1
|
Joshi K, Luisi B, Wunderlin G, Saleh S, Lilly A, Okusolubo T, Farabaugh PJ. An evolutionarily conserved phosphoserine-arginine salt bridge in the interface between ribosomal proteins uS4 and uS5 regulates translational accuracy in Saccharomyces cerevisiae. Nucleic Acids Res 2024; 52:3989-4001. [PMID: 38340338 DOI: 10.1093/nar/gkae053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 01/08/2024] [Accepted: 02/08/2024] [Indexed: 02/12/2024] Open
Abstract
Protein-protein and protein-rRNA interactions at the interface between ribosomal proteins uS4 and uS5 are thought to maintain the accuracy of protein synthesis by increasing selection of cognate aminoacyl-tRNAs. Selection involves a major conformational change-domain closure-that stabilizes aminoacyl-tRNA in the ribosomal acceptor (A) site. This has been thought a constitutive function of the ribosome ensuring consistent accuracy. Recently, the Saccharomyces cerevisiae Ctk1 cyclin-dependent kinase was demonstrated to ensure translational accuracy and Ser238 of uS5 proposed as its target. Surprisingly, Ser238 is outside the uS4-uS5 interface and no obvious mechanism has been proposed to explain its role. We show that the true target of Ctk1 regulation is another uS5 residue, Ser176, which lies in the interface opposite to Arg57 of uS4. Based on site specific mutagenesis, we propose that phospho-Ser176 forms a salt bridge with Arg57, which should increase selectivity by strengthening the interface. Genetic data show that Ctk1 regulates accuracy indirectly; the data suggest that the kinase Ypk2 directly phosphorylates Ser176. A second kinase pathway involving TORC1 and Pkc1 can inhibit this effect. The level of accuracy appears to depend on competitive action of these two pathways to regulate the level of Ser176 phosphorylation.
Collapse
Affiliation(s)
- Kartikeya Joshi
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Brooke Luisi
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Grant Wunderlin
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Sima Saleh
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Anna Lilly
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Temiloluwa Okusolubo
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Philip J Farabaugh
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| |
Collapse
|
2
|
Hochstoeger T, Chao JA. Towards a molecular understanding of the 5'TOP motif in regulating translation of ribosomal mRNAs. Semin Cell Dev Biol 2024; 154:99-104. [PMID: 37316417 DOI: 10.1016/j.semcdb.2023.06.001] [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: 05/20/2022] [Revised: 04/14/2023] [Accepted: 06/05/2023] [Indexed: 06/16/2023]
Abstract
Vertebrate cells have evolved a simple, yet elegant, mechanism for coordinated regulation of ribosome biogenesis mediated by the 5' terminal oligopyrimidine motif (5'TOP). This motif allows cells to rapidly adapt to changes in the environment by specifically modulating translation rate of mRNAs encoding the translation machinery. Here, we provide an overview of the origin of this motif, its characterization, and progress in identifying the key regulatory factors involved. We highlight challenges in the field of 5'TOP research, and discuss future approaches that we think will be able to resolve outstanding questions.
Collapse
Affiliation(s)
- Tobias Hochstoeger
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland; University of Basel, 4003 Basel, Switzerland
| | - Jeffrey A Chao
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland.
| |
Collapse
|
3
|
McColl TJ, Clarke DC. Kinetic modeling of leucine-mediated signaling and protein metabolism in human skeletal muscle. iScience 2024; 27:108634. [PMID: 38188514 PMCID: PMC10767222 DOI: 10.1016/j.isci.2023.108634] [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] [Received: 06/12/2023] [Revised: 11/15/2023] [Accepted: 12/01/2023] [Indexed: 01/09/2024] Open
Abstract
Skeletal muscle protein levels are governed by the relative rates of muscle protein synthesis (MPS) and breakdown (MPB). The mechanisms controlling these rates are complex, and their integrated behaviors are challenging to study through experiments alone. The purpose of this study was to develop and analyze a kinetic model of leucine-mediated mTOR signaling and protein metabolism in the skeletal muscle of young adults. Our model amalgamates published cellular-level models of the IRS1-PI3K-Akt-mTORC1 signaling system and of skeletal-muscle leucine kinetics with physiological-level models of leucine digestion and transport and insulin dynamics. The model satisfactorily predicts experimental data from diverse leucine feeding protocols. Model analysis revealed that total levels of p70S6K are a primary determinant of MPS, insulin signaling substantially affects muscle net protein balance via its effects on MPB, and p70S6K-mediated feedback of mTORC1 signaling reduces MPS in a dose-dependent manner.
Collapse
Affiliation(s)
- Taylor J. McColl
- Department of Biomedical Physiology and KinesiologySimon Fraser University, Burnaby, BC V5A 1S6, Canada
- Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - David C. Clarke
- Department of Biomedical Physiology and KinesiologySimon Fraser University, Burnaby, BC V5A 1S6, Canada
- Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| |
Collapse
|
4
|
Gomez Ramos B, Ohnmacht J, de Lange N, Valceschini E, Ginolhac A, Catillon M, Ferrante D, Rakovic A, Halder R, Massart F, Arena G, Antony P, Bolognin S, Klein C, Krause R, Schulz MH, Sauter T, Krüger R, Sinkkonen L. Multiomics analysis identifies novel facilitators of human dopaminergic neuron differentiation. EMBO Rep 2024; 25:254-285. [PMID: 38177910 PMCID: PMC10897179 DOI: 10.1038/s44319-023-00024-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 11/17/2023] [Accepted: 11/23/2023] [Indexed: 01/06/2024] Open
Abstract
Midbrain dopaminergic neurons (mDANs) control voluntary movement, cognition, and reward behavior under physiological conditions and are implicated in human diseases such as Parkinson's disease (PD). Many transcription factors (TFs) controlling human mDAN differentiation during development have been described, but much of the regulatory landscape remains undefined. Using a tyrosine hydroxylase (TH) human iPSC reporter line, we here generate time series transcriptomic and epigenomic profiles of purified mDANs during differentiation. Integrative analysis predicts novel regulators of mDAN differentiation and super-enhancers are used to identify key TFs. We find LBX1, NHLH1 and NR2F1/2 to promote mDAN differentiation and show that overexpression of either LBX1 or NHLH1 can also improve mDAN specification. A more detailed investigation of TF targets reveals that NHLH1 promotes the induction of neuronal miR-124, LBX1 regulates cholesterol biosynthesis, and NR2F1/2 controls neuronal activity.
Collapse
Affiliation(s)
- Borja Gomez Ramos
- Department of Life Sciences and Medicine (DLSM), University of Luxembourg, L-4362, Belvaux, Luxembourg
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Jochen Ohnmacht
- Department of Life Sciences and Medicine (DLSM), University of Luxembourg, L-4362, Belvaux, Luxembourg
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Nikola de Lange
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Elena Valceschini
- Department of Life Sciences and Medicine (DLSM), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Aurélien Ginolhac
- Department of Life Sciences and Medicine (DLSM), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Marie Catillon
- Department of Life Sciences and Medicine (DLSM), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Daniele Ferrante
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Aleksandar Rakovic
- Institute of Neurogenetics, University of Lübeck, 23538, Lübeck, Germany
| | - Rashi Halder
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - François Massart
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Giuseppe Arena
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Paul Antony
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Silvia Bolognin
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, 23538, Lübeck, Germany
| | - Roland Krause
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Marcel H Schulz
- Institute for Cardiovascular Regeneration, Goethe University, 60590, Frankfurt, Germany
- German Centre for Cardiovascular Research, Partner site Rhein-Main, 60590, Frankfurt am Main, Germany
- Cardio-Pulmonary Institute, Goethe University, Frankfurt am Main, Germany
| | - Thomas Sauter
- Department of Life Sciences and Medicine (DLSM), University of Luxembourg, L-4362, Belvaux, Luxembourg
| | - Rejko Krüger
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362, Belvaux, Luxembourg
- Centre Hospitalier de Luxembourg (CHL), L-1210, Luxembourg, Luxembourg
- Luxembourg Institute of Health (LIH), L-1445, Luxembourg, Luxembourg
| | - Lasse Sinkkonen
- Department of Life Sciences and Medicine (DLSM), University of Luxembourg, L-4362, Belvaux, Luxembourg.
| |
Collapse
|
5
|
Gahurova L, Tomankova J, Cerna P, Bora P, Kubickova M, Virnicchi G, Kovacovicova K, Potesil D, Hruska P, Zdrahal Z, Anger M, Susor A, Bruce AW. Spatial positioning of preimplantation mouse embryo cells is regulated by mTORC1 and m 7G-cap-dependent translation at the 8- to 16-cell transition. Open Biol 2023; 13:230081. [PMID: 37553074 PMCID: PMC10409569 DOI: 10.1098/rsob.230081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 07/18/2023] [Indexed: 08/10/2023] Open
Abstract
Preimplantation mouse embryo development involves temporal-spatial specification and segregation of three blastocyst cell lineages: trophectoderm, primitive endoderm and epiblast. Spatial separation of the outer-trophectoderm lineage from the two other inner-cell-mass (ICM) lineages starts with the 8- to 16-cell transition and concludes at the 32-cell stages. Accordingly, the ICM is derived from primary and secondary contributed cells; with debated relative EPI versus PrE potencies. We report generation of primary but not secondary ICM populations is highly dependent on temporal activation of mammalian target of Rapamycin (mTOR) during 8-cell stage M-phase entry, mediated via regulation of the 7-methylguanosine-cap (m7G-cap)-binding initiation complex (EIF4F) and linked to translation of mRNAs containing 5' UTR terminal oligopyrimidine (TOP-) sequence motifs, as knockdown of identified TOP-like motif transcripts impairs generation of primary ICM founders. However, mTOR inhibition-induced ICM cell number deficits in early blastocysts can be compensated by the late blastocyst stage, after inhibitor withdrawal; compensation likely initiated at the 32-cell stage when supernumerary outer cells exhibit molecular characteristics of inner cells. These data identify a novel mechanism specifically governing initial spatial segregation of mouse embryo blastomeres, that is distinct from those directing subsequent inner cell formation, contributing to germane segregation of late blastocyst lineages.
Collapse
Affiliation(s)
- Lenka Gahurova
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 27721 Liběchov, Czech Republic
| | - Jana Tomankova
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Pavlina Cerna
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Pablo Bora
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Michaela Kubickova
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Giorgio Virnicchi
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Kristina Kovacovicova
- Laboratory of Cell Division Control, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 27721 Liběchov, Czech Republic
- Department of Genetics and Reproduction, Central European Institute of Technology, Veterinary Research Institute, Hudcova 296/70, 621 00 Brno, Czech Republic
| | - David Potesil
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Pavel Hruska
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Zbynek Zdrahal
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Martin Anger
- Laboratory of Cell Division Control, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 27721 Liběchov, Czech Republic
- Department of Genetics and Reproduction, Central European Institute of Technology, Veterinary Research Institute, Hudcova 296/70, 621 00 Brno, Czech Republic
| | - Andrej Susor
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 27721 Liběchov, Czech Republic
| | - Alexander W. Bruce
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| |
Collapse
|
6
|
Artoni F, Grützmacher N, Demetriades C. Unbiased evaluation of rapamycin's specificity as an mTOR inhibitor. Aging Cell 2023; 22:e13888. [PMID: 37222020 PMCID: PMC10410055 DOI: 10.1111/acel.13888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 05/02/2023] [Accepted: 05/07/2023] [Indexed: 05/25/2023] Open
Abstract
Rapamycin is a macrolide antibiotic that functions as an immunosuppressive and anti-cancer agent, and displays robust anti-ageing effects in multiple organisms including humans. Importantly, rapamycin analogues (rapalogs) are of clinical importance against certain cancer types and neurodevelopmental diseases. Although rapamycin is widely perceived as an allosteric inhibitor of mTOR (mechanistic target of rapamycin), the master regulator of cellular and organismal physiology, its specificity has not been thoroughly evaluated so far. In fact, previous studies in cells and in mice hinted that rapamycin may be also acting independently from mTOR to influence various cellular processes. Here, we generated a gene-edited cell line that expresses a rapamycin-resistant mTOR mutant (mTORRR ) and assessed the effects of rapamycin treatment on the transcriptome and proteome of control or mTORRR -expressing cells. Our data reveal a striking specificity of rapamycin towards mTOR, demonstrated by virtually no changes in mRNA or protein levels in rapamycin-treated mTORRR cells, even following prolonged drug treatment. Overall, this study provides the first unbiased and conclusive assessment of rapamycin's specificity, with potential implications for ageing research and human therapeutics.
Collapse
Affiliation(s)
- Filippo Artoni
- Max Planck Institute for Biology of Ageing (MPI‐AGE)CologneGermany
- Cologne Graduate School of Ageing Research (CGA)CologneGermany
| | - Nina Grützmacher
- Max Planck Institute for Biology of Ageing (MPI‐AGE)CologneGermany
| | - Constantinos Demetriades
- Max Planck Institute for Biology of Ageing (MPI‐AGE)CologneGermany
- Cologne Graduate School of Ageing Research (CGA)CologneGermany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging‐Associated Diseases (CECAD)University of CologneCologneGermany
| |
Collapse
|
7
|
Folgado-Marco V, Ames K, Chuen J, Gritsman K, Baker NE. Haploinsufficiency of the essential gene Rps12 causes defects in erythropoiesis and hematopoietic stem cell maintenance. eLife 2023; 12:e69322. [PMID: 37272618 PMCID: PMC10287158 DOI: 10.7554/elife.69322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 04/26/2023] [Indexed: 06/06/2023] Open
Abstract
Ribosomal protein (Rp) gene haploinsufficiency can result in Diamond-Blackfan Anemia (DBA), characterized by defective erythropoiesis and skeletal defects. Some mouse Rp mutations recapitulate DBA phenotypes, although others lack erythropoietic or skeletal defects. We generated a conditional knockout mouse to partially delete Rps12. Homozygous Rps12 deletion resulted in embryonic lethality. Mice inheriting the Rps12KO/+ genotype had growth and morphological defects, pancytopenia, and impaired erythropoiesis. A striking reduction in hematopoietic stem cells (HSCs) and progenitors in the bone marrow (BM) was associated with decreased ability to repopulate the blood system after competitive and non-competitive BM transplantation. Rps12KO/+ lost HSC quiescence, experienced ERK and MTOR activation, and increased global translation in HSC and progenitors. Post-natal heterozygous deletion of Rps12 in hematopoietic cells using Tal1-Cre-ERT also resulted in pancytopenia with decreased HSC numbers. However, post-natal Cre-ERT induction led to reduced translation in HSCs and progenitors, suggesting that this is the most direct consequence of Rps12 haploinsufficiency in hematopoietic cells. Thus, RpS12 has a strong requirement in HSC function, in addition to erythropoiesis.
