Ribosome Footprinting of WT and mutant yeast cells at different temperatures
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ABSTRACT:
ORGANISM(S): Saccharomyces cerevisiae
PROVIDER: GSE131176 | GEO | 2020/04/30
REPOSITORIES: GEO
Similar Datasets
Project description:DEAD-box RNA helicases eIF4A and Ded1 are believed to promote translation initiation by resolving mRNA secondary structures that impede ribosome attachment at the mRNA 5’ end or subsequent scanning of the 5’UTR, but whether they perform distinct functions or act redundantly in vivo is poorly understood. We compared the effects of mutations in Ded1 or eIF4A on global translational efficiencies (TEs) in yeast by ribosome footprint profiling. Despite similar reductions in bulk translation, inactivation of a cold-sensitive Ded1 mutant substantially reduced the TEs of >600 mRNAs, whereas inactivation of a temperature-sensitive eIF4A mutant yielded <40 similarly impaired mRNAs. The broader requirement for Ded1 did not reflect more pervasive secondary structures at low temperature, as inactivation of temperature-sensitive and cold-sensitive ded1 mutants gave highly correlated results. Interestingly, Ded1-dependent mRNAs exhibit greater than average 5’UTR length and propensity for secondary structure, implicating Ded1 in scanning though structured 5' UTRs. Reporter assays confirmed that cap- distal stem-loop insertions increase dependence on Ded1 but not eIF4A for efficient translation. While only a small fraction of mRNAs is strongly dependent on eIF4A, this dependence is significantly correlated with requirements for Ded1 and 5’UTR features characteristic of Ded1- dependent mRNAs. Our findings suggest that Ded1 is critically required to promote scanning through secondary structures within 5’UTRs; and while eIF4A cooperates with Ded1 in this function, it also promotes a step of initiation common to virtually all yeast mRNAs. We compared the effects of mutations in Ded1 or eIF4A on global translational efficiencies (TEs) in yeast by ribosome footprint profiling.The study includes 32 samples, comprised of 16 mRNA-Seq samples and 16 ribosome footprint profiling samples, derived from biological replicates of 3 mutant strains, ded1-cs, ded1-ts and tif1-ts, and the corresponding wild-type strains. The tif1-ts mutant and its wild-type counterpart were analyzed at 30°C and 37°C.
2015-03-02 | E-GEOD-66411 | biostudies-arrayexpress
Project description:DEAD-box RNA helicases eIF4A and Ded1 are believed to promote translation initiation by resolving mRNA secondary structures that impede ribosome attachment at the mRNA 5’ end or subsequent scanning of the 5’UTR, but whether they perform distinct functions or act redundantly in vivo is poorly understood. We compared the effects of mutations in Ded1 or eIF4A on global translational efficiencies (TEs) in yeast by ribosome footprint profiling. Despite similar reductions in bulk translation, inactivation of a cold-sensitive Ded1 mutant substantially reduced the TEs of >600 mRNAs, whereas inactivation of a temperature-sensitive eIF4A mutant yielded <40 similarly impaired mRNAs. The broader requirement for Ded1 did not reflect more pervasive secondary structures at low temperature, as inactivation of temperature-sensitive and cold-sensitive ded1 mutants gave highly correlated results. Interestingly, Ded1-dependent mRNAs exhibit greater than average 5’UTR length and propensity for secondary structure, implicating Ded1 in scanning though structured 5' UTRs. Reporter assays confirmed that cap- distal stem-loop insertions increase dependence on Ded1 but not eIF4A for efficient translation. While only a small fraction of mRNAs is strongly dependent on eIF4A, this dependence is significantly correlated with requirements for Ded1 and 5’UTR features characteristic of Ded1- dependent mRNAs. Our findings suggest that Ded1 is critically required to promote scanning through secondary structures within 5’UTRs; and while eIF4A cooperates with Ded1 in this function, it also promotes a step of initiation common to virtually all yeast mRNAs.
2015-03-02 | GSE66411 | GEO
Project description:We use RNAseq to assess the gene expression as well as solubility of transcripts after 10 minutes of heat stress at either 40°C or 42°C compared to non-stressed yeast cells (30°C) for wildtype and Ded1-IDRm mutant cells.
