Viral initiation of translation
Many viruses have evolved altrnative ways to initiate viral mRNA translation.The reason is either that the virus shuts off classic host translation, or because the viral RNAs are non-classical, missing a cap or polyadenylation.
Internal Ribosome Entry Site (IRES) are RNA structures that allow cap independent initiation of translation, and are able to initiate translation in the middle of a messenger RNA. Cripavirus IRES also allow the translation initiation on a Alanine or Glutamine tRNA.
Downstream Hairpin Loop (DLP) are RNA structures that allow initiation of cap dependent translation in the absence of eIF2 initiation factor, where the initiating methionine tRNA is placed by the DLP structure on the ribosome.
CUG initiation involves initiation with a leucine, and is more likely to occur upon stress with eIF2 inhibition .
Inhibition of host translation by virus infection in vivo
Ren? Toribio, Iv?n Ventoso
Proc. Natl. Acad. Sci. U.S.A. May 25, 2010; 107: 9837?9842
CUG initiation codon used for the synthesis of a cell surface antigen coded by the murine leukemia virus
A. C. Prats, G. De Billy, P. Wang, J. L. Darlix
J. Mol. Biol. January 20, 1989; 205: 363?372
The DNA virus white spot syndrome virus uses an internal ribosome entry site for translation of the highly expressed nonstructural protein ICP35
Shih-Ting Kang, Han-Ching Wang, Yi-Ting Yang, Guang-Hsiung Kou, Chu-Fang Lo
J. Virol. December 2013; 87: 13263-13278
Polycistronic mRNAs and internal ribosome entry site elements (IRES) are widely used by white spot syndrome virus (WSSV) structural protein genes
Shih-Ting Kang, Jiann-Horng Leu, Han-Ching Wang, Li-Li Chen, Guang-Hsiung Kou, Chu-Fang Lo
Virology May 10, 2009; 387: 353-363
Specific interaction of eukaryotic translation initiation factor 3 with the 5? nontranslated regions of hepatitis C virus and classical swine fever virus RNAs
D. V. Sizova, V. G. Kolupaeva, T. V. Pestova, I. N. Shatsky, C. U. Hellen
J. Virol. June 1998; 72: 4775-782
Unanticipated antigens: translation initiation at CUG with leucine
Susan R. Schwab, Jessica A. Shugart, Tiffany Horng, Subramaniam Malarkannan, Nilabh Shastri
PLoS Biol. November 2004; 2: e366