pDsRed2-ER is a mammalian expression vector that encodes a fusion consisting of Discosoma sp. red fluorescent protein (DsRed2); the endoplasmic reticulum (ER) targeting sequence of calreticulin, fused to the 5′ end of DsRed2; and the ER retention sequence, KDEL, fused to the 3′ end of DsRed2a human codon-optimized DsRed variant engineered for faster maturation and lower non-specific aggregation.
To drive expression of DsRed2, this vector contains the immediate early promoter of cytomegalovirus (PCMV IE). SV40 polyadenylation signals downstream of the DsRed2 gene direct proper processing of the 3′-end of the DsRed2 mRNA transcript. The vector also contains an SV40 origin for replication in any mammalian cell line that expresses the SV40 T-antigen, a pUC origin of replication for propagation in E. coli, and an f1 origin for single-stranded DNA production. A neomycin resistance cassetteconsisting of the SV40 early promoter (PSV40e), the neomycin/kanamycin resistance gene of Tn5 (Neor/Kanr), and polyadenylation signals from the herpes simplex virus thymidine kinase (HSV TK poly A) geneallows stably transfected eukaryotic cells to be selected using G418. A bacterial promoter (P) upstream of this cassette drives expression of the gene encoding kanamycin resistance in E. coli.