Evidence for in vitro and in vivo autocatalytic processing of the primary translation product of beet necrotic yellow vein virus RNA 1 by a papain-like proteinase.
Beet necrotic yellow vein virus RNA 1 contains a single long ORF corresponding to the theoretical translation product of 237 kDa which contains the information necessary for replication of the viral genome. This ORF contains a putative papain-like proteinase domain which has been localized, on the basis of sequence alignments, between the helicase and polymerase domains. Here we show that the RNA 1 primary translation product can be cleaved autocatalytically in vitro into two species of 150 kDa and 66 kDa, the latter of which probably contains the entire polymerase domain. A 66 kDa protein was detected immunologically in infected C. quinoa protoplasts using an antiserum specific for the C-terminal region of the RNA 1 primary translation product, confirming that processing also occurs in vivo.
Hehn
A
A
Institut de Biologie Moléculaire des Plantes, Strasbourg, France.
Fritsch
C
C
Richards
K E
KE
Guilley
H
H
Jonard
G
G
D000595:Amino Acid Sequence; D008969:Molecular Sequence Data; D010206:Papain / Q000494:pharmacology; D010942:Plant Viruses / Q000235:genetics*; D014176:Protein Biosynthesis; D012328:RNA Viruses / Q000235:genetics*; D012367:RNA, Viral / Q000235:genetics*
D012367:RNA, Viral; D010206:Papain