Efficient in vitro expression of interferon alpha analogs using SP6 polymerase and rabbit reticulocyte lysate.

We have investigated the use of in vitro expression as a quick and convenient means of screening large numbers of interferon (IFN) analogs generated using in vitro mutagenesis. The IFN-alpha 1 mRNA generated from DNA template using SP6 RNA polymerase is efficiently translated in rabbit reticulocyte lysate (RRL). The antiviral specific activity of this RRL-synthesized IFN-alpha l is equivalent to the yeast-synthesized protein. In contrast with the yeast-expression system, where some IFN-alpha analogs are poorly expressed, all analogs tested were well expressed in RRL.