201
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Clayton CE. Networks of gene expression regulation in Trypanosoma brucei. Mol Biochem Parasitol 2014; 195:96-106. [PMID: 24995711 DOI: 10.1016/j.molbiopara.2014.06.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 06/19/2014] [Accepted: 06/23/2014] [Indexed: 10/25/2022]
Abstract
Regulation of gene expression in Kinetoplastids relies mainly on post-transcriptional mechanisms. Recent high-throughput analyses, combined with mathematical modelling, have demonstrated possibilities for transcript-specific regulation at every stage: trans splicing, polyadenylation, translation, and degradation of both the precursor and the mature mRNA. Different mRNA degradation pathways result in different types of degradation kinetics. The original idea that the fate of an mRNA - or even just its degradation kinetics - can be defined by a single "regulatory element" is an over-simplification. It is now clear that every mRNA can bind many different proteins, some of which may compete with each other. Superimposed upon this complexity are the interactions of those proteins with effectors of gene expression. The amount of protein that is made from a gene is therefore determined by a complex network of interactions.
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Affiliation(s)
- C E Clayton
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany.
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202
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Ryno LM, Genereux J, Naito T, Morimoto RI, Powers ET, Shoulders MD, Wiseman RL. Characterizing the altered cellular proteome induced by the stress-independent activation of heat shock factor 1. ACS Chem Biol 2014; 9:1273-83. [PMID: 24689980 PMCID: PMC4076015 DOI: 10.1021/cb500062n] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Accepted: 04/01/2014] [Indexed: 01/18/2023]
Abstract
The heat shock response is an evolutionarily conserved, stress-responsive signaling pathway that adapts cellular proteostasis in response to pathologic insult. In metazoans, the heat shock response primarily functions through the posttranslational activation of heat shock factor 1 (HSF1), a stress-responsive transcription factor that induces the expression of cytosolic proteostasis factors including chaperones, cochaperones, and folding enzymes. HSF1 is a potentially attractive therapeutic target to ameliorate pathologic imbalances in cellular proteostasis associated with human disease, although the underlying impact of stress-independent HSF1 activation on cellular proteome composition remains to be defined. Here, we employ a highly controllable, ligand-regulated HSF1 that activates HSF1 to levels compatible with those that could be achieved using selective small molecule HSF1 activators. Using a combination of RNAseq and quantitative proteomics, we define the impact of stress-independent HSF1 activation on the composition of the cellular proteome. We show that stress-independent HSF1 activation selectively remodels cytosolic proteostasis pathways without globally influencing the composition of the cellular proteome. Furthermore, we show that stress-independent HSF1 activation decreases intracellular aggregation of a model polyglutamine-containing protein and reduces the cellular toxicity of environmental toxins like arsenite that disrupt cytosolic proteostasis. Collectively, our results reveal a proteome-level view of stress-independent HSF1 activation, providing a framework to establish therapeutic approaches to correct pathologic imbalances in cellular proteostasis through the selective targeting of HSF1.
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Affiliation(s)
- Lisa M. Ryno
- Department
of Molecular & Experimental Medicine, Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Joseph
C. Genereux
- Department
of Molecular & Experimental Medicine, Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Tadasuke Naito
- Department
of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, Illinois 60208, United States
| | - Richard I. Morimoto
- Department
of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, Illinois 60208, United States
| | - Evan T. Powers
- Department
of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Matthew D. Shoulders
- Department
of Molecular & Experimental Medicine, Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, United States
- Department
of Chemistry, Massachusetts Institute of
Technology, Cambridge, Massachusetts 02139, United States
| | - R. Luke Wiseman
- Department
of Molecular & Experimental Medicine, Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, United States
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203
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Ribosome profiling reveals sequence-independent post-initiation pausing as a signature of translation. Cell Res 2014; 24:842-51. [PMID: 24903108 DOI: 10.1038/cr.2014.74] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 03/30/2014] [Accepted: 04/24/2014] [Indexed: 02/07/2023] Open
Abstract
The journey of a newly synthesized polypeptide starts in the peptidyltransferase center of the ribosome, from where it traverses the exit tunnel. The interior of the ribosome exit tunnel is neither straight nor smooth. How the ribosome dynamics in vivo is influenced by the exit tunnel is poorly understood. Genome-wide ribosome profiling in mammalian cells reveals elevated ribosome density at the start codon and surprisingly the downstream 5th codon position as well. We found that the highly focused ribosomal pausing shortly after initiation is attributed to the geometry of the exit tunnel, as deletion of the loop region from ribosome protein L4 diminishes translational pausing at the 5th codon position. Unexpectedly, the ribosome variant undergoes translational abandonment shortly after initiation, suggesting that there exists an obligatory step between initiation and elongation commitment. We propose that the post-initiation pausing of ribosomes represents an inherent signature of the translation machinery to ensure productive translation.
