4EHP and GIGYF1/2 induce translation-coupled messenger RNA decay
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE144841 | GEO | 2020/10/23
REPOSITORIES: GEO
Similar Datasets
Project description:Although canonical mRNA degradation is generally recognized to be translation dependent, our understanding of the molecular events that coordinate ribosome movement with the decay machinery is still limited. Here, we show that the 4EHP–GIGYF1/2 complex triggers co-translational mRNA decay as a result of altered ribosome activity during elongation. Human cells lacking 4EHP and GIGYF1 and 2 proteins accumulate transcripts known to be degraded in a translation dependent manner or with prominent ribosome pausing. These include mRNAs encoding secretory and membrane-bound proteins or specific tubulin isotypes, among others. 4EHP–GIGYF1/2 fails to reduce target mRNA levels in the absence of ribosome stalling or upon disruption of its interaction with the cap structure, DDX6 and a GYF domain-associated protein. Our studies reveal how a repressor complex linked to neurological disorders minimizes the protein output of a subset of mRNAs.
2020-10-06 | GSE149279 | GEO
Project description:Recent findings indicate that the translation elongation rate influences mRNA stability. One of the factors that has been implicated in this link between mRNA decay and translation speed is the yeast DEAD-box helicase Dhh1p. Here, we demonstrate that the human ortholog of Dhh1p, DDX6, triggers deadenylation-dependent decay of inefficiently translated mRNAs in human cells. DDX6 interacts with the ribosome through the Phe-Asp-Phe (FDF) motif in its RecA2 domain. Furthermore, RecA2-mediated interactions and ATPase activity are both required for DDX6 to destabilize inefficiently translated mRNAs. Using ribosome profiling and RNA sequencing, we identified two classes of endogenous mRNAs that are regulated in a DDX6-dependent manner. The identified targets are either translationally regulated or regulated at the steady-state-level and either exhibit signatures of poor overall translation or of locally reduced ribosome translocation rates. Transferring the identified sequence stretches into a reporter mRNA caused translation- and DDX6-dependent degradation of the reporter mRNA. In summary, these results identify DDX6 as a crucial regulator of mRNA translation and decay triggered by slow ribosome movement and provide insights into the mechanism by which DDX6 destabilizes inefficiently translated mRNAs.
2024-01-23 | GSE231964 | GEO
Project description:MicroRNAs regulate gene expression through deadenylation, repression and mRNA decay. However, the contribution of each mechanism in non-steady-state situations remains unclear. We monitored the impact of miR-430 on ribosome occupancy of endogenous mRNAs in wild type and dicer mutants lacking mature miR-430. Our results indicate that miR-430 reduces the number of ribosomes on target mRNAs before causing mRNA decay. Translational repression occurs before complete deadenylation, and disrupting deadenylation using an internal poly(A) tail did not block target repression. Finally, we observe that ribosome density along the length of the target mRNA remains constant, suggesting that translational repression occurs by reducing the initiation rate rather than reducing elongation or causing ribosomal drop-off. In summary, our results show that miR-430 regulates translation initiation before inducing mRNA decay. Time course parallel ribosome profiling and input mRNA quantification in wildtype and MZdicer mutant embryos
2012-03-15 | E-GEOD-34743 | biostudies-arrayexpress
Project description:Trypanosome RNA polymerase II transcription is polycistronic, individual mRNAs being excised by trans splicing and polyadenylation. In this study, we refined the previously published mathematical model for bloodstream form parasites and extended it to the procyclic form. We used the model, together with known mRNA half-lives, to predict the abundances of individual mRNAs, assuming rapid, unregulated mRNA processing; then we compared the results with measured mRNA abundances. Remarkably, the abundances of most mRNAs in procyclic forms are predicted quite well by the model, being largely explained by variations in mRNA decay rates and length. In bloodstream forms substantially more mRNAs are less abundant than predicted. We list mRNAs that are likely to show particularly slow or inefficient processing, either in both forms or with developmental regulation. We also measured ribosome occupancies of all mRNAs in trypanosomes grown in the same conditions as were used to measure mRNA turnover. In procyclic forms there was a weak positive correlation between ribosome density and mRNA half-life, suggesting cross-talk between translation and mRNA decay; ribosome density was related to the proportion of the mRNA on polysomes, indicating control of translation initiation. Ribosomal protein mRNAs in procyclics appeared to be exceptionally rapidly processed but poorly translated. Through this study, we conclude that lLevels of mRNAs in procyclic form trypanosomes are determined mainly by length and mRNA decay, with some control of precursor processing. In bloodstream forms variations in nuclear events play a larger role in transcriptome regulation, suggesting acquisition of new control mechanisms during adaptation to mammalian parasitism. Ribosome profiling and mRNA libraries were constructed in triplicate from in vitro PCF and in duplicate from in vitro T. brucei Lister427, to understand global differntial gene transcription.
