The role of IRES trans-acting factors in regulating translation initiation.

@article{King2010TheRO,
  title={The role of IRES trans-acting factors in regulating translation initiation.},
  author={Helen A King and Laura C. Cobbold and Anne E. Willis},
  journal={Biochemical Society transactions},
  year={2010},
  volume={38 6},
  pages={
          1581-6
        }
}
The majority of mRNAs in eukaryotic cells are translated via a method that is dependent upon the recognition of, and binding to, the methylguanosine cap at the 5' end of the mRNA, by a set of protein factors termed eIFs (eukaryotic initiation factors). However, many of the eIFs involved in this process are modified and become less active under a number of pathophysiological stress conditions, including amino acid starvation, heat shock, hypoxia and apoptosis. During these conditions, the… 

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This review will clearly explain the required experiments, and the pros and cons of various assays, used to determine whether (or not) an RNA element functions as an IRES to promote initiation of translation and hopes that demystifying the accepted methods for assaying IRES activity will open the study of this important mechanism to the broader community.
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The protein domains that are responsible for RNA binding as well as the RNA motifs to which they bind, and the role of trans‐acting ribosomal proteins in directing the translation of specific mRNAs are discussed.
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A novel bicistronic reporter that exploits the 2A “stop-go” peptide was developed to allow the detection of IRES-mediated translation in vivo and ensures that both 0 frame viral structural proteins and +1 frame ORFx protein are optimally expressed during virus infection.
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