1
|
Böttcher B, Kienast SD, Leufken J, Eggers C, Sharma P, Leufken CM, Morgner B, Drexler HCA, Schulz D, Allert S, Jacobsen ID, Vylkova S, Leidel SA, Brunke S. A highly conserved tRNA modification contributes to C. albicans filamentation and virulence. Microbiol Spectr 2024; 12:e0425522. [PMID: 38587411 PMCID: PMC11064501 DOI: 10.1128/spectrum.04255-22] [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: 10/18/2022] [Accepted: 01/18/2024] [Indexed: 04/09/2024] Open
Abstract
tRNA modifications play important roles in maintaining translation accuracy in all domains of life. Disruptions in the tRNA modification machinery, especially of the anticodon stem loop, can be lethal for many bacteria and lead to a broad range of phenotypes in baker's yeast. Very little is known about the function of tRNA modifications in host-pathogen interactions, where rapidly changing environments and stresses require fast adaptations. We found that two closely related fungal pathogens of humans, the highly pathogenic Candida albicans and its much less pathogenic sister species, Candida dubliniensis, differ in the function of a tRNA-modifying enzyme. This enzyme, Hma1, exhibits species-specific effects on the ability of the two fungi to grow in the hypha morphology, which is central to their virulence potential. We show that Hma1 has tRNA-threonylcarbamoyladenosine dehydratase activity, and its deletion alters ribosome occupancy, especially at 37°C-the body temperature of the human host. A C. albicans HMA1 deletion mutant also shows defects in adhesion to and invasion into human epithelial cells and shows reduced virulence in a fungal infection model. This links tRNA modifications to host-induced filamentation and virulence of one of the most important fungal pathogens of humans.IMPORTANCEFungal infections are on the rise worldwide, and their global burden on human life and health is frequently underestimated. Among them, the human commensal and opportunistic pathogen, Candida albicans, is one of the major causative agents of severe infections. Its virulence is closely linked to its ability to change morphologies from yeasts to hyphae. Here, this ability is linked-to our knowledge for the first time-to modifications of tRNA and translational efficiency. One tRNA-modifying enzyme, Hma1, plays a specific role in C. albicans and its ability to invade the host. This adds a so-far unknown layer of regulation to the fungal virulence program and offers new potential therapeutic targets to fight fungal infections.
Collapse
Affiliation(s)
- Bettina Böttcher
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Septomics Research Center, Friedrich Schiller University and Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Sandra D. Kienast
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Johannes Leufken
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Cristian Eggers
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Puneet Sharma
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Christine M. Leufken
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Bianka Morgner
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Hannes C. A. Drexler
- Bioanalytical Mass Spectrometry Unit, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Daniela Schulz
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Stefanie Allert
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Ilse D. Jacobsen
- Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Slavena Vylkova
- Septomics Research Center, Friedrich Schiller University and Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Sebastian A. Leidel
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| |
Collapse
|
2
|
Umargamwala R, Manning J, Dorstyn L, Denton D, Kumar S. Understanding Developmental Cell Death Using Drosophila as a Model System. Cells 2024; 13:347. [PMID: 38391960 PMCID: PMC10886741 DOI: 10.3390/cells13040347] [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: 01/23/2024] [Revised: 02/09/2024] [Accepted: 02/13/2024] [Indexed: 02/24/2024] Open
Abstract
Cell death plays an essential function in organismal development, wellbeing, and ageing. Many types of cell deaths have been described in the past 30 years. Among these, apoptosis remains the most conserved type of cell death in metazoans and the most common mechanism for deleting unwanted cells. Other types of cell deaths that often play roles in specific contexts or upon pathological insults can be classed under variant forms of cell death and programmed necrosis. Studies in Drosophila have contributed significantly to the understanding and regulation of apoptosis pathways. In addition to this, Drosophila has also served as an essential model to study the genetic basis of autophagy-dependent cell death (ADCD) and other relatively rare types of context-dependent cell deaths. Here, we summarise what is known about apoptosis, ADCD, and other context-specific variant cell death pathways in Drosophila, with a focus on developmental cell death.
Collapse
Affiliation(s)
- Ruchi Umargamwala
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA 5001, Australia; (J.M.); (L.D.)
| | - Jantina Manning
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA 5001, Australia; (J.M.); (L.D.)
| | - Loretta Dorstyn
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA 5001, Australia; (J.M.); (L.D.)
| | - Donna Denton
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA 5001, Australia; (J.M.); (L.D.)
| | - Sharad Kumar
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA 5001, Australia; (J.M.); (L.D.)
- Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA 5005, Australia
| |
Collapse
|
3
|
Huang K, Liu X, Zhang Z, Wang T, Xu H, Li Q, Jia Y, Huang L, Kim P, Zhou X. AgeAnnoMO: a knowledgebase of multi-omics annotation for animal aging. Nucleic Acids Res 2024; 52:D822-D834. [PMID: 37850649 PMCID: PMC10767957 DOI: 10.1093/nar/gkad884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/16/2023] [Accepted: 10/02/2023] [Indexed: 10/19/2023] Open
Abstract
Aging entails gradual functional decline influenced by interconnected factors. Multiple hallmarks proposed as common and conserved underlying denominators of aging on the molecular, cellular and systemic levels across multiple species. Thus, understanding the function of aging hallmarks and their relationships across species can facilitate the translation of anti-aging drug development from model organisms to humans. Here, we built AgeAnnoMO (https://relab.xidian.edu.cn/AgeAnnoMO/#/), a knowledgebase of multi-omics annotation for animal aging. AgeAnnoMO encompasses an extensive collection of 136 datasets from eight modalities, encompassing 8596 samples from 50 representative species, making it a comprehensive resource for aging and longevity research. AgeAnnoMO characterizes multiple aging regulators across species via multi-omics data, comprehensively annotating aging-related genes, proteins, metabolites, mitochondrial genes, microbiotas and age-specific TCR and BCR sequences tied to aging hallmarks for these species and tissues. AgeAnnoMO not only facilitates a deeper and more generalizable understanding of aging mechanisms, but also provides potential insights of the specificity across tissues and species in aging process, which is important to develop the effective anti-aging interventions for diverse populations. We anticipate that AgeAnnoMO will provide a valuable resource for comprehending and integrating the conserved driving hallmarks in aging biology and identifying the targetable biomarkers for aging research.
Collapse
Affiliation(s)
- Kexin Huang
- The Center of Gerontology and Geriatrics and West China Biomedical Big Data Centre, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, PR China
- Center for Computational Systems Medicine, School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Med-X Center for Informatics, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Xi Liu
- School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, PR China
| | - Zhaocan Zhang
- School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, PR China
| | - Tiangang Wang
- School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, PR China
| | - Haixia Xu
- The Center of Gerontology and Geriatrics and West China Biomedical Big Data Centre, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Qingxuan Li
- School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, PR China
| | - Yuhao Jia
- School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, PR China
| | - Liyu Huang
- School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, PR China
| | - Pora Kim
- Center for Computational Systems Medicine, School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Xiaobo Zhou
- Center for Computational Systems Medicine, School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
- School of Dentistry, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| |
Collapse
|
4
|
Privalova V, Labecka AM, Szlachcic E, Sikorska A, Czarnoleski M. Systemic changes in cell size throughout the body of Drosophila melanogaster associated with mutations in molecular cell cycle regulators. Sci Rep 2023; 13:7565. [PMID: 37160985 PMCID: PMC10169805 DOI: 10.1038/s41598-023-34674-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 05/05/2023] [Indexed: 05/11/2023] Open
Abstract
Along with different life strategies, organisms have evolved dramatic cellular composition differences. Understanding the molecular basis and fitness effects of these differences is key to elucidating the fundamental characteristics of life. TOR/insulin pathways are key regulators of cell size, but whether their activity determines cell size in a systemic or tissue-specific manner awaits exploration. To that end, we measured cells in four tissues in genetically modified Drosophila melanogaster (rictorΔ2 and Mnt1) and corresponding controls. While rictorΔ2 flies lacked the Rictor protein in TOR complex 2, downregulating the functions of this element in TOR/insulin pathways, Mnt1 flies lacked the transcriptional regulator protein Mnt, weakening the suppression of downstream signalling from TOR/insulin pathways. rictorΔ2 flies had smaller epidermal (leg and wing) and ommatidial cells and Mnt1 flies had larger cells in these tissues than the controls. Females had consistently larger cells than males in the three tissue types. In contrast, dorsal longitudinal flight muscle cells (measured only in males) were not altered by mutations. We suggest that mutations in cell cycle control pathways drive the evolution of systemic changes in cell size throughout the body, but additional mechanisms shape the cellular composition of some tissues independent of these mutations.
