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Escobar-Pacheco M, Luna-Álvarez M, Dávila-Ortiz de Montellano D, Yescas-Gómez P, Ramírez-García MÁ. Ovarioleukodystrophy Due to EIF2B Genes: Systematic Review and Case Report. Cureus 2024; 16:e64497. [PMID: 39139316 PMCID: PMC11319890 DOI: 10.7759/cureus.64497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/12/2024] [Indexed: 08/15/2024] Open
Abstract
Leukodystrophies comprise a spectrum of genetic disorders affecting white matter (WM) formation in the central nervous system (CNS), of which vanishing white matter disease (VWMD) is one. VWMD presents with progressive neurological deterioration and a variety of manifestations. Ovarioleukodystrophy, a subtype of VWMD, exhibits a distinctive clinical profile encompassing both CNS WM alterations and ovarian dysfunction. Variants in genes of the eukaryotic translation initiation factor 2B (EIF2B) complex affect the full form and are implicated in VWMD, including ovarioleukodystrophy. This work aimed to systematically review all published cases of ovarioleukodystrophy associated with variants in the EIF2B1-5 gene complex based on the first case identified in a Mexican population. We performed a systematic review according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines of published cases of ovarioleukodystrophy associated with the EIF2B gene complex, including a newly identified case from Mexico. We identified 207 publications using PUBMED, SCOPUS, and PMC databases. One hundred fifty-one publications were eliminated due to duplicates, titles, abstracts, or other reasons, while 56 publications were revised, of which 29 were eliminated because they dealt with other genes or non-human research, and 27 reports were assessed for eligibility. Finally, 14 reports describing ovarian involvement, neuroimaging, and molecular variants were included. Our review identified 20 cases worldwide, with a median age of onset of 19 years. Clinical features included WM involvement, ovarian abnormalities, gait disturbances, epilepsy, cognitive and language impairment, and other neurological manifestations. Neuroimaging showed characteristic WM changes, highlighting the importance of MRI in diagnosis. Missense variants predominated among the identified genetic mutations, especially in the EIF2B4 and EIF2B5 genes. Ovarioleukodystrophy is an ultra-rare disorder with a wide range of clinical manifestations and ovarian changes. Gynecological evaluation is crucial in suspected cases of ovarioleukodystrophy, as ovarian manifestations may precede neurological symptoms. The role of MRI is crucial in the diagnostic approach to this entity. Continued collaborative efforts are essential to elucidate genotype-phenotype correlations, improve clinical management, and promote therapeutic advances for this rare disorder.
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Affiliation(s)
- Mariana Escobar-Pacheco
- Genetics, National Institute of Neurology and Neurosurgery Manuel Velasco Suárez, Mexico City, MEX
| | - Mariana Luna-Álvarez
- Genetics, National Institute of Neurology and Neurosurgery Manuel Velasco Suárez, Mexico City, MEX
- Genetics, National Institute of Pediatrics, Mexico City, MEX
| | | | - Petra Yescas-Gómez
- Genetics, National Institute of Neurology and Neurosurgery Manuel Velasco Suárez, Mexico City, MEX
| | - Miguel Á Ramírez-García
- Genetics, National Institute of Neurology and Neurosurgery Manuel Velasco Suárez, Mexico City, MEX
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Das S, Ray BK, Chakraborty U, Tippabathani J, Santra A. The Coexistence of Two Genetic Astrocytopathies-Megalencephalic Leukoencephalopathy and Vanishing White Matter Disease-in an Indian Child. Neuropediatrics 2023; 54:153-156. [PMID: 36878222 DOI: 10.1055/s-0042-1760367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Abstract
A 9-month-old male child, born of second-degree consanguinity, presented with a progressively enlarging head since early infancy. The child had normal early development, but further acquisition of milestones after 6 months was delayed. He had afebrile seizures at 9 months, followed by the appearance of appendicular spasticity. First magnetic resonance imaging (MRI) showed nonenhancing, diffuse, bilaterally symmetrical T1/fluid-attenuated inversion recovery (FLAIR) hypointensity and T2 hyperintensity of the cerebral white matter and anterior temporal cysts. Subsequently, the periventricular and deep white matter developed microcystic changes with a pattern of radial stripes. Next-generation sequencing revealed homozygous autosomal recessive variations in the MLC1 gene [c.188T > G, (p.Leu63Arg)] on exon 3 and also in the EIF2B3 gene [c.674G > A, (p.Arg225Gln)] on exon 7, the parents being heterozygous carriers for both variations. This article highlights the rare occurrence of two leukodystrophies of diverse pathogenesis in a child from a nonpredisposed community.
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Affiliation(s)
- Suman Das
- Department of Neuromedicine, Bangur Institute of Neurosciences, Kolkata, West Bengal, India
| | - Biman Kanti Ray
- Department of Neuromedicine, Bangur Institute of Neurosciences, Kolkata, West Bengal, India
| | - Uddalak Chakraborty
- Department of Neuromedicine, Bangur Institute of Neurosciences, Kolkata, West Bengal, India
| | | | - Arindam Santra
- Department of Neuromedicine, Bangur Institute of Neurosciences, Kolkata, West Bengal, India
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Zhang C, Huang Y, Fang C, Liang Y, Jiang D, Li J, Ma H, Jiang W, Feng Y. Construction and validation of a prognostic model based on ten signature cell cycle-related genes for early-stage lung squamous cell carcinoma. Cancer Biomark 2023; 36:313-326. [PMID: 36938730 DOI: 10.3233/cbm-220227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Abstract
BACKGROUND We performed a bioinformatics analysis to screen for cell cycle-related differentially expressed genes (DEGs) and constructed a model for the prognostic prediction of patients with early-stage lung squamous cell carcinoma (LSCC). METHODS From a gene expression omnibus (GEO) database, the GSE157011 dataset was randomly divided into an internal training group and an internal testing group at a 1:1 ratio, and the GSE30219, GSE37745, GSE42127, and GSE73403 datasets were merged as the external validation group. We performed single-sample gene set enrichment analysis (ssGSEA), univariate Cox analysis, and difference analysis, and identified 372 cell cycle-related genes. Additionally, we combined LASSO/Cox regression analysis to construct a prognostic model. Then, patients were divided into high-risk and low-risk groups according to risk scores. The internal testing group, discovery set, and external verification set were used to assess model reliability. We used a nomogram to predict patient prognoses based on clinical features and risk values. Clinical relevance analysis and the Human Protein Atlas (HPA) database were used to verify signature gene expression. RESULTS Ten cell cycle-related DEGs (EIF2B1, FSD1L, FSTL3, ORC3, HMMR, SETD6, PRELP, PIGW, HSD17B6, and GNG7) were identified and a model based on the internal training group constructed. From this, patients in the low-risk group had a higher survival rate when compared with the high-risk group. Time-dependent receiver operating characteristic (tROC) and Cox regression analyses showed the model was efficient and accurate. Clinical relevance analysis and the HPA database showed that DEGs were significantly dysregulated in LSCC tissue. CONCLUSION Our model predicted the prognosis of early-stage LSCC patients and demonstrated potential applications for clinical decision-making and individualized therapy.
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Affiliation(s)
- Chengpeng Zhang
- Department of Thoracic Surgery, Suzhou Ninth People's Hospital, Suzhou, Jiangsu, China.,Department of Thoracic Surgery, Suzhou Ninth People's Hospital, Suzhou, Jiangsu, China
| | - Yong Huang
- Department of Thoracic Surgery, Haimen People's Hospital, Nantong, Jiangsu, China.,Department of Thoracic Surgery, Suzhou Ninth People's Hospital, Suzhou, Jiangsu, China
| | - Chen Fang
- Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.,Department of Thoracic Surgery, Suzhou Ninth People's Hospital, Suzhou, Jiangsu, China
| | - Yingkuan Liang
- Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Dong Jiang
- Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Jiaxi Li
- Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Haitao Ma
- Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Wei Jiang
- Department of Thoracic Surgery, Dushu Lake Hospital Affiliated to Soochow University, Suzhou, Jiangsu, China
| | - Yu Feng
- Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
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The role of eIF2 phosphorylation in cell and organismal physiology: new roles for well-known actors. Biochem J 2022; 479:1059-1082. [PMID: 35604373 DOI: 10.1042/bcj20220068] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/21/2022] [Accepted: 04/25/2022] [Indexed: 02/06/2023]
Abstract
Control of protein synthesis (mRNA translation) plays key roles in shaping the proteome and in many physiological, including homeostatic, responses. One long-known translational control mechanism involves phosphorylation of initiation factor, eIF2, which is catalysed by any one of four protein kinases, which are generally activated in response to stresses. They form a key arm of the integrated stress response (ISR). Phosphorylated eIF2 inhibits eIF2B (the protein that promotes exchange of eIF2-bound GDP for GTP) and thus impairs general protein synthesis. However, this mechanism actually promotes translation of certain mRNAs by virtue of specific features they possess. Recent work has uncovered many previously unknown features of this regulatory system. Several studies have yielded crucial insights into the structure and control of eIF2, including that eIF2B is regulated by several metabolites. Recent studies also reveal that control of eIF2 and the ISR helps determine organismal lifespan and surprising roles in sensing mitochondrial stresses and in controlling the mammalian target of rapamycin (mTOR). The latter effect involves an unexpected role for one of the eIF2 kinases, HRI. Phosphoproteomic analysis identified new substrates for another eIF2 kinase, Gcn2, which senses the availability of amino acids. Several genetic disorders arise from mutations in genes for eIF2α kinases or eIF2B (i.e. vanishing white matter disease, VWM and microcephaly, epileptic seizures, microcephaly, hypogenitalism, diabetes and obesity, MEHMO). Furthermore, the eIF2-mediated ISR plays roles in cognitive decline associated with Alzheimer's disease. New findings suggest potential therapeutic value in interfering with the ISR in certain settings, including VWM, for example by using compounds that promote eIF2B activity.
