple purification

• The human EF-1α promoter for high-level expression of genes with an optional V5 epitope tag for rapid detection and 6xHis sequence for simple purification
• The Sh ble (ZeoR) gene for efficient selection in both mammalian cells and E. coliwith the selection agent Zeocin™