Collapse
Affiliation(s)
- Valeriya Privalova
- Life History Evolution Group, Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Anna Maria Labecka
- Life History Evolution Group, Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Ewa Szlachcic
- Life History Evolution Group, Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Anna Sikorska
- Life History Evolution Group, Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Marcin Czarnoleski
- Life History Evolution Group, Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland.
| |
Collapse
|
5
|
Xiong F, Tian J, Wei Z, Deng K, Li Y, Zhang Y. Suppression of the target of rapamycin kinase accelerates tomato fruit ripening through reprogramming the transcription profile and promoting ethylene biosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:2603-2619. [PMID: 36786543 DOI: 10.1093/jxb/erad056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 02/11/2023] [Indexed: 06/06/2023]
Abstract
Tomato fruit ripening is a unique process of nutritional and energy metabolism. Target of rapamycin (TOR), a conserved serine/threonine protein kinase in eukaryotes, controls cell growth and metabolism by integrating nutrient, energy, and hormone signals. However, it remains unclear whether TOR participates in the modulation of tomato fruit ripening. Here, we showed that the manipulation of SlTOR by chemical or genetic methods greatly alters the process of tomato fruit maturation. Expression pattern analysis revealed that the transcripts of SlTOR declined as fruit ripening progressed. Moreover, suppression of SlTOR by TOR inhibitor AZD8055 or knock down of its transcripts by inducible RNA interference, accelerated fruit ripening, and led to overall effects on fruit maturity, including changes in colour and metabolism, fruit softening, and expression of ripening-related genes. Genome-wide transcription analysis indicated that silencing SlTOR reprogrammed the transcript profile associated with ripening, including cell wall and phytohormone pathways, elevated the expression of ethylene biosynthetic genes, and further promoted ethylene production. In contrast, the ethylene action inhibitor 1-MCP efficiently blocked fruit maturation, even following SlTOR inhibition. These results suggest that accelerated fruit ripening caused by SlTOR inhibition depends on ethylene, and that SlTOR may function as a regulator in ethylene metabolism.
Collapse
Affiliation(s)
- Fangjie Xiong
- Biotechnology Research Center, Southwest University, Chongqing 400716, China
- School of Life Sciences, Chongqing University, Chongqing 401331, China
| | - Jianwei Tian
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Zhenzhen Wei
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Kexuan Deng
- School of Life Sciences, Chongqing University, Chongqing 401331, China
- College of Agronomy and Biotechnology, Southwest University, Chongqing 400716, China
| | - Yan Li
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Yanjie Zhang
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| |
Collapse
|
6
|
TORC1 Signaling in Fungi: From Yeasts to Filamentous Fungi. Microorganisms 2023; 11:microorganisms11010218. [PMID: 36677510 PMCID: PMC9864104 DOI: 10.3390/microorganisms11010218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 01/18/2023] Open
Abstract
Target of rapamycin complex 1 (TORC1) is an important regulator of various signaling pathways. It can control cell growth and development by integrating multiple signals from amino acids, glucose, phosphate, growth factors, pressure, oxidation, and so on. In recent years, it has been reported that TORC1 is of great significance in regulating cytotoxicity, morphology, protein synthesis and degradation, nutrient absorption, and metabolism. In this review, we mainly discuss the upstream and downstream signaling pathways of TORC1 to reveal its role in fungi.
Collapse
|
7
|
Xiang L, Disasa D, Liu Y, Fujii R, Yang M, Wu E, Matsuura A, Qi J. Gentirigeoside B from Gentiana rigescens Franch Prolongs Yeast Lifespan via Inhibition of TORC1/Sch9/Rim15/Msn Signaling Pathway and Modification of Oxidative Stress and Autophagy. Antioxidants (Basel) 2022; 11:antiox11122373. [PMID: 36552582 PMCID: PMC9774393 DOI: 10.3390/antiox11122373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/26/2022] [Accepted: 11/29/2022] [Indexed: 12/03/2022] Open
Abstract
Gentirigeoside B (GTS B) is a dammaren-type triterpenoid glycoside isolated from G. rigescens Franch, a traditional Chinese medicinal plant. In the present study, the evaluation of the anti-aging effect and action mechanism analysis for this compound were conducted. GTS B significantly extended the replicative lifespan and chronological lifespan of yeast at doses of 1, 3 and 10 μM. Furthermore, the inhibition of Sch9 and activity increase of Rim15, Msn2 proteins which located downstream of TORC1 signaling pathway were observed after treatment with GTS B. Additionally, autophagy of yeast was increased. In addition, GTS B significantly improved survival rate of yeast under oxidative stress conditions as well as reduced the levels of ROS and MDA. It also increased the gene expression and enzymatic activities of key anti-oxidative enzymes such as Sod1, Sod2, Cat and Gpx. However, this molecule failed to extend the lifespan of yeast mutants such as ∆cat, ∆gpx, ∆sod1, ∆sod2, ∆skn7 and ∆uth1. These results suggested that GTS B exerts an anti-aging effect via inhibition of the TORC1/Sch9/Rim15/Msn signaling pathway and enhancement of autophagy. Therefore, GTS B may be a promising candidate molecule to develop leading compounds for the treatment of aging and age-related disorders.
Collapse
Affiliation(s)
- Lan Xiang
- College of Pharmaceutical Science, Zhejiang University, 866 Yu Hang Road, Hangzhou 310058, China
- Correspondence: (L.X.); (J.Q.); Tel.: +86-571-88208627 (J.Q.)
| | - Dejene Disasa
- College of Pharmaceutical Science, Zhejiang University, 866 Yu Hang Road, Hangzhou 310058, China
| | - Yanan Liu
- College of Pharmaceutical Science, Zhejiang University, 866 Yu Hang Road, Hangzhou 310058, China
| | - Rui Fujii
- Department of Biology, Graduate School of Science, Chiba University, Chiba 263-8522, Japan
| | - Mengya Yang
- College of Pharmaceutical Science, Zhejiang University, 866 Yu Hang Road, Hangzhou 310058, China
| | - Enchan Wu
- College of Pharmaceutical Science, Zhejiang University, 866 Yu Hang Road, Hangzhou 310058, China
| | - Akira Matsuura
- Department of Biology, Graduate School of Science, Chiba University, Chiba 263-8522, Japan
| | - Jianhua Qi
- College of Pharmaceutical Science, Zhejiang University, 866 Yu Hang Road, Hangzhou 310058, China
- Correspondence: (L.X.); (J.Q.); Tel.: +86-571-88208627 (J.Q.)
| |
Collapse
|
8
|
Curative activity of KCl treatments to control citrus sour rot. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
9
|
Cardiovascular protection associated with cilostazol, colchicine and target of rapamycin inhibitors. J Cardiovasc Pharmacol 2022; 80:31-43. [PMID: 35384911 DOI: 10.1097/fjc.0000000000001276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 03/06/2022] [Indexed: 11/26/2022]
Abstract
ABSTRACT An alteration in extracellular matrix production by vascular smooth muscle cells is a crucial event in the pathogenesis of vascular diseases such as aging-related, atherosclerosis and allograft vasculopathy. The human target of rapamycin (TOR) is involved in the synthesis of extracellular matrix by vascular smooth muscle cells. TOR inhibitors reduce arterial stiffness, blood pressure, and left ventricle hypertrophy and decrease cardiovascular risk in kidney graft recipients and patients with coronary artery disease and heart allograft vasculopathy. Other drugs that modulate extracellular matrix production such as cilostazol and colchicine have also demonstrated a beneficial cardiovascular effect. Clinical studies have consistently shown that cilostazol confers cardiovascular protection in peripheral vascular disease, coronary artery disease, and cerebrovascular disease. In patients with type 2 diabetes, cilostazol prevents the progression of subclinical coronary atherosclerosis. Colchicine reduces arterial stiffness in patients with Familial Mediterranean Fever and patients with coronary artery disease. Pathophysiological mechanisms underlying the cardioprotective effect of these drugs may be related to interactions between the cytoskeleton, TOR signaling and cyclic AMP synthesis that remain to be fully elucidated. Adult vascular smooth muscle cells exhibit a contractile phenotype and produce little extracellular matrix. Conditions that upregulate extracellular matrix synthesis induce a phenotypic switch toward a synthetic phenotype. TOR inhibition with rapamycin reduces extracellular matrix production by promoting the change to the contractile phenotype. Cilostazol increases the cytosolic level of cyclic AMP, which in turn leads to a reduction in extracellular matrix synthesis. Colchicine is a microtubule-destabilizing agent that may enhance the synthesis of cyclic AMP.
