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Sambri I, Ferniani M, Ballabio A. Ragopathies and the rising influence of RagGTPases on human diseases. Nat Commun 2024; 15:5812. [PMID: 38987251 PMCID: PMC11237164 DOI: 10.1038/s41467-024-50034-4] [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: 02/23/2024] [Accepted: 06/27/2024] [Indexed: 07/12/2024] Open
Abstract
RagGTPases (Rags) play an essential role in the regulation of cell metabolism by controlling the activities of both mechanistic target of rapamycin complex 1 (mTORC1) and Transcription factor EB (TFEB). Several diseases, herein named ragopathies, are associated to Rags dysfunction. These diseases may be caused by mutations either in genes encoding the Rags, or in their upstream regulators. The resulting phenotypes may encompass a variety of clinical features such as cataract, kidney tubulopathy, dilated cardiomyopathy and several types of cancer. In this review, we focus on the key clinical, molecular and physio-pathological features of ragopathies, aiming to shed light on their underlying mechanisms.
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Affiliation(s)
- Irene Sambri
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, (NA), Italy
- Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine Program (GEM), Naples, Italy
| | - Marco Ferniani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, USA
| | - Andrea Ballabio
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, (NA), Italy.
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, USA.
- Medical Genetics Unit, Department of Medical and Translational Science, Federico II University, Naples, Italy.
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2
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Zhu X, Wu Y, Li Y, Zhou X, Watzlawik JO, Chen YM, Raybuck AL, Billadeau D, Shapiro V, Springer W, Sun J, Boothby MR, Zeng H. Rag-GTPase-TFEB/TFE3 axis controls B cell mitochondrial fitness and humoral immunity independent of mTORC1. RESEARCH SQUARE 2024:rs.3.rs-3957355. [PMID: 38585731 PMCID: PMC10996787 DOI: 10.21203/rs.3.rs-3957355/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
During the humoral immune response, B cells undergo rapid metabolic reprogramming with a high demand for nutrients, which are vital to sustain the formation of the germinal centers (GCs). Rag-GTPases sense amino acid availability to modulate the mechanistic target of rapamycin complex 1 (mTORC1) pathway and suppress transcription factor EB (TFEB) and transcription factor enhancer 3 (TFE3), members of the microphthalmia (MiT/TFE) family of HLH-leucine zipper transcription factors. However, how Rag-GTPases coordinate amino acid sensing, mTORC1 activation, and TFEB/TFE3 activity in humoral immunity remains undefined. Here, we show that B cell-intrinsic Rag-GTPases are critical for the development and activation of B cells. RagA/RagB deficient B cells fail to form GCs, produce antibodies, and generate plasmablasts in both T-dependent (TD) and T-independent (TI) humoral immune responses. Deletion of RagA/RagB in GC B cells leads to abnormal dark zone (DZ) to light zone (LZ) ratio and reduced affinity maturation. Mechanistically, the Rag-GTPase complex constrains TFEB/TFE3 activity to prevent mitophagy dysregulation and maintain mitochondrial fitness in B cells, which are independent of canonical mTORC1 activation. TFEB/TFE3 deletion restores B cell development, GC formation in Peyer's patches and TI humoral immunity, but not TD humoral immunity in the absence of Rag-GTPases. Collectively, our data establish Rag-GTPase-TFEB/TFE3 axis as an mTORC1 independent mechanism to coordinating nutrient sensing and mitochondrial metabolism in B cells.
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Affiliation(s)
- Xingxing Zhu
- Division of Rheumatology, Department of Medicine, Mayo Clinic Rochester, MN 55905, USA
| | - Yue Wu
- Carter Immunology Center, University of Virginia, Charlottesville, VA 22908, USA
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA 22908, USA
| | - Yanfeng Li
- Division of Rheumatology, Department of Medicine, Mayo Clinic Rochester, MN 55905, USA
| | - Xian Zhou
- Division of Rheumatology, Department of Medicine, Mayo Clinic Rochester, MN 55905, USA
| | - Jens O Watzlawik
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Yin Maggie Chen
- Department of Immunology, Mayo Clinic Rochester, MN 55905, USA
| | - Ariel L Raybuck
- Department of Pathology, Microbiology & Immunology, Molecular Pathogenesis Division, Vanderbilt University Medical Center and School of Medicine, Nashville, TN 37232, USA
| | | | | | - Wolfdieter Springer
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
- Neuroscience PhD Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL 32224, USA
| | - Jie Sun
- Carter Immunology Center, University of Virginia, Charlottesville, VA 22908, USA
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA 22908, USA
| | - Mark R Boothby
- Department of Pathology, Microbiology & Immunology, Molecular Pathogenesis Division, Vanderbilt University Medical Center and School of Medicine, Nashville, TN 37232, USA
| | - Hu Zeng
- Division of Rheumatology, Department of Medicine, Mayo Clinic Rochester, MN 55905, USA
- Department of Immunology, Mayo Clinic Rochester, MN 55905, USA
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3
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Zhu X, Wu Y, Li Y, Zhou X, Watzlawik JO, Chen YM, Raybuck AL, Billadeau D, Shapiro V, Springer W, Sun J, Boothby MR, Zeng H. The nutrient-sensing Rag-GTPase complex in B cells controls humoral immunity via TFEB/TFE3-dependent mitochondrial fitness. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.26.582122. [PMID: 38463988 PMCID: PMC10925109 DOI: 10.1101/2024.02.26.582122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
During the humoral immune response, B cells undergo rapid metabolic reprogramming with a high demand for nutrients, which are vital to sustain the formation of the germinal centers (GCs). Rag-GTPases sense amino acid availability to modulate the mechanistic target of rapamycin complex 1 (mTORC1) pathway and suppress transcription factor EB (TFEB) and transcription factor enhancer 3 (TFE3), members of the microphthalmia (MiT/TFE) family of HLH-leucine zipper transcription factors. However, how Rag-GTPases coordinate amino acid sensing, mTORC1 activation, and TFEB/TFE3 activity in humoral immunity remains undefined. Here, we show that B cell-intrinsic Rag-GTPases are critical for the development and activation of B cells. RagA/RagB deficient B cells fail to form GCs, produce antibodies, and generate plasmablasts in both T-dependent (TD) and T-independent (TI) humoral immune responses. Deletion of RagA/RagB in GC B cells leads to abnormal dark zone (DZ) to light zone (LZ) ratio and reduced affinity maturation. Mechanistically, the Rag-GTPase complex constrains TFEB/TFE3 activity to prevent mitophagy dysregulation and maintain mitochondrial fitness in B cells, which are independent of canonical mTORC1 activation. TFEB/TFE3 deletion restores B cell development, GC formation in Peyer's patches and TI humoral immunity, but not TD humoral immunity in the absence of Rag-GTPases. Collectively, our data establish Rag-GTPase-TFEB/TFE3 pathway as an mTORC1 independent mechanism to coordinating nutrient sensing and mitochondrial metabolism in B cells.
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Affiliation(s)
- Xingxing Zhu
- Division of Rheumatology, Department of Medicine, Mayo Clinic Rochester, MN 55905, USA
| | - Yue Wu
- Carter Immunology Center, University of Virginia, Charlottesville, VA 22908, USA
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA 22908, USA
| | - Yanfeng Li
- Division of Rheumatology, Department of Medicine, Mayo Clinic Rochester, MN 55905, USA
| | - Xian Zhou
- Division of Rheumatology, Department of Medicine, Mayo Clinic Rochester, MN 55905, USA
| | - Jens O Watzlawik
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Yin Maggie Chen
- Department of Immunology, Mayo Clinic Rochester, MN 55905, USA
| | - Ariel L Raybuck
- Department of Pathology, Microbiology & Immunology, Molecular Pathogenesis Division, Vanderbilt University Medical Center and School of Medicine, Nashville, TN 37232, USA
| | | | | | - Wolfdieter Springer
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
- Neuroscience PhD Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL 32224, USA
| | - Jie Sun
- Carter Immunology Center, University of Virginia, Charlottesville, VA 22908, USA
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA 22908, USA
| | - Mark R Boothby
- Department of Pathology, Microbiology & Immunology, Molecular Pathogenesis Division, Vanderbilt University Medical Center and School of Medicine, Nashville, TN 37232, USA
| | - Hu Zeng
- Division of Rheumatology, Department of Medicine, Mayo Clinic Rochester, MN 55905, USA
- Department of Immunology, Mayo Clinic Rochester, MN 55905, USA
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4
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Smith HJ, Lanjuin A, Sharma A, Prabhakar A, Nowak E, Stine PG, Sehgal R, Stojanovski K, Towbin BD, Mair WB. Neuronal mTORC1 inhibition promotes longevity without suppressing anabolic growth and reproduction in C. elegans. PLoS Genet 2023; 19:e1010938. [PMID: 37721956 PMCID: PMC10538657 DOI: 10.1371/journal.pgen.1010938] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 09/28/2023] [Accepted: 08/24/2023] [Indexed: 09/20/2023] Open
Abstract
mTORC1 (mechanistic target of rapamycin complex 1) is a metabolic sensor that promotes growth when nutrients are abundant. Ubiquitous inhibition of mTORC1 extends lifespan in multiple organisms but also disrupts several anabolic processes resulting in stunted growth, slowed development, reduced fertility, and disrupted metabolism. However, it is unclear if these pleiotropic effects of mTORC1 inhibition can be uncoupled from longevity. Here, we utilize the auxin-inducible degradation (AID) system to restrict mTORC1 inhibition to C. elegans neurons. We find that neuron-specific degradation of RAGA-1, an upstream activator of mTORC1, or LET-363, the ortholog of mammalian mTOR, is sufficient to extend lifespan in C. elegans. Unlike raga-1 loss of function genetic mutations or somatic AID of RAGA-1, neuronal AID of RAGA-1 robustly extends lifespan without impairing body size, developmental rate, brood size, or neuronal function. Moreover, while degradation of RAGA-1 in all somatic tissues alters the expression of thousands of genes, demonstrating the widespread effects of mTORC1 inhibition, degradation of RAGA-1 in neurons only results in around 200 differentially expressed genes with a specific enrichment in metabolism and stress response. Notably, our work demonstrates that targeting mTORC1 specifically in the nervous system in C. elegans uncouples longevity from growth and reproductive impairments, and that many canonical effects of low mTORC1 activity are not required to promote healthy aging. These data challenge previously held ideas about the mechanisms of mTORC1 lifespan extension and underscore the potential of promoting longevity by neuron-specific mTORC1 modulation.
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Affiliation(s)
- Hannah J. Smith
- Dept. Molecular Metabolism, Harvard TH Chan School of Public Health, Massachusetts, United States of America
| | - Anne Lanjuin
- Dept. Molecular Metabolism, Harvard TH Chan School of Public Health, Massachusetts, United States of America
| | - Arpit Sharma
- Dept. Molecular Metabolism, Harvard TH Chan School of Public Health, Massachusetts, United States of America
| | - Aditi Prabhakar
- Dept. Molecular Metabolism, Harvard TH Chan School of Public Health, Massachusetts, United States of America
| | - Ewelina Nowak
- Dept. Molecular Metabolism, Harvard TH Chan School of Public Health, Massachusetts, United States of America
| | - Peter G. Stine
- Dept. Molecular Metabolism, Harvard TH Chan School of Public Health, Massachusetts, United States of America
| | - Rohan Sehgal
- Dept. Molecular Metabolism, Harvard TH Chan School of Public Health, Massachusetts, United States of America
| | | | | | - William B. Mair
- Dept. Molecular Metabolism, Harvard TH Chan School of Public Health, Massachusetts, United States of America
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5
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Silva-García CG. Devo-Aging: Intersections Between Development and Aging. GeroScience 2023; 45:2145-2159. [PMID: 37160658 PMCID: PMC10651630 DOI: 10.1007/s11357-023-00809-2] [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: 12/30/2022] [Accepted: 04/25/2023] [Indexed: 05/11/2023] Open
Abstract
There are two fundamental questions in developmental biology. How does a single fertilized cell give rise to a whole body? and how does this body later produce progeny? Synchronization of these embryonic and postembryonic developments ensures continuity of life from one generation to the next. An enormous amount of work has been done to unravel the molecular mechanisms behind these processes, but more recently, modern developmental biology has been expanded to study development in wider contexts, including regeneration, environment, disease, and even aging. However, we have just started to understand how the mechanisms that govern development also regulate aging. This review discusses examples of signaling pathways involved in development to elucidate how their regulation influences healthspan and lifespan. Therefore, a better knowledge of developmental signaling pathways stresses the possibility of using them as innovative biomarkers and targets for aging and age-related diseases.
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Affiliation(s)
- Carlos Giovanni Silva-García
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA.
- Center on the Biology of Aging, Brown University, Providence, RI, USA.