Collapse
Affiliation(s)
| | - Kristina Ames
- Department of Medical Oncology, Albert Einstein College of MedicineBronxUnited States
- Department of Cell Biology, Albert Einstein College of MedicineBronxUnited States
| | - Jacky Chuen
- Department of Genetics, Albert Einstein College of MedicineBronxUnited States
| | - Kira Gritsman
- Department of Medical Oncology, Albert Einstein College of MedicineBronxUnited States
- Department of Cell Biology, Albert Einstein College of MedicineBronxUnited States
| | - Nicholas E Baker
- Department of Genetics, Albert Einstein College of MedicineBronxUnited States
| |
Collapse
|
8
|
Sidhaye J, Trepte P, Sepke N, Novatchkova M, Schutzbier M, Dürnberger G, Mechtler K, Knoblich JA. Integrated transcriptome and proteome analysis reveals posttranscriptional regulation of ribosomal genes in human brain organoids. eLife 2023; 12:85135. [PMID: 36989136 PMCID: PMC10059687 DOI: 10.7554/elife.85135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 03/16/2023] [Indexed: 03/30/2023] Open
Abstract
During development of the human cerebral cortex, multipotent neural progenitors generate excitatory neurons and glial cells. Investigations of the transcriptome and epigenome have revealed important gene regulatory networks underlying this crucial developmental event. However, the posttranscriptional control of gene expression and protein abundance during human corticogenesis remains poorly understood. We addressed this issue by using human telencephalic brain organoids grown using a dual reporter cell line to isolate neural progenitors and neurons and performed cell class and developmental stage-specific transcriptome and proteome analysis. Integrating the two datasets revealed modules of gene expression during human corticogenesis. Investigation of one such module uncovered mTOR-mediated regulation of translation of the 5'TOP element-enriched translation machinery in early progenitor cells. We show that in early progenitors partial inhibition of the translation of ribosomal genes prevents precocious translation of differentiation markers. Overall, our multiomics approach proposes novel posttranscriptional regulatory mechanisms crucial for the fidelity of cortical development.
Collapse
Affiliation(s)
- Jaydeep Sidhaye
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Philipp Trepte
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Natalie Sepke
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Maria Novatchkova
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | | | | | - Karl Mechtler
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Jürgen A Knoblich
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
- Department of Neurology, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
9
|
Ma X, Jia Q, Li S, Chen Z, Ming X, Zhao Y, Zhou DX. An enhanced network of energy metabolism, lysine acetylation, and growth-promoting protein accumulation is associated with heterosis in elite hybrid rice. PLANT COMMUNICATIONS 2023:100560. [PMID: 36774536 PMCID: PMC10363507 DOI: 10.1016/j.xplc.2023.100560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/08/2022] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
Heterosis refers to the superior performance of a hybrid compared with its parental lines. Although several genetic and molecular models have been proposed to explain heterosis, it remains unclear how hybrid cells integrate complementary gene expression or activity to drive heterotic growth. In this work, we show that accumulation of growth-promoting and energy metabolism proteins, enhanced energy metabolism activities, and increased protein lysine acetylation were associated with superior growth of the panicle meristem in the elite hybrid rice Shanyou 63 relative to its parental varieties. Metabolism of nuclear/cytosolic acetyl-coenzyme A was also enhanced in the hybrid, which paralleled increases in histone H3 acetylation to selectively target the expression of growth-promoting and metabolic genes. Lysine acetylation of cellular proteins, including TARGET OF RAPAMYCIN complex 1, ribosomal proteins, and energy metabolism enzymes, was also augmented and/or remodeled to modulate their activities. The data indicate that an enhanced network of energy-producing metabolic activity and growth-promoting histone acetylation/gene expression in the hybrid could contribute to its superior growth rate and may constitute a model to explain heterosis.
Collapse
Affiliation(s)
- Xuan Ma
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Qingxiao Jia
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Sheng Li
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhengting Chen
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Xin Ming
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Yu Zhao
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Dao-Xiu Zhou
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; Institute of Plant Science Paris-Saclay (IPS2), CNRS, INRAE, University Paris-Saclay, 91405 Orsay, France.
| |
Collapse
|
10
|
Bakshi A, Moin M, Gayatri MB, Reddy ABM, Datla R, Madhav MS, Kirti PB. Involvement of Target of Rapamycin (TOR) Signaling in the Regulation of Crosstalk between Ribosomal Protein Small Subunit 6 Kinase-1 (RPS6K-1) and Ribosomal Proteins. PLANTS (BASEL, SWITZERLAND) 2023; 12:176. [PMID: 36616305 PMCID: PMC9824793 DOI: 10.3390/plants12010176] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/26/2022] [Accepted: 12/27/2022] [Indexed: 06/17/2023]
Abstract
The target of rapamycin (TOR) protein phosphorylates its downstream effector p70kDa ribosomal protein S6 kinases (S6K1) for ribosome biogenesis and translation initiation in eukaryotes. However, the molecular mechanism of TOR-S6K1-ribosomal protein (RP) signaling is not well understood in plants. In the present study, we report the transcriptional upregulation of ribosomal protein large and small subunit (RPL and RPS) genes in the previously established TOR overexpressing transgenic lines of rice (in Oryza sativa ssp. indica, variety BPT-5204, TR-2.24 and TR-15.1) and of Arabidopsis thaliana (in Col 0 ecotype, ATR-1.4.27 and ATR-3.7.32). The mRNA levels of RP genes from this study were compared with those previously available in transcriptomic datasets on the expression of RPs in relation to TOR inhibitor and in the TOR-RNAi lines of Arabidopsis thaliana. We further analyzed TOR activity, i.e., S6K1 phosphorylation in SALK lines of Arabidopsis with mutation in rpl6, rpl18, rpl23, rpl24 and rps28C, where the rpl18 mutant showed inactivation of S6K1 phosphorylation. We also predicted similar putative Ser/Thr phosphorylation sites for ribosomal S6 kinases (RSKs) in the RPs of Oryza sativa ssp. indica and Arabidopsis thaliana. The findings of this study indicate that the TOR pathway is possibly interlinked in a cyclic manner via the phosphorylation of S6K1 as a modulatory step for the regulation of RP function to switch 'on'/'off' the translational regulation for balanced plant growth.
Collapse
Affiliation(s)
- Achala Bakshi
- Indian Institute of Rice Research, Rajendranagar, Hyderabad 500030, Telangana, India
- Global Institute for Food Security, Saskatoon, SK S7N 0W9, Canada
| | - Mazahar Moin
- Indian Institute of Rice Research, Rajendranagar, Hyderabad 500030, Telangana, India
- Agri Biotech Foundation, PJTS Agricultural University Campus, Rajendranagar, Hyderabad 500030, Telangana, India
| | - Meher B. Gayatri
- Department of Animal Biology, University of Hyderabad, Hyderabad 500046, Telangana, India
| | - Aramati B. M. Reddy
- Department of Animal Biology, University of Hyderabad, Hyderabad 500046, Telangana, India
| | - Raju Datla
- Global Institute for Food Security, Saskatoon, SK S7N 0W9, Canada
| | - Maganti S. Madhav
- Indian Institute of Rice Research, Rajendranagar, Hyderabad 500030, Telangana, India
- Central Tobacco Research Institute, Rajahmundry 533105, Andhra Pradesh, India
| | - Pulugurtha B. Kirti
- Agri Biotech Foundation, PJTS Agricultural University Campus, Rajendranagar, Hyderabad 500030, Telangana, India
- Department of Plant Sciences, University of Hyderabad, Hyderabad 500046, Telangana, India
| |
Collapse
|
11
|
Abstract
C-Myc overexpression is a common finding in pancreatic cancer and predicts the aggressive behavior of cancer cells. It binds to the promoter of different genes, thereby regulating their transcription. C-Myc is downstream of KRAS and interacts with several oncogenic and proliferative pathways in pancreatic cancer. C-Myc enhances aerobic glycolysis in cancer cells and regulates glutamate biosynthesis from glutamine. It provides enough energy for cancer cells' metabolism and sufficient substrate for the synthesis of organic molecules. C-Myc overexpression is associated with chemoresistance, intra-tumor angiogenesis, epithelial-mesenchymal transition (EMT), and metastasis in pancreatic cancer. Despite its title, c-Myc is not "undruggable" and recent studies unveiled that it can be targeted, directly or indirectly. Small molecules that accelerate c-Myc ubiquitination and degradation have been effective in preclinical studies. Small molecules that hinder c-Myc-MAX heterodimerization or c-Myc/MAX/DNA complex formation can functionally inhibit c-Myc. In addition, c-Myc can be targeted through transcriptional, post-transcriptional, and translational modifications.
Collapse
Affiliation(s)
- Moein Ala
- School of Medicine, Tehran University of Medical Sciences (TUMS), Tehran, Iran
| |
Collapse
|
12
|
Gale JR, Gedeon JY, Donnelly CJ, Gold MS. Local translation in primary afferents and its contribution to pain. Pain 2022; 163:2302-2314. [PMID: 35438669 PMCID: PMC9579217 DOI: 10.1097/j.pain.0000000000002658] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 04/08/2022] [Indexed: 02/06/2023]
Abstract
ABSTRACT Chronic pain remains a significant problem due to its prevalence, impact, and limited therapeutic options. Progress in addressing chronic pain is dependent on a better understanding of underlying mechanisms. Although the available evidence suggests that changes within the central nervous system contribute to the initiation and maintenance of chronic pain, it also suggests that the primary afferent plays a critical role in all phases of the manifestation of chronic pain in most of those who suffer. Most notable among the changes in primary afferents is an increase in excitability or sensitization. A number of mechanisms have been identified that contribute to primary afferent sensitization with evidence for both increases in pronociceptive signaling molecules, such as voltage-gated sodium channels, and decreases in antinociceptive signaling molecules, such as voltage-dependent or calcium-dependent potassium channels. Furthermore, these changes in signaling molecules seem to reflect changes in gene expression as well as posttranslational processing. A mechanism of sensitization that has received far less attention, however, is the local or axonal translation of these signaling molecules. A growing body of evidence indicates that this process not only is dynamically regulated but also contributes to the initiation and maintenance of chronic pain. Here, we review the biology of local translation in primary afferents and its relevance to pain pathobiology.
Collapse
Affiliation(s)
- Jenna R Gale
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Jeremy Y Gedeon
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | | | - Michael S Gold
- Corresponding author: Michael S Gold, PhD, Department of Neurobiology, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 15213, P: 412-383-5367,
| |
Collapse
|
13
|
Minichino D, Lv K, Chu N, Tong W, Behrens EM. BRAF-V600E utilizes posttranscriptional mechanisms to amplify LPS-induced TNFα production in dendritic cells in a mouse model of Langerhans cell histiocytosis. J Leukoc Biol 2022; 112:1089-1104. [PMID: 35648675 PMCID: PMC9939017 DOI: 10.1002/jlb.3a0122-075rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 04/25/2022] [Indexed: 12/24/2022] Open
Abstract
Langerhans cell histiocytosis (LCH) is an inflammatory disease characterized by abnormal dendritic cells (DCs) with hyperactive ERK signaling, called "LCH cells." Since DCs rely on ERK signaling to produce inflammatory molecules in response to pathogenic cues, we hypothesized that hyperactive ERK enhances DCs inflammatory responses. We specifically investigated TLR4-induced TNFα production in LCH cells by utilizing the BRAF-V600Efl/+ :CD11c-Cre mouse model of LCH, which hyperactivates ERK in DCs. We measured LPS-induced TNFα production both in vivo and in vitro using splenic CD11c+ cells and bone marrow-derived DCs with or without pharmacologic BRAFV600E inhibition. We observed a reversible increase in secreted TNFα and a partially reversible increase in TNFα protein per cell, despite a decrease in TLR4 signaling and Tnfa transcripts compared with controls. We examined ERK-driven, posttranscriptional mechanisms that contribute to TNFα production and secretion using biochemical and cellular assays. We identified a reversible increase in TACE activation, the enzyme required for TNFα secretion, and most strikingly, an increase in protein translation, including TNFα. Defining the translatome through polysome-bound RNA sequencing revealed up-regulated translation of the LPS-response program. These data suggest hyperactive ERK signaling utilizes multiple posttranscriptional mechanisms to amplify inflammatory responses in DCs, advancing our understanding of LCH and basic DC biology.