Collapse
|
10
|
Nicolson GL, Ferreira de Mattos G, Ash M, Settineri R, Escribá PV. Fundamentals of Membrane Lipid Replacement: A Natural Medicine Approach to Repairing Cellular Membranes and Reducing Fatigue, Pain, and Other Symptoms While Restoring Function in Chronic Illnesses and Aging. MEMBRANES 2021; 11:944. [PMID: 34940446 PMCID: PMC8707623 DOI: 10.3390/membranes11120944] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 11/23/2021] [Accepted: 11/23/2021] [Indexed: 12/14/2022]
Abstract
Membrane Lipid Replacement (MLR) uses natural membrane lipid supplements to safely replace damaged, oxidized lipids in membranes in order to restore membrane function, decrease symptoms and improve health. Oral MLR supplements contain mixtures of cell membrane glycerolphospholipids, fatty acids, and other lipids, and can be used to replace and remove damaged cellular and intracellular membrane lipids. Membrane injury, caused mainly by oxidative damage, occurs in essentially all chronic and acute medical conditions, including cancer and degenerative diseases, and in normal processes, such as aging and development. After ingestion, the protected MLR glycerolphospholipids and other lipids are dispersed, absorbed, and internalized in the small intestines, where they can be partitioned into circulating lipoproteins, globules, liposomes, micelles, membranes, and other carriers and transported in the lymphatics and blood circulation to tissues and cellular sites where they are taken in by cells and partitioned into various cellular membranes. Once inside cells, the glycerolphospholipids and other lipids are transferred to various intracellular membranes by lipid carriers, globules, liposomes, chylomicrons, or by direct membrane-membrane interactions. The entire process appears to be driven by 'bulk flow' or mass action principles, where surplus concentrations of replacement lipids can stimulate the natural exchange and removal of damaged membrane lipids while the replacement lipids undergo further enzymatic alterations. Clinical studies have demonstrated the advantages of MLR in restoring membrane and organelle function and reducing fatigue, pain, and other symptoms in chronic illness and aging patients.
Collapse
Affiliation(s)
- Garth L. Nicolson
- Department of Molecular Pathology, The Institute for Molecular Medicine, Huntington Beach, CA 92647, USA
| | - Gonzalo Ferreira de Mattos
- Laboratory of Ion Channels, Biological Membranes and Cell Signaling, Department of Biophysics, Facultad de Medicina, Universidad de la República, Montevideo 11600, Uruguay;
| | - Michael Ash
- Clinical Education, Newton Abbot, Devon TQ12 4SG, UK;
| | | | - Pablo V. Escribá
- Laboratory of Molecular Cell Biomedicine, University of the Balearic Islands, 07122 Palma de Mallorca, Spain;
| |
Collapse
|
11
|
Escobar-Niño A, Morano Bermejo IM, Carrasco Reinado R, Fernandez-Acero FJ. Deciphering the Dynamics of Signaling Cascades and Virulence Factors of B. cinerea during Tomato Cell Wall Degradation. Microorganisms 2021; 9:microorganisms9091837. [PMID: 34576732 PMCID: PMC8466851 DOI: 10.3390/microorganisms9091837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/11/2021] [Accepted: 08/24/2021] [Indexed: 11/30/2022] Open
Abstract
The ascomycete Botrytis cinerea is one of the most relevant plant pathogenic fungi, affecting fruits, flowers, and greenhouse-grown crops. The infection strategy used by the fungus comprises a magnificent set of tools to penetrate and overcome plant defenses. In this context, the plant-pathogen communication through membrane receptors and signal transduction cascades is essential to trigger specific routes and the final success of the infection. In previous reports, proteomics approaches to B. cinerea signal transduction cascades changes in response to different carbon source and plant-based elicitors have been performed. Analyzing the secretome, membranome, phosphoproteome, and the phosphomembranome. Moreover, phenotypic changes in fungal biology was analyzed, specifically toxin production. To obtain the whole picture of the process and reveal the network from a system biology approach, this proteomic information has been merged with the phenotypic characterization, to be analyzed using several bioinformatics algorithms (GO, STRING, MCODE) in order to unravel key points in the signal transduction regulation crucial to overcome plant defenses, as well as new virulence/pathogenicity factors that could be used as therapeutic targets in the control of the gray mold rot disease. A total of 1721 and 663 exclusive or overexpressed proteins were identified under glucose (GLU) and deproteinized tomato cell walls (TCW), summarizing all of the protein identifications under phenotypic characterized stages. Under GO analysis, there are more biological process and molecular functions described in GLU, highlighting the increase in signaling related categories. These results agree with the high number of total identified proteins in GLU, probably indicating a more varied and active metabolism of the fungus. When analyzing only GO annotations related with signal transduction, it was revealed that there were proteins related to TOR signaling, the phosphorelay signal transduction system, and inositol lipid-mediated signaling, only under GLU conditions. On the contrary, calcium-mediated signaling GO annotation is only present between the proteins identified under TCW conditions. To establish a potential relationship between expressed proteins, cluster analyses showed 41 and 14 clusters under GLU and TCW conditions, confirming an increase in biological activity in GLU, where we identified a larger number of clusters related to transcription, translation, and cell division, between others. From these analyses, clusters related to signal transduction and clusters related to mycotoxin production were found, which correlated with the phenotypic characterization. The identification of the proteins encompassed in each condition and signal transduction cascade would provide the research community with new information about the B. cinerea infection process and potential candidates of pathogenicity/virulence factors, overcoming plant defenses, and new therapeutic targets.
Collapse
|
12
|
The effects of glucagon and the target of rapamycin (TOR) on skeletal muscle protein synthesis and age-dependent sarcopenia in humans. Clin Nutr ESPEN 2021; 44:15-25. [PMID: 34330459 DOI: 10.1016/j.clnesp.2021.06.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 06/21/2021] [Indexed: 01/07/2023]
Abstract
BACKGROUND AND AIMS Human target of rapamycin (TOR) is a kinase that stimulates protein synthesis in the skeletal muscle in response to amino acids and physical activity. METHODS A comprehensive literature search was conducted on the PubMed database from its inception up to May 2021 to retrieve information on the effects of TOR and glucagon on muscle function. Articles written in English regarding human subjects were included. RESULTS l-leucine activates TOR to initiate protein synthesis in the skeletal muscle. Glucagon has a crucial role suppressing skeletal muscle protein synthesis by increasing l-leucine oxidation and the irreversible loss of this amino acid. Glucagon-induced l-leucine oxidation suppresses TOR and attenuates the ability of skeletal muscle to synthesize proteins. Conditions associated with increased glucagon secretion typically feature reduced ability to synthesize proteins in the skeletal muscle that may evolve into sarcopenia. Animal protein ingestion, unlike vegetable protein, stimulates glucagon secretion. High intake of animal protein increases l-leucine oxidation and promotes the use of amino acids as fuel. Sarcopenia and arterial stiffness characteristically occur together in conditions featuring insulin resistance, such as aging. Insulin resistance mediates the relationship between aging and sarcopenia and arterial stiffness. The loss of skeletal muscle fibers that characterizes sarcopenia is followed by collagen and lipid accumulation. Likewise, insulin resistance is associated with arterial stiffness and intima-media thickening due to adaptive accretion of collagen and lipids in the arterial wall. CONCLUSIONS Human TOR participates in the pathogenesis of sarcopenia and arterial stiffness, although its effects remain to be fully elucidated.