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204
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Wolff S, Weissman JS, Dillin A. Differential scales of protein quality control. Cell 2014; 157:52-64. [PMID: 24679526 DOI: 10.1016/j.cell.2014.03.007] [Citation(s) in RCA: 177] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 03/06/2014] [Accepted: 03/07/2014] [Indexed: 02/06/2023]
Abstract
Proteins are notorious for their unpleasant behavior-continually at risk of misfolding, collecting damage, aggregating, and causing toxicity and disease. To counter these challenges, cells have evolved elaborate chaperone and quality control networks that can resolve damage at the level of the protein, organelle, cell, or tissue. On the smallest scale, the integrity of individual proteins is monitored during their synthesis. On a larger scale, cells use compartmentalized defenses and networks of communication, capable sometimes of signaling between cells, to respond to changes in the proteome's health. Together, these layered defenses help protect cells from damaged proteins.
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Affiliation(s)
- Suzanne Wolff
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Jonathan S Weissman
- Department of Cellular and Molecular Pharmacology, California Institute of Quantitative Biology, Center for RNA Systems Biology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94158, USA.
| | - Andrew Dillin
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA.
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205
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Chang CY, Lin WD, Tu SL. Genome-Wide Analysis of Heat-Sensitive Alternative Splicing in Physcomitrella patens. PLANT PHYSIOLOGY 2014; 165:826-840. [PMID: 24777346 PMCID: PMC4044832 DOI: 10.1104/pp.113.230540] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Plant growth and development are constantly influenced by temperature fluctuations. To respond to temperature changes, different levels of gene regulation are modulated in the cell. Alternative splicing (AS) is a widespread mechanism increasing transcriptome complexity and proteome diversity. Although genome-wide studies have revealed complex AS patterns in plants, whether AS impacts the stress defense of plants is not known. We used heat shock (HS) treatments at nondamaging temperature and messenger RNA sequencing to obtain HS transcriptomes in the moss Physcomitrella patens. Data analysis identified a significant number of novel AS events in the moss protonema. Nearly 50% of genes are alternatively spliced. Intron retention (IR) is markedly repressed under elevated temperature but alternative donor/acceptor site and exon skipping are mainly induced, indicating differential regulation of AS in response to heat stress. Transcripts undergoing heat-sensitive IR are mostly involved in specific functions, which suggests that plants regulate AS with transcript specificity under elevated temperature. An exonic GAG-repeat motif in these IR regions may function as a regulatory cis-element in heat-mediated AS regulation. A conserved AS pattern for HS transcription factors in P. patens and Arabidopsis (Arabidopsis thaliana) reveals that heat regulation for AS evolved early during land colonization of green plants. Our results support that AS of specific genes, including key HS regulators, is fine-tuned under elevated temperature to modulate gene regulation and reorganize metabolic processes.
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Affiliation(s)
- Chiung-Yun Chang
- Institute of Plant and Microbial Biology (C.-Y.C., W.-D.L., S.-L.T.) and Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program (C.-Y.C., S.-L.T.), Academia Sinica, Taipei 11529, Taiwan; andGraduate Institute of Biotechnology (C.-Y.C.) and Biotechnology Center (S.-L.T.), National Chung-Hsing University, Taichung 402, Taiwan
| | - Wen-Dar Lin
- Institute of Plant and Microbial Biology (C.-Y.C., W.-D.L., S.-L.T.) and Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program (C.-Y.C., S.-L.T.), Academia Sinica, Taipei 11529, Taiwan; andGraduate Institute of Biotechnology (C.-Y.C.) and Biotechnology Center (S.-L.T.), National Chung-Hsing University, Taichung 402, Taiwan
| | - Shih-Long Tu
- Institute of Plant and Microbial Biology (C.-Y.C., W.-D.L., S.-L.T.) and Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program (C.-Y.C., S.-L.T.), Academia Sinica, Taipei 11529, Taiwan; andGraduate Institute of Biotechnology (C.-Y.C.) and Biotechnology Center (S.-L.T.), National Chung-Hsing University, Taichung 402, Taiwan
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206
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Shalgi R, Hurt JA, Lindquist S, Burge CB. Widespread inhibition of posttranscriptional splicing shapes the cellular transcriptome following heat shock. Cell Rep 2014; 7:1362-1370. [PMID: 24857664 DOI: 10.1016/j.celrep.2014.04.044] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Revised: 03/13/2014] [Accepted: 04/21/2014] [Indexed: 10/25/2022] Open
Abstract
During heat shock and other proteotoxic stresses, cells regulate multiple steps in gene expression in order to globally repress protein synthesis and selectively upregulate stress response proteins. Splicing of several mRNAs is known to be inhibited during heat stress, often meditated by SRp38, but the extent and specificity of this effect have remained unclear. Here, we examined splicing regulation genome-wide during heat shock in mouse fibroblasts. We observed widespread retention of introns in transcripts from ∼1,700 genes, which were enriched for tRNA synthetase, nuclear pore, and spliceosome functions. Transcripts with retained introns were largely nuclear and untranslated. However, a group of 580+ genes biased for oxidation reduction and protein folding functions continued to be efficiently spliced. Interestingly, these unaffected transcripts are mostly cotranscriptionally spliced under both normal and stress conditions, whereas splicing-inhibited transcripts are mostly spliced posttranscriptionally. Altogether, our data demonstrate widespread repression of splicing in the mammalian heat stress response, disproportionately affecting posttranscriptionally spliced genes.