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Zapater JL, Lednovich KR, Khan MW, Pusec CM, Layden BT. Hexokinase domain-containing protein-1 in metabolic diseases and beyond. Trends Endocrinol Metab 2022; 33:72-84. [PMID: 34782236 PMCID: PMC8678314 DOI: 10.1016/j.tem.2021.10.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 10/11/2021] [Accepted: 10/18/2021] [Indexed: 12/16/2022]
Abstract
Glucose phosphorylation by hexokinases (HKs) traps glucose in cells and facilitates its usage in metabolic processes dependent on cellular needs. HK domain-containing protein-1 (HKDC1) is a recently discovered protein with wide expression containing HK activity, first noted through a genome-wide association study (GWAS) to be linked with gestational glucose homeostasis during pregnancy. Since then, HKDC1 has been observed to be expressed in many human tissues. Moreover, studies have shown that HKDC1 plays a role in glucose homeostasis by which it may affect the progression of many pathophysiological conditions such as gestational diabetes mellitus (GDM), nonalcoholic steatohepatitis (NASH), and cancer. Here, we review the key studies contributing to our current understanding of the roles of HKDC1 in human pathophysiological conditions and potential therapeutic interventions.
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Affiliation(s)
- Joseph L Zapater
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA; Jesse Brown VA Medical Center, Chicago, IL, USA
| | - Kristen R Lednovich
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Md Wasim Khan
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Carolina M Pusec
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Brian T Layden
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA; Jesse Brown VA Medical Center, Chicago, IL, USA.
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Liu C, Miyahara H, Dai J, Cui X, Li Y, Kang X, Higuchi K, Mori M. Involvement of increased endoplasmic reticulum stress in the development of cataracts in BALB.NCT-Cpox nct mice. Exp Eye Res 2021; 215:108905. [PMID: 34968474 DOI: 10.1016/j.exer.2021.108905] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/26/2021] [Accepted: 12/20/2021] [Indexed: 12/12/2022]
Abstract
The BALB.NCT-Cpoxnct is a mutant mouse model for hereditary cataracts. We previously uncovered that the primary cause of the cataracts of BALB.NCT-Cpoxnct is a mutation in the coproporphyrinogen oxidase (Cpox) gene. Because of the mutation, excessive coproporphyrin is accumulated in the BALB.NCT-Cpoxnct lens. In this study, we analyzed the changes in transcriptome and proteins in the lenses of 4- and 12-week-old BALB.NCT-Cpoxnct to further elucidate the molecular etiology of cataracts in this mouse strain. Transcriptome analysis revealed that endoplasmic reticulum (ER) stress was increased in the BALB.NCT-Cpoxnct lens that induced persistent activation of the PERK signaling pathway of the ER stress response. Also, levels of crystallin transcripts and proteins were reduced in the BALB.NCT-Cpoxnct lens. Analysis of proteins disclosed aggregation of crystallins and keratins prior to the manifestation of cataracts in 4-week-old BALB.NCT-Cpoxnct mice. At 12 weeks of age, insoluble crystallins were accumulated in the cataractous BALB.NCT-Cpoxnct lens. Overall, our data suggest the following sequence of events in the BALB.NCT-Cpoxnct lens: accumulated coproporphyrin induces the aggregation of proteins including crystallins. Aggregated proteins increase ER stress that, in turn, leads to the repression of global translation of proteins including crystallins. The decline in the molecular chaperone crystallin aggravates aggregation and insolubilization of proteins. This vicious cycle would eventually lead to cataracts in BALB.NCT-Cpoxnct.
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Affiliation(s)
- Chang Liu
- Department of Aging Biology, Shinshu University Graduate School of Medicine, Science and Technology, 3-1-1 Asahi, Matsumoto, 390-8621, Japan; Department of Respiratory, The Third Hospital of Shijiazhuang, Shijiazhuang, 050011, China.
| | - Hiroki Miyahara
- Department of NeuroHealth Innovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
| | - Jian Dai
- Department of NeuroHealth Innovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
| | - Xiaoran Cui
- Department of Aging Biology, Shinshu University Graduate School of Medicine, Science and Technology, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
| | - Ying Li
- Department of Aging Biology, Shinshu University Graduate School of Medicine, Science and Technology, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
| | - Xiaojing Kang
- Department of Aging Biology, Shinshu University Graduate School of Medicine, Science and Technology, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
| | - Keiichi Higuchi
- Department of Aging Biology, Shinshu University Graduate School of Medicine, Science and Technology, 3-1-1 Asahi, Matsumoto, 390-8621, Japan; Department of NeuroHealth Innovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
| | - Masayuki Mori
- Department of Aging Biology, Shinshu University Graduate School of Medicine, Science and Technology, 3-1-1 Asahi, Matsumoto, 390-8621, Japan; Department of NeuroHealth Innovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
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7
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Ghaddar N, Wang S, Woodvine B, Krishnamoorthy J, van Hoef V, Darini C, Kazimierczak U, Ah-Son N, Popper H, Johnson M, Officer L, Teodósio A, Broggini M, Mann KK, Hatzoglou M, Topisirovic I, Larsson O, Le Quesne J, Koromilas AE. The integrated stress response is tumorigenic and constitutes a therapeutic liability in KRAS-driven lung cancer. Nat Commun 2021; 12:4651. [PMID: 34330898 PMCID: PMC8324901 DOI: 10.1038/s41467-021-24661-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 06/30/2021] [Indexed: 12/11/2022] Open
Abstract
The integrated stress response (ISR) is an essential stress-support pathway increasingly recognized as a determinant of tumorigenesis. Here we demonstrate that ISR is pivotal in lung adenocarcinoma (LUAD) development, the most common histological type of lung cancer and a leading cause of cancer death worldwide. Increased phosphorylation of the translation initiation factor eIF2 (p-eIF2α), the focal point of ISR, is related to invasiveness, increased growth, and poor outcome in 928 LUAD patients. Dissection of ISR mechanisms in KRAS-driven lung tumorigenesis in mice demonstrated that p-eIF2α causes the translational repression of dual specificity phosphatase 6 (DUSP6), resulting in increased phosphorylation of the extracellular signal-regulated kinase (p-ERK). Treatments with ISR inhibitors, including a memory-enhancing drug with limited toxicity, provides a suitable therapeutic option for KRAS-driven lung cancer insofar as they substantially reduce tumor growth and prolong mouse survival. Our data provide a rationale for the implementation of ISR-based regimens in LUAD treatment.
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Affiliation(s)
- Nour Ghaddar
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada
- Division of Experimental Medicine, Department of Medicine, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Shuo Wang
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada
| | - Bethany Woodvine
- Leicester Cancer Research Centre, University of Leicester, Leicester, UK
- MRC Toxicology Unit, University of Cambridge, Leicester, UK
| | - Jothilatha Krishnamoorthy
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada
| | - Vincent van Hoef
- Department of Oncology-Pathology, Science for Life Laboratory, Karolinska Institute, Solna, Sweden
| | - Cedric Darini
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada
| | - Urszula Kazimierczak
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada
- Department of Cancer Immunology, Chair of Medical Biotechnology, Poznan University of Medical Sciences, Poznan, Poland
| | - Nicolas Ah-Son
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada
| | - Helmuth Popper
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Myriam Johnson
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada
- Division of Experimental Medicine, Department of Medicine, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Leah Officer
- MRC Toxicology Unit, University of Cambridge, Leicester, UK
| | - Ana Teodósio
- MRC Toxicology Unit, University of Cambridge, Leicester, UK
| | - Massimo Broggini
- Laboratory of Molecular Pharmacology IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri", Milan, Italy
| | - Koren K Mann
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada
- Gerald Bronfman Department of Oncology, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Maria Hatzoglou
- Department of Genetics, Case Western Reserve University, Cleveland, OH, USA
| | - Ivan Topisirovic
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada
- Gerald Bronfman Department of Oncology, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Ola Larsson
- Department of Oncology-Pathology, Science for Life Laboratory, Karolinska Institute, Solna, Sweden
| | - John Le Quesne
- Leicester Cancer Research Centre, University of Leicester, Leicester, UK.
- MRC Toxicology Unit, University of Cambridge, Leicester, UK.
- Beatson Cancer Research Institute, Glasgow, UK.
| | - Antonis E Koromilas
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, QC, Canada.
- Gerald Bronfman Department of Oncology, Faculty of Medicine, McGill University, Montreal, QC, Canada.