Collapse
|
13
|
Lashgari NA, Roudsari NM, Momtaz S, Ghanaatian N, Kohansal P, Farzaei MH, Afshari K, Sahebkar A, Abdolghaffari AH. Targeting Mammalian Target of Rapamycin: Prospects for the Treatment of Inflammatory Bowel Diseases. Curr Med Chem 2021; 28:1605-1624. [PMID: 32364064 DOI: 10.2174/0929867327666200504081503] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 03/24/2020] [Accepted: 03/29/2020] [Indexed: 12/16/2022]
Abstract
Inflammatory bowel disease (IBD) is a general term for a group of chronic and progressive disorders. Several cellular and biomolecular pathways are implicated in the pathogenesis of IBD, yet the etiology is unclear. Activation of the mammalian target of rapamycin (mTOR) pathway in the intestinal epithelial cells was also shown to induce inflammation. This review focuses on the inhibition of the mTOR signaling pathway and its potential application in treating IBD. We also provide an overview of plant-derived compounds that are beneficial for the IBD management through modulation of the mTOR pathway. Data were extracted from clinical, in vitro and in vivo studies published in English between 1995 and May 2019, which were collected from PubMed, Google Scholar, Scopus and Cochrane library databases. Results of various studies implied that inhibition of the mTOR signaling pathway downregulates the inflammatory processes and cytokines involved in IBD. In this context, a number of natural products might reverse the pathological features of the disease. Furthermore, mTOR provides a novel drug target for IBD. Comprehensive clinical studies are required to confirm the efficacy of mTOR inhibitors in treating IBD.
Collapse
Affiliation(s)
- Naser-Aldin Lashgari
- Department of Toxicology & Pharmacology, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Nazanin Momeni Roudsari
- Department of Toxicology & Pharmacology, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Saeideh Momtaz
- Medicinal Plants Research Center, Institute of Medicinal Plants, ACECR, Karaj, Iran
| | - Negar Ghanaatian
- Department of Toxicology & Pharmacology, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Parichehr Kohansal
- Department of Toxicology & Pharmacology, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mohammad Hosein Farzaei
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Khashayar Afshari
- Experimental Medicine Research Center, Department of pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Amir Hossein Abdolghaffari
- Department of Toxicology & Pharmacology, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| |
Collapse
|
14
|
Egawa N, Tanaka T, Matsufuji S, Yamada K, Ito K, Kitagawa H, Okuyama K, Kitajima Y, Noshiro H. Antitumor effects of low-dose tipifarnib on the mTOR signaling pathway and reactive oxygen species production in HIF-1α-expressing gastric cancer cells. FEBS Open Bio 2021; 11:1465-1475. [PMID: 33773069 PMCID: PMC8091580 DOI: 10.1002/2211-5463.13154] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 02/15/2021] [Accepted: 03/24/2021] [Indexed: 12/24/2022] Open
Abstract
Farnesyltransferase inhibitors (FTIs) suppress tumor aggressiveness in several malignancies by inhibiting Ras signaling. However, treatment of cells with a low dose of the FTI tipifarnib suppresses the expression of hypoxia‐inducible factor‐1α (HIF‐1α) and results in antitumor effects without inhibiting the Ras pathway. Although we previously reported that elevated HIF‐1α expression is associated with an aggressive phenotype in gastric cancer (GC), little is known about the antitumor effects of FTIs on GC. In this study, we examined the relationship between the antitumor effects of low‐dose tipifarnib and HIF‐1α expression in GC cells. Under normoxic conditions, HIF‐1α was expressed only in MKN45 and KATOIII cells. The inhibitory effect of tipifarnib on HIF‐1α was observed in HIF‐1α‐positive cells. Low‐dose tipifarnib had antitumor effects only on HIF‐1α‐positive cells both in vitro and in vivo. Furthermore, low‐dose tipifarnib inactivated ras homolog enriched in brain (Rheb)/mammalian target of rapamycin (mTOR) signaling and decreased intracellular reactive oxygen species (ROS) levels in HIF‐1α‐positive GC cells. Our results that the antitumor effects of low‐dose tipifarnib are at least partially mediated through suppression of mTOR signaling and HIF‐1α expression via inhibition of Rheb farnesylation and reduction in ROS levels. These findings suggest that low‐dose tipifarnib may be capable of exerting an antitumor effect that is dependent on HIF‐1α expression in GC cells. Tipifarnib may have potential as a novel therapeutic agent for HIF‐1α‐expressing GC exhibiting an aggressive phenotype.
Collapse
Affiliation(s)
- Noriyuki Egawa
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Tomokazu Tanaka
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Shohei Matsufuji
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Kohei Yamada
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Kotaro Ito
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Hiroshi Kitagawa
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | | | - Yoshihiko Kitajima
- Department of Surgery, Saga University Faculty of Medicine, Japan.,Department of Surgery, National Hospital Organization Higashisaga Hospital, Saga, Japan
| | - Hirokazu Noshiro
- Department of Surgery, Saga University Faculty of Medicine, Japan
| |
Collapse
|
15
|
Han DY, Han PJ, Rumbold K, Koricha AD, Duan SF, Song L, Shi JY, Li K, Wang QM, Bai FY. Adaptive Gene Content and Allele Distribution Variations in the Wild and Domesticated Populations of Saccharomyces cerevisiae. Front Microbiol 2021; 12:631250. [PMID: 33679656 PMCID: PMC7925643 DOI: 10.3389/fmicb.2021.631250] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 01/26/2021] [Indexed: 11/29/2022] Open
Abstract
Recent studies on population genomics of Saccharomyces cerevisiae have substantially improved our understanding of the genetic diversity and domestication history of the yeast. However, the origin of the domesticated population of S. cerevisiae and the genomic changes responsible for ecological adaption of different populations and lineages remain to be fully revealed. Here we sequenced 64 African strains from various indigenous fermented foods and forests in different African countries and performed a population genomic analysis on them combined with a set of previously sequenced worldwide S. cerevisiae strains representing the maximum genetic diversity of the species documented so far. The result supports the previous observations that the wild and domesticated populations of S. cerevisiae are clearly separated and that the domesticated population diverges into two distinct groups associated with solid- and liquid-state fermentations from a single ancestor. African strains are mostly located in basal lineages of the two domesticated groups, implying a long domestication history of yeast in Africa. We identified genes that mainly or exclusively occur in specific groups or lineages and genes that exhibit evident group or lineage specific allele distribution patterns. Notably, we show that the homing endonuclease VDE is generally absent in the wild but commonly present in the domesticated lineages of S. cerevisiae. The genes with group specific allele distribution patterns are mostly enriched in functionally similar or related fundamental metabolism processes, including the evolutionary conserved TOR signaling pathway.
Collapse
Affiliation(s)
- Da-Yong Han
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Pei-Jie Han
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Karl Rumbold
- School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, South Africa
| | - Anbessa Dabassa Koricha
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.,Department of Biology, College of Natural Sciences, Jimma University, Jimma, Ethiopia
| | - Shou-Fu Duan
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Liang Song
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jun-Yan Shi
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Kuan Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Qi-Ming Wang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Feng-Yan Bai
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
16
|
Mugume Y, Kazibwe Z, Bassham DC. Target of Rapamycin in Control of Autophagy: Puppet Master and Signal Integrator. Int J Mol Sci 2020; 21:ijms21218259. [PMID: 33158137 PMCID: PMC7672647 DOI: 10.3390/ijms21218259] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/01/2020] [Accepted: 11/03/2020] [Indexed: 02/06/2023] Open
Abstract
The target of rapamycin (TOR) is an evolutionarily-conserved serine/threonine kinase that senses and integrates signals from the environment to coordinate developmental and metabolic processes. TOR senses nutrients, hormones, metabolites, and stress signals to promote cell and organ growth when conditions are favorable. However, TOR is inhibited when conditions are unfavorable, promoting catabolic processes such as autophagy. Autophagy is a macromolecular degradation pathway by which cells degrade and recycle cytoplasmic materials. TOR negatively regulates autophagy through phosphorylation of ATG13, preventing activation of the autophagy-initiating ATG1-ATG13 kinase complex. Here we review TOR complex composition and function in photosynthetic and non-photosynthetic organisms. We also review recent developments in the identification of upstream TOR activators and downstream effectors of TOR. Finally, we discuss recent developments in our understanding of the regulation of autophagy by TOR in photosynthetic organisms.