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6
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Zhang X, Li S, Malik I, Do MH, Ji L, Chou C, Shi W, Capistrano KJ, Zhang J, Hsu TW, Nixon BG, Xu K, Wang X, Ballabio A, Schmidt LS, Linehan WM, Li MO. Reprogramming tumour-associated macrophages to outcompete cancer cells. Nature 2023; 619:616-623. [PMID: 37380769 PMCID: PMC10719927 DOI: 10.1038/s41586-023-06256-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 05/24/2023] [Indexed: 06/30/2023]
Abstract
In metazoan organisms, cell competition acts as a quality control mechanism to eliminate unfit cells in favour of their more robust neighbours1,2. This mechanism has the potential to be maladapted, promoting the selection of aggressive cancer cells3-6. Tumours are metabolically active and are populated by stroma cells7,8, but how environmental factors affect cancer cell competition remains largely unknown. Here we show that tumour-associated macrophages (TAMs) can be dietarily or genetically reprogrammed to outcompete MYC-overexpressing cancer cells. In a mouse model of breast cancer, MYC overexpression resulted in an mTORC1-dependent 'winner' cancer cell state. A low-protein diet inhibited mTORC1 signalling in cancer cells and reduced tumour growth, owing unexpectedly to activation of the transcription factors TFEB and TFE3 and mTORC1 in TAMs. Diet-derived cytosolic amino acids are sensed by Rag GTPases through the GTPase-activating proteins GATOR1 and FLCN to control Rag GTPase effectors including TFEB and TFE39-14. Depletion of GATOR1 in TAMs suppressed the activation of TFEB, TFE3 and mTORC1 under the low-protein diet condition, causing accelerated tumour growth; conversely, depletion of FLCN or Rag GTPases in TAMs activated TFEB, TFE3 and mTORC1 under the normal protein diet condition, causing decelerated tumour growth. Furthermore, mTORC1 hyperactivation in TAMs and cancer cells and their competitive fitness were dependent on the endolysosomal engulfment regulator PIKfyve. Thus, noncanonical engulfment-mediated Rag GTPase-independent mTORC1 signalling in TAMs controls competition between TAMs and cancer cells, which defines a novel innate immune tumour suppression pathway that could be targeted for cancer therapy.
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Affiliation(s)
- Xian Zhang
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Shun Li
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Isha Malik
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Mytrang H Do
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY, USA
| | - Liangliang Ji
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Chun Chou
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Wei Shi
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Kristelle J Capistrano
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Jing Zhang
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Ting-Wei Hsu
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Graduate Program in Biochemistry and Structural Biology, Cell and Developmental Biology, and Molecular Biology, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY, USA
| | - Briana G Nixon
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY, USA
| | - Ke Xu
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY, USA
- META Pharmaceuticals, Shenzhen, China
| | - Xinxin Wang
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY, USA
| | - Andrea Ballabio
- Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy
- Medical Genetics Unit, Department of Medical and Translational Science, Federico II University, Naples, Italy
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, USA
| | - Laura S Schmidt
- Urologic Oncology Branch, National Cancer Institute, Bethesda, MD, USA
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - W Marston Linehan
- Urologic Oncology Branch, National Cancer Institute, Bethesda, MD, USA
| | - Ming O Li
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
- Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY, USA.
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7
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Regulation of mTORC1 by the Rag GTPases. Biochem Soc Trans 2023; 51:655-664. [PMID: 36929165 DOI: 10.1042/bst20210038] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 03/18/2023]
Abstract
The Rag GTPases are an evolutionarily conserved family that play a crucial role in amino acid sensing by the mammalian target of rapamycin complex 1 (mTORC1). mTORC1 is often referred to as the master regulator of cell growth. mTORC1 hyperactivation is observed in multiple diseases such as cancer, obesity, metabolic disorders, and neurodegeneration. The Rag GTPases sense amino acid levels and form heterodimers, where RagA or RagB binds to RagC or RagD, to recruit mTORC1 to the lysosome where it becomes activated. Here, we review amino acid signaling to mTORC1 through the Rag GTPases.
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8
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Deleyto-Seldas N, Efeyan A. AMPK knocks at the gate of GATOR. Nat Metab 2023; 5:197-198. [PMID: 36732623 DOI: 10.1038/s42255-022-00729-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
| | - Alejo Efeyan
- Spanish National Cancer Research Center, Madrid, Spain.
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9
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Dai X, Jiang C, Jiang Q, Fang L, Yu H, Guo J, Yan P, Chi F, Zhang T, Inuzuka H, Asara JM, Wang P, Guo J, Wei W. AMPK-dependent phosphorylation of the GATOR2 component WDR24 suppresses glucose-mediated mTORC1 activation. Nat Metab 2023; 5:265-276. [PMID: 36732624 PMCID: PMC11070849 DOI: 10.1038/s42255-022-00732-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 12/20/2022] [Indexed: 02/04/2023]
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) controls cell growth in response to amino acid and glucose levels. However, how mTORC1 senses glucose availability to regulate various downstream signalling pathways remains largely elusive. Here we report that AMP-activated protein kinase (AMPK)-mediated phosphorylation of WDR24, a core component of the GATOR2 complex, has a role in the glucose-sensing capability of mTORC1. Mechanistically, glucose deprivation activates AMPK, which directly phosphorylates WDR24 on S155, subsequently disrupting the integrity of the GATOR2 complex to suppress mTORC1 activation. Phosphomimetic Wdr24S155D knock-in mice exhibit early embryonic lethality and reduced mTORC1 activity. On the other hand, compared to wild-type littermates, phospho-deficient Wdr24S155A knock-in mice are more resistant to fasting and display elevated mTORC1 activity. Our findings reveal that AMPK-mediated phosphorylation of WDR24 modulates glucose-induced mTORC1 activation, thereby providing a rationale for targeting AMPK-WDR24 signalling to fine-tune mTORC1 activation as a potential therapeutic means to combat human diseases with aberrant activation of mTORC1 signalling including cancer.
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Affiliation(s)
- Xiaoming Dai
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Cong Jiang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Qiwei Jiang
- Institute of Precision Medicine, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Lan Fang
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Haihong Yu
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jinhe Guo
- Institute of Precision Medicine, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Peiqiang Yan
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Fangtao Chi
- The David H. Koch Institute for Integrative Cancer Research at Massachusetts Institute of Technology, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Tao Zhang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Hiroyuki Inuzuka
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - John M Asara
- Division of Signal Transduction, Beth Israel Deaconess Medical Center and Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Ping Wang
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jianping Guo
- Institute of Precision Medicine, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
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10
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Jiang C, Dai X, He S, Zhou H, Fang L, Guo J, Liu S, Zhang T, Pan W, Yu H, Fu T, Li D, Inuzuka H, Wang P, Xiao J, Wei W. Ring domains are essential for GATOR2-dependent mTORC1 activation. Mol Cell 2023; 83:74-89.e9. [PMID: 36528027 PMCID: PMC11027793 DOI: 10.1016/j.molcel.2022.11.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 09/14/2022] [Accepted: 11/22/2022] [Indexed: 12/23/2022]
Abstract
The GATOR2-GATOR1 signaling axis is essential for amino-acid-dependent mTORC1 activation. However, the molecular function of the GATOR2 complex remains unknown. Here, we report that disruption of the Ring domains of Mios, WDR24, or WDR59 completely impedes amino-acid-mediated mTORC1 activation. Mechanistically, via interacting with Ring domains of WDR59 and WDR24, the Ring domain of Mios acts as a hub to maintain GATOR2 integrity, disruption of which leads to self-ubiquitination of WDR24. Physiologically, leucine stimulation dissociates Sestrin2 from the Ring domain of WDR24 and confers its availability to UBE2D3 and subsequent ubiquitination of NPRL2, contributing to GATOR2-mediated GATOR1 inactivation. As such, WDR24 ablation or Ring deletion prevents mTORC1 activation, leading to severe growth defects and embryonic lethality at E10.5 in mice. Hence, our findings demonstrate that Ring domains are essential for GATOR2 to transmit amino acid availability to mTORC1 and further reveal the essentiality of nutrient sensing during embryonic development.
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Affiliation(s)
- Cong Jiang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Xiaoming Dai
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Shaohui He
- Joint Research Center for Musculoskeletal Tumor of Shanghai Changzheng Hospital and University of Shanghai for Science and Technology, Spinal Tumor Center, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Shanghai 200003, China
| | - Hongfei Zhou
- Joint Research Center for Musculoskeletal Tumor of Shanghai Changzheng Hospital and University of Shanghai for Science and Technology, Spinal Tumor Center, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Shanghai 200003, China
| | - Lan Fang
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai 200092, China
| | - Jianping Guo
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Songlei Liu
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Tao Zhang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Weijuan Pan
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Haihong Yu
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai 200092, China
| | - Tianmin Fu
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH 43210, USA
| | - Dali Li
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Hiroyuki Inuzuka
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Ping Wang
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai 200092, China
| | - Jianru Xiao
- Joint Research Center for Musculoskeletal Tumor of Shanghai Changzheng Hospital and University of Shanghai for Science and Technology, Spinal Tumor Center, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Shanghai 200003, China.
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA.
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11
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Jiang W, Ou Z, Zhu Q, Zai H. RagC GTPase regulates mTOR to promote chemoresistance in senescence-like HepG2 cells. Front Physiol 2022; 13:949737. [PMID: 36267578 PMCID: PMC9577253 DOI: 10.3389/fphys.2022.949737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 09/20/2022] [Indexed: 11/23/2022] Open
Abstract
Radiotherapy and chemotherapy can arrest cancer cells in a senescence-like state, which can lead to therapy resistance and cancer relapse. mTOR is hyperactivated in senescent cells but the mechanisms remain unclear. In this study, we examine the roles of several mTOR-regulated GTPases in senescence-like liver cancer cells and the mechanisms in drug resistance. We show that although RagC, Rheb, Rab1A, Rab5 and Arf1 GTPases were required for optimal mTOR activation in proliferating HepG2 cells, only RagC and Rheb are required in the senescence-like counterparts. Consistently, the drug resistance of the senescence-like HepG2 can be reduced by knocking down RagC and Rheb but not the other GTPases. Autophagic and lysosomal activity were increased in senescence-like cells; pharmacological inhibition of autophagy-lysosome decreased mTOR activity and preferentially sensitized senescence-like HepG2 cells to chemotherapy drugs including trametinib, cisplatin, and doxorubicin. In liver cancer patients, expression of RagC and Rheb but not other GTPases examined was associated with unfavorable prognosis. Our study therefore has defined a key role of Rag-Rheb GTPase in mediating mTOR activation and drug resistance in senescence-like HepG2 cells, which could have important implications in developing second-line treatments for liver cancer patients.
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Affiliation(s)
- Wei Jiang
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Central South University, Changsha, Hunan, China
| | - Zhenglin Ou
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Central South University, Changsha, Hunan, China
| | - Qin Zhu
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Central South University, Changsha, Hunan, China
| | - Hongyan Zai
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Central South University, Changsha, Hunan, China
- *Correspondence: Hongyan Zai,
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12
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Figlia G, Müller S, Hagenston AM, Kleber S, Roiuk M, Quast JP, Ten Bosch N, Carvajal Ibañez D, Mauceri D, Martin-Villalba A, Teleman AA. Brain-enriched RagB isoforms regulate the dynamics of mTORC1 activity through GATOR1 inhibition. Nat Cell Biol 2022; 24:1407-1421. [PMID: 36097071 PMCID: PMC9481464 DOI: 10.1038/s41556-022-00977-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 07/13/2022] [Indexed: 12/26/2022]
Abstract
Mechanistic target of rapamycin complex 1 (mTORC1) senses nutrient availability to appropriately regulate cellular anabolism and catabolism. During nutrient restriction, different organs in an animal do not respond equally, with vital organs being relatively spared. This raises the possibility that mTORC1 is differentially regulated in different cell types, yet little is known about this mechanistically. The Rag GTPases, RagA or RagB bound to RagC or RagD, tether mTORC1 in a nutrient-dependent manner to lysosomes where mTORC1 becomes activated. Although the RagA and B paralogues were assumed to be functionally equivalent, we find here that the RagB isoforms, which are highly expressed in neurons, impart mTORC1 with resistance to nutrient starvation by inhibiting the RagA/B GTPase-activating protein GATOR1. We further show that high expression of RagB isoforms is observed in some tumours, revealing an alternative strategy by which cancer cells can retain elevated mTORC1 upon low nutrient availability.
