The Greatwall-Endosulfine-PP2A/B55 pathway controls entry into quiescence by promoting translation of Elongator-tuneable transcripts
Ontology highlight
ABSTRACT:
ORGANISM(S): Schizosaccharomyces pombe
PROVIDER: GSE269854 | GEO | 2024/06/17
REPOSITORIES: GEO
Similar Datasets
Project description:The highly conserved eukaryotic Elongator complex performs specific chemical modifications on wobble base uridines of tRNAs, which are essential for proteome stability and homeostasis. The complex is formed by six individual subunits (Elp1-6) that are all equally important for its tRNA modification activity. However, its overall architecture and the detailed reaction mechanism remain elusive. Here, we report the structures of the fully assembled yeast Elongator and the Elp123 sub-complex solved by an integrative structure determination approach showing that two copies of the Elp1, Elp2 and Elp3 subunits form a two-lobed scaffold, which binds Elp456 asymmetrically. Our topological models are consistent with previous studies on individual subunits and further validated by complementary biochemical analyses. Our study provides a structural framework on how the tRNA modification activity is carried out by Elongator.
2016-12-20 | PXD005251 | Pride
Project description:The deposited data concern the mapping of acetylation sites on wild-type and the K280A, Y363A mutants of Elp3 by LC-MS/MS.
Abstract of the manuscript:
tRNA modifications affect ribosomal elongation speed and co-translational folding dynamics. The Elongator complex is responsible for introducing 5-carboxymethyl at wobble uridine bases (cm5U34) in eukaryotic tRNAs. However, the structure and function of human Elongator remain poorly understood. In this study, we present a series of cryo-EM structures of human ELP123 in complex with tRNA and cofactors at four different stages of the reaction cycle. The structures at resolutions of up to 2.9 A together with complementary functional analyses reveal the molecular mechanism of the modification reaction. Our results show that tRNA binding exposes a universally conserved uridine at position 33 (U33), which triggers acetyl-CoA (ACO) hydrolysis. We identify a series of conserved residues that are crucial for the radical-based acetylation of U34 and profile the molecular effects of patient-derived mutations. Together, we provide the first high-resolution view of human Elongator and reveal its detailed mechanism of action.
| MSV000092998 | MassIVE
Project description:Target of Rapamycin Complex 1 (TORC1) signaling promotes growth and ageing. Inhibition of TORC1 leads to a down-regulation of factors that stimulate protein translation, which in turn contributes to longevity. TORC1-dependent post-transcriptional regulation of protein translation has been well studied, while analogous transcriptional regulation is less understood. Here we screened fission yeast deletion mutants for resistance to Torin1, which inhibits TORC1 and cell growth. Cells lacking the GATA transcription factor Gaf1 (gaf1Δ) grew normally even in high doses of Torin1. The gaf1Δ mutation shortened the chronological lifespan of non-dividing cells and diminished the longevity triggered by Torin1 treatment. Expression profiling and genome-wide binding experiments showed that, upon TORC1 inhibition, Gaf1 directly up-regulated genes for small-molecule metabolic pathways and indirectly repressed genes for protein translation. Surprisingly, Gaf1 bound to, and down-regulated the tRNA genes, so also functions as a transcription factor for genes transcribed by RNA polymerase III. Thus, Gaf1 controls the transcription of both coding and tRNA genes to inhibit translation and growth downstream of TORC1.
2020-03-02 | E-MTAB-8569 | biostudies-arrayexpress
Project description:Elongator is a histone acetyltransferase (HAT) complex associated with RNA polymerase II (RNAPII) to facilitate transcription elongation. It consists of subunits Elp1-6, with Elp3 conferring HAT activity. Elongator is conserved in yeast, plants and humans. In humans, mutations in Elp genes cause neuronal diseases. In plants, Elongator is a positive regulator of cell proliferation during leaf and root growth. Consequently, Arabidopsis Elongator mutants (elo) have narrow leaves and short roots; additionally, germination, vegetative growth and reproductive development are also affected. Mutants have altered auxin signaling, and a number of auxin-related genes are among those differentially expressed in the mutant. Only two genes have been confirmed as targeted by Elongator during RNAPII transcription elongation, including the light-regulated auxin response regulator IAA3/SHY2.