2019-11-26 | GSE141029 | GEO
Project description:We have developed a deep sequencing-based approach, Rec-Seq, that allows simultaneous monitoring of ribosomal 48S pre-initiation complex (PIC) formation on every mRNA in the translatome in an in vitro reconstituted system. Rec-Seq isolates key early steps in translation initiation in the absence of all other cellular components and processes. Using this approach we show that the DEAD-box ATPase Ded1 promotes 48S PIC formation on the start codons of >1000 native mRNAs, most of which have long, structured 5’-untranslated regions (5’UTRs). Remarkably, initiation measured in Rec-Seq was enhanced by Ded1 for most mRNAs previously shown to be highly Ded1-dependent by ribosome profiling of ded1 mutants in vivo, demonstrating that the core translation functions of the factor are recapitulated in the purified system. Our data do not support a model in which Ded1acts by reducing initiation at start codons in 5’UTRs and instead indicate it functions by directly promoting mRNA recruitment to the 43S PIC and scanning to locate the start codon. We also provide evidence that eIF4A, another essential DEAD-box initiation factor, is required for efficient PIC assembly on almost all mRNAs, regardless of their structural complexity, in contrast to the preferential stimulation by Ded1 of initiation on mRNAs with long, structured 5’UTRs.
2023-10-03 | GSE244093 | GEO
Project description:DEAD-box RNA helicases eIF4A and Ded1 promote translation by resolving mRNA secondary structures that impede preinitiation complex (PIC) attachment to mRNA or scanning. eIF4B is a cofactor for eIF4A but might also function independently of eIF4A. Ribosome profiling of mutants lacking eIF4B or with impaired eIF4A or Ded1 activity revealed that eliminating eIF4B reduces the relative translational efficiencies of many more genes than does inactivation of eIF4A, despite comparable reductions in bulk translation, and few genes display unusually strong requirements for both factors. However, either eliminating eIF4B or inactivating eIF4A preferentially impacts mRNAs with longer, more structured 5’UTRs. These findings reveal an eIF4A-independent role for eIF4B in addition to its function as eIF4A cofactor in promoting PIC attachment or scanning on structured mRNAs. eIF4B, eIF4A, and Ded1 mutations also preferentially impair translation of longer mRNAs in a fashion mitigated by the ability to form closed-loop mRNPs via eIF4F-Pab1 association, suggesting cooperation between closed-loop assembly and eIF4B/helicase functions. Remarkably, depleting eIF4G, the scaffold subunit of eIF4F, preferentially impacts short mRNAs with strong closed-loop potential and unstructured 5’UTRs, exactly the opposite features associated with hyperdependence on the eIF4B/helicases. We propose that short, highly efficient mRNAs preferentially depend on the stimulatory effects of eIF4G-dependent closed-loop assembly.
2016-05-27 | GSE81966 | GEO
Project description:We analyzed the effect of deleting the gene encoding putative RNA helicase DBP1 in budding yeast on translational efficiencies (TEs) genome wide in wild-type or ded1-ts (temperature-sensitive allele of DED1) strains by combining ribosome footprint profiling with RNA-seq analysis of mRNA abundance. This study includes a total of 32 samples comprised of 16 RNA-Seq samples (mRNA) and 16 ribosome footprint profiling samples (ribo). Experiment 1 includes 8 samples, comprised of 4 RNA-Seq samples and 4 ribosome footprint profiling samples, derived from 2 biological replicates each of the dbp1Δ and ded1-ts dbp1Δ mutant strains, cultured in synthetic complete (SC) medium, following shifts in growth temperature from 30°C to 37°C for 2h. Experiment 2 examines the effect of overexpression of DBP1 in rescuing genome-wide translational defects of a ded1-cs mutant (cold-sensitive allele of DED1) and includes 12 samples, 6 RNA-Seq samples and 6 ribosome footprint profiling samples, derived from 2 biological replicates each of WT DED1 (dubbed DED1-CS), ded1-cs and ded1-cs overexpressing DBP1 (ded1-cs_hcDBP1) strains, cultured in SC-Leu-His medium, following shifts in growth temperature from 30°C to 15°C for 10 min. Experiment 3 examines rescue of translational defects of ded1-ts by DBP1 overexpression and includes 12 samples, 6 RNA-Seq samples and 6 ribosome footprint profiling samples, derived from 2 biological replicates each of WT DED1(DED1-TS), ded1-ts and ded1-ts overexpressing DBP1 (ded1-ts_hcDBP1) strains, cultured in SC-Leu-His medium, following shifts in growth temperature from 30°C to 37°C for 2h.
