Identification of novel non-canonical RNA-binding sites in Gemin5 involved in internal initiation of translation
| Autor: | Maria J. Macias, Javier Fernandez-Chamorro, Rosario Francisco-Velilla, Encarnación Martínez-Salas, Jorge Ramajo, David Piñeiro, James M. B. Gordon |
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| Přispěvatelé: | Ministerio de Economía y Competitividad (España), Fundación Ramón Areces |
| Rok vydání: | 2014 |
| Předmět: |
Five prime untranslated region
Amino Acid Motifs Molecular Sequence Data Biology Eukaryotic initiation factor Genetics Initiation factor Humans Amino Acid Sequence Gene Silencing RNA Messenger Peptide Chain Initiation Translational Molecular Biology Binding Sites EIF4E RNA Translation (biology) SMN Complex Proteins Ribonucleoproteins Small Nuclear Eukaryotic translation initiation factor 4 gamma Protein Structure Tertiary Internal ribosome entry site HEK293 Cells Biochemistry Foot-and-Mouth Disease Virus Proteolysis RNA Viral Protein Binding |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname Nucleic Acids Research |
| Popis: | Ribonucleic acid (RNA)-binding proteins are key players of gene expression control. We have shown that Gemin5 interacts with internal ribosome entry site (IRES) elements and modulates initiation of translation. However, little is known about the RNA-binding sites of this protein. Here we show that the C-terminal region of Gemin5 bears two non-canonical bipartite RNA-binding sites, encompassing amino acids 1297-1412 (RBS1) and 1383-1508 (RBS2). While RBS1 exhibits greater affinity for RNA than RBS2, it does not affect IRES-dependent translation in G5-depleted cells. In solution, the RBS1 three-dimensional structure behaves as an ensemble of flexible conformations rather than having a defined tertiary structure. However, expression of the polypeptide G5 1383-1508, bearing the low RNA-binding affinity RBS2, repressed IRES-dependent translation. A comparison of the RNA-binding capacity and translation control properties of constructs expressed in mammalian cells to that of the Gemin5 proteolysis products observed in infected cells reveals that non-repressive products accumulated during infection while the repressor polypeptide is not stable. Taken together, our results define the low affinity RNA-binding site as the minimal element of the protein being able to repress internal initiation of translation. © 2014 The Author(s) 2014. Ministeriode Economia y Competitividad (MINECO) (CSD2009-00080, BFU2011-25437); Fundación Ramón Areces |
| Databáze: | OpenAIRE |
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