Collapse
|
17
|
Požgajová M, Navrátilová A, Šebová E, Kovár M, Kačániová M. Cadmium-Induced Cell Homeostasis Impairment is Suppressed by the Tor1 Deficiency in Fission Yeast. Int J Mol Sci 2020; 21:ijms21217847. [PMID: 33105893 PMCID: PMC7660220 DOI: 10.3390/ijms21217847] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 10/10/2020] [Accepted: 10/19/2020] [Indexed: 12/16/2022] Open
Abstract
Cadmium has no known physiological function in the body; however, its adverse effects are associated with cancer and many types of organ system damage. Although much has been shown about Cd toxicity, the underlying mechanisms of its responses to the organism remain unclear. In this study, the role of Tor1, a catalytic subunit of the target of rapamycin complex 2 (TORC2), in Cd-mediated effects on cell proliferation, the antioxidant system, morphology, and ionome balance was investigated in the eukaryotic model organism Schizosaccharomyces pombe. Surprisingly, spectrophotometric and biochemical analyses revealed that the growth rate conditions and antioxidant defense mechanisms are considerably better in cells lacking the Tor1 signaling. The malondialdehyde (MDA) content of Tor1-deficient cells upon Cd treatment represents approximately half of the wild-type content. The microscopic determination of the cell morphological parameters indicates the role for Tor1 in cell shape maintenance. The ion content, determined by inductively coupled plasma optical emission spectroscopy (ICP-OES), showed that the Cd uptake potency was markedly lower in Tor1-depleted compared to wild-type cells. Conclusively, we show that the cadmium-mediated cell impairments in the fission yeast significantly depend on the Tor1 signaling. Additionally, the data presented here suggest the yet-undefined role of Tor1 in the transport of ions.
Collapse
Affiliation(s)
- Miroslava Požgajová
- AgroBioTech Research Centre, Slovak University of Agriculture in Nitra, 949 76 Nitra, Slovakia
- Correspondence: ; Tel.: +421-37-641-4919
| | - Alica Navrátilová
- Department of Genetics and Breeding Biology, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture in Nitra, 94976 Nitra, Slovakia;
| | - Eva Šebová
- Institute of Experimental Medicine, Czech Academy of Science, 14220 Prague, Czech Republic;
| | - Marek Kovár
- Department of Plant Physiology, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture in Nitra, 94976 Nitra, Slovakia;
| | - Miroslava Kačániová
- Department of Fruit Science, Viticulture and Enology, Faculty of Horticulture and Landscape Engineering, Slovak University of Agriculture in Nitra, 94976 Nitra, Slovakia;
- Department of Bioenergetics, Food Analysis and Microbiology, Institute of Food Technology and Nutrition, University of Rzeszow, 35-601 Rzeszow, Poland
| |
Collapse
|
18
|
Takahara T, Amemiya Y, Sugiyama R, Maki M, Shibata H. Amino acid-dependent control of mTORC1 signaling: a variety of regulatory modes. J Biomed Sci 2020; 27:87. [PMID: 32799865 PMCID: PMC7429791 DOI: 10.1186/s12929-020-00679-2] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 07/30/2020] [Indexed: 01/10/2023] Open
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) is an essential regulator of cell growth and metabolism through the modulation of protein and lipid synthesis, lysosome biogenesis, and autophagy. The activity of mTORC1 is dynamically regulated by several environmental cues, including amino acid availability, growth factors, energy levels, and stresses, to coordinate cellular status with environmental conditions. Dysregulation of mTORC1 activity is closely associated with various diseases, including diabetes, cancer, and neurodegenerative disorders. The discovery of Rag GTPases has greatly expanded our understanding of the regulation of mTORC1 activity by amino acids, especially leucine and arginine. In addition to Rag GTPases, other factors that also contribute to the modulation of mTORC1 activity have been identified. In this review, we discuss the mechanisms of regulation of mTORC1 activity by particular amino acids.
Collapse
Affiliation(s)
- Terunao Takahara
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.
| | - Yuna Amemiya
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
| | - Risa Sugiyama
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
| | - Masatoshi Maki
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
| | - Hideki Shibata
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
| |
Collapse
|
19
|
Jurkiewicz P, Senicourt L, Ayeb H, Lequin O, Lacapere JJ, Batoko H. A Plant-Specific N-terminal Extension Reveals Evolutionary Functional Divergence within Translocator Proteins. iScience 2020; 23:100889. [PMID: 32087576 PMCID: PMC7033594 DOI: 10.1016/j.isci.2020.100889] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 11/30/2019] [Accepted: 02/03/2020] [Indexed: 12/13/2022] Open
Abstract
Conserved translocator proteins (TSPOs) mediate cell stress responses possibly in a cell-type-specific manner. This work reports on the molecular function of plant TSPO and their possible evolutionary divergence. Arabidopsis thaliana TSPO (AtTSPO) is stress induced and has a conserved polybasic, plant-specific N-terminal extension. AtTSPO reduces water loss by depleting aquaporin PIP2;7 in the plasma membrane. Herein, AtTSPO was found to bind phosphoinositides in vitro, but only full-length AtTSPO or chimeric mouse TSPO with an AtTSPO N-terminus bound PI(4,5)P2in vitro and modified PIP2;7 levels in vivo. Expression of AtTSPO but not its N-terminally truncated variant enhanced phospholipase C activity and depleted PI(4,5)P2 from the plasma membrane and its enrichment in Golgi membranes. Deletion or point mutations within the AtTSPO N-terminus affected PI(4,5)P2 binding and almost prevented AtTSPO-PIP2;7 interaction in vivo. The findings imply functional divergence of plant TSPOs from bacterial and animal counterparts via evolutionary acquisition of the phospholipid-interacting N-terminus.
Collapse
Affiliation(s)
- Pawel Jurkiewicz
- Louvain Institute of Biomolecular Science and Technology (LIBST), University of Louvain (UCLouvain), Croix du Sud 4-5, L7.07.14, 1348 Louvain-la-Neuve, Belgium
| | - Lucile Senicourt
- Sorbonne Université, École Normale Supérieure, PSL University, CNRS, Laboratoire des Biomolécules, 4 Place Jussieu, 75005 Paris, France
| | - Haitham Ayeb
- Louvain Institute of Biomolecular Science and Technology (LIBST), University of Louvain (UCLouvain), Croix du Sud 4-5, L7.07.14, 1348 Louvain-la-Neuve, Belgium
| | - Olivier Lequin
- Sorbonne Université, École Normale Supérieure, PSL University, CNRS, Laboratoire des Biomolécules, 4 Place Jussieu, 75005 Paris, France
| | - Jean-Jacques Lacapere
- Sorbonne Université, École Normale Supérieure, PSL University, CNRS, Laboratoire des Biomolécules, 4 Place Jussieu, 75005 Paris, France
| | - Henri Batoko
- Louvain Institute of Biomolecular Science and Technology (LIBST), University of Louvain (UCLouvain), Croix du Sud 4-5, L7.07.14, 1348 Louvain-la-Neuve, Belgium.