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Palukaitis P, Kim S. Resistance to Turnip Mosaic Virus in the Family Brassicaceae. THE PLANT PATHOLOGY JOURNAL 2021; 37:1-23. [PMID: 33551693 PMCID: PMC7847761 DOI: 10.5423/ppj.rw.09.2020.0178] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/30/2020] [Accepted: 11/30/2020] [Indexed: 05/21/2023]
Abstract
Resistance to diseases caused by turnip mosaic virus (TuMV) in crop species of the family Brassicaceae has been studied extensively, especially in members of the genus Brassica. The variation in response observed on resistant and susceptible plants inoculated with different isolates of TuMV is due to a combination of the variation in the plant resistome and the variation in the virus genome. Here, we review the breadth of this variation, both at the level of variation in TuMV sequences, with one eye towards the phylogeny and evolution of the virus, and another eye towards the nature of the various responses observed in susceptible vs. different types of resistance responses. The analyses of the viral genomes allowed comparisons of pathotyped viruses on particular indicator hosts to produce clusters of host types, while the inclusion of phylogeny data and geographic location allowed the formation of the host/geographic cluster groups, the derivation of both of which are presented here. Various studies on resistance determination in particular brassica crops sometimes led to further genetic studies, in many cases to include the mapping of genes, and in some cases to the actual identification of the genes. In addition to summarizing the results from such studies done in brassica crops, as well as in radish and Arabidopsis (the latter as a potential source of candidate genes for brassica and radish), we also summarize work done using nonconventional approaches to obtaining resistance to TuMV.
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Affiliation(s)
- Peter Palukaitis
- Department of Horticultural Sciences, Seoul Women’s University, Seoul 0797, Korea
- Co-corresponding authors P. Palukaitis, Phone) +82-2-970-5614, FAX) +82-2-970-5610, E-mail) , S. Kim, Phone) +82-31-5182-8112, FAX) +82-31-5182-8113, E-mail) , ORCID, Peter Palukaitis https://orcid.org/0000-0001-8735-1273
| | - Su Kim
- Institute of Plant Analysis Technology Development, The Saeron Co., Suwon 16648, Korea
- Co-corresponding authors P. Palukaitis, Phone) +82-2-970-5614, FAX) +82-2-970-5610, E-mail) , S. Kim, Phone) +82-31-5182-8112, FAX) +82-31-5182-8113, E-mail) , ORCID, Peter Palukaitis https://orcid.org/0000-0001-8735-1273
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Khan MF, Spurgeon SK, Yan XG, Nofal MM, Al-Hmouz R. Inbuilt Tendency of the eIF2 Regulatory System to Counteract Uncertainties. IEEE Trans Nanobioscience 2020; 20:35-41. [PMID: 32894719 DOI: 10.1109/tnb.2020.3022415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Eukaryotic initiation factor 2 (eIF2) plays a fundamental role in the regulation of protein synthesis. Investigations have revealed that the regulation of eIF2 is robust against intrinsic uncertainties and is able to efficiently counteract them. The robustness properties of the eIF2 pathway against intrinsic disturbances is also well known. However the reasons for this ability to counteract stresses is less well understood. In this article, the robustness conferring properties of the eIF2 dependent regulatory system is explored with the help of a mathematical model. The novelty of the work presented in this article lies in articulating the possible reason behind the inbuilt robustness of the highly engineered eIF2 system against intrinsic perturbations. Our investigations reveal that the robust nature of the eIF2 pathway may originate from the existence of an attractive natural sliding surface within the system satisfying reaching and sliding conditions that are well established in the domain of control engineering.
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10
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Keefe MD, Soderholm HE, Shih HY, Stevenson TJ, Glaittli KA, Bowles DM, Scholl E, Colby S, Merchant S, Hsu EW, Bonkowsky JL. Vanishing white matter disease expression of truncated EIF2B5 activates induced stress response. eLife 2020; 9:56319. [PMID: 33300869 PMCID: PMC7752137 DOI: 10.7554/elife.56319] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 12/09/2020] [Indexed: 02/07/2023] Open
Abstract
Vanishing white matter disease (VWM) is a severe leukodystrophy of the central nervous system caused by mutations in subunits of the eukaryotic initiation factor 2B complex (eIF2B). Current models only partially recapitulate key disease features, and pathophysiology is poorly understood. Through development and validation of zebrafish (Danio rerio) models of VWM, we demonstrate that zebrafish eif2b mutants phenocopy VWM, including impaired somatic growth, early lethality, effects on myelination, loss of oligodendrocyte precursor cells, increased apoptosis in the CNS, and impaired motor swimming behavior. Expression of human EIF2B2 in the zebrafish eif2b2 mutant rescues lethality and CNS apoptosis, demonstrating conservation of function between zebrafish and human. In the mutants, intron 12 retention leads to expression of a truncated eif2b5 transcript. Expression of the truncated eif2b5 in wild-type larva impairs motor behavior and activates the ISR, suggesting that a feed-forward mechanism in VWM is a significant component of disease pathophysiology.
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Affiliation(s)
- Matthew D Keefe
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, United States
| | - Haille E Soderholm
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, United States
| | - Hung-Yu Shih
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, United States
| | - Tamara J Stevenson
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, United States
| | - Kathryn A Glaittli
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, United States
| | - D Miranda Bowles
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, United States
| | - Erika Scholl
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, United States
| | - Samuel Colby
- Department of Bioengineering, University of Utah, Salt Lake City, United States
| | - Samer Merchant
- Department of Bioengineering, University of Utah, Salt Lake City, United States
| | - Edward W Hsu
- Department of Bioengineering, University of Utah, Salt Lake City, United States
| | - Joshua L Bonkowsky
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, United States.,Brain and Spine Center, Primary Children's Hospital, Salt Lake City, United States
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Skariah G, Todd PK. Translational control in aging and neurodegeneration. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 12:e1628. [PMID: 32954679 DOI: 10.1002/wrna.1628] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 08/19/2020] [Accepted: 09/07/2020] [Indexed: 12/13/2022]
Abstract
Protein metabolism plays central roles in age-related decline and neurodegeneration. While a large body of research has explored age-related changes in protein degradation, alterations in the efficiency and fidelity of protein synthesis with aging are less well understood. Age-associated changes occur in both the protein synthetic machinery (ribosomal proteins and rRNA) and within regulatory factors controlling translation. At the same time, many of the interventions that prolong lifespan do so in part by pre-emptively decreasing protein synthesis rates to allow better harmonization to age-related declines in protein catabolism. Here we review the roles of translation regulation in aging, with a specific focus on factors implicated in age-related neurodegeneration. We discuss how emerging technologies such as ribosome profiling and superior mass spectrometric approaches are illuminating age-dependent mRNA-specific changes in translation rates across tissues to reveal a critical interplay between catabolic and anabolic pathways that likely contribute to functional decline. These new findings point to nodes in posttranscriptional gene regulation that both contribute to aging and offer targets for therapy. This article is categorized under: Translation > Translation Regulation Translation > Ribosome Biogenesis Translation > Translation Mechanisms.
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Affiliation(s)
- Geena Skariah
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Peter K Todd
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
- Ann Arbor VA Healthcare System, Department of Veterans Affairs, Ann Arbor, Michigan, USA
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12
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Malvezzi AM, Aricó M, Souza-Melo N, Dos Santos GP, Bittencourt-Cunha P, Holetz FB, Schenkman S. GCN2-Like Kinase Modulates Stress Granule Formation During Nutritional Stress in Trypanosoma cruzi. Front Cell Infect Microbiol 2020; 10:149. [PMID: 32373547 PMCID: PMC7176912 DOI: 10.3389/fcimb.2020.00149] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 03/20/2020] [Indexed: 12/24/2022] Open
Abstract
The integrated stress response in eukaryotic cells is an orchestrated pathway that leads to eukaryotic Initiation Factor 2 alpha subunit (eIF2α) phosphorylation at ser51 and ultimately activates pathways to mitigate cellular damages. Three putative kinases (Tck1, Tck2, and Tck3) are found in the Trypanosoma cruzi genome, the flagellated parasite that causes Chagas disease. These kinases present similarities to other eukaryotic eIF2α kinases, exhibiting a typical insertion loop in the kinase domain of the protein. We found that this insertion loop is conserved among kinase 1 of several T. cruzi strains but differs among various Kinetoplastidae species, suggesting unique roles. Kinase 1 is orthologous of GCN2 of several eukaryotes, which have been implicated in the eIF2α ser51 phosphorylation in situations that mainly affects the nutrients levels. Therefore, we further investigated the responses to nutritional stress of T. cruzi devoid of TcK1 generated by CRISPR/Cas9 gene replacement. In nutrient-rich conditions, replicative T. cruzi epimastigotes depleted of TcK1 proliferate as wild type cells but showed increased levels of polysomes relative to monosomes. Upon nutritional deprivation, the polysomes decreased more than in TcK1 depleted line. However, eIF2α is still phosphorylated in TcK1 depleted line, as in wild type parasites. eIF2α phosphorylation increased at longer incubations times, but KO parasites showed less accumulation of ribonucleoprotein granules containing ATP-dependent RNA helicase involved in mRNA turnover (DHH1) and Poly-A binding protein (PABP1). Additionally, the formation of metacyclic-trypomastigotes is increased in the absence of Tck1 compared to controls. These metacyclics, as well as tissue culture trypomastigotes derived from the TcK1 knockout line, were less infective to mammalian host cells, although replicated faster inside mammalian cells. These results indicate that GCN2-like kinase in T. cruzi affects stress granule formation, independently of eIF2α phosphorylation upon nutrient deprivation. It also modulates the fate of the parasites during differentiation, invasion, and intracellular proliferation.