2016-03-16 | E-GEOD-79208 | biostudies-arrayexpress
Project description:Key protein adapters couple translation to mRNA decay on specific classes of problematic mRNAs in eukaryotes. Slow decoding on nonoptimal codons leads to codon-optimality-mediated decay (COMD) and prolonged arrest at stall sites leads to no-go decay (NGD). The identities of the decay factors underlying these processes and the mechanisms by which they respond to translational distress remain open areas of investigation. We use carefully-designed reporter mRNAs to perform genetic screens and functional assays in S. cerevisiae. We characterize the roles of Hel2 and Syh1 in coordinating translational repression and mRNA decay on NGD reporter mRNAs, finding that Syh1 acts as the primary link to mRNA decay in NGD. Importantly we, observe that these NGD factors are not involved in the degradation of mRNAs enriched in nonoptimal codons. Further, we establish that key factors previously implicated in COMD, Not5 and Dhh1 , contribute modestly to the degradation of an NGD-targeted mRNA. Finally, we use ribosome profiling to reveal distinct ribosomal states associated with each reporter mRNA that readily rationalize the contributions of NGD and COMD factors to degradation of these reporters. Taken together, these results provide new mechanistic insight into the role of Syh1 in NGD and define the molecular triggers that determine how distinct pathways target mRNAs for degradation in yeast.
2022-08-08 | PXD030076 | Pride
Project description:A major determinant of mRNA half-life is the codon-dependent rate of translational elongation. How the processes of translational elongation and mRNA decay communicate is unclear. In this study we establish that the DEAD-box helicase Dhh1p is the sensor of codon optimality (i.e. translational elongation rate) that targets an mRNA for decay. First, we find that mRNAs whose translation elongation rate is slowed by inclusion of non-optimal codons are specifically degraded in a DHH1-dependent manner. Biochemical experiments show that Dhh1p is preferentially associated with mRNAs with suboptimal codon choice. We find that these effects on mRNA decay are sensitive to the number of slow moving ribosomes on an mRNA. Using a tethering system, we establish that non-optimal mRNAs become preferentially saturated with ribosomes when Dhh1p is bound. Moreover, over-expression of Dhh1p leads to the accumulation of ribosomes specifically on mRNAs with low codon optimality in ribosome profiling experiments. Lastly, Dhh1p physically interacts with ribosomes in vivo. Together, these data argue that Dhh1p is a sensor for ribosome speed, targeting an mRNA for repression and subsequent decay.