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Affiliation(s)
- Gianluca Figlia
- Signal Transduction in Cancer and Metabolism, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg University, Heidelberg, Germany
| | - Sandra Müller
- Signal Transduction in Cancer and Metabolism, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg University, Heidelberg, Germany
| | - Anna M Hagenston
- Department of Neurobiology, Interdisciplinary Center for Neurosciences (IZN), Heidelberg University, INF 366, Heidelberg, Germany
| | - Susanne Kleber
- Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Mykola Roiuk
- Signal Transduction in Cancer and Metabolism, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg University, Heidelberg, Germany
| | - Jan-Philipp Quast
- Signal Transduction in Cancer and Metabolism, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg University, Heidelberg, Germany
| | - Nora Ten Bosch
- Signal Transduction in Cancer and Metabolism, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Damian Carvajal Ibañez
- Heidelberg University, Heidelberg, Germany.,Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Daniela Mauceri
- Department of Neurobiology, Interdisciplinary Center for Neurosciences (IZN), Heidelberg University, INF 366, Heidelberg, Germany
| | - Ana Martin-Villalba
- Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Aurelio A Teleman
- Signal Transduction in Cancer and Metabolism, German Cancer Research Center (DKFZ), Heidelberg, Germany. .,Heidelberg University, Heidelberg, Germany.
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13
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mTORC1 controls Golgi architecture and vesicle secretion by phosphorylation of SCYL1. Nat Commun 2022; 13:4685. [PMID: 35948564 PMCID: PMC9365812 DOI: 10.1038/s41467-022-32487-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 07/30/2022] [Indexed: 12/04/2022] Open
Abstract
The protein kinase mechanistic target of rapamycin complex 1 (mTORC1) is a master regulator of cell growth and proliferation, supporting anabolic reactions and inhibiting catabolic pathways like autophagy. Its hyperactivation is a frequent event in cancer promoting tumor cell proliferation. Several intracellular membrane-associated mTORC1 pools have been identified, linking its function to distinct subcellular localizations. Here, we characterize the N-terminal kinase-like protein SCYL1 as a Golgi-localized target through which mTORC1 controls organelle distribution and extracellular vesicle secretion in breast cancer cells. Under growth conditions, SCYL1 is phosphorylated by mTORC1 on Ser754, supporting Golgi localization. Upon mTORC1 inhibition, Ser754 dephosphorylation leads to SCYL1 displacement to endosomes. Peripheral, dephosphorylated SCYL1 causes Golgi enlargement, redistribution of early and late endosomes and increased extracellular vesicle release. Thus, the mTORC1-controlled phosphorylation status of SCYL1 is an important determinant regulating subcellular distribution and function of endolysosomal compartments. It may also explain the pathophysiology underlying human genetic diseases such as CALFAN syndrome, which is caused by loss-of-function of SCYL1. mTORC1 is a master regulator of cell growth with well-known functions in inhibiting autophagic vesicle formation. Here, the authors show that mTORC1 also affects Golgi architecture and vesicle secretion by phosphorylating the scaffold protein SCYL1.
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14
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Fan J, Yuan Z, Burley SK, Libutti SK, Zheng XFS. Amino acids control blood glucose levels through mTOR signaling. Eur J Cell Biol 2022; 101:151240. [PMID: 35623230 PMCID: PMC10035058 DOI: 10.1016/j.ejcb.2022.151240] [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: 03/29/2022] [Revised: 05/15/2022] [Accepted: 05/16/2022] [Indexed: 12/12/2022] Open
Abstract
Amino Acids are not only major nutrient sources, but also serve as chemical signals to control cellular growth. Rab1A recently emerged as a key component in amino acid sensing and signaling to activate the mTOR complex1 (mTORC1). In a recently published study [1], we generated tamoxifen-inducible, conditional whole-body Rab1A knockout in adult mice. These mice are viable but develop hyperglycemia and glucose intolerance. Interestingly, Rab1A ablation selectively reduces insulin expression and pancreatic beta-cell population. Mechanistically, branched chain amino acids (BCAA), through the Rab1A-mTORC1 complex, promote the stability and nuclear localization of Pdx1, a master transcription factor that controls growth, function and identity of pancreatic beta-cells. These findings reveal a role and underlying mechanism by which amino acids control body's glucose level through a beta-cell specific function by the Rab1A-mTORC1-Pdx1 signaling axis, which has implications in both diabetes and cancer.
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Affiliation(s)
- Jialin Fan
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA
| | - Ziqiang Yuan
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Surgery, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA
| | - Stephen K Burley
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; RCSB Protein Data Bank and Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, 174 Frelinghuysen Road, Piscataway, NJ 08854, USA; Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 174 Frelinghuysen Road, Piscataway, NJ 08854, USA; RCSB Protein Data Bank, San Diego Supercomputer Center, University of California, La Jolla, 9500 Gilman Drive, San Diego, CA 92093, USA
| | - Steven K Libutti
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Surgery, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA
| | - X F Steven Zheng
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA.
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15
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Ong YT, Andrade J, Armbruster M, Shi C, Castro M, Costa ASH, Sugino T, Eelen G, Zimmermann B, Wilhelm K, Lim J, Watanabe S, Guenther S, Schneider A, Zanconato F, Kaulich M, Pan D, Braun T, Gerhardt H, Efeyan A, Carmeliet P, Piccolo S, Grosso AR, Potente M. A YAP/TAZ-TEAD signalling module links endothelial nutrient acquisition to angiogenic growth. Nat Metab 2022; 4:672-682. [PMID: 35726026 PMCID: PMC9236904 DOI: 10.1038/s42255-022-00584-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 05/13/2022] [Indexed: 12/13/2022]
Abstract
Angiogenesis, the process by which endothelial cells (ECs) form new blood vessels from existing ones, is intimately linked to the tissue's metabolic milieu and often occurs at nutrient-deficient sites. However, ECs rely on sufficient metabolic resources to support growth and proliferation. How endothelial nutrient acquisition and usage are regulated is unknown. Here we show that these processes are instructed by Yes-associated protein 1 (YAP)/WW domain-containing transcription regulator 1 (WWTR1/TAZ)-transcriptional enhanced associate domain (TEAD): a transcriptional module whose function is highly responsive to changes in the tissue environment. ECs lacking YAP/TAZ or their transcriptional partners, TEAD1, 2 and 4 fail to divide, resulting in stunted vascular growth in mice. Conversely, activation of TAZ, the more abundant paralogue in ECs, boosts proliferation, leading to vascular hyperplasia. We find that YAP/TAZ promote angiogenesis by fuelling nutrient-dependent mTORC1 signalling. By orchestrating the transcription of a repertoire of cell-surface transporters, including the large neutral amino acid transporter SLC7A5, YAP/TAZ-TEAD stimulate the import of amino acids and other essential nutrients, thereby enabling mTORC1 activation. Dissociating mTORC1 from these nutrient inputs-elicited by the loss of Rag GTPases-inhibits mTORC1 activity and prevents YAP/TAZ-dependent vascular growth. Together, these findings define a pivotal role for YAP/TAZ-TEAD in controlling endothelial mTORC1 and illustrate the essentiality of coordinated nutrient fluxes in the vasculature.
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Affiliation(s)
- Yu Ting Ong
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Jorge Andrade
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Berlin, Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Max Armbruster
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Chenyue Shi
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Marco Castro
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Berlin, Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Ana S H Costa
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Toshiya Sugino
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Guy Eelen
- Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, and Department of Oncology and Leuven Cancer Institute, VIB and KU Leuven, Leuven, Belgium
| | - Barbara Zimmermann
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Kerstin Wilhelm
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Joseph Lim
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Berlin, Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Shuichi Watanabe
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Stefan Guenther
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Andre Schneider
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Francesca Zanconato
- Department of Molecular Medicine, University of Padua School of Medicine, Padua, Italy
| | - Manuel Kaulich
- Institute of Biochemistry II, Goethe University, Frankfurt (Main), Germany
| | - Duojia Pan
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Thomas Braun
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Holger Gerhardt
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Berlin, Germany
- Integrative Vascular Biology Laboratory, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- DZHK (German Center for Cardiovascular Research), partner site Berlin, Berlin, Germany
- Vascular Patterning Laboratory, Center for Cancer Biology, VIB and KU Leuven, Leuven, Belgium
| | - Alejo Efeyan
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre, Madrid, Spain
| | - Peter Carmeliet
- Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, and Department of Oncology and Leuven Cancer Institute, VIB and KU Leuven, Leuven, Belgium
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
- Laboratory of Angiogenesis and Vascular Heterogeneity, Department of Biomedicine, Aarhus, Denmark
| | - Stefano Piccolo
- Department of Molecular Medicine, University of Padua School of Medicine, Padua, Italy
- IFOM-ETS, the AIRC Institute of Molecular Oncology, Milan, Italy
| | - Ana Rita Grosso
- UCIBIO - Applied Molecular Biosciences Unit, Department of Life Sciences, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Michael Potente
- Angiogenesis & Metabolism Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Berlin, Germany.
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.
- DZHK (German Center for Cardiovascular Research), partner site Berlin, Berlin, Germany.
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16
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Buel GR, Dang H, Asara JM, Blenis J, Mutvei AP. Prolonged deprivation of arginine or leucine induces PI3K/Akt-dependent reactivation of mTORC1. J Biol Chem 2022; 298:102030. [PMID: 35577075 PMCID: PMC9194872 DOI: 10.1016/j.jbc.2022.102030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 05/05/2022] [Accepted: 05/08/2022] [Indexed: 01/08/2023] Open
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17
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Ortega-Molina A, Efeyan A. From mouse genetics to targeting the Rag GTPase pathway. Mol Cell Oncol 2021; 8:1979370. [PMID: 34859142 DOI: 10.1080/23723556.2021.1979370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The identification of the Rag GTPases initiated the deciphering of the molecular puzzle of nutrient signaling to the mechanistic target of rapamycin (mTOR), and spurred interest in targeting this pathway to combat human disease. Recent mouse genetic studies have provided pathophysiological insight and pointed to potential indications for inhibitors of the Rag GTPase pathway.
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Affiliation(s)
- Ana Ortega-Molina
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Alejo Efeyan
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
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18
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Zhang S, Lin X, Hou Q, Hu Z, Wang Y, Wang Z. Regulation of mTORC1 by amino acids in mammalian cells: A general picture of recent advances. ACTA ACUST UNITED AC 2021; 7:1009-1023. [PMID: 34738031 PMCID: PMC8536509 DOI: 10.1016/j.aninu.2021.05.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 05/13/2021] [Accepted: 05/18/2021] [Indexed: 12/11/2022]
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) integrates various types of signal inputs, such as energy, growth factors, and amino acids to regulate cell growth and proliferation mainly through the 2 direct downstream targets, eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1) and ribosomal protein S6 kinase 1 (S6K1). Most of the signal arms upstream of mTORC1 including energy status, stress signals, and growth factors converge on the tuberous sclerosis complex (TSC) - Ras homologue enriched in brain (Rheb) axis. Amino acids, however, are distinct from other signals and modulate mTORC1 using a unique pathway. In recent years, the transmission mechanism of amino acid signals upstream of mTORC1 has been gradually elucidated, and some sensors or signal transmission pathways for individual amino acids have also been discovered. With the help of these findings, we propose a general picture of recent advances, which demonstrates that various amino acids from lysosomes, cytoplasm, and Golgi are sensed by their respective sensors. These signals converge on mTORC1 and form a huge and complicated signal network with multiple synergies, antagonisms, and feedback mechanisms.