| |
Collapse
|
20
|
Chang K, Kang P, Liu Y, Huang K, Miao T, Sagona AP, Nezis IP, Bodmer R, Ocorr K, Bai H. TGFB-INHB/activin signaling regulates age-dependent autophagy and cardiac health through inhibition of MTORC2. Autophagy 2019; 16:1807-1822. [PMID: 31884871 PMCID: PMC8386626 DOI: 10.1080/15548627.2019.1704117] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Age-related impairment of macroautophagy/autophagy and loss of cardiac tissue homeostasis contribute significantly to cardiovascular diseases later in life. MTOR (mechanistic target of rapamycin kinase) signaling is the most well-known regulator of autophagy, cellular homeostasis, and longevity. The MTOR signaling consists of two structurally and functionally distinct multiprotein complexes, MTORC1 and MTORC2. While MTORC1 is well characterized but the role of MTORC2 in aging and autophagy remains poorly understood. Here we identified TGFB-INHB/activin signaling as a novel upstream regulator of MTORC2 to control autophagy and cardiac health during aging. Using Drosophila heart as a model system, we show that cardiac-specific knockdown of TGFB-INHB/activin-like protein daw induces autophagy and alleviates age-related heart dysfunction, including cardiac arrhythmias and bradycardia. Interestingly, the downregulation of daw activates TORC2 signaling to regulate cardiac autophagy. Activation of TORC2 alone through overexpressing its subunit protein rictor promotes autophagic flux and preserves cardiac function with aging. In contrast, activation of TORC1 does not block autophagy induction in daw knockdown flies. Lastly, either daw knockdown or rictor overexpression in fly hearts prolongs lifespan, suggesting that manipulation of these pathways in the heart has systemic effects on longevity control. Thus, our studies discover the TGFB-INHB/activin-mediated inhibition of TORC2 as a novel mechanism for age-dependent decreases in autophagic activity and cardiac health. Abbreviations: AI: arrhythmia index; BafA1: bafilomycin A1; BMP: bone morphogenetic protein; CQ: chloroquine; CVD: cardiovascular diseases; DI: diastolic interval; ER: endoplasmic reticulum; HP: heart period; HR: heart rate; MTOR: mechanistic target of rapamycin kinase; NGS: normal goat serum; PBST: PBS with 0.1% Triton X-100; PDPK1: 3-phosphoinositide dependent protein kinase 1; RICTOR: RPTOR independent companion of MTOR complex 2; ROI: region of interest; ROUT: robust regression and outlier removal; ROS: reactive oxygen species; R-SMAD: receptor-activated SMAD; SI: systolic interval; SOHA: semi-automatic optical heartbeat analysis; TGFB: transformation growth factor beta; TSC1: TSC complex subunit 1.
Collapse
Affiliation(s)
- Kai Chang
- Department of Genetics, Development, and Cell Biology, Iowa State University , Ames, IA, USA
| | - Ping Kang
- Department of Genetics, Development, and Cell Biology, Iowa State University , Ames, IA, USA
| | - Ying Liu
- Department of Genetics, Development, and Cell Biology, Iowa State University , Ames, IA, USA
| | - Kerui Huang
- Department of Genetics, Development, and Cell Biology, Iowa State University , Ames, IA, USA
| | - Ting Miao
- Department of Genetics, Development, and Cell Biology, Iowa State University , Ames, IA, USA
| | | | - Ioannis P Nezis
- School of Life Sciences, University of Warwick , Coventry, UK
| | - Rolf Bodmer
- Development, Aging, and Regeneration Program, Sanford-Burnham-Prebys Medical Discovery Institute , La Jolla, CA, USA
| | - Karen Ocorr
- Development, Aging, and Regeneration Program, Sanford-Burnham-Prebys Medical Discovery Institute , La Jolla, CA, USA
| | - Hua Bai
- Department of Genetics, Development, and Cell Biology, Iowa State University , Ames, IA, USA
| |
Collapse
|
21
|
Xiong F, Liu M, Zhuo F, Yin H, Deng K, Feng S, Liu Y, Luo X, Feng L, Zhang S, Li Z, Ren M. Host-induced gene silencing of BcTOR in Botrytis cinerea enhances plant resistance to grey mould. MOLECULAR PLANT PATHOLOGY 2019; 20:1722-1739. [PMID: 31622007 PMCID: PMC6859489 DOI: 10.1111/mpp.12873] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Botrytis cinerea is the causal agent of grey mould for more than 200 plant species, including economically important vegetables, fruits and crops, which leads to economic losses worldwide. Target of rapamycin (TOR) acts a master regulator to control cell growth and proliferation by integrating nutrient, energy and growth factors in eukaryotic species, but little is known about whether TOR can function as a practicable target in the control of plant fungal pathogens. Here, we characterize TOR signalling of B. cinerea in the regulation of growth and pathogenicity as well as its potential value in genetic engineering for crop protection by bioinformatics analysis, pharmacological assays, biochemistry and genetics approaches. The results show that conserved TOR signalling occurs, and a functional FK506-binding protein 12 kD (FKBP12) mediates the interaction between rapamycin and B. cinerea TOR (BcTOR). RNA sequencing (RNA-Seq) analysis revealed that BcTOR displayed conserved functions, particularly in controlling growth and metabolism. Furthermore, pathogenicity assay showed that BcTOR inhibition efficiently reduces the infection of B. cinerea in plant leaves of Arabidopsis and potato or tomato fruits. Additionally, transgenic plants expressing double-stranded RNA of BcTOR through the host-induced gene silencing method could produce abundant small RNAs targeting BcTOR, and significantly block the occurrence of grey mould in potato and tomato. Taken together, our results suggest that BcTOR is an efficient target for genetic engineering in control of grey mould, and also a potential and promising target applied in the biocontrol of plant fungal pathogens.
Collapse
Affiliation(s)
- Fangjie Xiong
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Mei Liu
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Fengping Zhuo
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
- School of Chemistry and Chemical EngineeringChongqing University of Science and TechnologyChongqing401331China
| | - Huan Yin
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Kexuan Deng
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Shun Feng
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Yudong Liu
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Xiumei Luo
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Li Feng
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Shumin Zhang
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Zhengguo Li
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Maozhi Ren
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
- Institute of Urban AgricultureChinese Academy of Agricultural Sciences/National Chengdu Agricultural Science and Technology CenterChengdu610000China
| |
Collapse
|
22
|
Maruska KP, Sohn YC, Fernald RD. Mechanistic target of rapamycin (mTOR) implicated in plasticity of the reproductive axis during social status transitions. Gen Comp Endocrinol 2019; 282:113209. [PMID: 31226256 PMCID: PMC6718321 DOI: 10.1016/j.ygcen.2019.113209] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 06/13/2019] [Accepted: 06/17/2019] [Indexed: 01/04/2023]
Abstract
The highly conserved brain-pituitary-gonadal (BPG) axis controls reproduction in all vertebrates, so analyzing the regulation of this signaling cascade is important for understanding reproductive competence. The protein kinase mechanistic target of rapamycin (mTOR) functions as a conserved regulator of cellular growth and metabolism in all eukaryotes, and also regulates the reproductive axis in mammals. However, whether mTOR might also regulate the BPG axis in non-mammalian vertebrates remains unexplored. We used complementary experimental approaches in an African cichlid fish, Astatotilapia burtoni, to demonstrate that mTOR is involved in regulation of the brain, pituitary, and testes when males rise in rank to social dominance. mTOR or downstream components of its signaling pathway (p-p70S6K) were detected in gonadotropin-releasing hormone (GnRH1) neurons, the pituitary, and testes. Transcript levels of mtor in the pituitary and testes also varied when reproductively-suppressed subordinate males rose in social rank to become dominant reproductively-active males, a transition similar to puberty in mammals. Intracerebroventricular injection of the mTORC1 inhibitor, rapamycin, revealed a role for mTOR in the socially-induced hypertrophy of GnRH1 neurons. Rapamycin treatment also had effects at the pituitary and testes, suggesting involvement of the mTORC1 complex at multiple levels of the reproductive axis. Thus, we show that mTOR regulation of BPG function is conserved to fishes, likely playing important roles in regulating reproduction and fertility across all male vertebrates.