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Affiliation(s)
- Reut Shalgi
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Jessica A Hurt
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Susan Lindquist
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Christopher B Burge
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
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207
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D'Onofrio DJ, Abel DL. Redundancy of the genetic code enables translational pausing. Front Genet 2014; 5:140. [PMID: 24904640 PMCID: PMC4033003 DOI: 10.3389/fgene.2014.00140] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Accepted: 04/28/2014] [Indexed: 11/13/2022] Open
Abstract
The codon redundancy (“degeneracy”) found in protein-coding regions of mRNA also prescribes Translational Pausing (TP). When coupled with the appropriate interpreters, multiple meanings and functions are programmed into the same sequence of configurable switch-settings. This additional layer of Ontological Prescriptive Information (PIo) purposely slows or speeds up the translation-decoding process within the ribosome. Variable translation rates help prescribe functional folding of the nascent protein. Redundancy of the codon to amino acid mapping, therefore, is anything but superfluous or degenerate. Redundancy programming allows for simultaneous dual prescriptions of TP and amino acid assignments without cross-talk. This allows both functions to be coincident and realizable. We will demonstrate that the TP schema is a bona fide rule-based code, conforming to logical code-like properties. Second, we will demonstrate that this TP code is programmed into the supposedly degenerate redundancy of the codon table. We will show that algorithmic processes play a dominant role in the realization of this multi-dimensional code.
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Affiliation(s)
- David J D'Onofrio
- Control Systems Modeling and Simulation, General Dynamics Sterling Heights, MI, USA ; Department of Humanities and Science, Math Department, College of Humanities and Science, University of Phoenix Detroit, MI, USA
| | - David L Abel
- Department of ProtoBioCybernetics/ProtoBioSemiotics, The Gene Emergence Project of The Origin of Life Science Foundation, Inc. Greenbelt, MD, USA
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208
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Panasenko OO. The role of the E3 ligase Not4 in cotranslational quality control. Front Genet 2014; 5:141. [PMID: 24904641 PMCID: PMC4032911 DOI: 10.3389/fgene.2014.00141] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 04/28/2014] [Indexed: 12/04/2022] Open
Abstract
Cotranslational quality control (QC) is the mechanism by which the cell checks the integrity of newly synthesized proteins and mRNAs. In the event of mistakes these molecules are degraded. The Ccr4-Not complex has been proposed to play a role in this process. It contains both deadenylation and ubiquitination activities, thus it may target both aberrant proteins and mRNAs. Deadenylation is the first step in mRNA degradation. In yeast it is performed by the Ccr4 subunit of the Ccr4-Not complex. Another complex subunit, namely Not4, is a RING E3 ligase and it provides the ubiquitination activity of the complex. It was found associated with translating ribosomes. Thus, it has been suggested that Not4 is involved in ribosome-associated ubiquitination and degradation of aberrant peptides. However, several other E3 ligases have been associated with peptide ubiquitination on the ribosome and the relevance of Not4 in this process remains unclear. In this review we summarize the recent data and suggest a role for Not4 in cotranslational protein QC.
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Affiliation(s)
- Olesya O Panasenko
- Department of Microbiology and Molecular Medicine, Institute of Genetics and Genomics of Geneva - University Medical Center, Faculty of Medicine, University of Geneva Geneva, Switzerland
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209
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Translational control of immune responses: from transcripts to translatomes. Nat Immunol 2014; 15:503-11. [DOI: 10.1038/ni.2891] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Accepted: 04/08/2014] [Indexed: 12/13/2022]
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210
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Hypochlorite-induced structural modifications enhance the chaperone activity of human α2-macroglobulin. Proc Natl Acad Sci U S A 2014; 111:E2081-90. [PMID: 24799681 DOI: 10.1073/pnas.1403379111] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Hypochlorite, an oxidant generated in vivo by the innate immune system, kills invading pathogens largely by inducing the misfolding of microbial proteins. Concomitantly, the nonspecific activity of hypochlorite also damages host proteins, and the accumulation of damaged (misfolded) proteins is implicated in the pathology of a variety of debilitating human disorders (e.g., Alzheimer's disease, atherosclerosis, and arthritis). It is well-known that cells respond to oxidative stress by up-regulating proteostasis machinery, but the direct activation of mammalian chaperones by hypochlorite has not, to our knowledge, been previously reported. In this study, we show that hypochlorite-induced modifications of human α2-macroglobulin (α2M) markedly increase its chaperone activity by generating species, particularly dimers formed by dissociation of the native tetramer, which have enhanced surface hydrophobicity. Moreover, dimeric α2M is generated in whole-blood plasma in the presence of physiologically relevant amounts of hypochlorite. The chaperone activity of hypochlorite-modified α2M involves the formation of stable soluble complexes with misfolded client proteins, including heat-denatured enzymes, oxidized fibrinogen, oxidized LDL, and native or oxidized amyloid β-peptide (Aβ1-42). Here, we show that hypochlorite-modified α2M delivers its misfolded cargo to lipoprotein receptors on macrophages and reduces Aβ1-42 neurotoxicity. Our results support the conclusion that α2M is a specialized chaperone that prevents the extracellular accumulation of misfolded and potentially pathogenic proteins, particularly during innate immune system activity.