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Affiliation(s)
- Shizhe Zhang
- Key Laboratory of Ruminant Nutrition and Physiology, College of Animal Science and Technology, Shandong Agricultural University, No. 61, Daizong Street, Tai'an, Shandong, China
| | - Xueyan Lin
- Key Laboratory of Ruminant Nutrition and Physiology, College of Animal Science and Technology, Shandong Agricultural University, No. 61, Daizong Street, Tai'an, Shandong, China
| | - Qiuling Hou
- Key Laboratory of Ruminant Nutrition and Physiology, College of Animal Science and Technology, Shandong Agricultural University, No. 61, Daizong Street, Tai'an, Shandong, China
| | - Zhiyong Hu
- Key Laboratory of Ruminant Nutrition and Physiology, College of Animal Science and Technology, Shandong Agricultural University, No. 61, Daizong Street, Tai'an, Shandong, China
| | - Yun Wang
- Key Laboratory of Ruminant Nutrition and Physiology, College of Animal Science and Technology, Shandong Agricultural University, No. 61, Daizong Street, Tai'an, Shandong, China
| | - Zhonghua Wang
- Key Laboratory of Ruminant Nutrition and Physiology, College of Animal Science and Technology, Shandong Agricultural University, No. 61, Daizong Street, Tai'an, Shandong, China
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19
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Fernandes SA, Demetriades C. The Multifaceted Role of Nutrient Sensing and mTORC1 Signaling in Physiology and Aging. FRONTIERS IN AGING 2021; 2:707372. [PMID: 35822019 PMCID: PMC9261424 DOI: 10.3389/fragi.2021.707372] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 08/12/2021] [Indexed: 01/10/2023]
Abstract
The mechanistic Target of Rapamycin (mTOR) is a growth-related kinase that, in the context of the mTOR complex 1 (mTORC1), touches upon most fundamental cellular processes. Consequently, its activity is a critical determinant for cellular and organismal physiology, while its dysregulation is commonly linked to human aging and age-related disease. Presumably the most important stimulus that regulates mTORC1 activity is nutrient sufficiency, whereby amino acids play a predominant role. In fact, mTORC1 functions as a molecular sensor for amino acids, linking the cellular demand to the nutritional supply. Notably, dietary restriction (DR), a nutritional regimen that has been shown to extend lifespan and improve healthspan in a broad spectrum of organisms, works via limiting nutrient uptake and changes in mTORC1 activity. Furthermore, pharmacological inhibition of mTORC1, using rapamycin or its analogs (rapalogs), can mimic the pro-longevity effects of DR. Conversely, nutritional amino acid overload has been tightly linked to aging and diseases, such as cancer, type 2 diabetes and obesity. Similar effects can also be recapitulated by mutations in upstream mTORC1 regulators, thus establishing a tight connection between mTORC1 signaling and aging. Although the role of growth factor signaling upstream of mTORC1 in aging has been investigated extensively, the involvement of signaling components participating in the nutrient sensing branch is less well understood. In this review, we provide a comprehensive overview of the molecular and cellular mechanisms that signal nutrient availability to mTORC1, and summarize the role that nutrients, nutrient sensors, and other components of the nutrient sensing machinery play in cellular and organismal aging.
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Affiliation(s)
- Stephanie A. Fernandes
- Max Planck Institute for Biology of Ageing (MPI-AGE), Cologne, Germany
- Cologne Graduate School for Ageing Research (CGA), Cologne, Germany
| | - Constantinos Demetriades
- Max Planck Institute for Biology of Ageing (MPI-AGE), Cologne, Germany
- Cologne Graduate School for Ageing Research (CGA), Cologne, Germany
- University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
- *Correspondence: Constantinos Demetriades,
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20
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Ortega-Molina A, Lebrero-Fernández C, Sanz A, Deleyto-Seldas N, Plata-Gómez AB, Menéndez C, Graña-Castro O, Caleiras E, Efeyan A. Inhibition of Rag GTPase signaling in mice suppresses B cell responses and lymphomagenesis with minimal detrimental trade-offs. Cell Rep 2021; 36:109372. [PMID: 34260908 PMCID: PMC8355512 DOI: 10.1016/j.celrep.2021.109372] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 05/12/2021] [Accepted: 06/18/2021] [Indexed: 12/19/2022] Open
Abstract
B lymphocytes are exquisitely sensitive to fluctuations in nutrient signaling by the Rag GTPases, and 15% of follicular lymphomas (FLs) harbor activating mutations in RRAGC. Hence, a potential therapeutic approach against malignant B cells is to inhibit Rag GTPase signaling, but because such inhibitors are still to be developed, efficacy and safety remain unknown. We generated knockin mice expressing a hypomorphic variant of RagC (Q119L); RagCQ119L/+ mice are viable and show attenuated nutrient signaling. B lymphocyte activation is cell-intrinsically impaired in RagCQ119L/+ mice, which also show significant suppression of genetically induced lymphomagenesis and autoimmunity. Surprisingly, no overt systemic trade-offs or phenotypic alterations caused by partial suppression of nutrient signaling are seen in other organs, and RagCQ119L/+ mice show normal longevity and normal age-dependent health decline. These results support the efficacy and safety of moderate inhibition of nutrient signaling against pathological B cells.
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Affiliation(s)
- Ana Ortega-Molina
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Melchor Fernandez Almagro 3, Madrid 28029, Spain.
| | - Cristina Lebrero-Fernández
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Melchor Fernandez Almagro 3, Madrid 28029, Spain
| | - Alba Sanz
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Melchor Fernandez Almagro 3, Madrid 28029, Spain
| | - Nerea Deleyto-Seldas
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Melchor Fernandez Almagro 3, Madrid 28029, Spain
| | - Ana Belén Plata-Gómez
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Melchor Fernandez Almagro 3, Madrid 28029, Spain
| | - Camino Menéndez
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Melchor Fernandez Almagro 3, Madrid 28029, Spain
| | - Osvaldo Graña-Castro
- Bioinformatics Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Eduardo Caleiras
- Histopathology Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Alejo Efeyan
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Melchor Fernandez Almagro 3, Madrid 28029, Spain.
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21
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Deleyto-Seldas N, Efeyan A. The mTOR-Autophagy Axis and the Control of Metabolism. Front Cell Dev Biol 2021; 9:655731. [PMID: 34277603 PMCID: PMC8281972 DOI: 10.3389/fcell.2021.655731] [Citation(s) in RCA: 119] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 05/19/2021] [Indexed: 12/12/2022] Open
Abstract
The mechanistic target of rapamycin (mTOR), master regulator of cellular metabolism, exists in two distinct complexes: mTOR complex 1 and mTOR complex 2 (mTORC1 and 2). MTORC1 is a master switch for most energetically onerous processes in the cell, driving cell growth and building cellular biomass in instances of nutrient sufficiency, and conversely, allowing autophagic recycling of cellular components upon nutrient limitation. The means by which the mTOR kinase blocks autophagy include direct inhibition of the early steps of the process, and the control of the lysosomal degradative capacity of the cell by inhibiting the transactivation of genes encoding structural, regulatory, and catalytic factors. Upon inhibition of mTOR, autophagic recycling of cellular components results in the reactivation of mTORC1; thus, autophagy lies both downstream and upstream of mTOR. The functional relationship between the mTOR pathway and autophagy involves complex regulatory loops that are significantly deciphered at the cellular level, but incompletely understood at the physiological level. Nevertheless, genetic evidence stemming from the use of engineered strains of mice has provided significant insight into the overlapping and complementary metabolic effects that physiological autophagy and the control of mTOR activity exert during fasting and nutrient overload.
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Affiliation(s)
- Nerea Deleyto-Seldas
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Center (CNIO), Madrid, Spain
| | - Alejo Efeyan
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Center (CNIO), Madrid, Spain
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22
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de la Calle Arregui C, Plata-Gómez AB, Deleyto-Seldas N, García F, Ortega-Molina A, Abril-Garrido J, Rodriguez E, Nemazanyy I, Tribouillard L, de Martino A, Caleiras E, Campos-Olivas R, Mulero F, Laplante M, Muñoz J, Pende M, Sabio G, Sabatini DM, Efeyan A. Limited survival and impaired hepatic fasting metabolism in mice with constitutive Rag GTPase signaling. Nat Commun 2021; 12:3660. [PMID: 34135321 PMCID: PMC8209044 DOI: 10.1038/s41467-021-23857-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 05/17/2021] [Indexed: 12/16/2022] Open
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) integrates cellular nutrient signaling and hormonal cues to control metabolism. We have previously shown that constitutive nutrient signaling to mTORC1 by means of genetic activation of RagA (expression of GTP-locked RagA, or RagAGTP) in mice resulted in a fatal energetic crisis at birth. Herein, we rescue neonatal lethality in RagAGTP mice and find morphometric and metabolic alterations that span glucose, lipid, ketone, bile acid and amino acid homeostasis in adults, and a median lifespan of nine months. Proteomic and metabolomic analyses of livers from RagAGTP mice reveal a failed metabolic adaptation to fasting due to a global impairment in PPARα transcriptional program. These metabolic defects are partially recapitulated by restricting activation of RagA to hepatocytes, and revert by pharmacological inhibition of mTORC1. Constitutive hepatic nutrient signaling does not cause hepatocellular damage and carcinomas, unlike genetic activation of growth factor signaling upstream of mTORC1. In summary, RagA signaling dictates dynamic responses to feeding-fasting cycles to tune metabolism so as to match the nutritional state.
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Affiliation(s)
- Celia de la Calle Arregui
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Ana Belén Plata-Gómez
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Nerea Deleyto-Seldas
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Fernando García
- Proteomics Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Ana Ortega-Molina
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Julio Abril-Garrido
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Elena Rodriguez
- Myocardial Pathophysiology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Ivan Nemazanyy
- Platform for Metabolic Analyses, Structure Fédérative de Recherche Necker, INSERM US24/CNRS UMS 3633, Paris, France
| | - Laura Tribouillard
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Faculté de Médecine, Université Laval, Québec, QC, Canada
- Centre de recherche sur le cancer de l'Université Laval, Université Laval, Québec, QC, Canada
| | - Alba de Martino
- Histopathology Unit. Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Eduardo Caleiras
- Histopathology Unit. Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Ramón Campos-Olivas
- Spectroscopy and NMR Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Francisca Mulero
- Molecular Imaging Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Mathieu Laplante
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Faculté de Médecine, Université Laval, Québec, QC, Canada
- Centre de recherche sur le cancer de l'Université Laval, Université Laval, Québec, QC, Canada
| | - Javier Muñoz
- Proteomics Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Mario Pende
- Institut Necker Enfants Malades, INSERM U1151, Université de Paris, Paris, France
| | - Guadalupe Sabio
- Myocardial Pathophysiology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - David M Sabatini
- Whitehead Institute for Biomedical Research, Nine Cambridge Center, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA
- David H. Koch Institute for Integrative Cancer Research at MIT, Cambridge, MA, USA
- Broad Institute, Seven Cambridge Center, Cambridge, MA, USA
- Howard Hughes Medical Institute, MIT, Cambridge, MA, USA
| | - Alejo Efeyan
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Madrid, Spain.
- Whitehead Institute for Biomedical Research, Nine Cambridge Center, Cambridge, MA, USA.
- Department of Biology, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA.
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23
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Mimura K, Sakamaki JI, Morishita H, Kawazu M, Mano H, Mizushima N. Genome-wide CRISPR screening reveals nucleotide synthesis negatively regulates autophagy. J Biol Chem 2021; 296:100780. [PMID: 34000301 PMCID: PMC8191307 DOI: 10.1016/j.jbc.2021.100780] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 04/12/2021] [Accepted: 05/12/2021] [Indexed: 02/06/2023] Open
Abstract
Macroautophagy (hereafter, autophagy) is a process that directs the degradation of cytoplasmic material in lysosomes. In addition to its homeostatic roles, autophagy undergoes dynamic positive and negative regulation in response to multiple forms of cellular stress, thus enabling the survival of cells. However, the precise mechanisms of autophagy regulation are not fully understood. To identify potential negative regulators of autophagy, we performed a genome-wide CRISPR screen using the quantitative autophagic flux reporter GFP-LC3-RFP. We identified phosphoribosylformylglycinamidine synthase, a component of the de novo purine synthesis pathway, as one such negative regulator of autophagy. Autophagy was activated in cells lacking phosphoribosylformylglycinamidine synthase or phosphoribosyl pyrophosphate amidotransferase, another de novo purine synthesis enzyme, or treated with methotrexate when exogenous levels of purines were insufficient. Purine starvation-induced autophagy activation was concomitant with mammalian target of rapamycin complex 1 (mTORC1) suppression and was profoundly suppressed in cells deficient for tuberous sclerosis complex 2, which negatively regulates mTORC1 through inhibition of Ras homolog enriched in brain, suggesting that purines regulate autophagy through the tuberous sclerosis complex-Ras homolog enriched in brain-mTORC1 signaling axis. Moreover, depletion of the pyrimidine synthesis enzymes carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase and dihydroorotate dehydrogenase activated autophagy as well, although mTORC1 activity was not altered by pyrimidine shortage. These results suggest a different mechanism of autophagy induction between purine and pyrimidine starvation. These findings provide novel insights into the regulation of autophagy by nucleotides and possibly the role of autophagy in nucleotide metabolism, leading to further developing anticancer strategies involving nucleotide synthesis and autophagy.