Collapse
Affiliation(s)
- Karen P Maruska
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, United States.
| | - Young Chang Sohn
- Department of Marine Molecular Bioscience, Gangneung-Wonju National University, Gangneung, Gangwon 25457, Republic of Korea
| | - Russell D Fernald
- Department of Biology, Stanford University, Stanford, CA 94305, United States
| |
Collapse
|
23
|
Waltero C, de Abreu LA, Alonso T, Nunes-da-Fonseca R, da Silva Vaz I, Logullo C. TOR as a Regulatory Target in Rhipicephalus microplus Embryogenesis. Front Physiol 2019; 10:965. [PMID: 31417424 PMCID: PMC6684781 DOI: 10.3389/fphys.2019.00965] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 07/11/2019] [Indexed: 12/11/2022] Open
Abstract
Embryogenesis is a metabolically intensive process carried out under tightly controlled conditions. The insulin signaling pathway regulates glucose homeostasis and is essential for reproduction in metazoan model species. Three key targets are part of this signaling pathway: protein kinase B (PKB, or AKT), glycogen synthase kinase 3 (GSK-3), and target of rapamycin (TOR). While the role of AKT and GSK-3 has been investigated during tick embryonic development, the role of TOR remains unknown. In this study, TOR and two other downstream effectors, namely S6 kinase (S6K) and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1), were investigated in in vitro studies using the tick embryonic cell line BME26. First, we show that exogenous insulin can stimulate TOR transcription. Second, TOR chemical inhibition led to a decrease in BME26 cell viability, loss of membrane integrity, and downregulation of S6K and 4E-BP1 transcription. Conversely, treating BME26 cells with chemical inhibitors of AKT or GSK-3 did not affect S6K and 4E-BP1 transcription, showing that TOR is specifically required to activate its downstream targets. To address the role of TOR in tick reproduction, in vivo studies were performed. Analysis of relative transcription during different stages of tick embryonic development showed different levels of transcription for TOR, and a maternal deposition of S6K and 4E-BP1 transcripts. Injection of TOR double-stranded RNA (dsRNA) into partially fed females led to a slight delay in oviposition, an atypical egg external morphology, decreased vitellin content in eggs, and decreased larval hatching. Taken together, our data show that the TOR signaling pathway is important for tick reproduction, that TOR acts as a regulatory target in Rhipicephalus microplus embryogenesis and represents a promising target for the development of compounds for tick control.
Collapse
Affiliation(s)
- Camila Waltero
- Laboratório Integrado de Bioquímica Hatisaburo Masuda and Laboratório Integrado de Ciências Morfofuncionais, Instituto de Biodiversidade e Sustentabilidade NUPEM, Universidade Federal do Rio de Janeiro, Macaé, Brazil
| | - Leonardo Araujo de Abreu
- Laboratório Integrado de Bioquímica Hatisaburo Masuda and Laboratório Integrado de Ciências Morfofuncionais, Instituto de Biodiversidade e Sustentabilidade NUPEM, Universidade Federal do Rio de Janeiro, Macaé, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Brazil
| | - Thayná Alonso
- Laboratório Integrado de Bioquímica Hatisaburo Masuda and Laboratório Integrado de Ciências Morfofuncionais, Instituto de Biodiversidade e Sustentabilidade NUPEM, Universidade Federal do Rio de Janeiro, Macaé, Brazil
| | - Rodrigo Nunes-da-Fonseca
- Laboratório Integrado de Bioquímica Hatisaburo Masuda and Laboratório Integrado de Ciências Morfofuncionais, Instituto de Biodiversidade e Sustentabilidade NUPEM, Universidade Federal do Rio de Janeiro, Macaé, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Brazil
| | - Itabajara da Silva Vaz
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Brazil
- Centro de Biotecnologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Carlos Logullo
- Laboratório Integrado de Bioquímica Hatisaburo Masuda and Laboratório Integrado de Ciências Morfofuncionais, Instituto de Biodiversidade e Sustentabilidade NUPEM, Universidade Federal do Rio de Janeiro, Macaé, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Brazil
| |
Collapse
|
24
|
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: 208] [Impact Index Per Article: 41.6] [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.
Collapse
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
| |
Collapse
|
25
|
Abstract
RES-529 (previously named Palomid 529, P529) is a phosphoinositide 3-kinase (PI3K)/AKT/mechanistic target of rapamycin (mTOR) pathway inhibitor that interferes with the pathway through both mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2) dissociation. This compound is currently being developed in oncology and ophthalmology. The oncology focus is for the treatment of glioblastoma, where it has received orphan designation by the US Food and Drug Administration, and prostate cancer. We present a review of the PI3K/AKT/mTOR pathway, its role in tumorigenesis, and the potential of RES-529 in cancer treatment. RES-529 inhibits mTORC1/mTORC2 activity in various cancer cell lines, as noted by decreased phosphorylation of substrates including ribosomal protein S6, 4E-BP1, and AKT, leading to cell growth inhibition and death, with activity generally in the range of 5–15 μmol/l. In animal tumor models where the PI3K/AKT/mTOR pathway is abnormally activated (i.e. glioblastoma, prostate cancer, and breast cancer), RES-529 reduces tumor growth by as much as 78%. RES-529 treatment is synergistic with radiation therapy, chemotherapy, and hormonal therapy in reducing tumor growth, potentially by preventing PI3K/AKT/mTOR pathway activation associated with these treatments. Furthermore, this compound has shown antiangiogenic activity in several animal models. mTORC1 and mTORC2 have redundant and distinct activities that contribute toward oncogenesis. Current inhibitors of this pathway have primarily targeted mTORC1, but have shown limited clinical efficacy. Inhibitors of mTORC1 and mTORC2 such as RES-529 may therefore have the potential to overcome the deficiencies found in targeting only mTORC1.
Collapse
|
26
|
An In Vitro TORC1 Kinase Assay That Recapitulates the Gtr-Independent Glutamine-Responsive TORC1 Activation Mechanism on Yeast Vacuoles. Mol Cell Biol 2017; 37:MCB.00075-17. [PMID: 28483912 DOI: 10.1128/mcb.00075-17] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/01/2017] [Indexed: 01/03/2023] Open
Abstract
Evolutionarily conserved target of rapamycin (TOR) complex 1 (TORC1) responds to nutrients, especially amino acids, to promote cell growth. In the yeast Saccharomyces cerevisiae, various nitrogen sources activate TORC1 with different efficiencies, although the mechanism remains elusive. Leucine, and perhaps other amino acids, was reported to activate TORC1 via the heterodimeric small GTPases Gtr1-Gtr2, the orthologues of the mammalian Rag GTPases. More recently, an alternative Gtr-independent TORC1 activation mechanism that may respond to glutamine was reported, although its molecular mechanism is not clear. In studying the nutrient-responsive TORC1 activation mechanism, the lack of an in vitro assay hinders associating particular nutrient compounds with the TORC1 activation status, whereas no in vitro assay that shows nutrient responsiveness has been reported. In this study, we have developed a new in vitro TORC1 kinase assay that reproduces, for the first time, the nutrient-responsive TORC1 activation. This in vitro TORC1 assay recapitulates the previously predicted Gtr-independent glutamine-responsive TORC1 activation mechanism. Using this system, we found that this mechanism specifically responds to l-glutamine, resides on the vacuolar membranes, and involves a previously uncharacterized Vps34-Vps15 phosphatidylinositol (PI) 3-kinase complex and the PI-3-phosphate [PI(3)P]-binding FYVE domain-containing vacuolar protein Pib2. Thus, this system was proved to be useful for dissecting the glutamine-responsive TORC1 activation mechanism.