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211
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Arnsburg K, Kirstein-Miles J. Interrelation between protein synthesis, proteostasis and life span. Curr Genomics 2014; 15:66-75. [PMID: 24653664 PMCID: PMC3958960 DOI: 10.2174/1389202915666140210210542] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 02/06/2014] [Accepted: 02/06/2014] [Indexed: 12/15/2022] Open
Abstract
The production of newly synthesized proteins is a key process of protein homeostasis that initiates the biosynthetic flux of proteins and thereby determines the composition, stability and functionality of the proteome. Protein synthesis is highly regulated on multiple levels to adapt the proteome to environmental and physiological challenges such as aging and proteotoxic conditions. Imbalances of protein folding conditions are sensed by the cell that then trigger a cascade of signaling pathways aiming to restore the protein folding equilibrium. One regulatory node to rebalance proteostasis upon stress is the control of protein synthesis itself. Translation is reduced as an immediate response to perturbations of the protein folding equilibrium that can be observed in the cytosol as well as in the organelles such as the endoplasmatic reticulum and mitochondria. As reduction of protein synthesis is linked to life span increase, the signaling pathways regu-lating protein synthesis might be putative targets for treatments of age-related diseases. Eukaryotic cells have evolved a complex system for protein synthesis regulation and this review will summarize cellular strategies to regulate mRNA translation upon stress and its impact on longevity.
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Affiliation(s)
- Kristin Arnsburg
- Leibniz-Institut für Molekulare Pharmakologie im Forschungsverbund Berlin e.V. Robert-Rössle-Straße 10; 13125 Berlin, Germany
| | - Janine Kirstein-Miles
- Leibniz-Institut für Molekulare Pharmakologie im Forschungsverbund Berlin e.V. Robert-Rössle-Straße 10; 13125 Berlin, Germany
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212
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Proteostasis and aging of stem cells. Trends Cell Biol 2014; 24:161-70. [DOI: 10.1016/j.tcb.2013.09.002] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 09/04/2013] [Accepted: 09/04/2013] [Indexed: 12/13/2022]
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213
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Gandin V, Topisirovic I. Co-translational mechanisms of quality control of newly synthesized polypeptides. ACTA ACUST UNITED AC 2014; 2:e28109. [PMID: 26779401 PMCID: PMC4705825 DOI: 10.4161/trla.28109] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 12/30/2013] [Accepted: 02/04/2014] [Indexed: 01/23/2023]
Abstract
During protein synthesis, nascent polypeptides emerge from ribosomes to fold into functional proteins. Misfolding of newly synthesized polypeptides (NSPs) at this stage leads to their aggregation. These misfolded NSPs must be expediently cleared to circumvent the deleterious effects of protein aggregation on cell physiology. To this end, a sizable portion of NSPs are ubiquitinated and rapidly degraded by the proteasome. This suggests the existence of co-translational mechanisms that play a pivotal role in the quality control of NSPs. It is generally thought that ribosomes play a central role in this process. During mRNA translation, ribosomes sense errors that lead to the accumulation of aberrant polypeptides, and serve as a hub for protein complexes that are required for optimal folding and/or proteasome-dependent degradation of misfolded polypeptides. In this review, we discuss recent findings that shed light on the molecular underpinnings of the co-translational quality control of NSPs.
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Affiliation(s)
- Valentina Gandin
- Lady Davis Institute for Medical Research; Sir Mortimer B. Davis-Jewish General Hospital; Montréal, QC Canada; Department of Oncology; McGill University; Montréal, QC Canada
| | - Ivan Topisirovic
- Lady Davis Institute for Medical Research; Sir Mortimer B. Davis-Jewish General Hospital; Montréal, QC Canada; Department of Oncology; McGill University; Montréal, QC Canada
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214
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Ribosome profiling: new views of translation, from single codons to genome scale. Nat Rev Genet 2014; 15:205-13. [PMID: 24468696 DOI: 10.1038/nrg3645] [Citation(s) in RCA: 420] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Genome-wide analyses of gene expression have so far focused on the abundance of mRNA species as measured either by microarray or, more recently, by RNA sequencing. However, neither approach provides information on protein synthesis, which is the true end point of gene expression. Ribosome profiling is an emerging technique that uses deep sequencing to monitor in vivo translation. Studies using ribosome profiling have already provided new insights into the identity and the amount of proteins that are produced by cells, as well as detailed views into the mechanism of protein synthesis itself.