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Affiliation(s)
- Kaito Mimura
- Department of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Jun-Ichi Sakamaki
- Department of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hideaki Morishita
- Department of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Masahito Kawazu
- Division of Cellular Signaling, National Cancer Center Research Institute, Tokyo, Japan
| | - Hiroyuki Mano
- Division of Cellular Signaling, National Cancer Center Research Institute, Tokyo, Japan
| | - Noboru Mizushima
- Department of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
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24
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Zhang X, Wang X, Yuan Z, Radford SJ, Liu C, Libutti SK, Zheng XFS. Amino acids-Rab1A-mTORC1 signaling controls whole-body glucose homeostasis. Cell Rep 2021; 34:108830. [PMID: 33730578 PMCID: PMC8062038 DOI: 10.1016/j.celrep.2021.108830] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 12/28/2020] [Accepted: 02/16/2021] [Indexed: 12/17/2022] Open
Abstract
Rab1A is a small GTPase known for its role in vesicular trafficking. Recent evidence indicates that Rab1A is essential for amino acids (aas) sensing and signaling to regulate mTORC1 in normal and cancer cells. However, Rab1A's in vivo function in mammals is not known. Here, we report the generation of tamoxifen (TAM)-induced whole body Rab1A knockout (Rab1A-/-) in adult mice. Rab1A-/- mice are viable but become hyperglycemic and glucose intolerant due to impaired insulin transcription and β-cell proliferation and maintenance. Mechanistically, Rab1A mediates AA-mTORC1 signaling, particularly branched chain amino acids (BCAA), to regulate the stability and localization of the insulin transcription factor Pdx1. Collectively, these results reveal a physiological role of aa-Rab1A-mTORC1 signaling in the control of whole-body glucose homeostasis in mammals. Intriguingly, Rab1A expression is reduced in β-cells of type 2 diabetes (T2D) patients, which is correlated with loss of insulin expression, suggesting that Rab1A downregulation contributes to T2D progression.
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Affiliation(s)
- Xin Zhang
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA
| | - Xiaowen Wang
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA
| | - Ziqiang Yuan
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Surgery, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA
| | - Sarah J Radford
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA
| | - Chen Liu
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA
| | - Steven K Libutti
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Surgery, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA
| | - X F Steven Zheng
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA.
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25
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mTORC1 couples cyst(e)ine availability with GPX4 protein synthesis and ferroptosis regulation. Nat Commun 2021; 12:1589. [PMID: 33707434 PMCID: PMC7952727 DOI: 10.1038/s41467-021-21841-w] [Citation(s) in RCA: 319] [Impact Index Per Article: 106.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 02/16/2021] [Indexed: 12/16/2022] Open
Abstract
Glutathione peroxidase 4 (GPX4) utilizes glutathione (GSH) to detoxify lipid peroxidation and plays an essential role in inhibiting ferroptosis. As a selenoprotein, GPX4 protein synthesis is highly inefficient and energetically costly. How cells coordinate GPX4 synthesis with nutrient availability remains unclear. In this study, we perform integrated proteomic and functional analyses to reveal that SLC7A11-mediated cystine uptake promotes not only GSH synthesis, but also GPX4 protein synthesis. Mechanistically, we find that cyst(e)ine activates mechanistic/mammalian target of rapamycin complex 1 (mTORC1) and promotes GPX4 protein synthesis at least partly through the Rag-mTORC1-4EBP signaling axis. We show that pharmacologic inhibition of mTORC1 decreases GPX4 protein levels, sensitizes cancer cells to ferroptosis, and synergizes with ferroptosis inducers to suppress patient-derived xenograft tumor growth in vivo. Together, our results reveal a regulatory mechanism to coordinate GPX4 protein synthesis with cyst(e)ine availability and suggest using combinatorial therapy of mTORC1 inhibitors and ferroptosis inducers in cancer treatment.
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26
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Fritsch SD, Weichhart T. Metabolic and immunologic control of intestinal cell function by mTOR. Int Immunol 2020; 32:455-465. [PMID: 32140726 DOI: 10.1093/intimm/dxaa015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 02/28/2020] [Indexed: 02/06/2023] Open
Abstract
The intestinal epithelium is one of the most quickly dividing tissues in our body, combining the absorptive advantages of a single layer with the protection of a constantly renewing barrier. It is continuously exposed to nutrients and commensal bacteria as well as microbial and host-derived metabolites, but also to hazards such as pathogenic bacteria and toxins. These environmental cues are sensed by the mucosa and a vast repertory of immune cells, especially macrophages. A disruption of intestinal homeostasis in terms of barrier interruption can lead to inflammatory bowel diseases and colorectal cancer, and macrophages have an important role in restoring epithelial function following injury. The mammalian/mechanistic target of rapamycin (mTOR) signalling pathway senses environmental cues and integrates metabolic responses. It has emerged as an important regulator of intestinal functions in homeostasis and disease. In this review, we are going to discuss intestinal mTOR signalling and metabolic regulation in different intestinal cell populations with a special focus on immune cells and their actions on intestinal function.
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Affiliation(s)
- Stephanie D Fritsch
- Center of Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, Währinger Straße, Vienna, Austria
| | - Thomas Weichhart
- Center of Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, Währinger Straße, Vienna, Austria
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27
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Yang S, Zhang Y, Ting CY, Bettedi L, Kim K, Ghaniam E, Lilly MA. The Rag GTPase Regulates the Dynamic Behavior of TSC Downstream of Both Amino Acid and Growth Factor Restriction. Dev Cell 2020; 55:272-288.e5. [PMID: 32898476 PMCID: PMC7657977 DOI: 10.1016/j.devcel.2020.08.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/30/2020] [Accepted: 08/10/2020] [Indexed: 01/09/2023]
Abstract
The dysregulation of the metabolic regulator TOR complex I (TORC1) contributes to a wide array of human pathologies. Tuberous sclerosis complex (TSC) is a potent inhibitor of TORC1. Here, we demonstrate that the Rag GTPase acts in both the amino-acid-sensing and growth factor signaling pathways to control TORC1 activity through the regulation of TSC dynamics in HeLa cells and Drosophila. We find that TSC lysosomal-cytosolic exchange increases in response to both amino acid and growth factor restriction. Moreover, the rate of exchange mirrors TSC function, with depletions of the Rag GTPase blocking TSC lysosomal mobility and rescuing TORC1 activity. Finally, we show that the GATOR2 complex controls the phosphorylation of TSC2, which is essential for TSC exchange. Our data support the model that the amino acid and growth factor signaling pathways converge on the Rag GTPase to inhibit TORC1 activity through the regulation of TSC dynamics.
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Affiliation(s)
- Shu Yang
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yingbiao Zhang
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Chun-Yuan Ting
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lucia Bettedi
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kuikwon Kim
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Elena Ghaniam
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mary A Lilly
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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28
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Yao Y, Hong S, Ikeda T, Mori H, MacDougald OA, Nada S, Okada M, Inoki K. Amino Acids Enhance Polyubiquitination of Rheb and Its Binding to mTORC1 by Blocking Lysosomal ATXN3 Deubiquitinase Activity. Mol Cell 2020; 80:437-451.e6. [PMID: 33157014 PMCID: PMC7665239 DOI: 10.1016/j.molcel.2020.10.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 08/22/2020] [Accepted: 10/02/2020] [Indexed: 01/02/2023]
Abstract
Amino-acid-induced lysosomal mechanistic target of rapamycin complex 1 (mTORC1) localization through the Rag GTPases is a critical step for its activation by Rheb GTPase. However, how the mTORC1 interacts with Rheb on the lysosome remains elusive. We report that amino acids enhance the polyubiquitination of Rheb (Ub-Rheb), which shows a strong binding preference for mTORC1 and supports its activation, while the Ub-Rheb is subjected to subsequent degradation. Mechanistically, we identified ATXN3 as a Ub-Rheb deubiquitinase whose lysosomal localization is blocked by active Rag heterodimer in response to amino acid stimulation. Consistently, cells lacking functional Rag heterodimer on the lysosome accumulate Ub-Rheb, and blockade of its degradation instigates robust lysosomal mTORC1 localization and its activation without the Ragulator-Rag system. Thus, polyubiquitination of Rheb is an important post-translational modification, which facilitates the binding of mTORC1 to Rheb on the lysosome and is another crosstalk between the amino acid and growth factor signaling for mTORC1 activation.
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Affiliation(s)
- Yao Yao
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216, USA
| | - Sungki Hong
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216, USA
| | - Takayuki Ikeda
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216, USA; Department of Biochemistry, Kanazawa Medical University School of Medicine, 1-1 Daigaku, Uchinada, Kahoku-gun, Ishikawa 920-0293, Japan
| | - Hiroyuki Mori
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, 1137 E. Catherine St., Ann Arbor, MI 48109-5622, USA
| | - Ormond A MacDougald
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, 1137 E. Catherine St., Ann Arbor, MI 48109-5622, USA; Department of Internal Medicine, University of Michigan Medical School, 1500 East Medical Center Drive, Ann Arbor, MI 48109-5368, USA
| | - Shigeyuki Nada
- Department of Oncogene Research, the Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Masato Okada
- Department of Oncogene Research, the Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Ken Inoki
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216, USA; Department of Molecular and Integrative Physiology, University of Michigan Medical School, 1137 E. Catherine St., Ann Arbor, MI 48109-5622, USA; Department of Internal Medicine, University of Michigan Medical School, 1500 East Medical Center Drive, Ann Arbor, MI 48109-5368, USA.
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29
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Hoxhaj G, Locasale JW, Ben-Sahra I. A spoonful of DHAP keeps mTORC1 running on sugars. Nat Metab 2020; 2:801-802. [PMID: 32719540 DOI: 10.1038/s42255-020-0246-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Gerta Hoxhaj
- Children's Medical Center Research Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Jason W Locasale
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA.
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA.
| | - Issam Ben-Sahra
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL, USA.
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30
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Dumas SN, Lamming DW. Next Generation Strategies for Geroprotection via mTORC1 Inhibition. J Gerontol A Biol Sci Med Sci 2020; 75:14-23. [PMID: 30794726 DOI: 10.1093/gerona/glz056] [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: 12/10/2018] [Indexed: 01/10/2023] Open
Abstract
Inhibition of mTORC1 (mechanistic Target Of Rapamycin Complex 1) with the pharmaceutical rapamycin prolongs the lifespan and healthspan of model organisms including rodents, with evidence now emerging that rapamycin and its analogs may also have rejuvenative effects in dogs and humans. However, the side effects associated with long-term rapamycin treatment, many of which are due to inhibition of a second mTOR complex, mTORC2, have seemed to preclude the routine use of rapamycin as a therapy for age-related diseases. Here, we discuss recent findings suggesting that strong, chronic inhibition of both mTOR complexes may not be necessary to realize the geroprotective effects of rapamycin. Instead, modestly but specifically inhibiting mTORC1 via a variety of emerging techniques, including intermittent or transient treatment with rapamycin derivatives, or specific dietary regimens, may be sufficient to promote health and longevity with reduced side effects. We will also discuss prospects for the development of new molecules that, by harnessing the detailed molecular understanding of mTORC1 signaling developed over the last decade, will provide new routes to the selective inhibition of mTORC1. We conclude that therapies based on the selective inhibition of mTORC1 may soon permit the safer treatment of diseases of aging.
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Affiliation(s)
- Sabrina N Dumas
- William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin.,Department of Medicine, University of Wisconsin-Madison
| | - Dudley W Lamming
- William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin.,Department of Medicine, University of Wisconsin-Madison
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31
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Yazdankhah M, Shang P, Ghosh S, Hose S, Liu H, Weiss J, Fitting CS, Bhutto IA, Zigler JS, Qian J, Sahel JA, Sinha D, Stepicheva NA. Role of glia in optic nerve. Prog Retin Eye Res 2020; 81:100886. [PMID: 32771538 DOI: 10.1016/j.preteyeres.2020.100886] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/09/2020] [Accepted: 07/20/2020] [Indexed: 12/13/2022]
Abstract
Glial cells are critically important for maintenance of neuronal activity in the central nervous system (CNS), including the optic nerve (ON). However, the ON has several unique characteristics, such as an extremely high myelination level of retinal ganglion cell (RGC) axons throughout the length of the nerve (with virtually all fibers myelinated by 7 months of age in humans), lack of synapses and very narrow geometry. Moreover, the optic nerve head (ONH) - a region where the RGC axons exit the eye - represents an interesting area that is morphologically distinct in different species. In many cases of multiple sclerosis (demyelinating disease of the CNS) vision problems are the first manifestation of the disease, suggesting that RGCs and/or glia in the ON are more sensitive to pathological conditions than cells in other parts of the CNS. Here, we summarize current knowledge on glial organization and function in the ON, focusing on glial support of RGCs. We cover both well-established concepts on the important role of glial cells in ON health and new findings, including novel insights into mechanisms of remyelination, microglia/NG2 cell-cell interaction, astrocyte reactivity and the regulation of reactive astrogliosis by mitochondrial fragmentation in microglia.
