MOLECULAR-DETECTION AND IDENTIFICATION OF TYPE-I INTERFERON MESSENGER-RNAS

The development of a technique for identifying murine type I interfero n messenger RNAs is described that involves the following essential st eps: (a) the reverse transcription of total RNA extracts using oligo(d T)(12-18) as a primer, (b) the amplification of any type I interferon cDNAs produced by polymerase chain reaction, and (c) the identificatio n of interferon subtypes by hybridization of the polymerase chain reac tion products to specific oligonucleotides. The technique was used to characterize the expression of the mouse interferon subtypes al, alpha 4, alpha 5, alpha 6, and beta in murine L929 cells that had been infe cted with Newcastle disease virus. The data derived from this study ar e in excellent agreement with earlier RNA protection experiments perfo rmed in the same system to characterize expression of the same genes. The present technique has advantages over those used previously, inclu ding superior sensitivity, speed, and far smaller input RNA requiremen ts. The technique is not only applicable to other in vitro systems, bu t is appropriate for use in vivo.