EXPRESSION OF RNA TRANSCRIPTS OF POTATO VIRUS-X FULL-LENGTH AND SUBGENOMIC CDNAS

Translation of synthetic potato virus X (PVX) RNAs was examined in Krebs II ascite cell extracts and rabbit reticulocyte lysates. Either full-length or subgenomic RNAs produced by in vitro transcription on cDNAs cloned in the T7 promoter vectors were used. Full-length PVX RNA-transcript directed the synthesis of a large polypeptide which was indistingushable from the translation product (165 kDa) of authentic viral genomic RNA on SDS-PAGE. Translation of the full-length and 3′-truncated RNA species was stimulated by addition of m7GpppG to the T7 transcription system. Subgenomic cDNA transcripts corresponding to the 3′-proximal part of PVX RNA were efficiently translated into the PVX coat protein and 2 as yet unidentified small hydrophobic proteins. © 1990.