Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA371822 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Here we show eIF4A2 is a major effector of the represive miRNA pathway functioning via the Ccr4_Not complex; through its interaction with the Ccr4-Not complex eIF4A2 represses mRNAs at translation initiation. We show evidence that native eIF4A2 has similar properties to chemically inhibited eIF4A1. eIF4A2 exerts its repressive effect by binding purine-rich motifs which are enriched in the 5'UTR directly upstream of the AUG codon.
2019-10-10 | PXD015772 | Pride
Project description:Background: Regulation of the mRNA life cycle is central to gene expression control and determination of cell fate. miRNAs represent a critical mRNA regulatory mechanism, but despite decades of research, their mode of action is still not fully understood. Results: Here, we show that eIF4A2 is a major effector of the repressive miRNA pathway functioning via the Ccr4-Not complex. We demonstrate that while DDX6 interacts with Ccr4-Not, its effects in the mechanism are not as pronounced. Through its interaction with the Ccr4- Not complex, eIF4A2 represses mRNAs at translation initiation. We show evidence that native eIF4A2 has similar RNA-selectivity to chemically inhibited eIF4A1. eIF4A2 exerts its repressive effect by binding purine-rich motifs which are enriched in the 5’UTR of target mRNAs directly upstream of the AUG start codon. Conclusions: Our data support a model whereby purine motifs towards the 3’ end of the 5’UTR are associated with increased ribosome occupancy and possible uORF activation upon eIF4A2 binding.
2019-10-09 | GSE94690 | GEO
Project description:Regulation of the mRNA life-cycle is central to gene expression control and determination of cell fate. miRNAs represent a critical mRNA regulatory mechanism, but despite decades of research, their mode of action is still not fully understood. Here we show eIF4A2 is a major effector of the repressive miRNA pathway functioning via the Ccr4-Not complex. We demonstrate that while DDX6 interacts with Ccr4-Not, its effects in the mechanism are not as pronounced. Through its interaction with the Ccr4-Not complex eIF4A2 represses mRNAs at translation initiation. We show evidence that native eIF4A2 has similar properties to chemically inhibited eIF4A1. We demonstrate that eIF4A2 exerts it repressive effect by binding purine-rich motifs which are enriched in the 5’UTR directly upstream of the AUG start codon. The data supports a model whereby purine motifs towards the 3’ end of the 5’UTR are associated with increased ribosome occupancy and possible uORF activation similar to that observed for mRNAs affected by inhibited eIF4A1.
2019-10-08 | PXD014764 | Pride
Project description:Stemness is a defining feature in embryonic and cancer stem cells. How stemness is regulated at the mRNA translational initiation remains undefined. We carried out an RNAi screen for key translation initiation factors that maintain the stemness in mouse embryonic stem cells (ESCs). We identified eIF4A2 and defined its mechanistic action through Rps26-depleted and -containing ribosomes in translational initiation activation of mRNAs encoding pluripotency factors and H3.3 for embryonic and extraembryonic lineage repression, respectively. eIF4A2 also mediates translation initiation activation of Ddx6, which acts together with eIF4A2 to restrict the totipotent 2-cell (2C) transcription program in ESCs through Zscan4 mRNA degradation and translation repression. Knockdown of eIF4A2 disrupts ESC proteome causing the loss of stemness in ESCs as well as in human glioblastomas where eIF4A2 is highly enriched. Collectively, our study establishes an eIF4A2-mediated translation initiation control of stemness and provides insight into cancer therapeutics targeting the translation initiation machinery.
2022-04-20 | GSE150680 | GEO
Project description:Stemness is a defining feature in embryonic and cancer stem cells. How stemness is regulated at the mRNA translational initiation remains undefined. We carried out an RNAi screen for key translation initiation factors that maintain the stemness in mouse embryonic stem cells (ESCs). We identified eIF4A2 and defined its mechanistic action through Rps26-depleted and -containing ribosomes in translational initiation activation of mRNAs encoding pluripotency factors and H3.3 for embryonic and extraembryonic lineage repression, respectively. eIF4A2 also mediates translation initiation activation of Ddx6, which acts together with eIF4A2 to restrict the totipotent 2-cell (2C) transcription program in ESCs through Zscan4 mRNA degradation and translation repression. Knockdown of eIF4A2 disrupts ESC proteome causing the loss of stemness in ESCs as well as in human glioblastomas where eIF4A2 is highly enriched. Collectively, our study establishes an eIF4A2-mediated translation initiation control of stemness and provides insight into cancer therapeutics targeting the translation initiation machinery.