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Affiliation(s)
- Amaranta Muniz Malvezzi
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Mirella Aricó
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Normanda Souza-Melo
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Gregory Pedroso Dos Santos
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Paula Bittencourt-Cunha
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | - Sergio Schenkman
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
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13
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Marini G, Nüske E, Leng W, Alberti S, Pigino G. Reorganization of budding yeast cytoplasm upon energy depletion. Mol Biol Cell 2020; 31:1232-1245. [PMID: 32293990 PMCID: PMC7353153 DOI: 10.1091/mbc.e20-02-0125] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Yeast cells, when exposed to stress, can enter a protective state in which cell division, growth, and metabolism are down-regulated. They remain viable in this state until nutrients become available again. How cells enter this protective survival state and what happens at a cellular and subcellular level are largely unknown. In this study, we used electron tomography to investigate stress-induced ultrastructural changes in the cytoplasm of yeast cells. After ATP depletion, we observed significant cytosolic compaction and extensive cytoplasmic reorganization, as well as the emergence of distinct membrane-bound and membraneless organelles. Using correlative light and electron microscopy, we further demonstrated that one of these membraneless organelles was generated by the reversible polymerization of eukaryotic translation initiation factor 2B, an essential enzyme in the initiation of protein synthesis, into large bundles of filaments. The changes we observe are part of a stress-induced survival strategy, allowing yeast cells to save energy, protect proteins from degradation, and inhibit protein functionality by forming assemblies of proteins.
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Affiliation(s)
- Guendalina Marini
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Elisabeth Nüske
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Weihua Leng
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Gaia Pigino
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
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14
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Link AJ, Niu X, Weaver CM, Jennings JL, Duncan DT, McAfee KJ, Sammons M, Gerbasi VR, Farley AR, Fleischer TC, Browne CM, Samir P, Galassie A, Boone B. Targeted Identification of Protein Interactions in Eukaryotic mRNA Translation. Proteomics 2020; 20:e1900177. [PMID: 32027465 DOI: 10.1002/pmic.201900177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 12/13/2019] [Indexed: 11/09/2022]
Abstract
To identify protein-protein interactions and phosphorylated amino acid sites in eukaryotic mRNA translation, replicate TAP-MudPIT and control experiments are performed targeting Saccharomyces cerevisiae genes previously implicated in eukaryotic mRNA translation by their genetic and/or functional roles in translation initiation, elongation, termination, or interactions with ribosomal complexes. Replicate tandem affinity purifications of each targeted yeast TAP-tagged mRNA translation protein coupled with multidimensional liquid chromatography and tandem mass spectrometry analysis are used to identify and quantify copurifying proteins. To improve sensitivity and minimize spurious, nonspecific interactions, a novel cross-validation approach is employed to identify the most statistically significant protein-protein interactions. Using experimental and computational strategies discussed herein, the previously described protein composition of the canonical eukaryotic mRNA translation initiation, elongation, and termination complexes is calculated. In addition, statistically significant unpublished protein interactions and phosphorylation sites for S. cerevisiae's mRNA translation proteins and complexes are identified.
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Affiliation(s)
- Andrew J Link
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA.,Department of Biochemistry, Vanderbilt University, Nashville, TN, 37232, USA.,Department of Chemistry, Vanderbilt University, Nashville, TN, 37232, USA
| | - Xinnan Niu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Connie M Weaver
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Jennifer L Jennings
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Dexter T Duncan
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - K Jill McAfee
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Morgan Sammons
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37232, USA
| | - Vince R Gerbasi
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Adam R Farley
- Department of Biochemistry, Vanderbilt University, Nashville, TN, 37232, USA
| | - Tracey C Fleischer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | | | - Parimal Samir
- Department of Biochemistry, Vanderbilt University, Nashville, TN, 37232, USA
| | - Allison Galassie
- Department of Chemistry, Vanderbilt University, Nashville, TN, 37232, USA
| | - Braden Boone
- Department of Bioinformatics, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
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15
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De Franco E, Caswell R, Johnson MB, Wakeling MN, Zung A, Dũng VC, Bích Ngọc CT, Goonetilleke R, Vivanco Jury M, El-Khateeb M, Ellard S, Flanagan SE, Ron D, Hattersley AT. De Novo Mutations in EIF2B1 Affecting eIF2 Signaling Cause Neonatal/Early-Onset Diabetes and Transient Hepatic Dysfunction. Diabetes 2020; 69:477-483. [PMID: 31882561 PMCID: PMC7100014 DOI: 10.2337/db19-1029] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 12/18/2019] [Indexed: 12/21/2022]
Abstract
Permanent neonatal diabetes mellitus (PNDM) is caused by reduced β-cell number or impaired β-cell function. Understanding of the genetic basis of this disorder highlights fundamental β-cell mechanisms. We performed trio genome sequencing for 44 patients with PNDM and their unaffected parents to identify causative de novo variants. Replication studies were performed in 188 patients diagnosed with diabetes before 2 years of age without a genetic diagnosis. EIF2B1 (encoding the eIF2B complex α subunit) was the only gene with novel de novo variants (all missense) in at least three patients. Replication studies identified two further patients with de novo EIF2B1 variants. In addition to having diabetes, four of five patients had hepatitis-like episodes in childhood. The EIF2B1 de novo mutations were found to map to the same protein surface. We propose that these variants render the eIF2B complex insensitive to eIF2 phosphorylation, which occurs under stress conditions and triggers expression of stress response genes. Failure of eIF2B to sense eIF2 phosphorylation likely leads to unregulated unfolded protein response and cell death. Our results establish de novo EIF2B1 mutations as a novel cause of permanent diabetes and liver dysfunction. These findings confirm the importance of cell stress regulation for β-cells and highlight EIF2B1's fundamental role within this pathway.
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Affiliation(s)
- Elisa De Franco
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, U.K.
| | - Richard Caswell
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, U.K
| | - Matthew B Johnson
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, U.K
| | - Matthew N Wakeling
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, U.K
| | - Amnon Zung
- Pediatric Endocrinology Unit, Kaplan Medical Center, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Vũ Chí Dũng
- Vietnam National Children's Hospital, Hanoi, Vietnam
| | | | | | | | | | - Sian Ellard
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, U.K
| | - Sarah E Flanagan
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, U.K
| | - David Ron
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, U.K
| | - Andrew T Hattersley
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, U.K
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16
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Anti-proliferative bioactivity against HT-29 colon cancer cells of a withanolides-rich extract from golden berry (Physalis peruviana L.) calyx investigated by Foodomics. J Funct Foods 2019. [DOI: 10.1016/j.jff.2019.103567] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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17
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Schmidt S, Gay D, Uthe FW, Denk S, Paauwe M, Matthes N, Diefenbacher ME, Bryson S, Warrander FC, Erhard F, Ade CP, Baluapuri A, Walz S, Jackstadt R, Ford C, Vlachogiannis G, Valeri N, Otto C, Schülein-Völk C, Maurus K, Schmitz W, Knight JRP, Wolf E, Strathdee D, Schulze A, Germer CT, Rosenwald A, Sansom OJ, Eilers M, Wiegering A. A MYC-GCN2-eIF2α negative feedback loop limits protein synthesis to prevent MYC-dependent apoptosis in colorectal cancer. Nat Cell Biol 2019; 21:1413-1424. [PMID: 31685988 PMCID: PMC6927814 DOI: 10.1038/s41556-019-0408-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 09/20/2019] [Indexed: 12/12/2022]
Abstract
Tumours depend on altered rates of protein synthesis for growth and survival, which suggests that mechanisms controlling mRNA translation may be exploitable for therapy. Here, we show that loss of APC, which occurs almost universally in colorectal tumours, strongly enhances the dependence on the translation initiation factor eIF2B5. Depletion of eIF2B5 induces an integrated stress response and enhances translation of MYC via an internal ribosomal entry site. This perturbs cellular amino acid and nucleotide pools, strains energy resources and causes MYC-dependent apoptosis. eIF2B5 limits MYC expression and prevents apoptosis in APC-deficient murine and patient-derived organoids and in APC-deficient murine intestinal epithelia in vivo. Conversely, the high MYC levels present in APC-deficient cells induce phosphorylation of eIF2α via the kinases GCN2 and PKR. Pharmacological inhibition of GCN2 phenocopies eIF2B5 depletion and has therapeutic efficacy in tumour organoids, which demonstrates that a negative MYC-eIF2α feedback loop constitutes a targetable vulnerability of colorectal tumours.
