Host-dependent roles of the viral 5' untranslated region (UTR) in RNA stabilization and cap-independent translational enhancement mediated by the 3' UTR of Red clover necrotic mosaic virus RNA1.
The genome of Red clover necrotic mosaic virus (RCNMV) consists of RNA1 and RNA2, both lacking a cap structure and a poly(A)tail. RNA1 has a translational enhancer element (3'TE-DR1) in the 3' untranslated region (UTR). In this study, we analyzed the roles of 5' and 3' UTRs of RNA1 in 3'TE-DR1-mediated cap-independent translation in cowpea and tobacco BY-2 protoplasts using a dual-luciferase (Luc) reporter assay system. Most mutations introduced into RNA1 5' UTR in reporter Luc mRNA abolished or greatly reduced cap-independent translation in BY-2 protoplasts, whereas those mutations had no or much milder effects if any on translational activity in cowpea protoplasts. Our results suggest that a stem-loop structure predicted in the 5' proximal region of RNA1 plays important roles in both translation and RNA stability. We also show that 3'TE-DR1-mediated cap-independent translation relies on a ribosome-scanning mechanism in both protoplasts.
Sarawaneeyaruk
Siriruk
S
Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kitashirakawa, Kyoto, 606-8502, Japan.
Iwakawa
Hiro-Oki
HO
Mizumoto
Hiroyuki
H
Murakami
Hiromi
H
Kaido
Masanori
M
Mise
Kazuyuki
K
Okuno
Tetsuro
T
D020413:3' Untranslated Regions; D020121:5' Untranslated Regions; D001483:Base Sequence; D002478:Cells, Cultured; D007887:Fabaceae / Q000821:virology; D016679:Genome, Viral; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D014176:Protein Biosynthesis; D012315:RNA Caps; D020871:RNA Stability; D012367:RNA, Viral / Q000235:genetics*; D014026:Nicotiana / Q000821:virology; D019183:Tombusviridae / Q000235:genetics*; D014764:Viral Proteins
D020413:3' Untranslated Regions; D020121:5' Untranslated Regions; D012315:RNA Caps; D012367:RNA, Viral; D014764:Viral Proteins