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Affiliation(s)
- Meysam Yazdankhah
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Peng Shang
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Sayan Ghosh
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Stacey Hose
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Haitao Liu
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Joseph Weiss
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Christopher S Fitting
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Imran A Bhutto
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - J Samuel Zigler
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jiang Qian
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - José-Alain Sahel
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Institut de la Vision, INSERM, CNRS, Sorbonne Université, F-75012, Paris, France
| | - Debasish Sinha
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Nadezda A Stepicheva
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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32
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Do MH, Wang X, Zhang X, Chou C, Nixon BG, Capistrano KJ, Peng M, Efeyan A, Sabatini DM, Li MO. Nutrient mTORC1 signaling underpins regulatory T cell control of immune tolerance. J Exp Med 2020; 217:jem.20190848. [PMID: 31649036 PMCID: PMC7037250 DOI: 10.1084/jem.20190848] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 07/30/2019] [Accepted: 10/04/2019] [Indexed: 12/12/2022] Open
Abstract
Rag GTPase–dependent nutrient mTORC1 signaling plays a critical role in control of T reg cell suppression of autoimmunity and tumor immunity. These findings establish nutrients as a novel class of signaling molecule. Foxp3+ regulatory T (T reg) cells are pivotal regulators of immune tolerance, with T cell receptor (TCR)–driven activated T reg (aT reg) cells playing a central role; yet how TCR signaling propagates to control aT reg cell responses remains poorly understood. Here we show that TCR signaling induces expression of amino acid transporters, and renders amino acid–induced activation of mTORC1 in aT reg cells. T reg cell–specific ablation of the Rag family small GTPases RagA and RagB impairs amino acid–induced mTORC1 signaling, causing defective amino acid anabolism, reduced T reg cell proliferation, and a rampant autoimmune disorder similar in severity to that triggered by T reg cell–specific TCR deficiency. Notably, T reg cells in peripheral tissues, including tumors, are more sensitive to Rag GTPase–dependent nutrient sensing. Ablation of RagA alone impairs T reg cell accumulation in the tumor, resulting in enhanced antitumor immunity. Thus, nutrient mTORC1 signaling is an essential component of TCR-initiated T reg cell reprogramming, and Rag GTPase activities may be titrated to break tumor immune tolerance.
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Affiliation(s)
- Mytrang H Do
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY.,Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY
| | - Xinxin Wang
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY.,Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY
| | - Xian Zhang
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Chun Chou
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Briana G Nixon
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY.,Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY
| | - Kristelle J Capistrano
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Min Peng
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Alejo Efeyan
- Whitehead Institute for Biomedical Research, Cambridge, MA
| | - David M Sabatini
- Whitehead Institute for Biomedical Research, Cambridge, MA.,Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA.,David H. Koch Institute for Integrative Cancer Research at Massachusetts Institute of Technology, Cambridge, MA.,Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA
| | - Ming O Li
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY.,Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY
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33
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Frias MA, Mukhopadhyay S, Lehman E, Walasek A, Utter M, Menon D, Foster DA. Phosphatidic acid drives mTORC1 lysosomal translocation in the absence of amino acids. J Biol Chem 2020; 295:263-274. [PMID: 31767684 PMCID: PMC6952608 DOI: 10.1074/jbc.ra119.010892] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 11/14/2019] [Indexed: 01/30/2023] Open
Abstract
Mammalian target of rapamycin complex 1 (mTORC1) promotes cell growth and proliferation in response to nutrients and growth factors. Amino acids induce lysosomal translocation of mTORC1 via the Rag GTPases. Growth factors activate Ras homolog enriched in brain (Rheb), which in turn activates mTORC1 at the lysosome. Amino acids and growth factors also induce the phospholipase D (PLD)-phosphatidic acid (PA) pathway, required for mTORC1 signaling through mechanisms that are not fully understood. Here, using human and murine cell lines, along with immunofluorescence, confocal microscopy, endocytosis, PLD activity, and cell viability assays, we show that exogenously supplied PA vesicles deliver mTORC1 to the lysosome in the absence of amino acids, Rag GTPases, growth factors, and Rheb. Of note, pharmacological or genetic inhibition of endogenous PLD prevented mTORC1 lysosomal translocation. We observed that precancerous cells with constitutive Rheb activation through loss of tuberous sclerosis complex subunit 2 (TSC2) exploit the PLD-PA pathway and thereby sustain mTORC1 activation at the lysosome in the absence of amino acids. Our findings indicate that sequential inputs from amino acids and growth factors trigger PA production required for mTORC1 translocation and activation at the lysosome.
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Affiliation(s)
- Maria A Frias
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021; Clinical and Translational Master's Program, Clinical and Translational Science Center, Weill Cornell Medicine, New York, New York 10065.
| | - Suman Mukhopadhyay
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - Elyssa Lehman
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - Aleksandra Walasek
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - Matthew Utter
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - Deepak Menon
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - David A Foster
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021; Department of Pharmacology, Weill Cornell Medicine, New York, New York 10065.
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Amino Acids License Kinase mTORC1 Activity and Treg Cell Function via Small G Proteins Rag and Rheb. Immunity 2019; 51:1012-1027.e7. [PMID: 31668641 DOI: 10.1016/j.immuni.2019.10.001] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 09/17/2019] [Accepted: 09/27/2019] [Indexed: 12/17/2022]
Abstract
Regulatory T (Treg) cells are critical mediators of immune tolerance whose activity depends upon T cell receptor (TCR) and mTORC1 kinase signaling, but the mechanisms that dictate functional activation of these pathways are incompletely understood. Here, we showed that amino acids license Treg cell function by priming and sustaining TCR-induced mTORC1 activity. mTORC1 activation was induced by amino acids, especially arginine and leucine, accompanied by the dynamic lysosomal localization of the mTOR and Tsc complexes. Rag and Rheb GTPases were central regulators of amino acid-dependent mTORC1 activation in effector Treg (eTreg) cells. Mice bearing RagA-RagB- or Rheb1-Rheb2-deficient Treg cells developed a fatal autoimmune disease and had reduced eTreg cell accumulation and function. RagA-RagB regulated mitochondrial and lysosomal fitness, while Rheb1-Rheb2 enforced eTreg cell suppressive gene signature. Together, these findings reveal a crucial requirement of amino acid signaling for licensing and sustaining mTORC1 activation and functional programming of Treg cells.
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35
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Kadoya M, Sasai N. Negative Regulation of mTOR Signaling Restricts Cell Proliferation in the Floor Plate. Front Neurosci 2019; 13:1022. [PMID: 31607856 PMCID: PMC6773814 DOI: 10.3389/fnins.2019.01022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 09/09/2019] [Indexed: 01/07/2023] Open
Abstract
The neural tube is composed of a number of neural progenitors and postmitotic neurons distributed in a quantitatively and spatially precise manner. The floor plate, located in the ventral-most region of the neural tube, has a lot of unique characteristics, including a low cell proliferation rate. The mechanisms by which this region-specific proliferation rate is regulated remain elusive. Here we show that the activity of the mTOR signaling pathway, which regulates the proliferation of the neural progenitor cells, is significantly lower in the floor plate than in other domains of the embryonic neural tube. We identified the forkhead-type transcription factor FoxA2 as a negative regulator of mTOR signaling in the floor plate, and showed that FoxA2 transcriptionally induces the expression of the E3 ubiquitin ligase RNF152, which together with its substrate RagA, regulates cell proliferation via the mTOR pathway. Silencing of RNF152 led to the aberrant upregulation of the mTOR signal and aberrant cell division in the floor plate. Taken together, the present findings suggest that floor plate cell number is controlled by the negative regulation of mTOR signaling through the activity of FoxA2 and its downstream effector RNF152.
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Affiliation(s)
- Minori Kadoya
- Developmental Biomedical Science, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Japan
| | - Noriaki Sasai
- Developmental Biomedical Science, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Japan
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36
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Mihail SM, Wangzhou A, Kunjilwar KK, Moy JK, Dussor G, Walters ET, Price TJ. MNK-eIF4E signalling is a highly conserved mechanism for sensory neuron axonal plasticity: evidence from Aplysia californica. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190289. [PMID: 31544610 DOI: 10.1098/rstb.2019.0289] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Injury to sensory neurons causes an increase in the excitability of these cells leading to enhanced action potential generation and a lowering of spike threshold. This type of sensory neuron plasticity occurs across vertebrate and invertebrate species and has been linked to the development of both acute and persistent pain. Injury-induced plasticity in sensory neurons relies on localized changes in gene expression that occur at the level of mRNA translation. Many different translation regulation signalling events have been defined and these signalling events are thought to selectively target subsets of mRNAs. Recent evidence from mice suggests that the key signalling event for nociceptor plasticity is mitogen-activated protein kinase-interacting kinase (MNK) -mediated phosphorylation of eukaryotic translation initiation factor (eIF) 4E. To test the degree to which this is conserved in other species, we used a previously described sensory neuron plasticity model in Aplysia californica. We find, using a variety of pharmacological tools, that MNK signalling is crucial for axonal hyperexcitability in sensory neurons from Aplysia. We propose that MNK-eIF4E signalling is a core, evolutionarily conserved, signalling module that controls nociceptor plasticity. This finding has important implications for the therapeutic potential of this target, and it provides interesting clues about the evolutionary origins of mechanisms important for pain-related plasticity. This article is part of the Theo Murphy meeting issue 'Evolution of mechanisms and behaviour important for pain'.
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Affiliation(s)
- Sandra M Mihail
- Program in Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USA
| | - Andi Wangzhou
- Program in Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USA
| | - Kumud K Kunjilwar
- Department of Integrative Biology and Pharmacology, McGovern Medical School at UTHealth, 6431 Fannin Street, Houston, TX 77030, USA
| | - Jamie K Moy
- Program in Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USA
| | - Gregory Dussor
- Program in Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USA
| | - Edgar T Walters
- Department of Integrative Biology and Pharmacology, McGovern Medical School at UTHealth, 6431 Fannin Street, Houston, TX 77030, USA
| | - Theodore J Price
- Program in Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USA
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Ortega-Molina A, Deleyto-Seldas N, Carreras J, Sanz A, Lebrero-Fernández C, Menéndez C, Vandenberg A, Fernández-Ruiz B, Marín-Arraiza L, de la Calle Arregui C, Belén Plata-Gómez A, Caleiras E, de Martino A, Martínez-Martín N, Troulé K, Piñeiro-Yáñez E, Nakamura N, Araf S, Victora GD, Okosun J, Fitzgibbon J, Efeyan A. Oncogenic Rag GTPase signaling enhances B cell activation and drives follicular lymphoma sensitive to pharmacological inhibition of mTOR. Nat Metab 2019; 1:775-789. [PMID: 31579886 PMCID: PMC6774795 DOI: 10.1038/s42255-019-0098-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 07/12/2019] [Indexed: 12/13/2022]
Abstract
The humoral immune response demands that B cells undergo a sudden anabolic shift and high cellular nutrient levels which are required to sustain the subsequent proliferative burst. Follicular lymphoma (FL) originates from B cells that have participated in the humoral response, and 15% of FL samples harbor point, activating mutations in RRAGC, an essential activator of mTORC1 downstream of the sensing of cellular nutrients. The impact of recurrent RRAGC mutations in B cell function and lymphoma is unexplored. RRAGC mutations, targeted to the endogenous locus in mice, confer a partial insensitivity to nutrient deprivation, but strongly exacerbate B cell responses and accelerate lymphomagenesis, while creating a selective vulnerability to pharmacological inhibition of mTORC1. This moderate increase in nutrient signaling synergizes with paracrine cues from the supportive T cell microenvironment that activates B cells via the PI3K-Akt-mTORC1 axis. Hence, Rragc mutations sustain induced germinal centers and murine and human FL in the presence of decreased T cell help. Our results support a model in which activating mutations in the nutrient signaling pathway foster lymphomagenesis by corrupting a nutrient-dependent control over paracrine signals from the T cell microenvironment.
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Affiliation(s)
- Ana Ortega-Molina
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Nerea Deleyto-Seldas
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Joaquim Carreras
- Tokai University, School of Medicine, Department of Pathology. Isehara, Kanagawa, Japan
| | - Alba Sanz
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | | | - Camino Menéndez
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Andrew Vandenberg
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Beatriz Fernández-Ruiz
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Leyre Marín-Arraiza
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Celia de la Calle Arregui
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Ana Belén Plata-Gómez
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Eduardo Caleiras
- Histopathology Unit. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Alba de Martino
- Histopathology Unit. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | | | - Kevin Troulé
- Bioinformatics Unit. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Elena Piñeiro-Yáñez
- Bioinformatics Unit. Spanish National Cancer Research Center (CNIO). Madrid, Spain
| | - Naoya Nakamura
- Tokai University, School of Medicine, Department of Pathology. Isehara, Kanagawa, Japan
| | - Shamzah Araf
- Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, UK
| | - Gabriel D Victora
- Laboratory of Lymphocyte Dynamics, The Rockefeller University, New York, NY
| | - Jessica Okosun
- Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, UK
| | - Jude Fitzgibbon
- Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, UK
| | - Alejo Efeyan
- Metabolism and Cell Signaling Laboratory. Spanish National Cancer Research Center (CNIO). Madrid, Spain
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38
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Pertesi M, Ekdahl L, Palm A, Johnsson E, Järvstråt L, Wihlborg AK, Nilsson B. Essential genes shape cancer genomes through linear limitation of homozygous deletions. Commun Biol 2019; 2:262. [PMID: 31341961 PMCID: PMC6642121 DOI: 10.1038/s42003-019-0517-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 06/26/2019] [Indexed: 12/26/2022] Open
Abstract
The landscape of somatic acquired deletions in cancer cells is shaped by positive and negative selection. Recurrent deletions typically target tumor suppressor, leading to positive selection. Simultaneously, loss of a nearby essential gene can lead to negative selection, and introduce latent vulnerabilities specific to cancer cells. Here we show that, under basic assumptions on positive and negative selection, deletion limitation gives rise to a statistical pattern where the frequency of homozygous deletions decreases approximately linearly between the deletion target gene and the nearest essential genes. Using DNA copy number data from 9,744 human cancer specimens, we demonstrate that linear deletion limitation exists and exposes deletion-limiting genes for seven known deletion targets (CDKN2A, RB1, PTEN, MAP2K4, NF1, SMAD4, and LINC00290). Downstream analysis of pooled CRISPR/Cas9 data provide further evidence of essentiality. Our results provide further insight into how the deletion landscape is shaped and identify potentially targetable vulnerabilities.