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Affiliation(s)
- Stefanie Schmidt
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | | | - Friedrich Wilhelm Uthe
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | - Sarah Denk
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | | | - Niels Matthes
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | | | | | | | - Florian Erhard
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Carsten Patrick Ade
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | - Apoorva Baluapuri
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | - Susanne Walz
- Comprehensive Cancer Center Mainfranken, Core Unit Bioinformatics, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | | | | | | | - Nicola Valeri
- Division of Molecular Pathology, The Institute of Cancer Research, London, UK
- Department of Medicine, The Royal Marsden NHS Trust, London, UK
| | - Christoph Otto
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | | | - Katja Maurus
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | - Werner Schmitz
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | | | - Elmar Wolf
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | | | - Almut Schulze
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | - Christoph-Thomas Germer
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | - Andreas Rosenwald
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | - Owen James Sansom
- CRUK Beatson Institute, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Martin Eilers
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany.
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany.
| | - Armin Wiegering
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany.
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany.
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany.
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18
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Janapala Y, Preiss T, Shirokikh NE. Control of Translation at the Initiation Phase During Glucose Starvation in Yeast. Int J Mol Sci 2019; 20:E4043. [PMID: 31430885 PMCID: PMC6720308 DOI: 10.3390/ijms20164043] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/10/2019] [Accepted: 08/15/2019] [Indexed: 12/13/2022] Open
Abstract
Glucose is one of the most important sources of carbon across all life. Glucose starvation is a key stress relevant to all eukaryotic cells. Glucose starvation responses have important implications in diseases, such as diabetes and cancer. In yeast, glucose starvation causes rapid and dramatic effects on the synthesis of proteins (mRNA translation). Response to glucose deficiency targets the initiation phase of translation by different mechanisms and with diverse dynamics. Concomitantly, translationally repressed mRNAs and components of the protein synthesis machinery may enter a variety of cytoplasmic foci, which also form with variable kinetics and may store or degrade mRNA. Much progress has been made in understanding these processes in the last decade, including with the use of high-throughput/omics methods of RNA and RNA:protein detection. This review dissects the current knowledge of yeast reactions to glucose starvation systematized by the stage of translation initiation, with the focus on rapid responses. We provide parallels to mechanisms found in higher eukaryotes, such as metazoans, for the most critical responses, and point out major remaining gaps in knowledge and possible future directions of research on translational responses to glucose starvation.
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Affiliation(s)
- Yoshika Janapala
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
| | - Thomas Preiss
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia.
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.
| | - Nikolay E Shirokikh
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia.
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19
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Circadian Proteomic Analysis Uncovers Mechanisms of Post-Transcriptional Regulation in Metabolic Pathways. Cell Syst 2018; 7:613-626.e5. [PMID: 30553726 DOI: 10.1016/j.cels.2018.10.014] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 08/12/2018] [Accepted: 10/29/2018] [Indexed: 12/20/2022]
Abstract
Transcriptional and translational feedback loops in fungi and animals drive circadian rhythms in transcript levels that provide output from the clock, but post-transcriptional mechanisms also contribute. To determine the extent and underlying source of this regulation, we applied newly developed analytical tools to a long-duration, deeply sampled, circadian proteomics time course comprising half of the proteome. We found a quarter of expressed proteins are clock regulated, but >40% of these do not arise from clock-regulated transcripts, and our analysis predicts that these protein rhythms arise from oscillations in translational rates. Our data highlighted the impact of the clock on metabolic regulation, with central carbon metabolism reflecting both transcriptional and post-transcriptional control and opposing metabolic pathways showing peak activities at different times of day. The transcription factor CSP-1 plays a role in this metabolic regulation, contributing to the rhythmicity and phase of clock-regulated proteins.
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20
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Major structural rearrangements of the canonical eukaryotic translation initiation complex. Curr Opin Struct Biol 2018; 53:151-158. [DOI: 10.1016/j.sbi.2018.08.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 08/28/2018] [Indexed: 12/24/2022]
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21
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Khan MF, Spurgeon SK, Yan XG. Modeling and Dynamic Behavior of eIF2 Dependent Regulatory System With Disturbances. IEEE Trans Nanobioscience 2018; 17:518-524. [PMID: 30281470 DOI: 10.1109/tnb.2018.2873027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Eukaryotic initiation factor 2 (eIF2) is a central controller of the eukaryotic translational machinery. To sustain the on-going translation activity, eIF2 cycles between its GTP and GDP bound states. However, in response to cellular stresses, the phosphorylation of eIF2 takes place, which acts as an inhibitor of the guanine nucleotide exchange factor eIF2B and switches the translation activity on physiological timescales. The main objective of this paper is to investigate the stability of the regulatory system under nominal conditions, parametric fluctuations, and structural damages. In this paper, a mathematical model of eIF2-dependent regulatory system is used to identify the stability-conferring features within the system with the help of direct and indirect methods of Lyapunov stability theory. To investigate the impact of intrinsic fluctuations and structural damages on the stability of regulatory system, the mathematical model has been linearized around feasible equilibrium point and the variation of system poles has been observed. The investigations have revealed that the regulatory model is stable and able to tolerate the intrinsic stressors but becomes unstable when particular complex is targeted to override the undesirable interaction. Our analyses indicate that, the stability is a collective property and damage in the structure of the system changes the stability of the system.
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22
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Mervosh NL, Wilson R, Rauniyar N, Hofford RS, Kutlu MG, Calipari ES, Lam TT, Kiraly DD. Granulocyte-Colony-Stimulating Factor Alters the Proteomic Landscape of the Ventral Tegmental Area. Proteomes 2018; 6:proteomes6040035. [PMID: 30249060 PMCID: PMC6313867 DOI: 10.3390/proteomes6040035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 09/17/2018] [Accepted: 09/20/2018] [Indexed: 12/12/2022] Open
Abstract
Cocaine addiction is characterized by aberrant plasticity of the mesolimbic dopamine circuit, leading to dysregulation of motivation to seek and take drug. Despite the significant toll that cocaine use disorder exacts on society, there are currently no available pharmacotherapies. We have recently identified granulocyte-colony stimulating factor (G-CSF) as a soluble cytokine that alters the behavioral response to cocaine and which increases dopamine release from the ventral tegmental area (VTA). Despite these known effects on behavior and neurophysiology, the molecular mechanisms by which G-CSF affects brain function are unclear. In this study mice were treated with repeated injections of G-CSF, cocaine or a combination and changes in protein expression in the VTA were examined using an unbiased proteomics approach. Repeated G-CSF treatment resulted in alterations in multiple signaling pathways related to synaptic plasticity and neuronal morphology. While the treatment groups had marked overlap in their effect, injections of cocaine and the combination of cocaine and G-CSF lead to distinct patterns of significantly regulated proteins. These experiments provide valuable information as to the molecular pathways that G-CSF activates in an important limbic brain region and will help to guide further characterization of G-CSF function and evaluation as a possible translational target.
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Affiliation(s)
- Nicholas L Mervosh
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
- Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| | - Rashaun Wilson
- Yale/NIDA Neuroproteomics Center, New Haven, CT 06511, USA.
| | - Navin Rauniyar
- Yale/NIDA Neuroproteomics Center, New Haven, CT 06511, USA.
| | - Rebecca S Hofford
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
- Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| | - Munir Gunes Kutlu
- Department of Pharmacology, Vanderbilt Center for Addiction Research, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Erin S Calipari
- Department of Pharmacology, Vanderbilt Center for Addiction Research, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - TuKiet T Lam
- Yale/NIDA Neuroproteomics Center, New Haven, CT 06511, USA.
- Department of Molecular Biophysics & Biochemistry, New Haven, CT 06510, USA.
- Yale MS & Proteomics Resource, New Haven, CT 06510, USA.
| | - Drew D Kiraly
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
- Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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23
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Pavitt GD. Regulation of translation initiation factor eIF2B at the hub of the integrated stress response. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 9:e1491. [PMID: 29989343 DOI: 10.1002/wrna.1491] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/08/2018] [Accepted: 05/22/2018] [Indexed: 12/29/2022]
Abstract
Phosphorylation of the translation initiation factor eIF2 is one of the most widely used and well-studied mechanisms cells use to respond to diverse cellular stresses. Known as the integrated stress response (ISR), the control pathway uses modulation of protein synthesis to reprogram gene expression and restore homeostasis. Here the current knowledge of the molecular mechanisms of eIF2 activation and its control by phosphorylation at a single-conserved phosphorylation site, serine 51 are discussed with a major focus on the regulatory roles of eIF2B and eIF5 where a current molecular view of ISR control of eIF2B activity is presented. How genetic disorders affect eIF2 or eIF2B is discussed, as are syndromes where excess signaling through the ISR is a component. Finally, studies into the action of recently identified compounds that modulate the ISR in experimental systems are discussed; these suggest that eIF2B is a potential therapeutic target for a wide range of conditions. This article is categorized under: Translation > Translation Regulation.