2016-05-11 | GSE81269 | GEO
Project description:Trypanosome RNA polymerase II transcription is polycistronic, individual mRNAs being excised by trans splicing and polyadenylation. In this study, we refined the previously published mathematical model for bloodstream form parasites and extended it to the procyclic form. We used the model, together with known mRNA half-lives, to predict the abundances of individual mRNAs, assuming rapid, unregulated mRNA processing; then we compared the results with measured mRNA abundances. Remarkably, the abundances of most mRNAs in procyclic forms are predicted quite well by the model, being largely explained by variations in mRNA decay rates and length. In bloodstream forms substantially more mRNAs are less abundant than predicted. We list mRNAs that are likely to show particularly slow or inefficient processing, either in both forms or with developmental regulation. We also measured ribosome occupancies of all mRNAs in trypanosomes grown in the same conditions as were used to measure mRNA turnover. In procyclic forms there was a weak positive correlation between ribosome density and mRNA half-life, suggesting cross-talk between translation and mRNA decay; ribosome density was related to the proportion of the mRNA on polysomes, indicating control of translation initiation. Ribosomal protein mRNAs in procyclics appeared to be exceptionally rapidly processed but poorly translated. Through this study, we conclude that lLevels of mRNAs in procyclic form trypanosomes are determined mainly by length and mRNA decay, with some control of precursor processing. In bloodstream forms variations in nuclear events play a larger role in transcriptome regulation, suggesting acquisition of new control mechanisms during adaptation to mammalian parasitism.
2016-03-16 | GSE79208 | GEO
Project description:Cytoplasmic degradation of eukaryotic mRNAs in 3’ to 5’ direction is catalyzed by the exosome complex together with the Ski complex and, in the yeast Saccharomyces cerevisiae, the Ski7 protein. This exosome-Ski-system also degrades ribosome-associated aberrant mRNAs lacking a stop codon, a pathway called non-stop-mRNA decay (NSD). However, the interplay between the Ski components and the ribosome is unknown. Here, we report that the Ski complex can associate with ribosomes in vitro and in vivo independently of Ski7. Ribosome profiling suggests that this association is important for NSD but also for general mRNA turnover. A cryo-electron microscopy structure reveals that the Ski complex binds near the mRNA entry site of the 40S subunit, facilitating the threading of the mRNA into the Ski2 helicase. Collectively, these results demonstrate an unanticipated role for the Ski complex in mRNA decay of ribosome-associated mRNAs, mediated by a direct interaction with the translation machinery.
2017-02-10 | GSE70259 | GEO
Project description:MicroRNAs regulate gene expression through deadenylation, repression and mRNA decay. However, the contribution of each mechanism in non-steady-state situations remains unclear. We monitored the impact of miR-430 on ribosome occupancy of endogenous mRNAs in wild type and dicer mutants lacking mature miR-430. Our results indicate that miR-430 reduces the number of ribosomes on target mRNAs before causing mRNA decay. Translational repression occurs before complete deadenylation, and disrupting deadenylation using an internal poly(A) tail did not block target repression. Finally, we observe that ribosome density along the length of the target mRNA remains constant, suggesting that translational repression occurs by reducing the initiation rate rather than reducing elongation or causing ribosomal drop-off. In summary, our results show that miR-430 regulates translation initiation before inducing mRNA decay.
2012-03-15 | GSE34743 | GEO
Project description:Upf1, Upf2, and Upf3 are the central regulators of nonsense-mediated mRNA decay (NMD), the eukaryotic mRNA quality control pathway generally triggered when a premature termination codon is recognized by the ribosome. The NMD-related functions of the Upf proteins likely commence while these factors are ribosome-associated, but little is known of the timing of their ribosome binding, their specificity for ribosomes translating NMD substrates, or the nature and role of any ribosome:Upf complexes. Here, we have elucidated details of the ribosome-associated steps of NMD. By combining yeast genetics with selective ribosome profiling and co-sedimentation analyses of polysomes with wild-type and mutant Upf proteins, our approaches have identified distinct states of ribosome:Upf association. All three Upf factors manifest progressive polysome association as mRNA translation proceeds, but these events appear to be preceded by formation of a Upf1:80S complex as mRNAs initiate translation. This complex is likely executing an early mRNA surveillance function.
2022-10-21 | PXD029577 | Pride