Collapse
Affiliation(s)
- Danielle Minichino
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Pediatric Rheumatology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Kaosheng Lv
- Division of Hematology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Niansheng Chu
- Division of Pediatric Rheumatology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Wei Tong
- Division of Hematology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Edward M Behrens
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Pediatric Rheumatology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| |
Collapse
|
14
|
Peters NA, Constantinides A, Ubink I, van Kuik J, Bloemendal HJ, van Dodewaard JM, Brink MA, Schwartz TP, Lolkema MP, Lacle MM, Moons LM, Geesing J, van Grevenstein WM, Roodhart JML, Koopman M, Elias SG, Borel Rinkes IH, Kranenburg O. Consensus molecular subtype 4 (CMS4)-targeted therapy in primary colon cancer: A proof-of-concept study. Front Oncol 2022; 12:969855. [PMID: 36147916 PMCID: PMC9486194 DOI: 10.3389/fonc.2022.969855] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 08/19/2022] [Indexed: 11/13/2022] Open
Abstract
BackgroundMesenchymal Consensus Molecular Subtype 4 (CMS4) colon cancer is associated with poor prognosis and therapy resistance. In this proof-of-concept study, we assessed whether a rationally chosen drug could mitigate the distinguishing molecular features of primary CMS4 colon cancer.MethodsIn the ImPACCT trial, informed consent was obtained for molecular subtyping at initial diagnosis of colon cancer using a validated RT-qPCR CMS4-test on three biopsies per tumor (Phase-1, n=69 patients), and for neoadjuvant CMS4-targeting therapy with imatinib (Phase-2, n=5). Pre- and post-treatment tumor biopsies were analyzed by RNA-sequencing and immunohistochemistry. Imatinib-induced gene expression changes were associated with molecular subtypes and survival in an independent cohort of 3232 primary colon cancer.ResultsThe CMS4-test classified 52/172 biopsies as CMS4 (30%). Five patients consented to imatinib treatment prior to surgery, yielding 15 pre- and 15 post-treatment samples for molecular analysis. Imatinib treatment caused significant suppression of mesenchymal genes and upregulation of genes encoding epithelial junctions. The gene expression changes induced by imatinib were associated with improved survival and a shift from CMS4 to CMS2.ConclusionImatinib may have value as a CMS-switching drug in primary colon cancer and induces a gene expression program that is associated with improved survival.
Collapse
Affiliation(s)
- Niek A. Peters
- Lab Translational Oncology, Division of Imaging and Cancer, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Alexander Constantinides
- Lab Translational Oncology, Division of Imaging and Cancer, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Inge Ubink
- Lab Translational Oncology, Division of Imaging and Cancer, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Joyce van Kuik
- Department of Pathology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Haiko J. Bloemendal
- Department of Internal Medicine, Meander Medical Center, Amersfoort, Netherlands
- Department of Internal Medicine/Oncology, Radboud University Medical Center Nijmegen, Nijmegen, Netherlands
| | | | - Menno A. Brink
- Department of Gastroenterology, Meander Medical Center, Amersfoort, Netherlands
| | - Thijs P. Schwartz
- Department of Gastroenterology, Meander Medical Center, Amersfoort, Netherlands
| | | | - Miangela M. Lacle
- Department of Pathology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Leon M. Moons
- Department of Gastroenterology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Joost Geesing
- Department of Gastroenterology, Diakonessenhuis, Utrecht, Netherlands
| | - Wilhelmina M.U. van Grevenstein
- Department of Surgical Oncology, Division of Imaging and Cancer, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Jeanine M. L. Roodhart
- Lab Translational Oncology, Division of Imaging and Cancer, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
- Department of Medical Oncology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Miriam Koopman
- Department of Medical Oncology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Sjoerd G. Elias
- Julius Centre for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Inne H.M. Borel Rinkes
- Lab Translational Oncology, Division of Imaging and Cancer, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
- Department of Surgical Oncology, Division of Imaging and Cancer, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
- *Correspondence: Inne H.M. Borel Rinkes, ; Onno Kranenburg,
| | - Onno Kranenburg
- Lab Translational Oncology, Division of Imaging and Cancer, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
- *Correspondence: Inne H.M. Borel Rinkes, ; Onno Kranenburg,
| |
Collapse
|
15
|
Kauer SD, Fink KL, Li EHF, Evans BP, Golan N, Cafferty WBJ. Inositol Polyphosphate-5-Phosphatase K ( Inpp5k) Enhances Sprouting of Corticospinal Tract Axons after CNS Trauma. J Neurosci 2022; 42:2190-2204. [PMID: 35135857 PMCID: PMC8936595 DOI: 10.1523/jneurosci.0897-21.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 01/13/2022] [Accepted: 01/14/2022] [Indexed: 11/21/2022] Open
Abstract
Failure of CNS neurons to mount a significant growth response after trauma contributes to chronic functional deficits after spinal cord injury. Activator and repressor screening of embryonic cortical neurons and retinal ganglion cells in vitro and transcriptional profiling of developing CNS neurons harvested in vivo have identified several candidates that stimulate robust axon growth in vitro and in vivo Building on these studies, we sought to identify novel axon growth activators induced in the complex adult CNS environment in vivo We transcriptionally profiled intact sprouting adult corticospinal neurons (CSNs) after contralateral pyramidotomy (PyX) in nogo receptor-1 knock-out mice and found that intact CSNs were enriched in genes in the 3-phosphoinositide degradation pathway, including six 5-phosphatases. We explored whether inositol polyphosphate-5-phosphatase K (Inpp5k) could enhance corticospinal tract (CST) axon growth in preclinical models of acute and chronic CNS trauma. Overexpression of Inpp5k in intact adult CSNs in male and female mice enhanced the sprouting of intact CST terminals after PyX and cortical stroke and sprouting of CST axons after acute and chronic severe thoracic spinal contusion. We show that Inpp5k stimulates axon growth in part by elevating the density of active cofilin in labile growth cones, thus stimulating actin polymerization and enhancing microtubule protrusion into distal filopodia. We identify Inpp5k as a novel CST growth activator capable of driving compensatory axon growth in multiple complex CNS injury environments and underscores the veracity of using in vivo transcriptional screening to identify the next generation of cell-autonomous factors capable of repairing the damaged CNS.SIGNIFICANCE STATEMENT Neurologic recovery is limited after spinal cord injury as CNS neurons are incapable of self-repair post-trauma. In vitro screening strategies exploit the intrinsically high growth capacity of embryonic CNS neurons to identify novel axon growth activators. While promising candidates have been shown to stimulate axon growth in vivo, concomitant functional recovery remains incomplete. We identified Inpp5k as a novel axon growth activator using transcriptional profiling of intact adult corticospinal tract (CST) neurons that had initiated a growth response after pyramidotomy in plasticity sensitized nogo receptor-1-null mice. Here, we show that Inpp5k overexpression can stimulate CST axon growth after pyramidotomy, stroke, and acute and chronic contusion injuries. These data support in vivo screening approaches to identify novel axon growth activators.
Collapse
Affiliation(s)
- Sierra D Kauer
- Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Kathryn L Fink
- Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Elizabeth H F Li
- Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Brian P Evans
- Regeneron Pharmaceuticals, Tarrytown, New York 10591
| | - Noa Golan
- Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06520
| | - William B J Cafferty
- Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06520
| |
Collapse
|
16
|
Sarkar AK, Sadhukhan S. Imperative role of trehalose metabolism and trehalose-6-phosphate signaling on salt stress responses in plants. PHYSIOLOGIA PLANTARUM 2022; 174:e13647. [PMID: 35141895 DOI: 10.1111/ppl.13647] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 01/23/2022] [Accepted: 02/07/2022] [Indexed: 05/04/2023]
Abstract
Sugar transport and distribution have a direct impact on the growth and development of plants. Many sugars significantly influence salt stress response. The sensing of salt stress signals triggers a wide array of complicated network transduction pathways in plants. Trehalose and its intermediate compounds effectively modulate salt response and salt tolerance. Sugars such as trehalose and its derivatives not only serve as metabolic resources and structural components of cells in plants but also exhibit hormone-like regulating properties. Trehalose has an important physiological role in improving plant tolerance against salinity stresses in different plants. Plants finely adjust their cytoplasmic compatible solute pool to cope with high salinity. Salt stress induces a variety of structural, anatomical, molecular, biochemical, and physiological changes in plants, all of which have a detrimental influence on plant growth and development. This review highlights the recent developments in understanding trehalose and trehalose-6-phosphate signaling processes in plants, especially their impacts on plants growing in salty environments.
Collapse
Affiliation(s)
- Anup Kumar Sarkar
- Department of Botany, Dukhulal Nibaran Chandra College, Murshidabad, West Bengal, India
- Plant Molecular Biology Laboratory, Department of Botany, Raiganj University, Raiganj, West Bengal, India
| | - Sanjoy Sadhukhan
- Plant Molecular Biology Laboratory, Department of Botany, Raiganj University, Raiganj, West Bengal, India
| |
Collapse
|
17
|
Deregulation of ribosomal proteins in human cancers. Biosci Rep 2021; 41:230380. [PMID: 34873618 PMCID: PMC8685657 DOI: 10.1042/bsr20211577] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 10/28/2021] [Accepted: 11/22/2021] [Indexed: 12/26/2022] Open
Abstract
The ribosome, the site for protein synthesis, is composed of ribosomal RNAs (rRNAs) and ribosomal proteins (RPs). The latter have been shown to have many ribosomal and extraribosomal functions. RPs are implicated in a variety of pathological processes, especially tumorigenesis and cell transformation. In this review, we will focus on the recent advances that shed light on the effects of RPs deregulation in different types of cancer and their roles in regulating the tumor cell fate.
Collapse
|
18
|
Li C, Li K, Li K, Ai K, Zhang Y, Zhang J, Li J, Wei X, Yang J. Essential role of 4E-BP1 for lymphocyte activation and proliferation in the adaptive immune response of Nile tilapia. FISH AND SHELLFISH IMMUNOLOGY REPORTS 2021; 2:100006. [DOI: 10.1016/j.fsirep.2021.100006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 02/04/2021] [Accepted: 02/11/2021] [Indexed: 12/14/2022] Open
|
19
|
p38-MAPK-mediated translation regulation during early blastocyst development is required for primitive endoderm differentiation in mice. Commun Biol 2021; 4:788. [PMID: 34172827 PMCID: PMC8233355 DOI: 10.1038/s42003-021-02290-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 06/02/2021] [Indexed: 02/07/2023] Open
Abstract
Successful specification of the two mouse blastocyst inner cell mass (ICM) lineages (the primitive endoderm (PrE) and epiblast) is a prerequisite for continued development and requires active fibroblast growth factor 4 (FGF4) signaling. Previously, we identified a role for p38 mitogen-activated protein kinases (p38-MAPKs) during PrE differentiation, but the underlying mechanisms have remained unresolved. Here, we report an early blastocyst window of p38-MAPK activity that is required to regulate ribosome-related gene expression, rRNA precursor processing, polysome formation and protein translation. We show that p38-MAPK inhibition-induced PrE phenotypes can be partially rescued by activating the translational regulator mTOR. However, similar PrE phenotypes associated with extracellular signal-regulated kinase (ERK) pathway inhibition targeting active FGF4 signaling are not affected by mTOR activation. These data indicate a specific role for p38-MAPKs in providing a permissive translational environment during mouse blastocyst PrE differentiation that is distinct from classically reported FGF4-based mechanisms.
Collapse
|
20
|
Jia JJ, Lahr RM, Solgaard MT, Moraes BJ, Pointet R, Yang AD, Celucci G, Graber TE, Hoang HD, Niklaus M, Pena IA, Hollensen AK, Smith EM, Chaker-Margot M, Anton L, Dajadian C, Livingstone M, Hearnden J, Wang XD, Yu Y, Maier T, Damgaard CK, Berman AJ, Alain T, Fonseca BD. mTORC1 promotes TOP mRNA translation through site-specific phosphorylation of LARP1. Nucleic Acids Res 2021; 49:3461-3489. [PMID: 33398329 PMCID: PMC8034618 DOI: 10.1093/nar/gkaa1239] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 11/29/2020] [Accepted: 12/15/2020] [Indexed: 02/06/2023] Open
Abstract
LARP1 is a key repressor of TOP mRNA translation. It binds the m7Gppp cap moiety and the adjacent 5'TOP motif of TOP mRNAs, thus impeding the assembly of the eIF4F complex on these transcripts. mTORC1 controls TOP mRNA translation via LARP1, but the details of the mechanism are unclear. Herein we elucidate the mechanism by which mTORC1 controls LARP1's translation repression activity. We demonstrate that mTORC1 phosphorylates LARP1 in vitro and in vivo, activities that are efficiently inhibited by rapamycin and torin1. We uncover 26 rapamycin-sensitive phospho-serine and -threonine residues on LARP1 that are distributed in 7 clusters. Our data show that phosphorylation of a cluster of residues located proximally to the m7Gppp cap-binding DM15 region is particularly sensitive to rapamycin and regulates both the RNA-binding and the translation inhibitory activities of LARP1. Our results unravel a new model of translation control in which the La module (LaMod) and DM15 region of LARP1, both of which can directly interact with TOP mRNA, are differentially regulated: the LaMod remains constitutively bound to PABP (irrespective of the activation status of mTORC1), while the C-terminal DM15 'pendular hook' engages the TOP mRNA 5'-end to repress translation, but only in conditions of mTORC1 inhibition.