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Affiliation(s)
- Graham D Pavitt
- Division Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
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Chu J, Pelletier J. Therapeutic Opportunities in Eukaryotic Translation. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a032995. [PMID: 29440069 DOI: 10.1101/cshperspect.a032995] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The ability to block biological processes with selective small molecules provides advantages distinct from most other experimental approaches. These include rapid time to onset, swift reversibility, ability to probe activities in manners that cannot be accessed by genetic means, and the potential to be further developed as therapeutic agents. Small molecule inhibitors can also be used to alter expression and activity without affecting the stoichiometry of interacting partners. These tenets have been especially evident in the field of translation. Small molecule inhibitors were instrumental in enabling investigators to capture short-lived complexes and characterize specific steps of protein synthesis. In addition, several drugs that are the mainstay of modern antimicrobial drug therapy are potent inhibitors of prokaryotic translation. Currently, there is much interest in targeting eukaryotic translation as decades of research have revealed that deregulated protein synthesis in cancer cells represents a targetable vulnerability. In addition to being potential therapeutics, small molecules that manipulate translation have also been shown to influence cognitive processes such as memory. In this review, we focus on small molecule modulators that target the eukaryotic translation initiation apparatus and provide an update on their potential application to the treatment of disease.
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Affiliation(s)
- Jennifer Chu
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada.,Department of Oncology, McGill University, Montreal, Quebec H3G 1Y6, Canada.,Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3G 1Y6, Canada
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25
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Shirokikh NE, Preiss T. Translation initiation by cap-dependent ribosome recruitment: Recent insights and open questions. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 9:e1473. [PMID: 29624880 DOI: 10.1002/wrna.1473] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 02/02/2018] [Accepted: 02/14/2018] [Indexed: 12/14/2022]
Abstract
Gene expression universally relies on protein synthesis, where ribosomes recognize and decode the messenger RNA template by cycling through translation initiation, elongation, and termination phases. All aspects of translation have been studied for decades using the tools of biochemistry and molecular biology available at the time. Here, we focus on the mechanism of translation initiation in eukaryotes, which is remarkably more complex than prokaryotic initiation and is the target of multiple types of regulatory intervention. The "consensus" model, featuring cap-dependent ribosome entry and scanning of mRNA leader sequences, represents the predominantly utilized initiation pathway across eukaryotes, although several variations of the model and alternative initiation mechanisms are also known. Recent advances in structural biology techniques have enabled remarkable molecular-level insights into the functional states of eukaryotic ribosomes, including a range of ribosomal complexes with different combinations of translation initiation factors that are thought to represent bona fide intermediates of the initiation process. Similarly, high-throughput sequencing-based ribosome profiling or "footprinting" approaches have allowed much progress in understanding the elongation phase of translation, and variants of them are beginning to reveal the remaining mysteries of initiation, as well as aspects of translation termination and ribosomal recycling. A current view on the eukaryotic initiation mechanism is presented here with an emphasis on how recent structural and footprinting results underpin axioms of the consensus model. Along the way, we further outline some contested mechanistic issues and major open questions still to be addressed. This article is categorized under: Translation > Translation Mechanisms Translation > Translation Regulation RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.
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Affiliation(s)
- Nikolay E Shirokikh
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
- Victor Chang Cardiac Research Institute, Darlinghurst, Australia
| | - Thomas Preiss
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
- Victor Chang Cardiac Research Institute, Darlinghurst, Australia
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Mao X, Ren M, Chen D, Yu B, Che L, He J, Luo J, Luo Y, Wang J, Sun H. Leucine modulates the IPEC-J2 cell proteome associated with cell proliferation, metabolism and phagocytosis. ACTA ACUST UNITED AC 2018; 4:316-321. [PMID: 30175261 PMCID: PMC6116325 DOI: 10.1016/j.aninu.2018.03.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/14/2018] [Accepted: 03/19/2018] [Indexed: 12/21/2022]
Abstract
Leucine can affect intestinal protein expressions, and improve mucosal immune function. However, little study has been conducted to determine the change of protein component by leucine treatment in intestine epithelial cells. The present study was to cover the key proteins and cell pathways that could be regulated by leucine treatment in porcine intestinal epithelial cell line (IPEC-J2) cells with the approach of proteome analysis. A total number of 3,211 proteins were identified in our approach by searching the database of Uniprot sus scrofa. Among identified proteins, there were 101 proteins expressed differently between control group and leucine group. Compared with the control group, there were 50 up-regulated proteins and 51 down-regulated proteins in leucine group. In these proteins, leucine treatment decreased the expression of some proteins including pyruvate kinase, glyceraldehyde-3-phosphate dehydrogenase, E3 ubiquitin ligase, cathepsin D, caspase 3 and caspase 6, and increased the levels of some proteins, such as some eukaryotic translation initiation factors, ubiquitin carboxyl-terminal hydrolase, DNA-related RNA polymerase II, urokinase plasminogen activator, cyclin-dependent kinase inhibitor 2b, MutL homolog 1, 5-methylcytosine binding domain 4, polymerase δ, α-tubulin, syntaxin 18, Ras homolog D, actin related protein 2/3 complex and cofilin. Via the analysis of Gene Ontology and pathways, these proteins in IPEC-J2 cells were related with some physiological functions, such as protein metabolism, glycolysis, cell proliferation, apoptosis and phagocytosis. Thus, these results suggest that leucine affects gut barrier function possibly via regulating cell proliferation and apoptosis, metabolism and phagocytosis.
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Affiliation(s)
- Xiangbing Mao
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China
- Corresponding authors.
| | - Man Ren
- Animal Science Collage, Anhui Science and Technology University, Chuzhou 233100, China
| | - Daiwen Chen
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China
| | - Bing Yu
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China
| | - Lianqiang Che
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China
- Corresponding authors.
| | - Jun He
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China
| | - Junqiu Luo
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China
| | - Yuheng Luo
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China
| | - Jianping Wang
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China
| | - Hui Sun
- College of Animal Science and Technology, Jilin Agricultural University, Changchun 130033, China
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27
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Gunišová S, Hronová V, Mohammad MP, Hinnebusch AG, Valášek LS. Please do not recycle! Translation reinitiation in microbes and higher eukaryotes. FEMS Microbiol Rev 2018; 42:165-192. [PMID: 29281028 PMCID: PMC5972666 DOI: 10.1093/femsre/fux059] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 12/20/2017] [Indexed: 12/14/2022] Open
Abstract
Protein production must be strictly controlled at its beginning and end to synthesize a polypeptide that faithfully copies genetic information carried in the encoding mRNA. In contrast to viruses and prokaryotes, the majority of mRNAs in eukaryotes contain only one coding sequence, resulting in production of a single protein. There are, however, many exceptional mRNAs that either carry short open reading frames upstream of the main coding sequence (uORFs) or even contain multiple long ORFs. A wide variety of mechanisms have evolved in microbes and higher eukaryotes to prevent recycling of some or all translational components upon termination of the first translated ORF in such mRNAs and thereby enable subsequent translation of the next uORF or downstream coding sequence. These specialized reinitiation mechanisms are often regulated to couple translation of the downstream ORF to various stimuli. Here we review all known instances of both short uORF-mediated and long ORF-mediated reinitiation and present our current understanding of the underlying molecular mechanisms of these intriguing modes of translational control.
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Affiliation(s)
- Stanislava Gunišová
- Laboratory of Regulation of Gene Expression, Institute of Microbiology ASCR, Videnska 1083, Prague, 142 20, the Czech Republic
| | - Vladislava Hronová
- Laboratory of Regulation of Gene Expression, Institute of Microbiology ASCR, Videnska 1083, Prague, 142 20, the Czech Republic
| | - Mahabub Pasha Mohammad
- Laboratory of Regulation of Gene Expression, Institute of Microbiology ASCR, Videnska 1083, Prague, 142 20, the Czech Republic
| | - Alan G Hinnebusch
- Laboratory of Gene Regulation and Development, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892, USA
| | - Leoš Shivaya Valášek
- Laboratory of Regulation of Gene Expression, Institute of Microbiology ASCR, Videnska 1083, Prague, 142 20, the Czech Republic
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Kugeratski FG, Batista M, Lima CVDP, Neilson LJ, da Cunha ES, de Godoy LM, Zanivan S, Krieger MA, Marchini FK. Mitogen-Activated Protein Kinase Kinase 5 Regulates Proliferation and Biosynthetic Processes in Procyclic Forms of Trypanosoma brucei. J Proteome Res 2018; 17:108-118. [PMID: 29043805 DOI: 10.1021/acs.jproteome.7b00415] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The pathogenic protozoan T. brucei alternates into distinct developmental stages in the mammalian and insect hosts. The mitogen-activated protein kinase (MAPK) signaling pathways transduce extracellular stimuli into a range of cellular responses, which ultimately lead to the adaptation to the external environment. Here, we combined a loss of function approach with stable isotope labeling with amino acids in cell culture (SILAC)-based mass spectrometry (MS) to investigate the role of the mitogen-activated protein kinase kinase 5 (MKK5) in T. brucei. The silencing of MKK5 significantly decreased the proliferation of procyclic forms of T. brucei. To shed light on the molecular alterations associated with this phenotype, we measured the total proteome and phosphoproteome of cells silenced for MKK5. In the total proteome, we observed a general decrease in proteins related to ribosome and translation as well as down-regulation of several components of the fatty acids biosynthesis pathway. In addition, we observed alterations in the protein levels and phosphorylation of key metabolic enzymes, which point toward a suppression of the oxidative metabolism. Taken together, our findings show that the silencing of MKK5 alters cell growth, energy metabolism, protein and fatty acids biosynthesis in procyclic T. brucei.
