Cap-poly(A) synergy in mammalian cell-free extracts. Investigation of the requirements for poly(A)-mediated stimulation of translation initiation
| Autor: | Michel, Yanne M., Poncet, Didier, Piron, Maria, Kean, Katherine M., Borman, Andrew M. |
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| Přispěvatelé: | Génétique Moléculaire des Virus Respiratoires, Institut Pasteur [Paris] (IP)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche Virologie et Immunologie Moléculaires (VIM (UR 0892)), Institut National de la Recherche Agronomique (INRA), Work in the laboratory of K. M. K. was supported by the Program de Recherche Clinique de l'Institut Pasteur and by Grant 6495 from the Association Française Contre les Myopathies., Régulation de la traduction eucaryote et virale, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Institut Pasteur [Paris], Vall d'Hebron University Hospital [Barcelona] |
| Jazyk: | angličtina |
| Rok vydání: | 2000 |
| Předmět: |
Cell Extracts
Rotavirus Reticulocytes STRUCTURE MESH: Rabbits Viral Nonstructural Proteins stimulation MESH: Poly(A)-Binding Proteins MESH: RNA Caps infection virale Peptide Initiation Factors adénine MESH: Cell Extracts MESH: Cell-Free System MESH: Animals Encephalomyocarditis virus polyadenylation Peptide Chain Initiation Translational MESH: Peptide Initiation Factors MESH: Encephalomyocarditis virus immunologie moléculaire RNA-Binding Proteins mammifère MESH: Rotavirus MESH: Eukaryotic Initiation Factor-4G VIROLOGIE MESH: Nucleic Acid Conformation protéine Rabbits MESH: Poly A arn messager transcription Plasmids Protein Binding RNA Caps MESH: Peptide Chain Initiation Translational génétique moléculaire Poly(A)-Binding Proteins MESH: Plasmids Animals Humans MESH: Protein Binding [SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry Molecular Biology/Biochemistry [q-bio.BM] Binding Sites MESH: Humans Cell-Free System MESH: Ultracentrifugation MESH: Reticulocytes initiation MESH: RNA-Binding Proteins arn t MESH: Binding Sites MESH: HeLa Cells Nucleic Acid Conformation MESH: Viral Nonstructural Proteins Eukaryotic Initiation Factor-4G Poly A Ribosomes Ultracentrifugation MESH: Ribosomes HeLa Cells |
| Zdroj: | Journal of Biological Chemistry 41 (275), 32268-32276. (2000) Journal of Biological Chemistry Journal of Biological Chemistry, 2000, 275 (41), pp.32268-32276. ⟨10.1074/jbc.M004304200⟩ Journal of Biological Chemistry, American Society for Biochemistry and Molecular Biology, 2000, 275 (41), pp.32268-32276. ⟨10.1074/jbc.M004304200⟩ |
| ISSN: | 0021-9258 1083-351X |
| DOI: | 10.1074/jbc.M004304200⟩ |
| Popis: | 35 ref.; International audience; The 5' cap and 3' poly(A) tail of eukaryotic mRNAs cooperate to stimulate synergistically translation initiation in vivo, a phenomenon observed to date in vitro only in translation systems containing endogenous competitor mRNAs. Here we describe nuclease-treated rabbit reticulocyte lysates and HeLa cell cytoplasmic extracts that reproduce cap-poly(A) synergy in the absence of such competitor RNAs. Extracts were rendered poly(A)-dependent by ultracentrifugation to partially deplete them of ribosomes and associated initiation factors. Under optimal conditions, values for synergy in reticulocyte lysates approached 10-fold. By using this system, we investigated the molecular mechanism of poly(A) stimulation of translation. Maximal cap-poly(A) cooperativity required the integrity of the eukaryotic initiation factor 4G-poly(A)-binding protein (eIF4G-PABP) interaction, suggesting that synergy results from mRNA circularization. In addition, polyadenylation stimulated uncapped cellular mRNA translation and that driven by the encephalomyocarditis virus internal ribosome entry segment (IRES). These effects of poly(A) were also sensitive to disruption of the eIF4G-PABP interaction, suggesting that 5'-3' end cross-talk is functionally conserved between classical mRNAs and an IRES-containing mRNA. Finally, we demonstrate that a rotaviral non-structural protein that evicts PABP from eIF4G is capable of provoking the shut-off of host cell translation seen during rotavirus infection. |
| Databáze: | OpenAIRE |
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