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215
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Halter D, Collart MA, Panasenko OO. The Not4 E3 ligase and CCR4 deadenylase play distinct roles in protein quality control. PLoS One 2014; 9:e86218. [PMID: 24465968 PMCID: PMC3895043 DOI: 10.1371/journal.pone.0086218] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 12/08/2013] [Indexed: 11/21/2022] Open
Abstract
Eukaryotic cells control their proteome by regulating protein production and protein clearance. Protein production is determined to a large extent by mRNA levels, whereas protein degradation depends mostly upon the proteasome. Dysfunction of the proteasome leads to the accumulation of non-functional proteins that can aggregate, be toxic for the cell, and, in extreme cases, lead to cell death. mRNA levels are controlled by their rates of synthesis and degradation. Recent evidence indicates that these rates have oppositely co-evolved to ensure appropriate mRNA levels. This opposite co-evolution has been correlated with the mutations in the Ccr4-Not complex. Consistently, the deadenylation enzymes responsible for the rate-limiting step in eukaryotic mRNA degradation, Caf1 and Ccr4, are subunits of the Ccr4-Not complex. Another subunit of this complex is a RING E3 ligase, Not4. It is essential for cellular protein solubility and has been proposed to be involved in co-translational quality control. An open question has been whether this role of Not4 resides strictly in the regulation of the deadenylation module of the Ccr4-Not complex. However, Not4 is important for proper assembly of the proteasome, and the Ccr4-Not complex may have multiple functional modules that participate in protein quality control in different ways. In this work we studied how the functions of the Caf1/Ccr4 and Not4 modules are connected. We concluded that Not4 plays a role in protein quality control independently of the Ccr4 deadenylase, and that it is involved in clearance of aberrant proteins at least in part via the proteasome.
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Affiliation(s)
- David Halter
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, Institute of Genetics and Genomics of Geneva, University of Geneva, Geneva, Switzerland
| | - Martine A. Collart
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, Institute of Genetics and Genomics of Geneva, University of Geneva, Geneva, Switzerland
| | - Olesya O. Panasenko
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, Institute of Genetics and Genomics of Geneva, University of Geneva, Geneva, Switzerland
- * E-mail:
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216
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A comprehensive tRNA deletion library unravels the genetic architecture of the tRNA pool. PLoS Genet 2014; 10:e1004084. [PMID: 24453985 PMCID: PMC3894157 DOI: 10.1371/journal.pgen.1004084] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 11/19/2013] [Indexed: 12/19/2022] Open
Abstract
Deciphering the architecture of the tRNA pool is a prime challenge in translation research, as tRNAs govern the efficiency and accuracy of the process. Towards this challenge, we created a systematic tRNA deletion library in Saccharomyces cerevisiae, aimed at dissecting the specific contribution of each tRNA gene to the tRNA pool and to the cell's fitness. By harnessing this resource, we observed that the majority of tRNA deletions show no appreciable phenotype in rich medium, yet under more challenging conditions, additional phenotypes were observed. Robustness to tRNA gene deletion was often facilitated through extensive backup compensation within and between tRNA families. Interestingly, we found that within tRNA families, genes carrying identical anti-codons can contribute differently to the cellular fitness, suggesting the importance of the genomic surrounding to tRNA expression. Characterization of the transcriptome response to deletions of tRNA genes exposed two disparate patterns: in single-copy families, deletions elicited a stress response; in deletions of genes from multi-copy families, expression of the translation machinery increased. Our results uncover the complex architecture of the tRNA pool and pave the way towards complete understanding of their role in cell physiology.
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217
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ER stress protection in cancer cells: the multifaceted role of the heat shock protein TRAP1. ENDOPLASMIC RETICULUM STRESS IN DISEASES 2014. [DOI: 10.2478/ersc-2014-0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AbstractTRAP1 is an HSP90 chaperone, upregulated in human cancers and involved in organelles’ homeostasis and tumor cell metabolism. Indeed, TRAP1 is a key regulator of adaptive responses used by highly proliferative tumors to face the metabolic stress induced by increased demand of protein synthesis and hostile environments. Besides well-characterized roles in prevention of mitochondrial permeability transition pore opening and in regulating mitochondrial respiration, TRAP1 is involved in novel regulatory mechanisms: i) the attenuation of global protein synthesis, ii) the co-translational regulation of protein synthesis and ubiquitination of specific client proteins, and iii) the protection from Endoplasmic Reticulum stress. This provides a crucial role to TRAP1 in maintaining cellular homeostasis through protein quality control, by avoiding the accumulation of damaged or misfolded proteins and, likely, facilitating the synthesis of selective cancer-related proteins. Herein, we summarize how these regulatory mechanisms are part of an integrated network, which enables cancer cells to modulate their metabolism and to face, at the same time, oxidative and metabolic stress, oxygen and nutrient deprivation, increased demand of energy production and macromolecule biosynthesis. The possibility to undertake a new strategy to disrupt such networks of integrated control in cancer cells holds great promise for treatment of human malignancies.
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218
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Liu B, Qian SB. Translational reprogramming in cellular stress response. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 5:301-15. [PMID: 24375939 DOI: 10.1002/wrna.1212] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Revised: 11/05/2013] [Accepted: 11/07/2013] [Indexed: 01/19/2023]
Abstract
Cell survival in changing environments requires appropriate regulation of gene expression, including translational control. Multiple stress signaling pathways converge on several key translation factors, such as eIF4F and eIF2, and rapidly modulate messenger RNA (mRNA) translation at both the initiation and the elongation stages. Repression of global protein synthesis is often accompanied with selective translation of mRNAs encoding proteins that are vital for cell survival and stress recovery. The past decade has seen significant progress in our understanding of translational reprogramming in part due to the development of technologies that allow the dissection of the interplay between mRNA elements and corresponding binding proteins. Recent genome-wide studies using ribosome profiling have revealed unprecedented proteome complexity and flexibility through alternative translation, raising intriguing questions about stress-induced translational reprogramming. Many surprises emerged from these studies, including wide-spread alternative translation initiation, ribosome pausing during elongation, and reversible modification of mRNAs. Elucidation of the regulatory mechanisms underlying translational reprogramming will ultimately lead to the development of novel therapeutic strategies for human diseases.