2018-03-01 | GSE111255 | GEO
Project description:BACKGROUND: We previously demonstrated that temperature-related microwave ablation (MWA) can safely regulate vertebral growth plates of piglets. Therefore, the present study was designed to investigate the effects of different temperatures on chondrocyte proliferation and the molecular mechanisms involved in vitro. METHODS: After treatment for 10 min using different temperatures (37°C, 40°C, 42°C, 44°C, 46°C, 48°C, or 50°C), CCK-8 assay examined the activity of ATDC5 cells at 12 hr. RNA-seq identified differentially expressed genes (DEGs) and the hub genes in ATDC5 cells treated at 37°C, 40°C and 44°C. RT-qPCR verified the differential expression of hub genes in ATDC5 cells. RESULTS: Compared with 37°C, stimulation at 40°C significantly enhanced the activity of ATDC5 cells, and 40°C had no significant effect. In addition, stimulation at 44°C, 46°C, 48°C, or 50°C exhibited the opposite pattern, and ATDC5 cells were particularly less than 50% active after treatment at 46°C, 48°C, or 50°C. Differential expression analysis revealed the presence of 179, 374 and 221 DEGs in 40°C vs. 37°C, 44°C vs. 37°C, and 44°C vs. 40°C, respectively. Enrichment analysis indicated that these DEGs predominantly regulate proliferation, differentiation, necrosis, inflammatory and immune responses, and ECM synthesis/degradation, and that they are associated with the Ras, PI3K/AKT, mTOR, cAMP, and MAPK pathways. Furthermore, Agt, Hspa1a, Hspb1, and Nlrc4 were hub genes in DEGs, and RT-qPCR confirmed that the mRNA expression patterns of these hub genes in ATDC5 cells were essentially consistent with the RNA-seq results. CONCLUSION: Temperature-mediated chondrocyte proliferation was associated with Ras, PI3K/AKT, mTOR, cAMP, and MAPK pathways, and Agt, Hspa1a, Hspb1, and Nlrc4 may be the key regulatory genes.
2024-12-10 | GSE269585 | GEO
Project description:DEAD-box RNA helicases are ATP-dependent RNA binding proteins and RNA-dependent ATPases that possess weak, nonprocessive unwinding activity in vitro, but they can form long-lived complexes on RNAs when the ATPase activity is inhibited. Ded1 is a yeast DEAD-box protein, the functional ortholog of mammalian DDX3, that is considered important for the scanning efficiency of the 48S pre-initiation complex ribosomes to the AUG start codon. We used a modified PAR-CLIP technique, which we call quicktime PAR-CLIP (qtPAR-CLIP) to crosslink Ded1 to 4-thiouridine-incorported RNAs in vivo using UV light centered at 365 nm. The irradiation conditions are largely benign to the yeast cells and to Ded1, and we are able to obtain a high efficiency of crosslinking under physiological conditions. We find that Ded1 forms crosslinks on the open reading frames of many different mRNAs, but it forms the most extensive interactions on a relatively few mRNAs, and particularly on mRNAs encoding certain ribosomal proteins and translation factors. Under glucose-depletion conditions the crosslinking pattern shifts to mRNAs encoding metabolic and stress-related proteins, which reflects the altered translation. These data are consistent with Ded1 functioning in the regulation of translation elongation, perhaps by pausing or stabilizing the ribosomes through its ATP-dependent binding.
2023-08-01 | GSE228828 | GEO
Project description:Ribosome Footprinting of WT and mutant yeast cells at different temperatures
| PRJNA542817 | ENA