2018-01-23 | GSE42053 | GEO
Project description:The highly conserved Elongator complex is a translational regulator and a subject of growing interest due to its critical role in neurodevelopment, neurological diseases and brain tumors. Clinically relevant mutations have been reported in the catalytic Elp123 subcomplex, while no mutation in the accessory subcomplex Elp456 have been described so far. Here, we identify pathogenic variants of ELP4 and ELP6 in patients with developmental delay, epilepsy as well as intellectual and motor impairment. We use single particle cryo-EM to determine the structures of human and murine Elp456 subcomplexes and reconstitute an active mouse Elongator comprising of all six subunits. We show that patient derived mutations in Elp456 affect the affinity for specific tRNA molecules and diminish the tRNA modification activity of Elongator in vitro as well as in human and murine cells. Modelling the mutations in mice recapitulates the clinical features of the patients and reveals neuropathology that differs from the one caused by previously characterized Elp123 mutations. Altogether, our study demonstrates a direct correlation between Elp4 and Elp6 mutations, reduced Elongator activity and neurological defects. Foremost, our data indicate distinct roles of the Elp123 and Elp456 subcomplexes for different tRNA species, in different cell types and in different key steps during the neurodevelopment of higher organisms.
2022-05-17 | PXD032925 | Pride
Project description:We show that the sensitivity of tsc mutant cells to rapamycin is mediated by TORC1 and can be suppressed by overexpression of the 2-oxoglutarate-Fe(II) dependent oxygenase, Isp7. We show that Isp7 is a novel regulator of amino acids uptake that acts via regulation of gene expression, both upstream and downstream of TOR signaling. suppressed by overexpression of the putative 2-oxoglutarate-Fe(II) dependent oxygenase, Isp7. We show that Isp7 is a novel master regulator of amino acids uptake that acts via regulation of gene expression, both upstream and downstream of TOR signaling. TOR proteins reside in two distinct complexes, TOR complex 1 and 2 (TORC1 and TORC2) that are central for the regulation of cellular growth, proliferation and survival. TOR is also the target for the immunosuppressive and anti-cancer drug rapamycin. In Schizosaccharaomyces pombe, disruption of the TSC complex, mutations in which can lead to the Tuberous Sclerosis syndrome in humans, results in a rapamycin sensitive phenotype under poor nitrogen conditions. We show here that the sensitivity to rapamycin is mediated via inhibition of TORC1 and suppressed by overexpression of isp7+, a member of the family of 2-oxoglutarate-Fe(II) dependent oxygenases. The transcript level of isp7+ is negatively regulated by TORC1 but positively regulated by TORC2. Yet, we find extensive similarity between the transcriptome of cells disrupted for isp7+ and cells mutated in the catalytic subunit of TORC1. Moreover, Isp7 regulates amino acid permease expression similarly to TORC1 and in contrast to TORC2. Overexpression of isp7+ induces TORC1-dependent phosphorylation of ribosomal protein Rps6, while inhibiting TORC2-dependent phosphorylation and activation of the AGC-like kinase Gad8. Taken together, our findings suggest a central role for Isp7 in amino acid homeostasis and the presence of isp7+-dependent regulatory loops that affect both TORC1 and TORC2. 6 Samples (arrays) were performed. We generated pairwise comparison between DISP7 and WT, using Partek Genomics Suite. Genes with pâ¤5%[FDR] and a fold-change difference of â¥2\1.5 or <-2\-1.5 were selected.
2014-02-05 | E-GEOD-52759 | biostudies-arrayexpress
Project description:Cancer genomics has illuminated a wide spectrum of genes and core molecular processes contributing to human malignancy. Still, the genetic and molecular basis of many cancers remains only partially explained. Genetic predisposition accounts for 5-10% of cancer diagnoses and genetic events cooperating with known somatic driver events are poorly understood. Analyzing established cancer predisposition genes in medulloblastoma (MB), a malignant childhood brain tumor, we recently identified pathogenic germline variants that account for 5% of all MB patients. Here, by extending our previous analysis to include all protein-coding genes, we discovered and replicated rare germline loss-of-function (LoF) variants across Elongator Complex Protein 1 (ELP1) on 9q31.3 in 15% of pediatric MBSHH cases, thus implicating ELP1 as the most common MB predisposition gene and increasing genetic predisposition to 40% for pediatric MBSHH. Inheritance was verified based on parent-offspring and pedigree analysis, which identified two families with a history of pediatric MB. ELP1-associated MBs were restricted to the molecular SHH subtype and were characterized by universal biallelic inactivation of ELP1 due to somatic loss of chromosome 9q. The majority of ELP1-associated MBs exhibited co-occurring somatic PTCH1 (9q22.32) alterations, suggesting that ELP1-deficiency predisposes to tumor development in combination with constitutive activation of SHH signaling. ELP1 is an essential subunit of the evolutionary conserved Elongator complex, whose primary function is to enable efficient translational elongation through tRNAs modifications at the wobble (U34) position. Biochemical, transcriptional, and proteomic analyses revealed that ELP1-associated MBSHH are characterized by a destabilized core Elongator complex, loss of Elongator-dependent tRNA modifications, codon-dependent translational reprogramming, and induction of the unfolded protein response (UPR), consistent with deregulation of protein homeostasis due to Elongator-deficiency in model systems. Our findings suggest that genetic predisposition to proteome instability is a previously underappreciated determinant in the pathogenesis of pediatric brain cancer. These results provide strong rationale for further investigating the role of protein homeostasis in other pediatric and adult cancer types and potential opportunities for novel therapeutic interference.