Collapse
Affiliation(s)
- Jian-Jun Jia
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Roni M Lahr
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael T Solgaard
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Bruno J Moraes
- GABBA PhD Program, Abel Salazar Biomedical Sciences Institute, University of Porto, Porto, Portugal
- PrimerGen Ltd, Viseu, Portugal
| | - Roberta Pointet
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - An-Dao Yang
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Giovanna Celucci
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Tyson E Graber
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Huy-Dung Hoang
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Marius R Niklaus
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Izabella A Pena
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Anne K Hollensen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Ewan M Smith
- Cancer Research UK Beatson Institute, Glasgow, UK
| | | | - Leonie Anton
- Biozentrum, University of Basel, Basel, Switzerland
| | - Christopher Dajadian
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, McGill University, Montréal, Canada
| | - Mark Livingstone
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, McGill University, Montréal, Canada
| | - Jaclyn Hearnden
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, McGill University, Montréal, Canada
| | - Xu-Dong Wang
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yonghao Yu
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Timm Maier
- Biozentrum, University of Basel, Basel, Switzerland
| | - Christian K Damgaard
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Andrea J Berman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tommy Alain
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Bruno D Fonseca
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
- PrimerGen Ltd, Viseu, Portugal
| |
Collapse
|
21
|
Hernández-Alvarez L, Oliveira AB, Hernández-González JE, Chahine J, Pascutti PG, de Araujo AS, de Souza FP. Computational study on the allosteric mechanism of Leishmania major IF4E-1 by 4E-interacting protein-1: Unravelling the determinants of m 7GTP cap recognition. Comput Struct Biotechnol J 2021; 19:2027-2044. [PMID: 33995900 PMCID: PMC8085901 DOI: 10.1016/j.csbj.2021.03.036] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 03/25/2021] [Accepted: 03/29/2021] [Indexed: 02/07/2023] Open
Abstract
Atomistic details on perturbations induced by Lm4E-IP1 binding are described. The modulation of LmIF4E-1 affinity for the cap is confirmed by energetic analyses. Signaling paths between the allosteric and othosteric sites of LmIF4E-1 are predicted. Lm4E-IP1 binding increases the side-chain entropy of W83 and R172 of LmIF4E-1. A mechanism of dynamic allostery is proposed for the regulation mediated by Lm4E-IP1.
During their life cycle, Leishmania parasites display a fine-tuned regulation of the mRNA translation through the differential expression of isoforms of eukaryotic translation initiation factor 4E (LeishIF4Es). The interaction between allosteric modulators such as 4E-interacting proteins (4E-IPs) and LeishIF4E affects the affinity of this initiation factor for the mRNA cap. Here, several computational approaches were employed to elucidate the molecular bases of the previously-reported allosteric modulation in L. major exerted by 4E-IP1 (Lm4E-IP1) on eukaryotic translation initiation factor 4E 1 (LmIF4E-1). Molecular dynamics (MD) simulations and accurate binding free energy calculations (ΔGbind) were combined with network-based modeling of residue-residue correlations. We also describe the differences in internal motions of LmIF4E-1 apo form, cap-bound, and Lm4E-IP1-bound systems. Through community network calculations, the differences in the allosteric pathways of allosterically-inhibited and active forms of LmIF4E-1 were revealed. The ΔGbind values show significant differences between the active and inhibited systems, which are in agreement with the available experimental data. Our study thoroughly describes the dynamical perturbations of LmIF4E-1 cap-binding site triggered by Lm4E-IP1. These findings are not only essential for the understanding of a critical process of trypanosomatids’ gene expression but also for gaining insight into the allostery of eukaryotic IF4Es, which could be useful for structure-based design of drugs against this protein family.
Collapse
Affiliation(s)
- Lilian Hernández-Alvarez
- Department of Physics, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil
| | - Antonio B Oliveira
- Department of Physics, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil.,Center for Theoretical Biological Physics, Rice University, Huston, TX, United States
| | - Jorge Enrique Hernández-González
- Department of Physics, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil.,Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jorge Chahine
- Department of Physics, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil
| | - Pedro Geraldo Pascutti
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alexandre Suman de Araujo
- Department of Physics, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil
| | - Fátima Pereira de Souza
- Department of Physics, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil
| |
Collapse
|
22
|
Smith EM, Benbahouche N, Morris K, Wilczynska A, Gillen S, Schmidt T, Meijer H, Jukes-Jones R, Cain K, Jones C, Stoneley M, Waldron J, Bell C, Fonseca B, Blagden S, Willis A, Bushell M. The mTOR regulated RNA-binding protein LARP1 requires PABPC1 for guided mRNA interaction. Nucleic Acids Res 2021; 49:458-478. [PMID: 33332560 PMCID: PMC7797073 DOI: 10.1093/nar/gkaa1189] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 11/16/2020] [Accepted: 12/11/2020] [Indexed: 12/16/2022] Open
Abstract
The mammalian target of rapamycin (mTOR) is a critical regulator of cell growth, integrating multiple signalling cues and pathways. Key among the downstream activities of mTOR is the control of the protein synthesis machinery. This is achieved, in part, via the co-ordinated regulation of mRNAs that contain a terminal oligopyrimidine tract (TOP) at their 5'ends, although the mechanisms by which this occurs downstream of mTOR signalling are still unclear. We used RNA-binding protein (RBP) capture to identify changes in the protein-RNA interaction landscape following mTOR inhibition. Upon mTOR inhibition, the binding of LARP1 to a number of mRNAs, including TOP-containing mRNAs, increased. Importantly, non-TOP-containing mRNAs bound by LARP1 are in a translationally-repressed state, even under control conditions. The mRNA interactome of the LARP1-associated protein PABPC1 was found to have a high degree of overlap with that of LARP1 and our data show that PABPC1 is required for the association of LARP1 with its specific mRNA targets. Finally, we demonstrate that mRNAs, including those encoding proteins critical for cell growth and survival, are translationally repressed when bound by both LARP1 and PABPC1.
Collapse
Affiliation(s)
- Ewan M Smith
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Nour El Houda Benbahouche
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Katherine Morris
- MRC Toxicology Unit, University of Cambridge, Leicester LE1 9HN, UK
| | - Ania Wilczynska
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
- Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - Sarah Gillen
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Tobias Schmidt
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Hedda A Meijer
- Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | | | - Kelvin Cain
- MRC Toxicology Unit, University of Cambridge, Leicester LE1 9HN, UK
| | - Carolyn Jones
- MRC Toxicology Unit, University of Cambridge, Leicester LE1 9HN, UK
| | - Mark Stoneley
- MRC Toxicology Unit, University of Cambridge, Leicester LE1 9HN, UK
| | - Joseph A Waldron
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Cameron Bell
- Cancer Research UK Therapeutic Discovery Laboratories, London Bioscience Innovation Centre, 2 Royal College Street, London NW1 0NH, UK
| | | | - Sarah Blagden
- Department of Oncology, University of Oxford, Oxford, OX3 7LE, UK
| | - Anne E Willis
- MRC Toxicology Unit, University of Cambridge, Leicester LE1 9HN, UK
| | - Martin Bushell
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
- Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| |
Collapse
|
23
|
Zhao X, Zhu R, Wang Y, Qi J, Wang J, Bai L, Wang H, Wu Y, Hu H. Differentiation proliferative capacity of skeletal muscle satellite cells from Dapulian and Landrace pigs. ITALIAN JOURNAL OF ANIMAL SCIENCE 2020. [DOI: 10.1080/1828051x.2020.1769511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Xueyan Zhao
- Shandong Provincial Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Rongsheng Zhu
- Shandong Provincial Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Yanping Wang
- Shandong Provincial Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Jing Qi
- Shandong Provincial Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Jiying Wang
- Shandong Provincial Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Liya Bai
- Shandong Provincial Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Huaizhong Wang
- Shandong Provincial Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Ying Wu
- Shandong Provincial Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Hongmei Hu
- Shandong Provincial Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| |
Collapse
|
24
|
Biswas D, Dao KT, Mercer A, Cowie AM, Duffley L, El Hiani Y, Kienesberger PC, Pulinilkunnil T. Branched-chain ketoacid overload inhibits insulin action in the muscle. J Biol Chem 2020; 295:15597-15621. [PMID: 32878988 DOI: 10.1074/jbc.ra120.013121] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 08/29/2020] [Indexed: 12/18/2022] Open
Abstract
Branched-chain α-keto acids (BCKAs) are catabolites of branched-chain amino acids (BCAAs). Intracellular BCKAs are cleared by branched-chain ketoacid dehydrogenase (BCKDH), which is sensitive to inhibitory phosphorylation by BCKD kinase (BCKDK). Accumulation of BCKAs is an indicator of defective BCAA catabolism and has been correlated with glucose intolerance and cardiac dysfunction. However, it is unclear whether BCKAs directly alter insulin signaling and function in the skeletal and cardiac muscle cell. Furthermore, the role of excess fatty acids (FAs) in perturbing BCAA catabolism and BCKA availability merits investigation. By using immunoblotting and ultra-performance liquid chromatography MS/MS to analyze the hearts of fasted mice, we observed decreased BCAA-catabolizing enzyme expression and increased circulating BCKAs, but not BCAAs. In mice subjected to diet-induced obesity (DIO), we observed similar increases in circulating BCKAs with concomitant changes in BCAA-catabolizing enzyme expression only in the skeletal muscle. Effects of DIO were recapitulated by simulating lipotoxicity in skeletal muscle cells treated with saturated FA, palmitate. Exposure of muscle cells to high concentrations of BCKAs resulted in inhibition of insulin-induced AKT phosphorylation, decreased glucose uptake, and mitochondrial oxygen consumption. Altering intracellular clearance of BCKAs by genetic modulation of BCKDK and BCKDHA expression showed similar effects on AKT phosphorylation. BCKAs increased protein translation and mTORC1 activation. Pretreating cells with mTORC1 inhibitor rapamycin restored BCKA's effect on insulin-induced AKT phosphorylation. This study provides evidence for FA-mediated regulation of BCAA-catabolizing enzymes and BCKA content and highlights the biological role of BCKAs in regulating muscle insulin signaling and function.
Collapse
Affiliation(s)
- Dipsikha Biswas
- Department of Biochemistry and Molecular Biology, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada
| | - Khoi T Dao
- Department of Biochemistry and Molecular Biology, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada
| | - Angella Mercer
- Department of Biochemistry and Molecular Biology, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada
| | - Andrew M Cowie
- Department of Biochemistry and Molecular Biology, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada
| | - Luke Duffley
- Department of Biochemistry and Molecular Biology, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada
| | - Yassine El Hiani
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Petra C Kienesberger
- Department of Biochemistry and Molecular Biology, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada
| | - Thomas Pulinilkunnil
- Department of Biochemistry and Molecular Biology, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada.
| |
Collapse
|
25
|
Kim JK, Cho J, Kim SH, Kang HC, Kim DS, Kim VN, Lee JH. Brain somatic mutations in MTOR reveal translational dysregulations underlying intractable focal epilepsy. J Clin Invest 2020; 129:4207-4223. [PMID: 31483294 DOI: 10.1172/jci127032] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 07/03/2019] [Indexed: 12/15/2022] Open
Abstract
Brain somatic mutations confer genomic diversity in the human brain and cause neurodevelopmental disorders. Recently, brain somatic activating mutations in MTOR have been identified as a major etiology of intractable epilepsy in patients with cortical malformations. However, the molecular genetic mechanism of how brain somatic mutations in MTOR cause intractable epilepsy has remained elusive. In this study, translational profiling of intractable epilepsy mouse models with brain somatic mutations and genome-edited cells revealed a novel translational dysregulation mechanism and mTOR activation-sensitive targets mediated by human MTOR mutations that lead to intractable epilepsy with cortical malformation. These mTOR targets were found to be regulated by novel mTOR-responsive 5'-UTR motifs, distinct from known mTOR inhibition-sensitive targets regulated by 5' terminal oligopyrimidine motifs. Novel mTOR target genes were validated in patient brain tissues, and the mTOR downstream effector eIF4E was identified as a new therapeutic target in intractable epilepsy via pharmacological or genetic inhibition. We show that metformin, an FDA-approved eIF4E inhibitor, suppresses intractable epilepsy. Altogether, the present study describes translational dysregulation resulting from brain somatic mutations in MTOR, as well as the pathogenesis and potential therapeutic targets of intractable epilepsy.
Collapse
Affiliation(s)
- Jang Keun Kim
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Jun Cho
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.,Center for RNA Research, Institute for Basic Science, Seoul, Republic of Korea
| | - Se Hoon Kim
- Department of Pathology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hoon-Chul Kang
- Division of Pediatric Neurology, Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital, Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Dong-Seok Kim
- Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea.,Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - V Narry Kim
- Center for RNA Research, Institute for Basic Science, Seoul, Republic of Korea.,Department of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Jeong Ho Lee
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,Graduate School of Medical Science and Engineering, KAIST, Daejeon, Republic of Korea
| |
Collapse
|
26
|
Translational profiling of macrophages infected with Leishmania donovani identifies mTOR- and eIF4A-sensitive immune-related transcripts. PLoS Pathog 2020; 16:e1008291. [PMID: 32479529 PMCID: PMC7310862 DOI: 10.1371/journal.ppat.1008291] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 06/23/2020] [Accepted: 05/13/2020] [Indexed: 12/28/2022] Open
Abstract
The protozoan parasite Leishmania donovani (L. donovani) causes visceral leishmaniasis, a chronic infection which is fatal when untreated. Herein, we investigated whether in addition to altering transcription, L. donovani modulates host mRNA translation to establish a successful infection. Polysome-profiling revealed that one third of protein-coding mRNAs expressed in primary mouse macrophages are differentially translated upon infection with L. donovani promastigotes or amastigotes. Gene ontology analysis identified key biological processes enriched for translationally regulated mRNAs and were predicted to be either activated (e.g. chromatin remodeling and RNA metabolism) or inhibited (e.g. intracellular trafficking and antigen presentation) upon infection. Mechanistic in silico and biochemical analyses showed selective activation mTOR- and eIF4A-dependent mRNA translation, including transcripts encoding central regulators of mRNA turnover and inflammation (i.e. PABPC1, EIF2AK2, and TGF-β). L. donovani survival within macrophages was favored under mTOR inhibition but was dampened by pharmacological blockade of eIF4A. Overall, this study uncovers a vast yet selective reprogramming of the host cell translational landscape early during L. donovani infection, and suggests that some of these changes are involved in host defense mechanisms while others are part of parasite-driven survival strategies. Further in vitro and in vivo investigation will shed light on the contribution of mTOR- and eIF4A-dependent translational programs to the outcome of visceral leishmaniasis.