2022-04-20 | GSE150676 | GEO
Project description:Stemness is a defining feature in embryonic and cancer stem cells. How stemness is regulated at the mRNA translational initiation remains undefined. We carried out an RNAi screen for key translation initiation factors that maintain the stemness in mouse embryonic stem cells (ESCs). We identified eIF4A2 and defined its mechanistic action through Rps26-depleted and -containing ribosomes in translational initiation activation of mRNAs encoding pluripotency factors and H3.3 for embryonic and extraembryonic lineage repression, respectively. eIF4A2 also mediates translation initiation activation of Ddx6, which acts together with eIF4A2 to restrict the totipotent 2-cell (2C) transcription program in ESCs through Zscan4 mRNA degradation and translation repression. Knockdown of eIF4A2 disrupts ESC proteome causing the loss of stemness in ESCs as well as in human glioblastomas where eIF4A2 is highly enriched. Collectively, our study establishes an eIF4A2-mediated translation initiation control of stemness and provides insight into cancer therapeutics targeting the translation initiation machinery.
2022-04-20 | GSE150673 | GEO
Project description:Eukaryotic initiation factor (eIF) 4A is a DEAD-box RNA-binding protein that plays a pivotal role in translation initiation. Although mammals have two eIF4A paralogs, eIF4A1 and eIF4A2, their redundancy has been long assumed because of high homology and their functional difference has been poorly understood. Here we show that eIF4A paralogs employ differential translation programs. Ribosome profiling of eIF4A1- and eIF4A2-knockout HEK293T cell lines revealed that translation efficiency changes were divergent across transcriptome and distinct group of mRNAs were regulated by each paralog. Our analysis indicates that eIF4A1 and eIF4A2 facilitate translation of specific mRNAs.
2019-10-26 | GSE126298 | GEO
Project description:Cell fate transitions depend on balanced rewiring of transcription and translation programmes to enable ordered developmental progression. We identified a feedback loop between nonsense-mediated mRNA decay (NMD) and translation initiation, in which NMD controls the translation initiation factor Eif4a2 and its premature termination codon encoding isoform (Eif4a2-PTC). This leads to translation of a specific truncated protein, which elicits increased translation rates and is causative for significant delays in mouse embryonic stem cell differentiation. Using immunoprecipitation coupled with mass spectrometry, we identified the interactome of full length Eif4a2 (Eif4a2-iso1) and Eif4a2-PTC. We find that Eif4a2-iso1 is mainly involved in translation initiation, while unstable Eif4a2-PTC shows little interaction with translation initiation factors. Both isoforms can bind to mRNA, as indicated by the interaction with mRNA binding protein, such as NMD factors and Ago2. Finally, Eif4a2-iso1 and Eif4a2-PTC interact with key pluripotency factors, providing a potential explanation for how Eif4a2 controls ESC differentiation.
2022-03-09 | PXD019588 | Pride
Project description:For the past decade, extensive studies of translation have produced a vast amount of ribosome profiling data, an insightful resource for mining of critical details about the dynamics of translation regulation under various biological contexts. Previously, Rocaglamide A (RocA), an anti-tumor heterotricyclic natural compound, has been shown to selectively inhibit translation initiation of a large group of mRNA species by clamping eukaryotic translation initiation factor 4A (eIF4A) onto poly-purine motifs in the 5’ un-translational regions (5’UTRs). However, re-analysis of the previous ribosome profiling datasets revealed an unexpected shift of the ribosome occupancy pattern during early translation elongation upon RocA treatment in various types of cells, for a specific group of mRNA transcripts without poly-purine motifs over-presented in their 5’UTRs. Such perturbation of the translation elongation dynamics can be attributed to the blockage of translating ribosomes due to the binding of eIF4A to the poly-purine sequence in coding sequences. This new mode of action of RocA, which is complementary to the canonical function inhibiting translation initiation, selectively interfere with the translation of the genes involved in fundamental processes such as ATP synthase, mitochondrial respiratory chain complex, et al. In summary, re-analyses of previous ribosome profiling data has revealed the complete dual modes of RocA in blocking translation and thus underlying the potent anti-tumor effect
2022-12-17 | GSE201364 | GEO
Project description:RNA-immunoprecipitation can be used to identify transcripts bound by RNA binding proteins. Here we identified transcripts bound by the translation initiation factor Eif4a2 in ESCs. We found that several pluripotency transcription factor encoding mRNAs and factors regulating ESC differentiation show binding to Eif4a2 stronger than expected by transcript abundance.
2022-02-02 | GSE153456 | GEO