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Affiliation(s)
- Fernanda G Kugeratski
- CRUK Beatson Institute, Glasgow G61 1BD, U.K
- University of Glasgow, Glasgow G12 8QQ, U.K
| | | | | | | | | | | | - Sara Zanivan
- CRUK Beatson Institute, Glasgow G61 1BD, U.K
- University of Glasgow, Glasgow G12 8QQ, U.K
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Fernandes N, Eshleman N, Buchan JR. Stress Granules and ALS: A Case of Causation or Correlation? ADVANCES IN NEUROBIOLOGY 2018; 20:173-212. [PMID: 29916020 DOI: 10.1007/978-3-319-89689-2_7] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease characterized by cytoplasmic protein aggregates within motor neurons. These aggregates are linked to ALS pathogenesis. Recent evidence has suggested that stress granules may aid the formation of ALS protein aggregates. Here, we summarize current understanding of stress granules, focusing on assembly and clearance. We also assess the evidence linking alterations in stress granule formation and dynamics to ALS protein aggregates and disease pathology.
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Affiliation(s)
- Nikita Fernandes
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, USA
| | - Nichole Eshleman
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, USA
| | - J Ross Buchan
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, USA.
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30
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Kapur M, Monaghan CE, Ackerman SL. Regulation of mRNA Translation in Neurons-A Matter of Life and Death. Neuron 2017; 96:616-637. [PMID: 29096076 DOI: 10.1016/j.neuron.2017.09.057] [Citation(s) in RCA: 146] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 09/20/2017] [Accepted: 09/28/2017] [Indexed: 12/14/2022]
Abstract
Dynamic regulation of mRNA translation initiation and elongation is essential for the survival and function of neural cells. Global reductions in translation initiation resulting from mutations in the translational machinery or inappropriate activation of the integrated stress response may contribute to pathogenesis in a subset of neurodegenerative disorders. Aberrant proteins generated by non-canonical translation initiation may be a factor in the neuron death observed in the nucleotide repeat expansion diseases. Dysfunction of central components of the elongation machinery, such as the tRNAs and their associated enzymes, can cause translational infidelity and ribosome stalling, resulting in neurodegeneration. Taken together, dysregulation of mRNA translation is emerging as a unifying mechanism underlying the pathogenesis of many neurodegenerative disorders.
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Affiliation(s)
- Mridu Kapur
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Caitlin E Monaghan
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Susan L Ackerman
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA.
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31
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Shopan J, Mou H, Zhang L, Zhang C, Ma W, Walsh JA, Hu Z, Yang J, Zhang M. Eukaryotic translation initiation factor 2B-beta (eIF2Bβ), a new class of plant virus resistance gene. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 90:929-940. [PMID: 28244149 DOI: 10.1111/tpj.13519] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 02/14/2017] [Accepted: 02/15/2017] [Indexed: 05/12/2023]
Abstract
Recessive resistances to plant viruses in the Potyvirus genus have been found to be based on mutations in the plant eukaryotic translation initiation factors, eIF4E and eIF4G or their isoforms. Here we report that natural, monogenic recessive resistance to the Potyvirus Turnip mosaic virus (TuMV) has been found in a number of mustard (Brassica juncea) accessions. Bulked segregant analysis and sequencing of resistant and susceptible plant lines indicated the resistance is controlled by a single recessive gene, recessive TuMV resistance 03 (retr03), an allele of the eukaryotic translation initiation factor 2B-beta (eIF2Bβ). Silencing of eIF2Bβ in a TuMV-susceptible mustard plant line and expression of eIF2Bβ from a TuMV-susceptible line in a TuMV-resistant mustard plant line confirmed the new resistance mechanism. A functional copy of a specific allele of eIF2Bβ is required for efficient TuMV infection. eIF2Bβ represents a new class of virus resistance gene conferring resistance to any pathogen. eIF2B acts as a guanine nucleotide exchange factor (GEF) for its GTP-binding protein partner eIF2 via interaction with eIF2·GTP at an early step in translation initiation. Further genotyping indicated that a single non-synonymous substitution (A120G) in the N-terminal region of eIF2Bβ was responsible for the TuMV resistance. A reproducible marker has been developed, facilitating marker-assisted selection for TuMV resistance in B. juncea. Our findings provide a new target for seeking natural resistance to potyviruses and new opportunities for the control of potyviruses using genome editing techniques targeted on eIF2Bβ.
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Affiliation(s)
- Jannat Shopan
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China
| | - Haipeng Mou
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China
| | - Lili Zhang
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China
| | - Changtong Zhang
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China
| | - Weiwei Ma
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China
| | - John A Walsh
- School of Life Science, University of Warwick, Wellesbourne, Warwick, CV35 9EF, UK
| | - Zhongyuan Hu
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China
- Key laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Hangzhou, 310058, China
| | - Jinghua Yang
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China
- Key laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Hangzhou, 310058, China
| | - Mingfang Zhang
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China
- School of Life Science, University of Warwick, Wellesbourne, Warwick, CV35 9EF, UK
- Key laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, 310058, China
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Pettit AP, Jonsson WO, Bargoud AR, Mirek ET, Peelor FF, Wang Y, Gettys TW, Kimball SR, Miller BF, Hamilton KL, Wek RC, Anthony TG. Dietary Methionine Restriction Regulates Liver Protein Synthesis and Gene Expression Independently of Eukaryotic Initiation Factor 2 Phosphorylation in Mice. J Nutr 2017; 147:1031-1040. [PMID: 28446632 PMCID: PMC5443467 DOI: 10.3945/jn.116.246710] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/20/2017] [Accepted: 03/15/2017] [Indexed: 01/12/2023] Open
Abstract
Background: The phosphorylation of eukaryotic initiation factor 2 (p-eIF2) during dietary amino acid insufficiency reduces protein synthesis and alters gene expression via the integrated stress response (ISR).Objective: We explored whether a Met-restricted (MR) diet activates the ISR to reduce body fat and regulate protein balance.Methods: Male and female mice aged 3-6 mo with either whole-body deletion of general control nonderepressible 2 (Gcn2) or liver-specific deletion of protein kinase R-like endoplasmic reticulum kinase (Perk) alongside wild-type or floxed control mice were fed an obesogenic diet sufficient in Met (0.86%) or an MR (0.12% Met) diet for ≤5 wk. Ala enrichment with deuterium was measured to calculate protein synthesis rates. The guanine nucleotide exchange factor activity of eIF2B was measured alongside p-eIF2 and hepatic mRNA expression levels at 2 d and 5 wk. Metabolic phenotyping was conducted at 4 wk, and body composition was measured throughout. Results were evaluated with the use of ANOVA (P < 0.05).Results: Feeding an MR diet for 2 d did not increase hepatic p-eIF2 or reduce eIF2B activity in wild-type or Gcn2-/- mice, yet many genes transcriptionally regulated by the ISR were altered in both strains in the same direction and amplitude. Feeding an MR diet for 5 wk increased p-eIF2 and reduced eIF2B activity in wild-type but not Gcn2-/- mice, yet ISR-regulated genes altered in both strains similarly. Furthermore, the MR diet reduced mixed and cytosolic but not mitochondrial protein synthesis in both the liver and skeletal muscle regardless of Gcn2 status. Despite the similarities between strains, the MR diet did not increase energy expenditure or reduce body fat in Gcn2-/- mice. Finally, feeding the MR diet to mice with Perk deleted in the liver increased hepatic p-eIF2 and altered body composition similar to floxed controls.Conclusions: Hepatic activation of the ISR resulting from an MR diet does not require p-eIF2. Gcn2 status influences body fat loss but not protein balance when Met is restricted.
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Affiliation(s)
- Ashley P Pettit
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - William O Jonsson
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Albert R Bargoud
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Emily T Mirek
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Frederick F Peelor
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO
| | - Yongping Wang
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Thomas W Gettys
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Scot R Kimball
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey PA; and
| | - Benjamin F Miller
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO
| | - Karyn L Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO
| | - Ronald C Wek
- Department of Biochemistry of Molecular Biology, Indiana University School of Medicine, Indianapolis, IN
| | - Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ;
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33
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Mechanism and Regulation of Protein Synthesis in Saccharomyces cerevisiae. Genetics 2017; 203:65-107. [PMID: 27183566 DOI: 10.1534/genetics.115.186221] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 02/24/2016] [Indexed: 12/18/2022] Open
Abstract
In this review, we provide an overview of protein synthesis in the yeast Saccharomyces cerevisiae The mechanism of protein synthesis is well conserved between yeast and other eukaryotes, and molecular genetic studies in budding yeast have provided critical insights into the fundamental process of translation as well as its regulation. The review focuses on the initiation and elongation phases of protein synthesis with descriptions of the roles of translation initiation and elongation factors that assist the ribosome in binding the messenger RNA (mRNA), selecting the start codon, and synthesizing the polypeptide. We also examine mechanisms of translational control highlighting the mRNA cap-binding proteins and the regulation of GCN4 and CPA1 mRNAs.