Collapse
|
27
|
Méndez-Gómez M, Castro-Mercado E, Peña-Uribe CA, Reyes-de la Cruz H, López-Bucio J, García-Pineda E. TARGET OF RAPAMYCIN signaling plays a role in Arabidopsis growth promotion by Azospirillum brasilense Sp245. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 293:110416. [PMID: 32081264 DOI: 10.1016/j.plantsci.2020.110416] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 12/16/2019] [Accepted: 12/19/2019] [Indexed: 06/10/2023]
Abstract
Azospirillum brasilense colonizes plant roots and improves productivity, but the molecular mechanisms behind its phytostimulation properties remain mostly unknown. Here, we uncover an important role of TARGET OF RAPAMYCIN (TOR) signaling on the response of Arabidopsis thaliana to A. brasilense Sp245. The effect of the bacterium on TOR expression was analyzed in the transgenic line TOR/tor-1, which carries a translational fusion with the GUS reporter protein, and the activity of TOR was assayed thought the phosphorylation of its downstream signaling target S6K protein. Besides, the role of TOR on plant growth in inoculated plants was assessed using the ATP-competitive inhibitor AZD-8055. A decrease in growth of the primary root correlates with an improved branching and absorptive capacity via lateral root and root hair proliferation 6 days after transplant to different concentrations of the bacterium (103 or 105 CFU/mL). Bacterization increased the expression of TOR in shoot and root apexes and promoted phosphorylation of S6K 3 days after transplant. The TOR inhibitor AZD-8055 (1 μM) inhibited plant growth and cell division in root meristems and in lateral root primordia, interfering with the phytostimulation by A. brasilense. In addition, the role of auxin produced by the bacterium to stimulate TOR expression was explored. Noteworthy, the A. brasilense mutant FAJ009, impaired in auxin production, was unable to elicit TOR signaling to the level observed for the wild-type strain, showing the importance of this phyhormone to stimulate TOR signaling. Together, our findings establish an important role of TOR signaling for the probiotic traits elicited by A. brasilense in A. thaliana.
Collapse
Affiliation(s)
- Manuel Méndez-Gómez
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. A1´, Morelia, Michoacán CP 58040, Mexico
| | - Elda Castro-Mercado
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. A1´, Morelia, Michoacán CP 58040, Mexico
| | - César Arturo Peña-Uribe
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. A1´, Morelia, Michoacán CP 58040, Mexico
| | - Homero Reyes-de la Cruz
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. A1´, Morelia, Michoacán CP 58040, Mexico
| | - José López-Bucio
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. A1´, Morelia, Michoacán CP 58040, Mexico
| | - Ernesto García-Pineda
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. A1´, Morelia, Michoacán CP 58040, Mexico.
| |
Collapse
|
28
|
Zhou C, Liu C, Liu W, Chen W, Yin Y, Li CW, Hsu JL, Sun J, Zhou Q, Li H, Hu B, Fu P, Atyah M, Ma Q, Xu Y, Dong Q, Hung MC, Ren N. SLFN11 inhibits hepatocellular carcinoma tumorigenesis and metastasis by targeting RPS4X via mTOR pathway. Theranostics 2020; 10:4627-4643. [PMID: 32292519 PMCID: PMC7150495 DOI: 10.7150/thno.42869] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 03/05/2020] [Indexed: 12/19/2022] Open
Abstract
Hepatocellular carcinoma (HCC) remains one of the most refractory malignancies worldwide. Schlafen family member 11 (SLFN11) has been reported to play an important role in inhibiting the production of human immunodeficiency virus 1 (HIV-1). However, whether SLFN11 also inhibits hepatitis B virus (HBV), and affects HBV-induced HCC remain to be systematically investigated. Methods: qRT-PCR, western blot and immunohistochemical (IHC) staining were conducted to investigate the potential role and prognostic value of SLFN11 in HCC. Then SLFN11 was stably overexpressed or knocked down in HCC cell lines. To further explore the potential biological function of SLFN11 in HCC, cell counting kit-8 (CCK-8) assays, colony formation assays, wound healing assays and transwell cell migration and invasion assays were performed in vitro. Meanwhile, HCC subcutaneous xenograft tumor models were established for in vivo assays. Subsequently, immunoprecipitation (IP) and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analyses were applied to understand the molecular mechanisms of SLFN11 in HCC. Co-IP, immunofluorescence and IHC staining were used to analyze the relationship between ribosomal protein S4 X-linked (RPS4X) and SLFN11. Finally, the therapeutic potential of SLFN11 with mTOR pathway inhibitor INK128 on inhibiting HCC growth and metastasis was evaluated in vitro and in vivo orthotopic xenograft mouse models. Results: We demonstrate that SLFN11 expression is decreased in HCC, which is associated with shorter overall survival and higher recurrence rates in patients. In addition, we show that low SLFN11 expression is associated with aggressive clinicopathologic characteristics. Moreover, overexpression of SLFN11 inhibits HCC cell proliferation, migration, and invasion, facilitates apoptosis in vitro, and impedes HCC growth and metastasis in vivo, all of which are attenuated by SLFN11 knockdown. Mechanistically, SLFN11 physically associates with RPS4X and blocks the mTOR signaling pathway. In orthotopic mouse models, overexpression of SLFN11 or inhibition of mTOR pathway inhibitor by INK128 reverses HCC progression and metastasis. Conclusions: SLFN11 may serve as a powerful prognostic biomarker and putative tumor suppressor by suppressing the mTOR signaling pathway via RPS4X in HCC. Our study may therefore offer a novel therapeutic strategy for treating HCC patients with the mTOR pathway inhibitor INK128.
Collapse
Affiliation(s)
- Chenhao Zhou
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Chunxiao Liu
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Wenjie Liu
- Biomedical Research Centre, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Wanyong Chen
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
- Institute of Fudan Minhang Academic Health System, and Key Laboratory of Whole-period Monitoring and Precise Intervention of Digestive Cancer (SMHC), Minhang Hospital & AHS, Fudan University, Shanghai, China
| | - Yirui Yin
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
| | - Chia-Wei Li
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jennifer L. Hsu
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jialei Sun
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
| | - Qiang Zhou
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
| | - Hui Li
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Bo Hu
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
| | - Peiyao Fu
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
| | - Manar Atyah
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
| | - Qianni Ma
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
| | - Yang Xu
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
| | - Qiongzhu Dong
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Institute of Fudan Minhang Academic Health System, and Key Laboratory of Whole-period Monitoring and Precise Intervention of Digestive Cancer (SMHC), Minhang Hospital & AHS, Fudan University, Shanghai, China
- Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Mien-Chie Hung
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Graduate Institute of Biomedical Sciences and Center for Molecular Medicine, China Medical University, Taichung, Taiwan
| | - Ning Ren
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, and Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Fudan University, Shanghai, China
- Institute of Fudan Minhang Academic Health System, and Key Laboratory of Whole-period Monitoring and Precise Intervention of Digestive Cancer (SMHC), Minhang Hospital & AHS, Fudan University, Shanghai, China
| |
Collapse
|
29
|
Smekalova EM, Gerashchenko MV, O'Connor PBF, Whittaker CA, Kauffman KJ, Fefilova AS, Zatsepin TS, Bogorad RL, Baranov PV, Langer R, Gladyshev VN, Anderson DG, Koteliansky V. In Vivo RNAi-Mediated eIF3m Knockdown Affects Ribosome Biogenesis and Transcription but Has Limited Impact on mRNA-Specific Translation. MOLECULAR THERAPY. NUCLEIC ACIDS 2020; 19:252-266. [PMID: 31855834 PMCID: PMC6926209 DOI: 10.1016/j.omtn.2019.11.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 10/20/2019] [Accepted: 11/05/2019] [Indexed: 12/19/2022]
Abstract
Translation is an essential biological process, and dysregulation is associated with a range of diseases including ribosomopathies, diabetes, and cancer. Here, we examine translation dysregulation in vivo using RNAi to knock down the m-subunit of the translation initiation factor eIF3 in the mouse liver. Transcriptome sequencing, ribosome profiling, whole proteome, and phosphoproteome analyses show that eIF3m deficiency leads to the transcriptional response and changes in cellular translation that yield few detectable differences in the translation of particular mRNAs. The transcriptional response fell into two main categories: ribosome biogenesis (increased transcription of ribosomal proteins) and cell metabolism (alterations in lipid, amino acid, nucleic acid, and drug metabolism). Analysis of ribosome biogenesis reveals inhibition of rRNA processing, highlighting decoupling of rRNA synthesis and ribosomal protein gene transcription in response to eIF3m knockdown. Interestingly, a similar reduction in eIF3m protein levels is associated with induction of the mTOR pathway in vitro but not in vivo. Overall, this work highlights the utility of a RNAi-based in vivo approach for studying the regulation of mammalian translation in vivo.
Collapse
Affiliation(s)
- Elena M Smekalova
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Maxim V Gerashchenko
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Patrick B F O'Connor
- School of Biochemistry and Cell Biology, University College Cork, Cork T12 YN60, Ireland
| | - Charles A Whittaker
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Kevin J Kauffman
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Anna S Fefilova
- Skolkovo Institute of Science and Technology, Skolkovo, Moscow, 121205, Russia
| | - Timofei S Zatsepin
- Skolkovo Institute of Science and Technology, Skolkovo, Moscow, 121205, Russia; Department of Chemistry and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
| | - Roman L Bogorad
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Pavel V Baranov
- School of Biochemistry and Cell Biology, University College Cork, Cork T12 YN60, Ireland; Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, RAS, Moscow 117997, Russia
| | - Robert Langer
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, USA; Institute of Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Vadim N Gladyshev
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Daniel G Anderson
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, USA; Institute of Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Victor Koteliansky
- Skolkovo Institute of Science and Technology, Skolkovo, Moscow, 121205, Russia.
| |
Collapse
|
30
|
Interplay between RNA-binding protein HuR and Nox4 as a novel therapeutic target in diabetic kidney disease. Mol Metab 2020; 36:100968. [PMID: 32240965 PMCID: PMC7115155 DOI: 10.1016/j.molmet.2020.02.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/14/2020] [Accepted: 02/22/2020] [Indexed: 12/28/2022] Open
Abstract
Objective Glomerular injury is a prominent pathological feature of diabetic kidney disease (DKD). Constitutively active NADPH oxidase 4 (Nox4) is a major source of reactive oxygen species that mediates hyperglycemia-induced mesangial cell (MC) fibrotic injury. However, the mechanism that Nox4 utilizes to achieve its biological outcome remains elusive, and the signaling pathways that regulate this isoform oxidase are not well understood. Here, our goal is to study the detailed mechanism by which NAPDH oxidase 4 (Nox4) is post-transcriptionally regulated in MC during diabetic pathology. Methods We studied the protein expression of HuR, Nox4 and matrix proteins by western blotting, while we assessed the mRNA stability of Nox4 by RT-PCR and polysomal assay, examined in vitro cultured glomerular mesangial cells treated by high glucose (HG) and diabetic animal induced by STZ. The binding assay between HuR and the Nox4 promoter was done by immuno-precipiating with HuR antibody and detecting the presence of Nox4 mRNA, or by pull-down by using biotinlyated labeled Nox4 promoter RNA and detecting the presence of the HuR protein. The binding was also confirmed in MCs where Nox4 promoter-containing luciferage constructs were transfected. ROS levels were measured with DHE/DCF dyes in cells, or lucigenin chemiluminescence for Nox enzymatic levels, or HPLC assay for superoxide. HuR protein was inhibited by antisense oligo that utilized osmotic pumps for continuous delivery in animal models. The H1bAc1 ratio was measured by an ELISA kit for mice. Results We demonstrate that in MCs, high glucose (HG) elicits a rapid upregulation of Nox4 protein via translational mechanisms. Nox4 mRNA 3′ untranslated region (3′-UTR) contains numerous AU-rich elements (AREs) that are potential binding sites for the RNA-binding protein human antigen R (HuR). We show that HG promotes HuR activation/expression and that HuR is required for HG-induced Nox4 protein expression/mRNA translation, ROS generation, and subsequent MC fibrotic injury. Through a series of invitro RNA-binding assays, we demonstrate that HuR acts via binding to AREs in Nox4 3′-UTR in response to HG. The invivo relevance of these observations is confirmed by the findings that increased Nox4 is accompanied by the binding of HuR to Nox4 mRNA in kidneys from type 1 diabetic animals, and further suppressing HuR expression showed a reno-protective role in a type 1 diabetic mouse model via reducing MC injury, along with the improvement of hyperglycemia and renal function. Conclusions We established for the first time that HuR-mediated translational regulation of Nox4 contributes to the pathogenesis of fibrosis of the glomerular microvascular bed. Thus therapeutic interventions affecting the interplay between Nox4 and HuR could be exploited as valuable tools in designing treatments for DKD. Increased HuR protein activation/expression responding to HG treatment and in diabetic animals. HuR binds to 3′UTR of Nox4 and promotes its translation during HG treatment. An inhibitor for HuR could be a potential treatment for diabetic kidney disease.
