Translational in vitro activity of the 3a gene and the coat protein gene derived from brome mosaic virus RNA 3 by site-specific cleavage with RNase H

AbstractTwo translationally active fragments were derived from the dicistronic Brome Mosaic Virus (BMV) RNA 3 by site-specific cleavage with RNase H from E.coli: the 5′-proximal (L)fragment encoding the 32 kDa protein and the 3′-proximal (Sh) fragment carrying the coat protein gene. The translational efficiency of the L- and Sh-fragments was compared with those of the native BMV RNA 3 and RNA 4, encoding the 32 kDa and coat proteins, respectively. The Sh-fragment template activity was similar to that of RNA 4, although it was uncapped and contained 20–22 additional 5′-terminal nucleotides in comparison with BMV RNA 4

Translation enhancing properties of the 5′-leader of potato virus X genomic RNA

AbstractThe double-stranded DNA copy corresponding to the 5′-nontranslated αβ-leader of potato virus X (PVX) genomic RNA (positions −3 to −85 according to AUG initiator) was chemically synthesized and fused to the transcription plasmids containing three different reporter genes: neomycinphosphotransferase type II (NPT II) gene, Bacillus thuringiensis coleopteran-specific toxic protein gene and β-glucuronidase (GUS) gene. Expression of the reporter genes in vitro and in plant protoplasts (in the case of GUS gene) reveals that the αβ-leader of PVX RNA acts as a translation enhancer despite the presence of the upstream vector-derived sequence and irrespective of the length of the spacer sequence preceding the reporter genes