Schematic of a typical recombination reaction in the Creator Splice system. The SD/intron, shown in purple, is the only difference between a Creator Splice acceptor and a standard acceptor vector. A Creator Splice donor and acceptor are recombined in the presence of Cre recombinase in vitro. An intron is formed in the resulting expression vector starting from the SD/intron supplied by the acceptor and ending with the splice acceptor from the donor vector. Upon transfection and transcription in mammalian cells, the intron is removed and the tag is juxtaposed onto the ORF. Abbreviations: bac – bacteria promoter, CmR – Chloramphenicol resistance ORF, kan/neoR – kanamycin and neomycin resistance gene, P – promoter, SA – splice acceptor, SD – splice donor.