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Tricks an IRES uses to enslave ribosomes.

ABSTRACT: In eukaryotes, mRNAs are primarily translated through a cap-dependent mechanism whereby initiation factors recruit the 40S ribosomal subunit to a cap structure at the 5' end of the mRNA. However, some viral and cellular messages initiate protein synthesis without a cap. They use a structured RNA element termed an internal ribosome entry site (IRES) to recruit the 40S ribosomal subunit. IRESs were discovered over 20 years ago, but only recently have studies using a model IRES from dicistroviruses expanded our understanding of how a 3D RNA structure can capture and manipulate the ribosome to initiate translation.

SUBMITTER: Thompson SR

PROVIDER: S-EPMC3479354 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Tricks an IRES uses to enslave ribosomes.

Thompson Sunnie R SR

Trends in microbiology 20120831 11

In eukaryotes, mRNAs are primarily translated through a cap-dependent mechanism whereby initiation factors recruit the 40S ribosomal subunit to a cap structure at the 5' end of the mRNA. However, some viral and cellular messages initiate protein synthesis without a cap. They use a structured RNA element termed an internal ribosome entry site (IRES) to recruit the 40S ribosomal subunit. IRESs were discovered over 20 years ago, but only recently have studies using a model IRES from dicistroviruses ...[more]

PMID: 22944245

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