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Structural basis for ribosome recruitment and manipulation by a viral IRES RNA.

ABSTRACT: Canonical cap-dependent translation initiation requires a large number of protein factors that act in a stepwise assembly process. In contrast, internal ribosomal entry sites (IRESs) are cis-acting RNAs that in some cases completely supplant these factors by recruiting and activating the ribosome using a single structured RNA. Here we present the crystal structures of the ribosome-binding domain from a Dicistroviridae intergenic region IRES at 3.1 angstrom resolution, providing a view of the prefolded architecture of an all-RNA translation initiation apparatus. Docking of the structure into cryo-electron microscopy reconstructions of an IRES-ribosome complex suggests a model for ribosome manipulation by a dynamic IRES RNA.

SUBMITTER: Pfingsten JS

PROVIDER: S-EPMC2669756 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature

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Structural basis for ribosome recruitment and manipulation by a viral IRES RNA.

Pfingsten Jennifer S JS Costantino David A DA Kieft Jeffrey S JS

Science (New York, N.Y.) 20061123 5804

Canonical cap-dependent translation initiation requires a large number of protein factors that act in a stepwise assembly process. In contrast, internal ribosomal entry sites (IRESs) are cis-acting RNAs that in some cases completely supplant these factors by recruiting and activating the ribosome using a single structured RNA. Here we present the crystal structures of the ribosome-binding domain from a Dicistroviridae intergenic region IRES at 3.1 angstrom resolution, providing a view of the pre ...[more]

PMID: 17124290

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