2020-04-23 | PXD016832 | Pride
Project description:We show that the sensitivity of tsc mutant cells to rapamycin is mediated by TORC1 and can be suppressed by overexpression of the 2-oxoglutarate-Fe(II) dependent oxygenase, Isp7. We show that Isp7 is a novel regulator of amino acids uptake that acts via regulation of gene expression, both upstream and downstream of TOR signaling. suppressed by overexpression of the putative 2-oxoglutarate-Fe(II) dependent oxygenase, Isp7. We show that Isp7 is a novel master regulator of amino acids uptake that acts via regulation of gene expression, both upstream and downstream of TOR signaling. TOR proteins reside in two distinct complexes, TOR complex 1 and 2 (TORC1 and TORC2) that are central for the regulation of cellular growth, proliferation and survival. TOR is also the target for the immunosuppressive and anti-cancer drug rapamycin. In Schizosaccharaomyces pombe, disruption of the TSC complex, mutations in which can lead to the Tuberous Sclerosis syndrome in humans, results in a rapamycin sensitive phenotype under poor nitrogen conditions. We show here that the sensitivity to rapamycin is mediated via inhibition of TORC1 and suppressed by overexpression of isp7+, a member of the family of 2-oxoglutarate-Fe(II) dependent oxygenases. The transcript level of isp7+ is negatively regulated by TORC1 but positively regulated by TORC2. Yet, we find extensive similarity between the transcriptome of cells disrupted for isp7+ and cells mutated in the catalytic subunit of TORC1. Moreover, Isp7 regulates amino acid permease expression similarly to TORC1 and in contrast to TORC2. Overexpression of isp7+ induces TORC1-dependent phosphorylation of ribosomal protein Rps6, while inhibiting TORC2-dependent phosphorylation and activation of the AGC-like kinase Gad8. Taken together, our findings suggest a central role for Isp7 in amino acid homeostasis and the presence of isp7+-dependent regulatory loops that affect both TORC1 and TORC2.
2014-02-05 | GSE52759 | GEO
Project description:The Target Of Rapamycin (TOR) protein is a Ser/Thr kinase that functions in two distinct multiprotein complexes: TORC1 and TORC2. These conserved complexes regulate many different aspects of cell growth in response to intra- and extracellular cues. Here we report the first bona fide substrate of yeast TORC1: the AGC-kinase Sch9. Six amino acids in the c-terminus of Sch9 are directly phosphorylated by TORC1. Phosphorylation of these residues is lost upon rapamycin-treatment as well as carbon- or nitrogen-starvation and transiently reduced following application of osmotic, oxidative or thermal stress. TORC1-dependent phosphorylation is required for Sch9 activity and replacement of residues phosphorylated by TORC1 with Asp/Glu renders Sch9 activity TORC1-independent. Sch9 is required for TORC1 to properly regulate ribosome biogenesis, translation initiation and entry into G0 phase, but not expression of Gln3-dependent genes. Our results suggest that Sch9 functions analogously to the mammalian TORC1 substrate S6K1 rather than the mTORC2 substrate PKB/Akt. Keywords: time course, cell type.
2007-04-28 | GSE7660 | GEO
Project description:A stochastic simulation of yeast translation using Total Asymmetric Simple Exclusion Principle (TASEP) principles, representing ribosomes, tRNAs, mRNAs, and a tRNA re-charging process involving aminoacyl tRNA synthetases
2020-02-05 | MODEL2001080004 | BioModels