Calicivirus translation initiation requires an interaction between VPg and eIF 4 E.
Unlike other positive-stranded RNA viruses that use either a 5'-cap structure or an internal ribosome entry site to direct translation of their messenger RNA, calicivirus translation is dependent on the presence of a protein covalently linked to the 5' end of the viral genome (VPg). We have shown a direct interaction of the calicivirus VPg with the cap-binding protein eIF 4 E. This interaction is required for calicivirus mRNA translation, as sequestration of eIF 4 E by 4 E-BP 1 inhibits translation. Functional analysis has shown that VPg does not interfere with the interaction between eIF 4 E and the cap structure or 4 E-BP 1, suggesting that VPg binds to eIF 4 E at a different site from both cap and 4 E-BP 1. This work lends support to the idea that calicivirus VPg acts as a novel 'cap substitute' during initiation of translation on virus mRNA.
Goodfellow
Ian
I
School of Animal and Microbial Sciences, University of Reading, Whiteknights, Reading RG6 6AJ, UK. i.g.goodfellow@reading.ac.uk
Chaudhry
Yasmin
Y
Gioldasi
Ioanna
I
Gerondopoulos
Andreas
A
Natoni
Alessandro
A
Labrie
Louisette
L
Laliberté
Jean-François
JF
Roberts
Lisa
L
D002139:Caliciviridae / Q000235:genetics* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D039601:Eukaryotic Initiation Factor-4A; D039561:Eukaryotic Initiation Factor-4E / Q000235:genetics* / Q000378:metabolism; D039562:Eukaryotic Initiation Factor-4F; D039603:Eukaryotic Initiation Factor-4G; D016679:Genome, Viral; D006367:HeLa Cells; D006801:Humans; D039102:Poly(A)-Binding Proteins; D014176:Protein Biosynthesis; D039381:RNA Cap-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism
D039561:Eukaryotic Initiation Factor-4E; D039562:Eukaryotic Initiation Factor-4F; D039603:Eukaryotic Initiation Factor-4G; D039102:Poly(A)-Binding Proteins; D039381:RNA Cap-Binding Proteins; D012367:RNA, Viral; D039601:Eukaryotic Initiation Factor-4A