Collapse
|
31
|
Overexpression of p-Akt, p-mTOR and p-eIF4E proteins associates with metastasis and unfavorable prognosis in non-small cell lung cancer. PLoS One 2020; 15:e0227768. [PMID: 32023262 PMCID: PMC7001968 DOI: 10.1371/journal.pone.0227768] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 12/28/2019] [Indexed: 12/24/2022] Open
Abstract
The Akt (protein kinase B)/mammalian target of rapamycin (mTOR) pathway, which is dysregulated in various cancers, controls the assembly of eukaryotic translation initiation factor 4F (eIF4E) complex. However, whether aberrant expression of phosphorylated Akt (p-Akt), phosphorylated mTOR (p-mTOR) and phosphorylated eIF4E (p-eIF4E) is associated with clinicopathological characteristics in surgically resected non-small cell lung cancer (NSCLC) has been rarely reported. Here, we investigated expression of p-Akt, p-mTOR and p-eIF4E proteins in NSCLC by immunohistochemistry and evaluated their correlation with clinicopathological characteristics and prognostic significance. The results showed that the positive percentage of p-Akt, p-mTOR and p-eIF4E was higher in NSCLC. Additionally, p-mTOR and p-eIF4E was dramatically higher in lung adenocarcinoma (both P<0.05). Most importantly, NSCLC patients with lymph node metastasis had significantly elevated expression of p-Akt, p-mTOR and p-eIF4E (all P<0.05). Positive expression of p-Akt, and any positive expression of p-Akt, p-mTOR and p-eIF4E proteins were positively correlated with clinical stages (both P<0.05). Spearman’s rank correlation test revealed that expression of p-Akt was correlated with p-eIF4E and p-mTOR (r = 0.107, P = 0.047; r = 0.287, P<0.001, respectively). Also, p-eIF4E had positive correlation with p-mTOR (r = 0.265, P<0.001). Furthermore, NSCLC patients with increased expression of p-Akt, p-mTOR and p-eIF4E, and any positive expression of above three proteins had lower overall survival rates (all P<0.05). Multivariate Cox regression analysis further indicated thatp-eIF4E was an independent prognostic factor for NSCLC patients (P = 0.046). Taken together, overexpression of p-Akt, p-mTOR and p-eIF4E proteins is associated with metastasis and poor prognosis of NSCLC patients after surgical resection, and positive expression of p-eIF4E protein may act as an independent unfavorable prognostic biomarker for overall survival of NSCLC patients.
Collapse
|
32
|
Cassidy KC, Lahr RM, Kaminsky JC, Mack S, Fonseca BD, Das SR, Berman AJ, Durrant JD. Capturing the Mechanism Underlying TOP mRNA Binding to LARP1. Structure 2019; 27:1771-1781.e5. [PMID: 31676287 PMCID: PMC7269035 DOI: 10.1016/j.str.2019.10.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 08/06/2019] [Accepted: 10/10/2019] [Indexed: 12/20/2022]
Abstract
The RNA-binding protein La-related protein 1 (LARP1) plays a central role in ribosome biosynthesis. Its C-terminal DM15 region binds the 7-methylguanosine (m7G) cap and 5' terminal oligopyrimidine (TOP) motif characteristic of transcripts encoding ribosomal proteins and translation factors. Under the control of mammalian target of rapamycin complex 1 (mTORC1), LARP1 regulates translation of these transcripts. Characterizing the dynamics of DM15-TOP recognition is essential to understanding this fundamental biological process. We use molecular dynamics simulations, biophysical assays, and X-ray crystallography to reveal the mechanism of DM15 binding to TOP transcripts. Residues C-terminal to the m7G-binding site play important roles in cap recognition. Furthermore, we show that the unusually static pocket that recognizes the +1 cytosine characteristic of TOP transcripts drives binding specificity. Finally, we demonstrate that the DM15 pockets involved in TOP-specific m7GpppC-motif recognition are likely druggable. Collectively, these studies suggest unique opportunities for further pharmacological development.
Collapse
Affiliation(s)
- Kevin C Cassidy
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15260, USA
| | - Roni M Lahr
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15260, USA
| | - Jesse C Kaminsky
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15260, USA
| | - Stephanie Mack
- Department of Chemistry and Center for Nucleic Acids Science & Technology, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, USA
| | - Bruno D Fonseca
- Children's Hospital of Eastern Ontario Research Institute, 401 Smyth Road, Ottawa, K1H 8L1 ON, Canada
| | - Subha R Das
- Department of Chemistry and Center for Nucleic Acids Science & Technology, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, USA
| | - Andrea J Berman
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15260, USA.
| | - Jacob D Durrant
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15260, USA.
| |
Collapse
|
33
|
Abstract
Individual cell types have characteristic sizes, suggesting that size sensing mechanisms may coordinate transcription, translation, and metabolism with cell growth rates. Two types of size-sensing mechanisms have been proposed: spatial sensing of the location or dimensions of a signal, subcellular structure or organelle; or titration-based sensing of the intracellular concentrations of key regulators. Here we propose that size sensing in animal cells combines both titration and spatial sensing elements in a dynamic mechanism whereby microtubule motor-dependent localization of RNA encoding importin β1 and mTOR, coupled with regulated local protein synthesis, enable cytoskeleton length sensing for cell growth regulation.
Collapse
Affiliation(s)
- Ida Rishal
- Department of Biomolecular Sciences, Weizmann Institute of Science, 76100, Rehovot, Israel
| | - Mike Fainzilber
- Department of Biomolecular Sciences, Weizmann Institute of Science, 76100, Rehovot, Israel.
| |
Collapse
|
34
|
Margalha L, Confraria A, Baena-González E. SnRK1 and TOR: modulating growth-defense trade-offs in plant stress responses. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2261-2274. [PMID: 30793201 DOI: 10.1093/jxb/erz066] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 02/07/2019] [Indexed: 05/11/2023]
Abstract
The evolutionarily conserved protein kinase complexes SnRK1 and TOR are central metabolic regulators essential for plant growth, development, and stress responses. They are activated by opposite signals, and the outcome of their activation is, in global terms, antagonistic. Similarly to their yeast and animal counterparts, SnRK1 is activated by the energy deficit often associated with stress to restore homeostasis, while TOR is activated in nutrient-rich conditions to promote growth. Recent evidence suggests that SnRK1 represses TOR in plants, revealing evolutionary conservation also in their crosstalk. Given their importance for integrating environmental information into growth and developmental programs, these signaling pathways hold great promise for reducing the growth penalties caused by stress. Here we review the literature connecting SnRK1 and TOR to plant stress responses. Although SnRK1 and TOR emerge mostly as positive regulators of defense and growth, respectively, the outcome of their activities in plant growth and performance is not always straightforward. Manipulation of both pathways under similar experimental setups, as well as further biochemical and genetic analyses of their molecular and functional interaction, is essential to fully understand the mechanisms through which these two metabolic pathways contribute to stress responses, growth, and development.
Collapse
Affiliation(s)
- Leonor Margalha
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande,Oeiras, Portugal
| | - Ana Confraria
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande,Oeiras, Portugal
| | | |
Collapse
|
35
|
Mondaca-Ruff D, Riquelme JA, Quiroga C, Norambuena-Soto I, Sanhueza-Olivares F, Villar-Fincheira P, Hernández-Díaz T, Cancino-Arenas N, San Martin A, García L, Lavandero S, Chiong M. Angiotensin II-Regulated Autophagy Is Required for Vascular Smooth Muscle Cell Hypertrophy. Front Pharmacol 2019; 9:1553. [PMID: 30804791 PMCID: PMC6371839 DOI: 10.3389/fphar.2018.01553] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 12/20/2018] [Indexed: 12/14/2022] Open
Abstract
Hypertension is a disease associated to increased plasma levels of angiotensin II (Ang II). Ang II can regulate proliferation, migration, ROS production and hypertrophy of vascular smooth muscle cells (VSMCs). However, the mechanisms by which Ang II can affect VSMCs remain to be fully elucidated. In this context, autophagy, a process involved in self-digestion of proteins and organelles, has been described to regulate vascular remodeling. Therefore, we sought to investigate if Ang II regulates VSMC hypertrophy through an autophagy-dependent mechanism. To test this, we stimulated A7r5 cell line and primary rat aortic smooth muscle cells with Ang II 100 nM and measured autophagic markers at 24 h by Western blot. Autophagosomes were quantified by visualizing fluorescently labeled LC3 using confocal microscopy. The results showed that treatment with Ang II increases Beclin-1, Vps34, Atg-12-Atg5, Atg4 and Atg7 protein levels, Beclin-1 phosphorylation, as well as the number of autophagic vesicles, suggesting that this peptide induces autophagy by activating phagophore initiation and elongation. These findings were confirmed by the assessment of autophagic flux by co-administering Ang II together with chloroquine (30 μM). Pharmacological antagonism of the angiotensin type 1 receptor (AT1R) with losartan and RhoA/Rho Kinase inhibition prevented Ang II-induced autophagy. Moreover, Ang II-induced A7r5 hypertrophy, evaluated by α-SMA expression and cell size, was prevented upon autophagy inhibition. Taking together, our results suggest that the induction of autophagy by an AT1R/RhoA/Rho Kinase-dependent mechanism contributes to Ang II-induced hypertrophy in VSMC.
Collapse
Affiliation(s)
- David Mondaca-Ruff
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Jaime A Riquelme
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Clara Quiroga
- Advanced Center for Chronic Diseases (ACCDiS), División de Enfermedades Cardiovasculares, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Ignacio Norambuena-Soto
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Fernanda Sanhueza-Olivares
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Paulina Villar-Fincheira
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Tomás Hernández-Díaz
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Nicole Cancino-Arenas
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Alejandra San Martin
- Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA, United States
| | - Lorena García
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Sergio Lavandero
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.,Department of Internal Medicine (Cardiology Division), University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Mario Chiong
- Advanced Center for Chronic Diseases (ACCDiS), Centro de Estudios en Ejercicio, Metabolismo y Cáncer (CEMC), Departamento Bioquímica y Biología Molecular, Facultad Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| |
Collapse
|
36
|
TOR and RPS6 transmit light signals to enhance protein translation in deetiolating Arabidopsis seedlings. Proc Natl Acad Sci U S A 2018; 115:12823-12828. [PMID: 30482859 PMCID: PMC6294885 DOI: 10.1073/pnas.1809526115] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Light enhances the translation efficiency of thousands of mRNAs during photomorphogenic development in Arabidopsis, but the underlying molecular mechanism remains elusive. Here we show that light activates the auxin-target of rapamycin (TOR)-ribosome protein S6 (RPS6) pathway to enhance translation in deetiolating Arabidopsis. We discovered that CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) represses TOR activity in dark-grown seedlings. The perception of far-red and blue light by photoreceptors inactivates COP1, which leads to the derepression of the auxin-TOR-RPS6 pathway and enhanced de novo protein synthesis. Our study revealed a light-triggered signaling pathway for translational regulation. This sophisticated regulation also functions to ensure that young seedlings have strict skotomorphogenic development in the dark and a timely switch to photomorphogenic development. Deetiolation is an essential developmental process transforming young plant seedlings into the vegetative phase with photosynthetic activities. Light signals initiate this important developmental process by triggering massive reprogramming of the transcriptome and translatome. Compared with the wealth of knowledge of transcriptional regulation, the molecular mechanism underlying this light-triggered translational enhancement remains unclear. Here we show that light-enhanced translation is orchestrated by a light perception and signaling pathway composed of photoreceptors, CONSTITUTIVE PHOTOMORPHOGENESIS 1 (COP1), the phytohormone auxin, target of rapamycin (TOR), and ribosomal protein S6 (RPS6). In deetiolating Arabidopsis seedlings, photoreceptors, including phytochrome A and cryptochromes, perceive far-red and blue light to inactivate the negative regulator COP1, which leads to activation of the auxin pathway for TOR-dependent phosphorylation of RPS6. Arabidopsis mutants defective in TOR, RPS6A, or RPS6B exhibited delayed cotyledon opening, a characteristic of the deetiolating process to ensure timely vegetative development of a young seedling. This study provides a mechanistic view of light-triggered translational enhancement in deetiolating Arabidopsis.
Collapse
|
37
|
Fonseca BD, Lahr RM, Damgaard CK, Alain T, Berman AJ. LARP1 on TOP of ribosome production. WILEY INTERDISCIPLINARY REVIEWS. RNA 2018; 9:e1480. [PMID: 29722158 PMCID: PMC6214789 DOI: 10.1002/wrna.1480] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 03/06/2018] [Accepted: 03/07/2018] [Indexed: 12/27/2022]
Abstract
The ribosome is an essential unit of all living organisms that commands protein synthesis, ultimately fuelling cell growth (accumulation of cell mass) and cell proliferation (increase in cell number). The eukaryotic ribosome consists of 4 ribosomal RNAs (rRNAs) and 80 ribosomal proteins (RPs). Despite its fundamental role in every living organism, our present understanding of how higher eukaryotes produce the various ribosome components is incomplete. Uncovering the mechanisms utilized by human cells to generate functional ribosomes will likely have far-reaching implications in human disease. Recent biochemical and structural studies revealed La-related protein 1 (LARP1) as a key new player in RP production. LARP1 is an RNA-binding protein that belongs to the LARP superfamily; it controls the translation and stability of the mRNAs that encode RPs and translation factors, which are characterized by a 5' terminal oligopyrimidine (5'TOP) motif and are thus known as TOP mRNAs. The activity of LARP1 is regulated by the mammalian target of rapamycin complex 1 (mTORC1): a eukaryotic protein kinase complex that integrates nutrient sensing with mRNA translation, particularly that of TOP mRNAs. In this review, we provide an overview of the role of LARP1 in the control of ribosome production in multicellular eukaryotes. This article is categorized under: Translation > Translation Regulation RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Processing > Capping and 5' End Modifications.
