Translational control in positive strand RNA plant viruses.
The great variety of genome organizations means that most plant positive strand viral RNAs differ from the standard 5'-cap/3'-poly(A) structure of eukaryotic mRNAs. The cap and poly(A) tail recruit initiation factors that support the formation of a closed loop mRNA conformation, the state in which translation initiation is most efficient. We review the diverse array of cis-acting sequences present in viral mRNAs that compensate for the absence of a cap, poly(A) tail, or both. We also discuss the cis-acting sequences that control translation strategies that both amplify the coding potential of a genome and regulate the accumulations of viral gene products. Such strategies include leaky scanning initiation of translation of overlapping open reading frames, stop codon readthrough, and ribosomal frameshifting. Finally, future directions for research on the translation of plant positive strand viruses are discussed.
Dreher
Theo W
TW
Department of Microbiology and Center for Gene Research and Biotechnology, 220 Nash Hall, Oregon State University, Corvallis, OR 97331, USA. theo.dreher@oregonstate.edu
Miller
W Allen
WA
D020413:3' Untranslated Regions; D018388:Codon, Terminator; D018965:Frameshifting, Ribosomal; D016679:Genome, Viral; D010942:Plant Viruses / Q000235:genetics* / Q000378:metabolism; D014176:Protein Biosynthesis; D012315:RNA Caps; D012328:RNA Viruses / Q000235:genetics* / Q000378:metabolism; D014764:Viral Proteins / Q000378:metabolism
D020413:3' Untranslated Regions; D018388:Codon, Terminator; D012315:RNA Caps; D014764:Viral Proteins