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Affiliation(s)
- Maroulio Pertesi
- Hematology and Transfusion Medicine Department of Laboratory Medicine, BMC, SE-221 84 Lund, Sweden
| | - Ludvig Ekdahl
- Hematology and Transfusion Medicine Department of Laboratory Medicine, BMC, SE-221 84 Lund, Sweden
| | - Angelica Palm
- Hematology and Transfusion Medicine Department of Laboratory Medicine, BMC, SE-221 84 Lund, Sweden
| | - Ellinor Johnsson
- Hematology and Transfusion Medicine Department of Laboratory Medicine, BMC, SE-221 84 Lund, Sweden
| | - Linnea Järvstråt
- Hematology and Transfusion Medicine Department of Laboratory Medicine, BMC, SE-221 84 Lund, Sweden
| | - Anna-Karin Wihlborg
- Hematology and Transfusion Medicine Department of Laboratory Medicine, BMC, SE-221 84 Lund, Sweden
| | - Björn Nilsson
- Hematology and Transfusion Medicine Department of Laboratory Medicine, BMC, SE-221 84 Lund, Sweden
- Broad Institute, 415 Main Street, Cambridge, MA 02142 USA
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39
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Papadopoli D, Boulay K, Kazak L, Pollak M, Mallette FA, Topisirovic I, Hulea L. mTOR as a central regulator of lifespan and aging. F1000Res 2019; 8:F1000 Faculty Rev-998. [PMID: 31316753 PMCID: PMC6611156 DOI: 10.12688/f1000research.17196.1] [Citation(s) in RCA: 200] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/20/2019] [Indexed: 12/17/2022] Open
Abstract
The mammalian/mechanistic target of rapamycin (mTOR) is a key component of cellular metabolism that integrates nutrient sensing with cellular processes that fuel cell growth and proliferation. Although the involvement of the mTOR pathway in regulating life span and aging has been studied extensively in the last decade, the underpinning mechanisms remain elusive. In this review, we highlight the emerging insights that link mTOR to various processes related to aging, such as nutrient sensing, maintenance of proteostasis, autophagy, mitochondrial dysfunction, cellular senescence, and decline in stem cell function.
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Affiliation(s)
- David Papadopoli
- Gerald Bronfman Department of Oncology, McGill University, 5100 de Maisonneuve Blvd. West, Suite 720, Montréal, QC, H4A 3T2, Canada
- Lady Davis Institute, SMBD JGH, 3755 Chemin de la Côte-Sainte-Catherine, Montréal, QC, H3T 1E2, Canada
| | - Karine Boulay
- Lady Davis Institute, SMBD JGH, 3755 Chemin de la Côte-Sainte-Catherine, Montréal, QC, H3T 1E2, Canada
- Maisonneuve-Rosemont Hospital Research Centre, 5415 Assumption Blvd, Montréal, QC, H1T 2M4, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, CP 6128, Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada
| | - Lawrence Kazak
- Department of Biochemistry, McGill University, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada
- Goodman Cancer Research Centre, 1160 Pine Avenue West, Montréal, QC, H3A 1A3, Canada
| | - Michael Pollak
- Gerald Bronfman Department of Oncology, McGill University, 5100 de Maisonneuve Blvd. West, Suite 720, Montréal, QC, H4A 3T2, Canada
- Lady Davis Institute, SMBD JGH, 3755 Chemin de la Côte-Sainte-Catherine, Montréal, QC, H3T 1E2, Canada
- Goodman Cancer Research Centre, 1160 Pine Avenue West, Montréal, QC, H3A 1A3, Canada
- Department of Experimental Medicine, McGill University, 845 Sherbrooke Street West, Montréal, QC, H3A 0G4, Canada
| | - Frédérick A. Mallette
- Maisonneuve-Rosemont Hospital Research Centre, 5415 Assumption Blvd, Montréal, QC, H1T 2M4, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, CP 6128, Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada
- Département de Médecine, Université de Montréal, CP 6128, Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada
| | - Ivan Topisirovic
- Gerald Bronfman Department of Oncology, McGill University, 5100 de Maisonneuve Blvd. West, Suite 720, Montréal, QC, H4A 3T2, Canada
- Lady Davis Institute, SMBD JGH, 3755 Chemin de la Côte-Sainte-Catherine, Montréal, QC, H3T 1E2, Canada
- Department of Biochemistry, McGill University, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada
- Department of Experimental Medicine, McGill University, 845 Sherbrooke Street West, Montréal, QC, H3A 0G4, Canada
| | - Laura Hulea
- Maisonneuve-Rosemont Hospital Research Centre, 5415 Assumption Blvd, Montréal, QC, H1T 2M4, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, CP 6128, Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada
- Département de Médecine, Université de Montréal, CP 6128, Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada
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40
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Differences between Dorsal Root and Trigeminal Ganglion Nociceptors in Mice Revealed by Translational Profiling. J Neurosci 2019; 39:6829-6847. [PMID: 31253755 DOI: 10.1523/jneurosci.2663-18.2019] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 06/19/2019] [Accepted: 06/20/2019] [Indexed: 01/08/2023] Open
Abstract
Nociceptors located in the trigeminal ganglion (TG) and DRG are the primary sensors of damaging or potentially damaging stimuli for the head and body, respectively, and are key drivers of chronic pain states. While nociceptors in these two tissues show a high degree of functional similarity, there are important differences in their development lineages, their functional connections to the CNS, and recent genome-wide analyses of gene expression suggest that they possess some unique genomic signatures. Here, we used translating ribosome affinity purification to comprehensively characterize and compare mRNA translation in Scn10a-positive nociceptors in the TG and DRG of male and female mice. This unbiased method independently confirms several findings of differences between TG and DRG nociceptors described in the literature but also suggests preferential utilization of key signaling pathways. Most prominently, we provide evidence that translational efficiency in mechanistic target of rapamycin (mTOR)-related genes is higher in the TG compared with DRG, whereas several genes associated with the negative regulator of mTOR, AMP-activated protein kinase, have higher translational efficiency in DRG nociceptors. Using capsaicin as a sensitizing stimulus, we show that behavioral responses are greater in the TG region and this effect is completely reversible with mTOR inhibition. These findings have implications for the relative capacity of these nociceptors to be sensitized upon injury. Together, our data provide a comprehensive, comparative view of transcriptome and translatome activity in TG and DRG nociceptors that enhances our understanding of nociceptor biology.SIGNIFICANCE STATEMENT The DRG and trigeminal ganglion (TG) provide sensory information from the body and head, respectively. Nociceptors in these tissues are critical first neurons in the pain pathway. Injury to peripheral neurons in these tissues can cause chronic pain. Interestingly, clinical and preclinical findings support the conclusion that injury to TG neurons is more likely to cause chronic pain and chronic pain in the TG area is more intense and more difficult to treat. We used translating ribosome affinity purification technology to gain new insight into potential differences in the translatomes of DRG and TG neurons. Our findings demonstrate previously unrecognized differences between TG and DRG nociceptors that provide new insight into how injury may differentially drive plasticity states in nociceptors in these two tissues.
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41
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Gan L, Seki A, Shen K, Iyer H, Han K, Hayer A, Wollman R, Ge X, Lin JR, Dey G, Talbot WS, Meyer T. The lysosomal GPCR-like protein GPR137B regulates Rag and mTORC1 localization and activity. Nat Cell Biol 2019; 21:614-626. [PMID: 31036939 PMCID: PMC6649673 DOI: 10.1038/s41556-019-0321-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 03/27/2019] [Indexed: 12/13/2022]
Abstract
Cell growth is controlled by a lysosomal signaling complex containing Rag small GTPases and mTORC1 kinase. Here we carried out a microscopy-based genome-wide human siRNA screen and discovered a lysosome-localized G-protein coupled receptor (GPCR)-like protein, GPR137B, that interacts with Rag GTPases, increases Rag localization and activity, and thereby regulates mTORC1 translocation and activity. High GPR137B expression can recruit and activate mTORC1 in the absence of amino acids. Furthermore, GPR137B also regulates the dissociation of activated Rag from lysosomes, suggesting that GPR137B controls a cycle of Rag activation and dissociation from lysosomes. GPR137B knockout cells exhibited defective autophagy and an expanded lysosome compartment, similar to Rag knockout cells. Like zebrafish RagA mutants, GPR137B mutant zebrafish had upregulated TFEB target gene expression and an expanded lysosome compartment in microglia. Thus, GPR137B is a GPCR-like lysosomal regulatory protein that controls dynamic Rag and mTORC1 localization and activity as well as lysosome morphology.
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Affiliation(s)
- Lin Gan
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Akiko Seki
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Kimberle Shen
- Department of Developmental Biology, Stanford University, Stanford, CA, USA
| | - Harini Iyer
- Department of Developmental Biology, Stanford University, Stanford, CA, USA
| | - Kyuho Han
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Arnold Hayer
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Roy Wollman
- Department of Integrative Biology and Physiology and Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Xuecai Ge
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Jerry R Lin
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Gautam Dey
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - William S Talbot
- Department of Developmental Biology, Stanford University, Stanford, CA, USA
| | - Tobias Meyer
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA.
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42
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Megat S, Ray PR, Moy JK, Lou TF, Barragán-Iglesias P, Li Y, Pradhan G, Wanghzou A, Ahmad A, Burton MD, North RY, Dougherty PM, Khoutorsky A, Sonenberg N, Webster KR, Dussor G, Campbell ZT, Price TJ. Nociceptor Translational Profiling Reveals the Ragulator-Rag GTPase Complex as a Critical Generator of Neuropathic Pain. J Neurosci 2019; 39:393-411. [PMID: 30459229 PMCID: PMC6335757 DOI: 10.1523/jneurosci.2661-18.2018] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 11/05/2018] [Accepted: 11/14/2018] [Indexed: 12/11/2022] Open
Abstract
Nociceptors, sensory neurons in the DRG that detect damaging or potentially damaging stimuli, are key drivers of neuropathic pain. Injury to these neurons causes activation of translation regulation signaling, including the mechanistic target of rapamycin complex 1 (mTORC1) and mitogen-activated protein kinase interacting kinase (MNK) eukaryotic initiation factor (eIF) 4E pathways. This is a mechanism driving changes in excitability of nociceptors that is critical for the generation of chronic pain states; however, the mRNAs that are translated to lead to this plasticity have not been elucidated. To address this gap in knowledge, we used translating ribosome affinity purification in male and female mice to comprehensively characterize mRNA translation in Scn10a-positive nociceptors in chemotherapy-induced neuropathic pain (CIPN) caused by paclitaxel treatment. This unbiased method creates a new resource for the field, confirms many findings in the CIPN literature and also find extensive evidence for new target mechanisms that may cause CIPN. We provide evidence that an underlying mechanism of CIPN is sustained mTORC1 activation driven by MNK1-eIF4E signaling. RagA, a GTPase controlling mTORC1 activity, is identified as a novel target of MNK1-eIF4E signaling. This demonstrates a novel translation regulation signaling circuit wherein MNK1-eIF4E activity drives mTORC1 via control of RagA translation. CIPN and RagA translation are strongly attenuated by genetic ablation of eIF4E phosphorylation, MNK1 elimination or treatment with the MNK inhibitor eFT508. We identify a novel translational circuit for the genesis of neuropathic pain caused by chemotherapy with important implications for therapeutics.SIGNIFICANCE STATEMENT Neuropathic pain affects up to 10% of the population, but its underlying mechanisms are incompletely understood, leading to poor treatment outcomes. We used translating ribosome affinity purification technology to create a comprehensive translational profile of DRG nociceptors in naive mice and at the peak of neuropathic pain induced by paclitaxel treatment. We reveal new insight into how mechanistic target of rapamycin complex 1 is activated in neuropathic pain pointing to a key role of MNK1-eIF4E-mediated translation of a complex of mRNAs that control mechanistic target of rapamycin complex 1 signaling at the surface of the lysosome. We validate this finding using genetic and pharmacological techniques. Our work strongly suggests that MNK1-eIF4E signaling drives CIPN and that a drug in human clinical trials, eFT508, may be a new therapeutic for neuropathic pain.