Collapse
Affiliation(s)
| | | | | | - Tommy Alain
- Children’s Hospital of Eastern Ontario, Ottawa, ON, Canada
| | | |
Collapse
|
38
|
Zakaria C, Sean P, Hoang HD, Leroux LP, Watson M, Workenhe ST, Hearnden J, Pearl D, Truong VT, Robichaud N, Yanagiya A, Tahmasebi S, Jafarnejad SM, Jia JJ, Pelin A, Diallo JS, Le Boeuf F, Bell JC, Mossman KL, Graber TE, Jaramillo M, Sonenberg N, Alain T. Active-site mTOR inhibitors augment HSV1-dICP0 infection in cancer cells via dysregulated eIF4E/4E-BP axis. PLoS Pathog 2018; 14:e1007264. [PMID: 30138450 PMCID: PMC6124814 DOI: 10.1371/journal.ppat.1007264] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 09/05/2018] [Accepted: 08/07/2018] [Indexed: 12/21/2022] Open
Abstract
Herpes Simplex Virus 1 (HSV1) is amongst the most clinically advanced oncolytic virus platforms. However, efficient and sustained viral replication within tumours is limiting. Rapamycin can stimulate HSV1 replication in cancer cells, but active-site dual mTORC1 and mTORC2 (mammalian target of rapamycin complex 1 and 2) inhibitors (asTORi) were shown to suppress the virus in normal cells. Surprisingly, using the infected cell protein 0 (ICP0)-deleted HSV1 (HSV1-dICP0), we found that asTORi markedly augment infection in cancer cells and a mouse mammary cancer xenograft. Mechanistically, asTORi repressed mRNA translation in normal cells, resulting in defective antiviral response but also inhibition of HSV1-dICP0 replication. asTORi also reduced antiviral response in cancer cells, however in contrast to normal cells, transformed cells and cells transduced to elevate the expression of eukaryotic initiation factor 4E (eIF4E) or to silence the repressors eIF4E binding proteins (4E-BPs), selectively maintained HSV1-dICP0 protein synthesis during asTORi treatment, ultimately supporting increased viral replication. Our data show that altered eIF4E/4E-BPs expression can act to promote HSV1-dICP0 infection under prolonged mTOR inhibition. Thus, pharmacoviral combination of asTORi and HSV1 can target cancer cells displaying dysregulated eIF4E/4E-BPs axis. Dysregulated mRNA translation occurs frequently in tumours due to elevated eIF4E expression or a hyperactive mTOR complex 1 (mTORC1) signaling pathway that results in the inactivation of the eIF4E binding proteins (4E-BPs). Targeting the mTORC1/4E-BPs/eIF4E axis is a promising strategy in cancer therapies and for preventing resistance to treatment. Enhanced mTORC1 activity also drives innate immune responses by modulating protein expression of antiviral genes. It was previously shown that the mTORC1 inhibitor rapamycin limits antiviral responses and promotes replication of oncolytic viruses within tumour tissues. Active-site dual mTORC1 and mTORC2 inhibitors (asTORi) have been developed for superior mTOR inhibition and anti-cancer potency but have not been studied in the context of oncolytic viral infection. We show here that prolonged treatment with asTORi strongly augments infection of HSV1-dICP0 in cancer cells, but not in normal cells, an effect modulated via eIF4E/4E-BP expression. Thus, cancer cells with dysregulated translation could be amenable to the pharmacoviral combination of HSV1 and asTORi treatment.
Collapse
Affiliation(s)
- Chadi Zakaria
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Canada
| | - Polen Sean
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Canada
| | - Huy-Dung Hoang
- Children's Hospital of Eastern Ontario Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | | | - Margaret Watson
- Children's Hospital of Eastern Ontario Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Samuel Tekeste Workenhe
- Department of Pathology and Molecular Medicine, MG DeGroote Institute for Infectious Disease, McMaster University, Hamilton, Ontario, Canada
| | - Jaclyn Hearnden
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Canada
| | - Dana Pearl
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Canada
| | - Vinh Tai Truong
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Canada
| | - Nathaniel Robichaud
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Canada
| | - Akiko Yanagiya
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Canada
| | - Soroush Tahmasebi
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Canada
| | | | - Jian-Jun Jia
- Children's Hospital of Eastern Ontario Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Adrian Pelin
- Center for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Jean-Simon Diallo
- Center for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Fabrice Le Boeuf
- Center for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - John Cameron Bell
- Center for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Karen Louise Mossman
- Department of Pathology and Molecular Medicine, MG DeGroote Institute for Infectious Disease, McMaster University, Hamilton, Ontario, Canada
| | - Tyson Ernst Graber
- Children's Hospital of Eastern Ontario Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Maritza Jaramillo
- INRS Institut Armand-Frappier Research Centre, Laval, Quebec, Canada
| | - Nahum Sonenberg
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Canada
- * E-mail: (NS); (TA)
| | - Tommy Alain
- Children's Hospital of Eastern Ontario Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
- * E-mail: (NS); (TA)
| |
Collapse
|
39
|
Walters HE, Cox LS. mTORC Inhibitors as Broad-Spectrum Therapeutics for Age-Related Diseases. Int J Mol Sci 2018; 19:E2325. [PMID: 30096787 PMCID: PMC6121351 DOI: 10.3390/ijms19082325] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/22/2018] [Accepted: 07/30/2018] [Indexed: 02/06/2023] Open
Abstract
Chronological age represents the greatest risk factor for many life-threatening diseases, including neurodegeneration, cancer, and cardiovascular disease; ageing also increases susceptibility to infectious disease. Current efforts to tackle individual diseases may have little impact on the overall healthspan of older individuals, who would still be vulnerable to other age-related pathologies. However, recent progress in ageing research has highlighted the accumulation of senescent cells with chronological age as a probable underlying cause of pathological ageing. Cellular senescence is an essentially irreversible proliferation arrest mechanism that has important roles in development, wound healing, and preventing cancer, but it may limit tissue function and cause widespread inflammation with age. The serine/threonine kinase mTOR (mechanistic target of rapamycin) is a regulatory nexus that is heavily implicated in both ageing and senescence. Excitingly, a growing body of research has highlighted rapamycin and other mTOR inhibitors as promising treatments for a broad spectrum of age-related pathologies, including neurodegeneration, cancer, immunosenescence, osteoporosis, rheumatoid arthritis, age-related blindness, diabetic nephropathy, muscular dystrophy, and cardiovascular disease. In this review, we assess the use of mTOR inhibitors to treat age-related pathologies, discuss possible molecular mechanisms of action where evidence is available, and consider strategies to minimize undesirable side effects. We also emphasize the urgent need for reliable, non-invasive biomarkers of senescence and biological ageing to better monitor the efficacy of any healthy ageing therapy.
Collapse
Affiliation(s)
- Hannah E Walters
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
| | - Lynne S Cox
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
| |
Collapse
|
40
|
Schneider-Poetsch T, Yoshida M. Along the Central Dogma-Controlling Gene Expression with Small Molecules. Annu Rev Biochem 2018; 87:391-420. [PMID: 29727582 DOI: 10.1146/annurev-biochem-060614-033923] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The central dogma of molecular biology, that DNA is transcribed into RNA and RNA translated into protein, was coined in the early days of modern biology. Back in the 1950s and 1960s, bacterial genetics first opened the way toward understanding life as the genetically encoded interaction of macromolecules. As molecular biology progressed and our knowledge of gene control deepened, it became increasingly clear that expression relied on many more levels of regulation. In the process of dissecting mechanisms of gene expression, specific small-molecule inhibitors played an important role and became valuable tools of investigation. Small molecules offer significant advantages over genetic tools, as they allow inhibiting a process at any desired time point, whereas mutating or altering the gene of an important regulator would likely result in a dead organism. With the advent of modern sequencing technology, it has become possible to monitor global cellular effects of small-molecule treatment and thereby overcome the limitations of classical biochemistry, which usually looks at a biological system in isolation. This review focuses on several molecules, especially natural products, that have played an important role in dissecting gene expression and have opened up new fields of investigation as well as clinical venues for disease treatment.
Collapse
Affiliation(s)
- Tilman Schneider-Poetsch
- Chemical Genomics Research Group, RIKEN Center for Sustainable Resource Science, Saitama 351-0198, Japan;
| | - Minoru Yoshida
- Chemical Genomics Research Group, RIKEN Center for Sustainable Resource Science, Saitama 351-0198, Japan; .,Department of Biotechnology, University of Tokyo, Tokyo 113-8657, Japan
| |
Collapse
|
41
|
Terenzio M, Koley S, Samra N, Rishal I, Zhao Q, Sahoo PK, Urisman A, Marvaldi L, Oses-Prieto JA, Forester C, Gomes C, Kalinski AL, Di Pizio A, Doron-Mandel E, Perry RBT, Koppel I, Twiss JL, Burlingame AL, Fainzilber M. Locally translated mTOR controls axonal local translation in nerve injury. Science 2018; 359:1416-1421. [PMID: 29567716 PMCID: PMC6501578 DOI: 10.1126/science.aan1053] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 12/13/2017] [Accepted: 01/30/2018] [Indexed: 12/12/2022]
Abstract
How is protein synthesis initiated locally in neurons? We found that mTOR (mechanistic target of rapamycin) was activated and then up-regulated in injured axons, owing to local translation of mTOR messenger RNA (mRNA). This mRNA was transported into axons by the cell size-regulating RNA-binding protein nucleolin. Furthermore, mTOR controlled local translation in injured axons. This included regulation of its own translation and that of retrograde injury signaling molecules such as importin β1 and STAT3 (signal transducer and activator of transcription 3). Deletion of the mTOR 3' untranslated region (3'UTR) in mice reduced mTOR in axons and decreased local translation after nerve injury. Both pharmacological inhibition of mTOR in axons and deletion of the mTOR 3'UTR decreased proprioceptive neuronal survival after nerve injury. Thus, mRNA localization enables spatiotemporal control of mTOR pathways regulating local translation and long-range intracellular signaling.
Collapse
Affiliation(s)
- Marco Terenzio
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sandip Koley
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Nitzan Samra
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ida Rishal
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Qian Zhao
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA
| | - Pabitra K Sahoo
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Anatoly Urisman
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA
| | - Letizia Marvaldi
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Juan A Oses-Prieto
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA
| | - Craig Forester
- Division of Pediatric Allergy, Immunology and Bone Marrow Transplantation, University of California, San Francisco, CA 94158, USA
| | - Cynthia Gomes
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Ashley L Kalinski
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Agostina Di Pizio
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ella Doron-Mandel
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Rotem Ben-Tov Perry
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Indrek Koppel
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Jeffery L Twiss
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Alma L Burlingame
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA
| | - Mike Fainzilber
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.
| |
Collapse
|
42
|
Moundoyi H, Demouy J, Le Panse S, Morales J, Sarels B, Cormier P. Toward Multiscale Modeling of Molecular and Biochemical Events Occurring at Fertilization Time in Sea Urchins. Results Probl Cell Differ 2018; 65:69-89. [DOI: 10.1007/978-3-319-92486-1_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
|
43
|
Punzo P, Ruggiero A, Grillo S, Batelli G. TIP41 network analysis and mutant phenotypes predict interactions between the TOR and ABA pathways. PLANT SIGNALING & BEHAVIOR 2018; 13:e1537698. [PMID: 30458658 PMCID: PMC6296354 DOI: 10.1080/15592324.2018.1537698] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 10/10/2018] [Accepted: 10/12/2018] [Indexed: 05/21/2023]
Abstract
Environmental conditions inform the rate of plant growth and development. The target of rapamycin (TOR) signalling pathway is a central regulator of plant growth in response to nutrients and energy, while abscisic acid (ABA) is a main mediator of abiotic stress responses. We recently characterized Arabidopsis TIP41, a predicted TOR pathway component involved in the ABA-mediated response to abiotic stress. Here, we report the ABA sensitivity of tip41 mutants, supporting the relation between TIP41 and the hormone pathway. The analysis of predicted TIP41 functional network identified several protein phosphatases. In particular, candidate protein interactors included catalytic subunits of type 2A protein phosphatases and protein phosphatases 6, which regulate different developmental processes and responses to environmental stimuli. These results provide important information on the role of TIP41 in the cross talk between TOR and ABA pathways.
Collapse
Affiliation(s)
- Paola Punzo
- National Research Council of Italy, Institute of Biosciences and Bioresources (CNR-IBBR), Portici, NA, Italy
| | - Alessandra Ruggiero
- National Research Council of Italy, Institute of Biosciences and Bioresources (CNR-IBBR), Portici, NA, Italy
- Department of Agricultural Science, University of Naples Federico II, Portici, NA, Italy
| | - Stefania Grillo
- National Research Council of Italy, Institute of Biosciences and Bioresources (CNR-IBBR), Portici, NA, Italy
| | - Giorgia Batelli
- National Research Council of Italy, Institute of Biosciences and Bioresources (CNR-IBBR), Portici, NA, Italy
- CONTACT Dr. Giorgia Batelli National Research Council of Italy, Institute of Biosciences and Bioresources (CNR-IBBR), Via Universita’, 133, 80055, Portici, NA, Italy
| |
Collapse
|
44
|
Multi-omics Comparative Analysis Reveals Multiple Layers of Host Signaling Pathway Regulation by the Gut Microbiota. mSystems 2017; 2:mSystems00107-17. [PMID: 29085914 PMCID: PMC5655592 DOI: 10.1128/msystems.00107-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 09/29/2017] [Indexed: 02/06/2023] Open
Abstract
Multiple host pathways were affected by its adaptation to the microbiota. We have found significant transcriptome-proteome discordance caused by the microbiota. This discovery leads to the definite conclusion that transcript-level analysis is not sufficient to predict protein levels and their influence on the function of many specific cellular pathways, so only analysis of combinations of the quantitative data determined at different levels will lead to a complete understanding of the complex relationships between the host and the microbiota. Therefore, our results demonstrate the importance of using an integrative approach to study host-microbiota interaction at the molecular level. The bodies of mammals are hosts to vast microbial communities composed of trillions of bacteria from thousands of species, whose effects on health and development have begun to be appreciated only recently. In this investigation, an integrated analysis combining proteomics and transcriptomics was used to quantitatively compare the terminal ilia from conventional and germfree mice. Female and male mice responded similarly to the microbiota, but C57BL/10A mice responded more strongly than BALB/c mice at both the transcriptome and proteome levels. The microbiota primarily caused upregulation of immunological pathways and downregulation of metabolic pathways in the conventional mice. Many of the affected pathways were altered only at either the transcriptome or proteome level. Of the pathways that were affected at both levels, most were affected concordantly. The discordant pathways were not principally involved in the immune system but instead were related to metabolism, oxidative phosphorylation, protein translation, transport, and turnover. To broaden the discovery of affected host pathways, a meta-analysis was performed using intestinal transcriptomics data from previously published studies of germfree versus conventional mice with diverse microbiota populations. Similar transcript-level responses to the microbiota were found, and many additional affected host pathways were discovered. IMPORTANCE Multiple host pathways were affected by its adaptation to the microbiota. We have found significant transcriptome-proteome discordance caused by the microbiota. This discovery leads to the definite conclusion that transcript-level analysis is not sufficient to predict protein levels and their influence on the function of many specific cellular pathways, so only analysis of combinations of the quantitative data determined at different levels will lead to a complete understanding of the complex relationships between the host and the microbiota. Therefore, our results demonstrate the importance of using an integrative approach to study host-microbiota interaction at the molecular level.
