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Three distinct ribosome assemblies modulated by translation are the building blocks of polysomes.

ABSTRACT: Translation is increasingly recognized as a central control layer of gene expression in eukaryotic cells. The overall organization of mRNA and ribosomes within polysomes, as well as the possible role of this organization in translation are poorly understood. Here we show that polysomes are primarily formed by three distinct classes of ribosome assemblies. We observe that these assemblies can be connected by naked RNA regions of the transcript. We show that the relative proportions of the three classes of ribosome assemblies reflect, and probably dictate, the level of translational activity. These results reveal the existence of recurrent supra-ribosomal building blocks forming polysomes and suggest the presence of unexplored translational controls embedded in the polysome structure.

SUBMITTER: Viero G

PROVIDER: S-EPMC4347638 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Three distinct ribosome assemblies modulated by translation are the building blocks of polysomes.

Viero Gabriella G Lunelli Lorenzo L Passerini Andrea A Bianchini Paolo P Gilbert Robert J RJ Bernabò Paola P Tebaldi Toma T Diaspro Alberto A Pederzolli Cecilia C Quattrone Alessandro A

The Journal of cell biology 20150223 5

Translation is increasingly recognized as a central control layer of gene expression in eukaryotic cells. The overall organization of mRNA and ribosomes within polysomes, as well as the possible role of this organization in translation are poorly understood. Here we show that polysomes are primarily formed by three distinct classes of ribosome assemblies. We observe that these assemblies can be connected by naked RNA regions of the transcript. We show that the relative proportions of the three c ...[more]

PMID: 25713412

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