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34
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eIF2B: recent structural and functional insights into a key regulator of translation. Biochem Soc Trans 2016; 43:1234-40. [PMID: 26614666 DOI: 10.1042/bst20150164] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The eukaryotic translation initiation factor (eIF) eIF2B is a key regulator of mRNA translation, being the guanine nt exchange factor (GEF) responsible for the recycling of the heterotrimeric G-protein, eIF2, which is required to allow translation initiation to occur. Unusually for a GEF, eIF2B is a multi-subunit protein, comprising five different subunits termed α through ε in order of increasing size. eIF2B is subject to tight regulation in the cell and may also serve additional functions. Here we review recent insights into the subunit organization of the mammalian eIF2B complex, gained both from structural studies of the complex and from studies of mutations of eIF2B that result in the neurological disorder leukoencephalopathy with vanishing white matter (VWM). We will also discuss recent data from yeast demonstrating a novel function of the eIF2B complex key for translational regulation.
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35
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Jennings MD, Kershaw CJ, White C, Hoyle D, Richardson JP, Costello JL, Donaldson IJ, Zhou Y, Pavitt GD. eIF2β is critical for eIF5-mediated GDP-dissociation inhibitor activity and translational control. Nucleic Acids Res 2016; 44:9698-9709. [PMID: 27458202 PMCID: PMC5175340 DOI: 10.1093/nar/gkw657] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 07/08/2016] [Accepted: 07/12/2016] [Indexed: 01/10/2023] Open
Abstract
In protein synthesis translation factor eIF2 binds initiator tRNA to ribosomes and facilitates start codon selection. eIF2 GDP/GTP status is regulated by eIF5 (GAP and GDI functions) and eIF2B (GEF and GDF activities), while eIF2α phosphorylation in response to diverse signals is a major point of translational control. Here we characterize a growth suppressor mutation in eIF2β that prevents eIF5 GDI and alters cellular responses to reduced eIF2B activity, including control of GCN4 translation. By monitoring the binding of fluorescent nucleotides and initiator tRNA to purified eIF2 we show that the eIF2β mutation does not affect intrinsic eIF2 affinities for these ligands, neither does it interfere with eIF2 binding to 43S pre-initiation complex components. Instead we show that the eIF2β mutation prevents eIF5 GDI stabilizing nucleotide binding to eIF2, thereby altering the off-rate of GDP from eIF2•GDP/eIF5 complexes. This enables cells to grow with reduced eIF2B GEF activity but impairs activation of GCN4 targets in response to amino acid starvation. These findings provide support for the importance of eIF5 GDI activity in vivo and demonstrate that eIF2β acts in concert with eIF5 to prevent premature release of GDP from eIF2γ and thereby ensure tight control of protein synthesis initiation.
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Affiliation(s)
- Martin D Jennings
- Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
| | - Christopher J Kershaw
- Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
| | - Christopher White
- Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
| | - Danielle Hoyle
- Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
| | - Jonathan P Richardson
- Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
| | - Joseph L Costello
- Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
| | - Ian J Donaldson
- Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
| | - Yu Zhou
- Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
| | - Graham D Pavitt
- Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
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Young SK, Wek RC. Upstream Open Reading Frames Differentially Regulate Gene-specific Translation in the Integrated Stress Response. J Biol Chem 2016; 291:16927-35. [PMID: 27358398 DOI: 10.1074/jbc.r116.733899] [Citation(s) in RCA: 243] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Translation regulation largely occurs during initiation, which features ribosome assembly onto mRNAs and selection of the translation start site. Short, upstream ORFs (uORFs) located in the 5'-leader of the mRNA can be selected for translation. Multiple transcripts associated with stress amelioration are preferentially translated through uORF-mediated mechanisms during activation of the integrated stress response (ISR) in which phosphorylation of the α subunit of eIF2 results in a coincident global reduction in translation initiation. This review presents key features of uORFs that serve to optimize translational control that is essential for regulation of cell fate in response to environmental stresses.
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Affiliation(s)
- Sara K Young
- From the Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202-5126
| | - Ronald C Wek
- From the Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202-5126
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Kuhle B, Eulig NK, Ficner R. Architecture of the eIF2B regulatory subcomplex and its implications for the regulation of guanine nucleotide exchange on eIF2. Nucleic Acids Res 2015; 43:9994-10014. [PMID: 26384431 PMCID: PMC4787765 DOI: 10.1093/nar/gkv930] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 09/07/2015] [Indexed: 11/14/2022] Open
Abstract
Eukaryal translation initiation factor 2B (eIF2B) acts as guanine nucleotide exchange factor (GEF) for eIF2 and forms a central target for pathways regulating global protein synthesis. eIF2B consists of five non-identical subunits (α-ϵ), which assemble into a catalytic subcomplex (γ, ϵ) responsible for the GEF activity, and a regulatory subcomplex (α, β, δ) which regulates the GEF activity under stress conditions. Here, we provide new structural and functional insight into the regulatory subcomplex of eIF2B (eIF2B(RSC)). We report the crystal structures of eIF2Bβ and eIF2Bδ from Chaetomium thermophilum as well as the crystal structure of their tetrameric eIF2B(βδ)2 complex. Combined with mutational and biochemical data, we show that eIF2B(RSC) exists as a hexamer in solution, consisting of two eIF2Bβδ heterodimers and one eIF2Bα2 homodimer, which is homologous to homohexameric ribose 1,5-bisphosphate isomerases. This homology is further substantiated by the finding that eIF2Bα specifically binds AMP and GMP as ligands. Based on our data, we propose a model for eIF2B(RSC) and its interactions with eIF2 that is consistent with previous biochemical and genetic data and provides a framework to better understand eIF2B function, the molecular basis for Gcn(-), Gcd(-) and VWM/CACH mutations and the evolutionary history of the eIF2B complex.
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Affiliation(s)
- Bernhard Kuhle
- Abteilung für Molekulare Strukturbiologie, Institut für Mikrobiologie und Genetik, Göttinger Zentrum für Molekulare Biowissenschaften, Georg-August-Universität Göttingen, D-37077 Göttingen, Germany
| | - Nora K Eulig
- Abteilung für Molekulare Strukturbiologie, Institut für Mikrobiologie und Genetik, Göttinger Zentrum für Molekulare Biowissenschaften, Georg-August-Universität Göttingen, D-37077 Göttingen, Germany
| | - Ralf Ficner
- Abteilung für Molekulare Strukturbiologie, Institut für Mikrobiologie und Genetik, Göttinger Zentrum für Molekulare Biowissenschaften, Georg-August-Universität Göttingen, D-37077 Göttingen, Germany
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38
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Sidrauski C, Tsai JC, Kampmann M, Hearn BR, Vedantham P, Jaishankar P, Sokabe M, Mendez AS, Newton BW, Tang EL, Verschueren E, Johnson JR, Krogan NJ, Fraser CS, Weissman JS, Renslo AR, Walter P. Pharmacological dimerization and activation of the exchange factor eIF2B antagonizes the integrated stress response. eLife 2015; 4:e07314. [PMID: 25875391 PMCID: PMC4426669 DOI: 10.7554/elife.07314] [Citation(s) in RCA: 178] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 04/13/2015] [Indexed: 12/18/2022] Open
Abstract
The general translation initiation factor eIF2 is a major translational control point. Multiple signaling pathways in the integrated stress response phosphorylate eIF2 serine-51, inhibiting nucleotide exchange by eIF2B. ISRIB, a potent drug-like small molecule, renders cells insensitive to eIF2α phosphorylation and enhances cognitive function in rodents by blocking long-term depression. ISRIB was identified in a phenotypic cell-based screen, and its mechanism of action remained unknown. We now report that ISRIB is an activator of eIF2B. Our reporter-based shRNA screen revealed an eIF2B requirement for ISRIB activity. Our results define ISRIB as a symmetric molecule, show ISRIB-mediated stabilization of activated eIF2B dimers, and suggest that eIF2B4 (δ-subunit) contributes to the ISRIB binding site. We also developed new ISRIB analogs, improving its EC50 to 600 pM in cell culture. By modulating eIF2B function, ISRIB promises to be an invaluable tool in proof-of-principle studies aiming to ameliorate cognitive defects resulting from neurodegenerative diseases.
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Affiliation(s)
- Carmela Sidrauski
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
| | - Jordan C Tsai
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
| | - Martin Kampmann
- Howard Hughes Medical Institution, University of California, San Francisco, San Francisco, United States
| | - Brian R Hearn
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United States
| | - Punitha Vedantham
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United States
| | - Priyadarshini Jaishankar
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United States
| | - Masaaki Sokabe
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of California, Davis, Davis, United States
| | - Aaron S Mendez
- Howard Hughes Medical Institution, University of California, San Francisco, San Francisco, United States
| | - Billy W Newton
- QB3, California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, United States
| | - Edward L Tang
- QB3, California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, United States
| | - Erik Verschueren
- QB3, California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, United States
| | - Jeffrey R Johnson
- QB3, California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, United States
| | - Nevan J Krogan
- QB3, California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, United States
| | - Christopher S Fraser
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of California, Davis, Davis, United States
| | - Jonathan S Weissman
- Howard Hughes Medical Institution, University of California, San Francisco, San Francisco, United States
| | - Adam R Renslo
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United States
| | - Peter Walter
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
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