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Affiliation(s)
- Botao Liu
- Graduate Field of Genetics, Genomics, and Development, Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
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219
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Chu D, Kazana E, Bellanger N, Singh T, Tuite MF, von der Haar T. Translation elongation can control translation initiation on eukaryotic mRNAs. EMBO J 2013; 33:21-34. [PMID: 24357599 DOI: 10.1002/embj.201385651] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Synonymous codons encode the same amino acid, but differ in other biophysical properties. The evolutionary selection of codons whose properties are optimal for a cell generates the phenomenon of codon bias. Although recent studies have shown strong effects of codon usage changes on protein expression levels and cellular physiology, no translational control mechanism is known that links codon usage to protein expression levels. Here, we demonstrate a novel translational control mechanism that responds to the speed of ribosome movement immediately after the start codon. High initiation rates are only possible if start codons are liberated sufficiently fast, thus accounting for the observation that fast codons are overrepresented in highly expressed proteins. In contrast, slow codons lead to slow liberation of the start codon by initiating ribosomes, thereby interfering with efficient translation initiation. Codon usage thus evolved as a means to optimise translation on individual mRNAs, as well as global optimisation of ribosome availability.
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Affiliation(s)
- Dominique Chu
- School of Computing, University of Kent, Canterbury, UK
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220
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Michel AM, Fox G, M Kiran A, De Bo C, O'Connor PBF, Heaphy SM, Mullan JPA, Donohue CA, Higgins DG, Baranov PV. GWIPS-viz: development of a ribo-seq genome browser. Nucleic Acids Res 2013; 42:D859-64. [PMID: 24185699 PMCID: PMC3965066 DOI: 10.1093/nar/gkt1035] [Citation(s) in RCA: 175] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
We describe the development of GWIPS-viz (http://gwips.ucc.ie), an online genome browser for viewing ribosome profiling data. Ribosome profiling (ribo-seq) is a recently developed technique that provides genome-wide information on protein synthesis (GWIPS) in vivo. It is based on the deep sequencing of ribosome-protected messenger RNA (mRNA) fragments, which allows the ribosome density along all mRNA transcripts present in the cell to be quantified. Since its inception, ribo-seq has been carried out in a number of eukaryotic and prokaryotic organisms. Owing to the increasing interest in ribo-seq, there is a pertinent demand for a dedicated ribo-seq genome browser. GWIPS-viz is based on The University of California Santa Cruz (UCSC) Genome Browser. Ribo-seq tracks, coupled with mRNA-seq tracks, are currently available for several genomes: human, mouse, zebrafish, nematode, yeast, bacteria (Escherichia coli K12, Bacillus subtilis), human cytomegalovirus and bacteriophage lambda. Our objective is to continue incorporating published ribo-seq data sets so that the wider community can readily view ribosome profiling information from multiple studies without the need to carry out computational processing.
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Affiliation(s)
- Audrey M Michel
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland, School of Medicine & Medical Science, Conway Institute, University College Dublin, Dublin 4, Ireland and Howest, University College West Flanders, Rijselstraat 5, 8200 Bruges, Belgium
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221
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Sherman MY, Qian SB. Less is more: improving proteostasis by translation slow down. Trends Biochem Sci 2013; 38:585-91. [PMID: 24126073 DOI: 10.1016/j.tibs.2013.09.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 09/04/2013] [Accepted: 09/10/2013] [Indexed: 11/29/2022]
Abstract
Protein homeostasis, or proteostasis, refers to a proper balance between synthesis, maturation, and degradation of cellular proteins. A growing body of evidence suggests that the ribosome serves as a hub for co-translational folding, chaperone interaction, degradation, and stress response. Accordingly, in addition to the chaperone network and proteasome system, the ribosome has emerged as a major factor in protein homeostasis. Recent work revealed that high rates of elongation of translation negatively affect both the fidelity of translation and the co-translational folding of nascent polypeptides. Accordingly, by slowing down translation one can significantly improve protein folding. In this review, we discuss how to target translational processes to improve proteostasis and implications in treating protein misfolding diseases.
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Affiliation(s)
- Michael Y Sherman
- Department of Biochemistry, Boston University Medical School, Boston, MA 02118, USA.
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222
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Spies N, Burge CB, Bartel DP. 3' UTR-isoform choice has limited influence on the stability and translational efficiency of most mRNAs in mouse fibroblasts. Genome Res 2013; 23:2078-90. [PMID: 24072873 PMCID: PMC3847777 DOI: 10.1101/gr.156919.113] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Variation in protein output across the genome is controlled at several levels, but the relative contributions of different regulatory mechanisms remain poorly understood. Here, we obtained global measurements of decay and translation rates for mRNAs with alternative 3′ untranslated regions (3′ UTRs) in murine 3T3 cells. Distal tandem isoforms had slightly but significantly lower mRNA stability and greater translational efficiency than proximal isoforms on average. The diversity of alternative 3′ UTRs also enabled inference and evaluation of both positively and negatively acting cis-regulatory elements. The 3′ UTR elements with the greatest implied influence were microRNA complementary sites, which were associated with repression of 32% and 4% at the stability and translational levels, respectively. Nonetheless, both the decay and translation rates were highly correlated for proximal and distal 3′ UTR isoforms from the same genes, implying that in 3T3 cells, alternative 3′ UTR sequences play a surprisingly small regulatory role compared to other mRNA regions.
