Cryptic polyadenylation of transcripts of an RNA virus gene introduced into tobacco plants

Abstract

We constructed an expression vector for the coat protein (CP) gene and the 3′ untranslated region (3′ UTR) of RNA virus (sweet potato feathery mottle virus severe strain (SPFMV-S)) lacking a foreign terminator. Out of seven transgenic tobacco plants, expression of the transgene was observed in six plants. RT-PCR analysis revealed that the transcripts had a poly(A) tail, and in most of them, polyadenylation occurred on the 5′ side of the 3′ UTR. These results suggest that the viral sequence contains a cryptic polyadenylation signal that permits 3′-end processing of the transcripts.