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Affiliation(s)
- Salim Megat
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Pradipta R Ray
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Jamie K Moy
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
| | - Tzu-Fang Lou
- University of Texas at Dallas, Department of Biological Sciences, 800 Campbell Rd, Richardson, Texas, 75080
| | - Paulino Barragán-Iglesias
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Yan Li
- University of Texas M.D. Anderson Cancer Center, Department of Anesthesia and Pain Medicine, 1400 Holcombe Boulevard, Houston, TX 77030
| | - Grishma Pradhan
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Andi Wanghzou
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Ayesha Ahmad
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Michael D Burton
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Robert Y North
- University of Texas M.D. Anderson Cancer Center, Department of Anesthesia and Pain Medicine, 1400 Holcombe Boulevard, Houston, TX 77030
| | - Patrick M Dougherty
- University of Texas M.D. Anderson Cancer Center, Department of Anesthesia and Pain Medicine, 1400 Holcombe Boulevard, Houston, TX 77030
| | - Arkady Khoutorsky
- McGill University, Department of Anesthesia, 001 Boulevard Décarie C05.2000, Montréal, QC H4A 3J1, Canada
| | - Nahum Sonenberg
- McGill University, Goodman Cancer Research Center, Department of Biochemistry, 1160 Pine Ave W, Montreal, QC H3A 1A3, Canada, and
| | - Kevin R Webster
- eFFECTOR Therapeutics, 11180 Roselle St, San Diego, CA 92121
| | - Gregory Dussor
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Zachary T Campbell
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080,
- University of Texas at Dallas, Department of Biological Sciences, 800 Campbell Rd, Richardson, Texas, 75080
| | - Theodore J Price
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080,
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
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Sekiguchi T, Furuno N, Ishii T, Hirose E, Sekiguchi F, Wang Y, Kobayashi H. RagA, an mTORC1 activator, interacts with a hedgehog signaling protein, WDR35/IFT121. Genes Cells 2019; 24:151-161. [DOI: 10.1111/gtc.12663] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 12/12/2018] [Accepted: 12/13/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Takeshi Sekiguchi
- Department of Molecular Biology, Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Nobuaki Furuno
- Laboratory for Amphibian Biology, Graduate School of Science Hiroshima University Higashihiroshima Japan
| | - Takashi Ishii
- Department of BiochemistryFukuoka Dental College Fukuoka Japan
| | - Eiji Hirose
- Faculty of Health Promotional Sciences Tokoha University Kitaku, Shizuoka Japan
| | - Fumiko Sekiguchi
- Department of Molecular Biology, Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Yonggang Wang
- Department of Molecular Biology, Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Hideki Kobayashi
- Department of Human Nutrition, Faculty of Contemporary Life ScienceChugoku‐Gakuen University Okayama Japan
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Lamming DW, Bar-Peled L. Lysosome: The metabolic signaling hub. Traffic 2019; 20:27-38. [PMID: 30306667 PMCID: PMC6294686 DOI: 10.1111/tra.12617] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 09/17/2018] [Accepted: 10/07/2018] [Indexed: 12/27/2022]
Abstract
For the past five decades, the lysosome has been characterized as an unglamorous cellular recycling center. This notion has undergone a radical shift in the last 10 years, with new research revealing that this organelle serves as a major hub for metabolic signaling pathways. The discovery that master growth regulators, including the protein kinase mTOR (mechanistic target of rapamycin), make their home at the lysosomal surface has generated intense interest in the lysosome's key role in nutrient sensing and cellular homeostasis. The transcriptional networks required for lysosomal maintenance and function are just being unraveled and their connection to lysosome-based signaling pathways revealed. The catabolic and anabolic pathways that converge on the lysosome connect this organelle with multiple facets of cellular function; when these pathways are deregulated they underlie multiple human diseases, and promote cellular and organismal aging. Thus, understanding how lysosome-based signaling pathways function will not only illuminate the fascinating biology of this organelle but will also be critical in unlocking its therapeutic potentials.
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Affiliation(s)
- Dudley W. Lamming
- William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Liron Bar-Peled
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
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Hashimoto Y, Shirane M, Nakayama KI. TMEM55B contributes to lysosomal homeostasis and amino acid-induced mTORC1 activation. Genes Cells 2018; 23:418-434. [DOI: 10.1111/gtc.12583] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 03/13/2018] [Indexed: 01/28/2023]
Affiliation(s)
- Yutaka Hashimoto
- Department of Molecular and Cellular Biology; Medical Institute of Bioregulation; Kyushu University; Fukuoka Japan
| | - Michiko Shirane
- Department of Molecular and Cellular Biology; Medical Institute of Bioregulation; Kyushu University; Fukuoka Japan
- Department of Molecular Biology; Graduate School of Pharmaceutical Science; Nagoya City University; Nagoya Japan
| | - Keiichi I. Nakayama
- Department of Molecular and Cellular Biology; Medical Institute of Bioregulation; Kyushu University; Fukuoka Japan
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Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) coordinates cellular growth and metabolism with environmental inputs to ensure that cells grow only under favourable conditions. When active, mTORC1 stimulates biosynthetic pathways including protein, lipid and nucleotide synthesis and inhibits cellular catabolism through repression of the autophagic pathway, thereby promoting cell growth and proliferation. The recruitment of mTORC1 to the lysosomal surface has been shown to be essential for its activation. This finding has significantly enhanced our knowledge of mTORC1 regulation and has focused the attention of the field on the lysosome as a signalling hub which coordinates several homeostatic pathways. The intriguing localisation of mTORC1 to the cellular organelle that plays a crucial role in catabolism enables mTORC1 to feedback to autophagy and lysosomal biogenesis, thus leading mTORC1 to enact precise spatial and temporal control of cell growth. This review will cover the signalling interactions which take place on the surface of lysosomes and the cross-talk which exists between mTORC1 activity and lysosomal function.
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Affiliation(s)
- Yoana Rabanal-Ruiz
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE4 5PL, UK.
| | - Viktor I Korolchuk
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE4 5PL, UK.
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47
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Gosavi P, Houghton FJ, McMillan PJ, Hanssen E, Gleeson PA. The Golgi ribbon in mammalian cells negatively regulates autophagy by modulating mTOR activity. J Cell Sci 2018; 131:jcs.211987. [PMID: 29361552 DOI: 10.1242/jcs.211987] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/20/2017] [Indexed: 12/25/2022] Open
Abstract
In vertebrates, individual Golgi stacks are joined into a compact ribbon structure; however, the relevance of a ribbon structure has been elusive. Here, we exploit the finding that the membrane tether of the trans-Golgi network, GCC88 (encoded by GCC1), regulates the balance between Golgi mini-stacks and the Golgi ribbon. Loss of Golgi ribbons in stable cells overexpressing GCC88 resulted in compromised mechanistic target of rapamycin (mTOR) signaling and a dramatic increase in LC3-II-positive autophagosomes, whereas RNAi-mediated depletion of GCC88 restored the Golgi ribbon and reduced autophagy. mTOR was absent from dispersed Golgi mini-stacks whereas recruitment of mTOR to lysosomes was unaffected. We show that the Golgi ribbon is a site for localization and activation of mTOR, a process dependent on the ribbon structure. We demonstrate a strict temporal sequence of fragmentation of Golgi ribbon, loss of Golgi mTOR and subsequent increased autophagy. Golgi ribbon fragmentation has been reported in various neurodegenerative diseases and we demonstrate the potential relevance of our findings in neuronal cells using a model of neurodegeneration. Overall, this study highlights a role for the Golgi ribbon in pathways central to cellular homeostasis.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Prajakta Gosavi
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Fiona J Houghton
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Paul J McMillan
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia.,Biological Optical Microscopy Platform, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Eric Hanssen
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia.,Advanced Microscopy Facility, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Paul A Gleeson
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
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mTORC1 Inactivation Promotes Colitis-Induced Colorectal Cancer but Protects from APC Loss-Dependent Tumorigenesis. Cell Metab 2018; 27:118-135.e8. [PMID: 29275959 DOI: 10.1016/j.cmet.2017.11.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/21/2017] [Accepted: 11/15/2017] [Indexed: 01/17/2023]
Abstract
Dietary habits that can induce inflammatory bowel disease (IBD) are major colorectal cancer (CRC) risk factors, but mechanisms linking nutrients, IBD, and CRC are unknown. Using human data and mouse models, we show that mTORC1 inactivation-induced chromosomal instability impairs intestinal crypt proliferation and regeneration, CDK4/6 dependently. This triggers interleukin (IL)-6-associated reparative inflammation, inducing crypt hyper-proliferation, wound healing, and CRC. Blocking IL-6 signaling or reactivating mTORC1 reduces inflammation-induced CRC, so mTORC1 activation suppresses tumorigenesis in IBD. Conversely, mTORC1 inactivation is beneficial in APC loss-dependent CRC. Thus, IL-6 blockers or protein-rich-diet-linked mTORC1 activation may prevent IBD-associated CRC. However, abolishing mTORC1 can mitigate CRC in predisposed patients with APC mutations. Our work reveals mTORC1 oncogenic and tumor-suppressive roles in intestinal epithelium and avenues to optimized and personalized therapeutic regimens for CRC.
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49
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mTORC1 as the main gateway to autophagy. Essays Biochem 2017; 61:565-584. [PMID: 29233869 PMCID: PMC5869864 DOI: 10.1042/ebc20170027] [Citation(s) in RCA: 343] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 10/19/2017] [Accepted: 10/20/2017] [Indexed: 12/16/2022]
Abstract
Cells and organisms must coordinate their metabolic activity with changes in their environment to ensure their growth only when conditions are favourable. In order to maintain cellular homoeostasis, a tight regulation between the synthesis and degradation of cellular components is essential. At the epicentre of the cellular nutrient sensing is the mechanistic target of rapamycin complex 1 (mTORC1) which connects environmental cues, including nutrient and growth factor availability as well as stress, to metabolic processes in order to preserve cellular homoeostasis. Under nutrient-rich conditions mTORC1 promotes cell growth by stimulating biosynthetic pathways, including synthesis of proteins, lipids and nucleotides, and by inhibiting cellular catabolism through repression of the autophagic pathway. Its close signalling interplay with the energy sensor AMP-activated protein kinase (AMPK) dictates whether the cell actively favours anabolic or catabolic processes. Underlining the role of mTORC1 in the coordination of cellular metabolism, its deregulation is linked to numerous human diseases ranging from metabolic disorders to many cancers. Although mTORC1 can be modulated by a number of different inputs, amino acids represent primordial cues that cannot be compensated for by any other stimuli. The understanding of how amino acids signal to mTORC1 has increased considerably in the last years; however this area of research remains a hot topic in biomedical sciences. The current ideas and models proposed to explain the interrelationship between amino acid sensing, mTORC1 signalling and autophagy is the subject of the present review.
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50
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Cummings NE, Lamming DW. Regulation of metabolic health and aging by nutrient-sensitive signaling pathways. Mol Cell Endocrinol 2017; 455:13-22. [PMID: 27884780 PMCID: PMC5440210 DOI: 10.1016/j.mce.2016.11.014] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 10/07/2016] [Accepted: 11/19/2016] [Indexed: 01/20/2023]
Abstract
All organisms need to be capable of adapting to changes in the availability and composition of nutrients. Over 75 years ago, researchers discovered that a calorie restricted (CR) diet could significantly extend the lifespan of rats, and since then a CR diet has been shown to increase lifespan and healthspan in model organisms ranging from yeast to non-human primates. In this review, we discuss the effects of a CR diet on metabolism and healthspan, and highlight emerging evidence that suggests that dietary composition - the precise macronutrients that compose the diet - may be just as important as caloric content. In particular, we discuss recent evidence that suggests protein quality may influence metabolic health. Finally, we discuss key metabolic pathways which may influence the response to CR diets and altered macronutrient composition. Understanding the molecular mechanisms responsible for the effects of CR and dietary composition on health and longevity may allow the design of novel therapeutic approaches to age-related diseases.
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Affiliation(s)
- Nicole E Cummings
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA; William S. Middleton Memorial Veterans Hospital, Madison, WI, USA; Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Dudley W Lamming
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA; William S. Middleton Memorial Veterans Hospital, Madison, WI, USA; Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI, USA.
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