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Affiliation(s)
- Noah Spies
- Howard Hughes Medical Institute and Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA
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223
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Udan-Johns M, Bengoechea R, Bell S, Shao J, Diamond MI, True HL, Weihl CC, Baloh RH. Prion-like nuclear aggregation of TDP-43 during heat shock is regulated by HSP40/70 chaperones. Hum Mol Genet 2013; 23:157-70. [PMID: 23962724 DOI: 10.1093/hmg/ddt408] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
TDP-43 aggregation in the cytoplasm or nucleus is a key feature of the pathology of amyotrophic lateral sclerosis and frontotemporal dementia and is observed in numerous other neurodegenerative diseases, including Alzheimer's disease. Despite this fact, the inciting events leading to TDP-43 aggregation remain unclear. We observed that endogenous TDP-43 undergoes reversible aggregation in the nucleus after the heat shock and that this behavior is mediated by the C-terminal prion domain. Substitution of the prion domain from TIA-1 or an authentic yeast prion domain from RNQ1 into TDP-43 can completely recapitulate heat shock-induced aggregation. TDP-43 is constitutively bound to members of the Hsp40/Hsp70 family, and we found that heat shock-induced TDP-43 aggregation is mediated by the availability of these chaperones interacting with the inherently disordered C-terminal prion domain. Finally, we observed that the aggregation of TDP-43 during heat shock led to decreased binding to hnRNPA1, and a change in TDP-43 RNA-binding partners suggesting that TDP-43 aggregation alters its function in response to misfolded protein stress. These findings indicate that TDP-43 shares properties with physiologic prions from yeast, in that self-aggregation is mediated by a Q/N-rich disordered domain, is modulated by chaperone proteins and leads to altered function of the protein. Furthermore, they indicate that TDP-43 aggregation is regulated by chaperone availability, explaining the recurrent observation of TDP-43 aggregates in degenerative diseases of both the brain and muscle where protein homeostasis is disrupted.
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Affiliation(s)
- Maria Udan-Johns
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St Louis, MO 63110, USA
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224
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Comyn SA, Chan GT, Mayor T. False start: cotranslational protein ubiquitination and cytosolic protein quality control. J Proteomics 2013; 100:92-101. [PMID: 23954725 DOI: 10.1016/j.jprot.2013.08.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 08/02/2013] [Accepted: 08/04/2013] [Indexed: 12/18/2022]
Abstract
UNLABELLED Maintaining proteostasis is crucial to cells given the toxic potential of misfolded proteins and aggregates. To this end, cells rely on a number of quality control pathways that survey proteins both during, as well as after synthesis to prevent protein aggregation, promote protein folding, and to target terminally misfolded proteins for degradation. In eukaryotes, the ubiquitin proteasome system plays a critical role in protein quality control by selectively targeting proteins for degradation. Recent studies have added to our understanding of cytosolic protein quality control, particularly in the area of cotranslational protein ubiquitination, and suggest that overlap exists across co- and post-translational protein quality control networks. Here, we review recent advances made in the area of cytoplasmic protein quality control with an emphasis on the pathways involved in cotranslational degradation of eukaryotic cytosolic proteins. BIOLOGICAL SIGNIFICANCE Protein homeostasis, or proteostasis, encompasses the systems required by the cell for the generation and maintenance of the correct levels, conformational state, distribution, and degradation of its proteome. One of the challenges faced by the cell in maintaining proteostasis is the presence of misfolded proteins. Cells therefore have a number of protein quality control pathways to aid in folding or mediate the degradation of misfolded proteins. The ubiquitin proteasome system in particular plays a critical role in protein quality control by selectively targeting proteins for degradation. Nascent polypeptides can be ubiquitinated cotranslationally, however to what extent and how this is used by the cell as a quality control mechanism has, until recently, remained relatively unclear. The picture now emerging is one of two quality control networks: one that recognizes nascent polypeptides on stalled ribosomes and another that targets actively translating polypeptides that misfold, failing to attain their native conformation. These studies underscore the important balance between cotranslational protein folding and degradation in the maintenance of protein homeostasis. In this review we summarize recent advances made in the area of cytoplasmic protein quality control with an emphasis on pathways involved in cotranslational degradation of eukaryotic cytosolic proteins. This article is part of a Special Issue entitled: Can Proteomics Fill the Gap Between Genomics and Phenotypes?
