FAQ: Does transcription with SP6 RNA Polymerase require a primer?

No. Unlike DNA polymerases, no primers are needed for the activity of SP6 RNA Polymerase. The SP6 promoter region must be double-stranded in order for the polymerase to recognize the promoter sequence with transcription starting at the final G. The polymerase then transcribes using the opposite strand as the template from 5´ to 3´. Linearized plasmids, PCR products or synthetic DNA oligonucleotides annealed to a short, SP6 promoter-containing oligonucleotide can all serve as templates for in vitro transcription with SP6 RNA Polymerase.