Collapse
|
45
|
Gruss OJ, Meduri R, Schilling M, Fischer U. UsnRNP biogenesis: mechanisms and regulation. Chromosoma 2017; 126:577-593. [PMID: 28766049 DOI: 10.1007/s00412-017-0637-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/14/2017] [Accepted: 07/14/2017] [Indexed: 12/24/2022]
Abstract
Macromolecular complexes composed of proteins or proteins and nucleic acids rather than individual macromolecules mediate many cellular activities. Maintenance of these activities is essential for cell viability and requires the coordinated production of the individual complex components as well as their faithful incorporation into functional entities. Failure of complex assembly may have fatal consequences and can cause severe diseases. While many macromolecular complexes can form spontaneously in vitro, they often require aid from assembly factors including assembly chaperones in the crowded cellular environment. The assembly of RNA protein complexes implicated in the maturation of pre-mRNAs (termed UsnRNPs) has proven to be a paradigm to understand the action of assembly factors and chaperones. UsnRNPs are assembled by factors united in protein arginine methyltransferase 5 (PRMT5)- and survival motor neuron (SMN)-complexes, which act sequentially in the UsnRNP production line. While the PRMT5-complex pre-arranges specific sets of proteins into stable intermediates, the SMN complex displaces assembly factors from these intermediates and unites them with UsnRNA to form the assembled RNP. Despite advanced mechanistic understanding of UsnRNP assembly, our knowledge of regulatory features of this essential and ubiquitous cellular function remains remarkably incomplete. One may argue that the process operates as a default biosynthesis pathway and does not require sophisticated regulatory cues. Simple theoretical considerations and a number of experimental data, however, indicate that regulation of UsnRNP assembly most likely happens at multiple levels. This review will not only summarize how individual components of this assembly line act mechanistically but also why, how, and when the UsnRNP workflow might be regulated by means of posttranslational modification in response to cellular signaling cues.
Collapse
Affiliation(s)
- Oliver J Gruss
- Department of Genetics, Rheinische Friedrich-Wilhelms-Universität Bonn, Karlrobert-Kreiten-Str. 13, 53115, Bonn, Germany.
| | - Rajyalakshmi Meduri
- Department of Biochemistry, University of Würzburg, Biozentrum, Am Hubland, D-97074, Würzburg, Germany
| | - Maximilian Schilling
- Department of Genetics, Rheinische Friedrich-Wilhelms-Universität Bonn, Karlrobert-Kreiten-Str. 13, 53115, Bonn, Germany
| | - Utz Fischer
- Department of Biochemistry, University of Würzburg, Biozentrum, Am Hubland, D-97074, Würzburg, Germany.
| |
Collapse
|
46
|
Navarro BV, Elbl P, De Souza AP, Jardim V, de Oliveira LF, Macedo AF, dos Santos ALW, Buckeridge MS, Floh EIS. Carbohydrate-mediated responses during zygotic and early somatic embryogenesis in the endangered conifer, Araucaria angustifolia. PLoS One 2017; 12:e0180051. [PMID: 28678868 PMCID: PMC5497979 DOI: 10.1371/journal.pone.0180051] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 06/08/2017] [Indexed: 12/30/2022] Open
Abstract
Three zygotic developmental stages and two somatic Araucaria angustifolia cell lines with contrasting embryogenic potential were analyzed to identify the carbohydrate-mediated responses associated with embryo formation. Using a comparison between zygotic and somatic embryogenesis systems, the non-structural carbohydrate content, cell wall sugar composition and expression of genes involved in sugar sensing were analyzed, and a network analysis was used to identify coordinated features during embryogenesis. We observed that carbohydrate-mediated responses occur mainly during the early stages of zygotic embryo formation, and that during seed development there are coordinated changes that affect the development of the different structures (embryo and megagametophyte). Furthermore, sucrose and starch accumulation were associated with the responsiveness of the cell lines. This study sheds light on how carbohydrate metabolism is influenced during zygotic and somatic embryogenesis in the endangered conifer species, A. angustifolia.
Collapse
Affiliation(s)
- Bruno V. Navarro
- Laboratory of Plant Cell Biology, Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo-SP, Brazil
| | - Paula Elbl
- Laboratory of Plant Cell Biology, Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo-SP, Brazil
| | - Amanda P. De Souza
- Laboratory of Plant Physiological Ecology, Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo-SP, Brazil
| | - Vinicius Jardim
- Laboratory of Plant Physiological Ecology, Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo-SP, Brazil
| | - Leandro F. de Oliveira
- Laboratory of Plant Cell Biology, Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo-SP, Brazil
| | - Amanda F. Macedo
- Laboratory of Plant Cell Biology, Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo-SP, Brazil
| | - André L. W. dos Santos
- Laboratory of Plant Cell Biology, Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo-SP, Brazil
| | - Marcos S. Buckeridge
- Laboratory of Plant Physiological Ecology, Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo-SP, Brazil
| | - Eny I. S. Floh
- Laboratory of Plant Cell Biology, Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo-SP, Brazil
- * E-mail:
| |
Collapse
|
47
|
Gamberi C, Hipfner DR, Trudel M, Lubell WD. Bicaudal C mutation causes myc and TOR pathway up-regulation and polycystic kidney disease-like phenotypes in Drosophila. PLoS Genet 2017; 13:e1006694. [PMID: 28406902 PMCID: PMC5390980 DOI: 10.1371/journal.pgen.1006694] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 03/15/2017] [Indexed: 12/26/2022] Open
Abstract
Progressive cystic kidney degeneration underlies diverse renal diseases, including the most common cause of kidney failure, autosomal dominant Polycystic Kidney Disease (PKD). Genetic analyses of patients and animal models have identified several key drivers of this disease. The precise molecular and cellular changes underlying cystogenesis remain, however, elusive. Drosophila mutants lacking the translational regulator Bicaudal C (BicC, the fly ortholog of vertebrate BICC1 implicated in renal cystogenesis) exhibited progressive cystic degeneration of the renal tubules (so called “Malpighian” tubules) and reduced renal function. The BicC protein was shown to bind to Drosophila (d-) myc mRNA in tubules. Elevation of d-Myc protein levels was a cause of tubular degeneration in BicC mutants. Activation of the Target of Rapamycin (TOR) kinase pathway, another common feature of PKD, was found in BicC mutant flies. Rapamycin administration substantially reduced the cystic phenotype in flies. We present new mechanistic insight on BicC function and propose that Drosophila may serve as a genetically tractable model for dissecting the evolutionarily-conserved molecular mechanisms of renal cystogenesis. Polycystic kidney disease (PKD) is a degenerative, potentially lethal, genetic malady that affects 12.5 million people world-wide for which there is no cure. In the kidney, PKD causes the formation of prominent, fluid-filled cysts the growth of which damages progressively kidney function. Crucial to PKD development, mutations in the PKD1 and PKD2 genes cause renal cystic degeneration via factors and mechanisms that are only partially known. This manuscript reports novel insights into the molecular mechanisms of the evolutionarily conserved RNA binding protein BicC, which has been implicated in vertebrate cystic kidney diseases. The BicC mutants of the fruit fly Drosophila melanogaster recapitulate crucial characteristics of PKD. A clear link between BicC and PKD has begun to emerge, in part because both PKD1 patients and Pkd1 mice exhibit reduced BicC function. This first in kind Drosophila model of renal cystogenesis offers strong potential to decipher the complex mechanisms of the molecular and cellular changes causing renal cyst formation.
Collapse
Affiliation(s)
- Chiara Gamberi
- Department of Biology, Concordia University, Montréal, QC, Canada
- * E-mail:
| | - David R. Hipfner
- Institut de recherches cliniques de Montréal, 110 Pine Avenue West, Montréal, QC, Canada
- Département de médecine, Université de Montréal, Montréal, QC, Canada
| | - Marie Trudel
- Institut de recherches cliniques de Montréal, 110 Pine Avenue West, Montréal, QC, Canada
- Département de médecine, Université de Montréal, Montréal, QC, Canada
| | | |
Collapse
|
48
|
Lahr RM, Fonseca BD, Ciotti GE, Al-Ashtal HA, Jia JJ, Niklaus MR, Blagden SP, Alain T, Berman AJ. La-related protein 1 (LARP1) binds the mRNA cap, blocking eIF4F assembly on TOP mRNAs. eLife 2017. [PMID: 28379136 DOI: 10.7554/elife.24146.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The 5'terminal oligopyrimidine (5'TOP) motif is a cis-regulatory RNA element located immediately downstream of the 7-methylguanosine [m7G] cap of TOP mRNAs, which encode ribosomal proteins and translation factors. In eukaryotes, this motif coordinates the synchronous and stoichiometric expression of the protein components of the translation machinery. La-related protein 1 (LARP1) binds TOP mRNAs, regulating their stability and translation. We present crystal structures of the human LARP1 DM15 region in complex with a 5'TOP motif, a cap analog (m7GTP), and a capped cytidine (m7GpppC), resolved to 2.6, 1.8 and 1.7 Å, respectively. Our binding, competition, and immunoprecipitation data corroborate and elaborate on the mechanism of 5'TOP motif binding by LARP1. We show that LARP1 directly binds the cap and adjacent 5'TOP motif of TOP mRNAs, effectively impeding access of eIF4E to the cap and preventing eIF4F assembly. Thus, LARP1 is a specialized TOP mRNA cap-binding protein that controls ribosome biogenesis.
Collapse
Affiliation(s)
- Roni M Lahr
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
| | - Bruno D Fonseca
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - Gabrielle E Ciotti
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
| | - Hiba A Al-Ashtal
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
| | - Jian-Jun Jia
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - Marius R Niklaus
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - Sarah P Blagden
- Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Tommy Alain
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - Andrea J Berman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
| |
Collapse
|
49
|
Lahr RM, Fonseca BD, Ciotti GE, Al-Ashtal HA, Jia JJ, Niklaus MR, Blagden SP, Alain T, Berman AJ. La-related protein 1 (LARP1) binds the mRNA cap, blocking eIF4F assembly on TOP mRNAs. eLife 2017; 6:e24146. [PMID: 28379136 PMCID: PMC5419741 DOI: 10.7554/elife.24146] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 04/04/2017] [Indexed: 01/07/2023] Open
Abstract
The 5'terminal oligopyrimidine (5'TOP) motif is a cis-regulatory RNA element located immediately downstream of the 7-methylguanosine [m7G] cap of TOP mRNAs, which encode ribosomal proteins and translation factors. In eukaryotes, this motif coordinates the synchronous and stoichiometric expression of the protein components of the translation machinery. La-related protein 1 (LARP1) binds TOP mRNAs, regulating their stability and translation. We present crystal structures of the human LARP1 DM15 region in complex with a 5'TOP motif, a cap analog (m7GTP), and a capped cytidine (m7GpppC), resolved to 2.6, 1.8 and 1.7 Å, respectively. Our binding, competition, and immunoprecipitation data corroborate and elaborate on the mechanism of 5'TOP motif binding by LARP1. We show that LARP1 directly binds the cap and adjacent 5'TOP motif of TOP mRNAs, effectively impeding access of eIF4E to the cap and preventing eIF4F assembly. Thus, LARP1 is a specialized TOP mRNA cap-binding protein that controls ribosome biogenesis.
Collapse
Affiliation(s)
- Roni M Lahr
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
| | - Bruno D Fonseca
- Children’s Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - Gabrielle E Ciotti
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
| | - Hiba A Al-Ashtal
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
| | - Jian-Jun Jia
- Children’s Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - Marius R Niklaus
- Children’s Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - Sarah P Blagden
- Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Tommy Alain
- Children’s Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - Andrea J Berman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
| |
Collapse
|
50
|
Huang L, Yang M, Yuan Y, Li X, Kuang E. Niclosamide inhibits lytic replication of Epstein-Barr virus by disrupting mTOR activation. Antiviral Res 2016; 138:68-78. [PMID: 27939840 DOI: 10.1016/j.antiviral.2016.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 11/30/2016] [Accepted: 12/05/2016] [Indexed: 12/31/2022]
Abstract
Infection with the oncogenic γ-herpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) cause several severe malignancies in humans. Inhibition of the lytic replication of EBV and KSHV eliminates the reservoir of persistent infection and transmission, consequently preventing the occurrence of diseases from the sources of infection. Antiviral drugs are limited in controlling these viral infectious diseases. Here, we demonstrate that niclosamide, an old anthelmintic drug, inhibits mTOR activation during EBV lytic replication. Consequently, niclosamide effectively suppresses EBV lytic gene expression, viral DNA lytic replication and virion production in EBV-infected lymphoma cells and epithelial cells. Niclosamide exhibits cytotoxicity toward lymphoma cells and induces irreversible cell cycle arrest in lytically EBV-infected cells. The ectopic overexpression of mTOR reverses the inhibition of niclosamide in EBV lytic replication. Similarly, niclosamide inhibits KSHV lytic replication. Thus, we conclude that niclosamide is a promising candidate for chemotherapy against the acute occurrence and transmission of infectious diseases of oncogenic γ-herpesviruses.
Collapse
Affiliation(s)
- Lu Huang
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Mengtian Yang
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Yan Yuan
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Xiaojuan Li
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China.
| | - Ersheng Kuang
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China; Key Laboratory of Tropical Disease Control (Sun Yat-Sen University), Ministry of Education, Guangzhou, China.
| |
Collapse
|