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Affiliation(s)
- Sophie A Comyn
- Department of Biochemistry and Molecular Biology, Center for High-Throughput Biology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Gerard T Chan
- Department of Biochemistry and Molecular Biology, Center for High-Throughput Biology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Thibault Mayor
- Department of Biochemistry and Molecular Biology, Center for High-Throughput Biology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
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225
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Affiliation(s)
- Valentina Gandin
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, and Department of Oncology, McGill University, Montréal, Quebec, H3A 1A3, Canada
| | - Ivan Topisirovic
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, and Department of Oncology, McGill University, Montréal, Quebec, H3A 1A3, Canada
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226
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Kirstein-Miles J, Morimoto RI. Ribosome-associated chaperones act as proteostasis sentinels. Cell Cycle 2013; 12:2335-6. [PMID: 23856581 PMCID: PMC3841305 DOI: 10.4161/cc.25703] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Janine Kirstein-Miles
- Department of Molecular Biosciences; Rice Institute for Biomedical Research; Northwestern University; Evanston, IL USA
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227
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Mateyak MK, Kinzy TG. ADP-ribosylation of translation elongation factor 2 by diphtheria toxin in yeast inhibits translation and cell separation. J Biol Chem 2013; 288:24647-55. [PMID: 23853096 DOI: 10.1074/jbc.m113.488783] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Eukaryotic translation elongation factor 2 (eEF2) facilitates the movement of the peptidyl tRNA-mRNA complex from the A site of the ribosome to the P site during protein synthesis. ADP-ribosylation (ADP(R)) of eEF2 by bacterial toxins on a unique diphthamide residue inhibits its translocation activity, but the mechanism is unclear. We have employed a hormone-inducible diphtheria toxin (DT) expression system in Saccharomyces cerevisiae which allows for the rapid induction of ADP(R)-eEF2 to examine the effects of DT in vivo. ADP(R) of eEF2 resulted in a decrease in total protein synthesis consistent with a defect in translation elongation. Association of eEF2 with polyribosomes, however, was unchanged upon expression of DT. Upon prolonged exposure to DT, cells with an abnormal morphology and increased DNA content accumulated. This observation was specific to DT expression and was not observed when translation elongation was inhibited by other methods. Examination of these cells by electron microscopy indicated a defect in cell separation following mitosis. These results suggest that expression of proteins late in the cell cycle is particularly sensitive to inhibition by ADP(R)-eEF2.
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Affiliation(s)
- Maria K Mateyak
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
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228
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Michel AM, Baranov PV. Ribosome profiling: a Hi-Def monitor for protein synthesis at the genome-wide scale. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 4:473-90. [PMID: 23696005 PMCID: PMC3823065 DOI: 10.1002/wrna.1172] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 04/21/2013] [Accepted: 04/23/2013] [Indexed: 01/28/2023]
Abstract
Ribosome profiling or ribo-seq is a new technique that provides genome-wide information on protein synthesis (GWIPS) in vivo. It is based on the deep sequencing of ribosome protected mRNA fragments allowing the measurement of ribosome density along all RNA molecules present in the cell. At the same time, the high resolution of this technique allows detailed analysis of ribosome density on individual RNAs. Since its invention, the ribosome profiling technique has been utilized in a range of studies in both prokaryotic and eukaryotic organisms. Several studies have adapted and refined the original ribosome profiling protocol for studying specific aspects of translation. Ribosome profiling of initiating ribosomes has been used to map sites of translation initiation. These studies revealed the surprisingly complex organization of translation initiation sites in eukaryotes. Multiple initiation sites are responsible for the generation of N-terminally extended and truncated isoforms of known proteins as well as for the translation of numerous open reading frames (ORFs), upstream of protein coding ORFs. Ribosome profiling of elongating ribosomes has been used for measuring differential gene expression at the level of translation, the identification of novel protein coding genes and ribosome pausing. It has also provided data for developing quantitative models of translation. Although only a dozen or so ribosome profiling datasets have been published so far, they have already dramatically changed our understanding of translational control and have led to new hypotheses regarding the origin of protein coding genes.
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229
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Kirstein-Miles J, Scior A, Deuerling E, Morimoto RI. The nascent polypeptide-associated complex is a key regulator of proteostasis. EMBO J 2013; 32:1451-68. [PMID: 23604074 DOI: 10.1038/emboj.2013.87] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Accepted: 03/18/2013] [Indexed: 11/09/2022] Open
Abstract
The adaptation of protein synthesis to environmental and physiological challenges is essential for cell viability. Here, we show that translation is tightly linked to the protein-folding environment of the cell through the functional properties of the ribosome bound chaperone NAC (nascent polypeptide-associated complex). Under non-stress conditions, NAC associates with ribosomes to promote translation and protein folding. When proteostasis is imbalanced, NAC relocalizes from a ribosome-associated state to protein aggregates in its role as a chaperone. This results in a functional depletion of NAC from the ribosome that diminishes translational capacity and the flux of nascent proteins. Depletion of NAC from polysomes and re-localisation to protein aggregates is observed during ageing, in response to heat shock and upon expression of the highly aggregation-prone polyglutamine-expansion proteins and Aβ-peptide. These results demonstrate that NAC has a central role as a proteostasis sensor to provide the cell with a regulatory feedback mechanism in which translational activity is also controlled by the folding state of the cellular proteome and the cellular response to stress.
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Affiliation(s)
- Janine Kirstein-Miles
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208, USA
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230
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Global translational pausing in response to stress. Nat Rev Genet 2013. [DOI: 10.1038/nrg3420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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