Conservation of RNA structures enables TNV and BYDV 5' and 3' elements to cooperate synergistically in cap-independent translation.
The subgenomic RNA 2 of tobacco necrosis virus A (TNV sgRNA2) encodes the viral coat protein, is unpolyadenylated and presumably uncapped. Here, we show that TNV sgRNA2 is translated cap independently. This cap-independent translation requires the leader and a 140 nt element of the trailer both in wheat germ extract and in tobacco protoplasts. Similar to barley yellow dwarf virus (BYDV), the TNV 5' and 3' elements stimulate translation synergistically. Computer-aided phylogenetic analysis of the secondary structure of the TNV trailer revealed that the 3' translation element is part of a major conserved stem-loop that contains similarities to structures in the BYDV 3' translation element. These data suggest that the translation mechanisms of TNV sgRNA2 and BYDV RNA are related. To further characterize this relationship, we tested whether cooperativity exists between TNV sgRNA2 and BYDV 5' and 3' elements. We found that the TNV sgRNA2 5' element stimulates translation synergistically with the BYDV 3' element in vitro. This finding is the first evidence for conservation of structures that enable a 5'-3' interaction stimulating cap-independent translation.
Meulewaeter
Frank
F
Bayer BioScience N.V., J. Plateaustraat 22, B-9000, Gent, Belgium. frank.meulewaeter@bayercropscience.com
van Lipzig
Rosalinde
R
Gultyaev
Alexander P
AP
Pleij
Cornelis W A
CW
Van Damme
Daniel
D
Cornelissen
Marc
M
van Eldik
Gerben
G
D020413:3' Untranslated Regions; D020121:5' Untranslated Regions; D001483:Base Sequence; D036022:Capsid Proteins / Q000235:genetics; D017793:Luteovirus / Q000235:genetics*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010802:Phylogeny; D014176:Protein Biosynthesis; D012315:RNA Caps; D012367:RNA, Viral / Q000737:chemistry*; D025641:Tobacco necrosis satellite virus / Q000235:genetics*
D020413:3' Untranslated Regions; D020121:5' Untranslated Regions; D036022:Capsid Proteins; D012315:RNA Caps; D012367:RNA, Viral