Collapse
|
27
|
Affiliation(s)
- Philipp Kaldis
- Cell Division and Cancer Research, Institute of Molecular and Cell Biology, Agency for Science, Technology and ResearchSingapore, Singapore; Department of Biochemistry, National University of SingaporeSingapore, Singapore
| |
Collapse
|
28
|
Heaven MR, Flint D, Randall SM, Sosunov AA, Wilson L, Barnes S, Goldman JE, Muddiman DC, Brenner M. Composition of Rosenthal Fibers, the Protein Aggregate Hallmark of Alexander Disease. J Proteome Res 2016; 15:2265-82. [PMID: 27193225 PMCID: PMC5036859 DOI: 10.1021/acs.jproteome.6b00316] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Alexander disease (AxD) is a neurodegenerative disorder characterized by astrocytic protein aggregates called Rosenthal fibers (RFs). We used mouse models of AxD to determine the protein composition of RFs to obtain information about disease mechanisms including the hypothesis that sequestration of proteins in RFs contributes to disease. A method was developed for RF enrichment, and analysis of the resulting fraction using isobaric tags for relative and absolute quantitation mass spectrometry identified 77 proteins not previously associated with RFs. Three of five proteins selected for follow-up were confirmed enriched in the RF fraction by immunobloting of both the AxD mouse models and human patients: receptor for activated protein C kinase 1 (RACK1), G1/S-specific cyclin D2, and ATP-dependent RNA helicase DDX3X. Immunohistochemistry validated cyclin D2 as a new RF component, but results for RACK1 and DDX3X were equivocal. None of these was decreased in the non-RF fractions compared to controls. A similar result was obtained for the previously known RF component, alphaB-crystallin, which had been a candidate for sequestration. Thus, no support was obtained for the sequestration hypothesis for AxD. Providing possible insight into disease progression, the association of several of the RF proteins with stress granules suggests a role for stress granules in the origin of RFs.
Collapse
Affiliation(s)
- Michael R. Heaven
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Alabama 35294
| | - Daniel Flint
- Department of Neurobiology and the Civitan International Research Center, Center for Glial Biology in Medicine, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Shan M. Randall
- Keck Fourier Transform Mass Spectrometry Laboratory, Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695
| | | | - Landon Wilson
- Department of Pharmacology and Toxicology, Targeted Metabolomics and Proteomics Laboratory, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Stephen Barnes
- Department of Pharmacology and Toxicology, Targeted Metabolomics and Proteomics Laboratory, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - James E. Goldman
- Department of Pathology & Cell Biology, Columbia University, New York, New York, 10032
| | - David C. Muddiman
- Keck Fourier Transform Mass Spectrometry Laboratory, Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695
| | - Michael Brenner
- Department of Neurobiology and the Civitan International Research Center, Center for Glial Biology in Medicine, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama 35294
| |
Collapse
|
29
|
Xiong F, Dong P, Liu M, Xie G, Wang K, Zhuo F, Feng L, Yang L, Li Z, Ren M. Tomato FK506 Binding Protein 12KD (FKBP12) Mediates the Interaction between Rapamycin and Target of Rapamycin (TOR). FRONTIERS IN PLANT SCIENCE 2016; 7:1746. [PMID: 27917191 PMCID: PMC5114585 DOI: 10.3389/fpls.2016.01746] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 11/04/2016] [Indexed: 05/18/2023]
Abstract
Target of Rapamycin (TOR) signaling is an important regulator in multiple organisms including yeast, plants, and animals. However, the TOR signaling in plants is much less understood as compared to that in yeast and animals. TOR kinase can be efficiently suppressed by rapamycin in the presence of functional FK506 Binding Protein 12 KD (FKBP12) in yeast and animals. In most examined higher plants rapamycin fails to inhibit TOR kinase due to the non-functional FKBP12. Here we find that tomato plants showed obvious growth inhibition when treated with rapamycin and the inhibitory phenotype is similar to suppression of TOR causing by active-site TOR inhibitors (asTORis) such as KU63794, AZD8055, and Torin1. The chemical genetic assays using TOR inhibitors and heterologous expressing SlFKBP12 in Arabidopsis indicated that the TOR signaling is functional in tomato. The protein gel shifting and TOR inhibitors combination assays showed that SlFKBP12 can mediate the interaction between rapamycin and TOR. Furthermore, comparative expression profile analysis between treatments with rapamycin and KU63794 identified highly overlapped Differentially Expressed Genes (DEGs) which are involved in many anabolic and catabolic processes, such as photosynthesis, cell wall restructuring, and senescence in tomato. These observations suggest that SlFFBP12 is functional in tomato. The results provided basic information of TOR signaling in tomato, and also some new insights into how TOR controls plant growth and development through reprogramming the transcription profiles.
Collapse
Affiliation(s)
- Fangjie Xiong
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Pan Dong
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Mei Liu
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Gengxin Xie
- Center of Space Exploration, Ministry of EducationChongqing, China
| | - Kai Wang
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Fengping Zhuo
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Li Feng
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Lu Yang
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Zhengguo Li
- School of Life Sciences, Chongqing UniversityChongqing, China
- *Correspondence: Zhengguo Li
| | - Maozhi Ren
- School of Life Sciences, Chongqing UniversityChongqing, China
- Center of Space Exploration, Ministry of EducationChongqing, China
- Maozhi Ren
| |
Collapse
|
30
|
Hatano T, Morigasaki S, Tatebe H, Ikeda K, Shiozaki K. Fission yeast Ryh1 GTPase activates TOR Complex 2 in response to glucose. Cell Cycle 2015; 14:848-56. [PMID: 25590601 PMCID: PMC4612450 DOI: 10.1080/15384101.2014.1000215] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The Target Of Rapamycin (TOR) is an evolutionarily conserved protein kinase that forms 2 distinct protein complexes referred to as TOR complex 1 (TORC1) and 2 (TORC2). Recent extensive studies have demonstrated that TORC1 is under the control of the small GTPases Rheb and Rag that funnel multiple input signals including those derived from nutritional sources; however, information is scarce as to the regulation of TORC2. A previous study using the model system provided by the fission yeast Schizosaccharomyces pombe identified Ryh1, a Rab-family GTPase, as an activator of TORC2. Here, we show that the nucleotide-binding state of Ryh1 is regulated in response to glucose, mediating this major nutrient signal to TORC2. In glucose-rich growth media, the GTP-bound form of Ryh1 induces TORC2-dependent phosphorylation of Gad8, a downstream target of TORC2 in fission yeast. Upon glucose deprivation, Ryh1 becomes inactive, which turns off the TORC2-Gad8 pathway. During glucose starvation, however, Gad8 phosphorylation by TORC2 gradually recovers independently of Ryh1, implying an additional TORC2 activator that is regulated negatively by glucose. The paired positive and negative regulatory mechanisms may allow fine-tuning of the TORC2-Gad8 pathway, which is essential for growth under glucose-limited environment.
Collapse
Affiliation(s)
- Tomoyuki Hatano
- a Graduate School of Biological Sciences , Nara Institute of Science and Technology , Ikoma , Nara , Japan
| | | | | | | | | |
Collapse
|
31
|
Bitto A, Wang AM, Bennett CF, Kaeberlein M. Biochemical Genetic Pathways that Modulate Aging in Multiple Species. Cold Spring Harb Perspect Med 2015; 5:5/11/a025114. [PMID: 26525455 DOI: 10.1101/cshperspect.a025114] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The mechanisms underlying biological aging have been extensively studied in the past 20 years with the avail of mainly four model organisms: the budding yeast Saccharomyces cerevisiae, the nematode Caenorhabditis elegans, the fruitfly Drosophila melanogaster, and the domestic mouse Mus musculus. Extensive research in these four model organisms has identified a few conserved genetic pathways that affect longevity as well as metabolism and development. Here, we review how the mechanistic target of rapamycin (mTOR), sirtuins, adenosine monophosphate-activated protein kinase (AMPK), growth hormone/insulin-like growth factor 1 (IGF-1), and mitochondrial stress-signaling pathways influence aging and life span in the aforementioned models and their possible implications for delaying aging in humans. We also draw some connections between these biochemical pathways and comment on what new developments aging research will likely bring in the near future.
Collapse
Affiliation(s)
- Alessandro Bitto
- Department of Pathology, University of Washington, Seattle, Washington 98195
| | - Adrienne M Wang
- Department of Pathology, University of Washington, Seattle, Washington 98195
| | | | - Matt Kaeberlein
- Department of Pathology, University of Washington, Seattle, Washington 98195
| |
Collapse
|
32
|
Farhan MA, Carmine-Simmen K, Lewis JD, Moore RB, Murray AG. Endothelial Cell mTOR Complex-2 Regulates Sprouting Angiogenesis. PLoS One 2015; 10:e0135245. [PMID: 26295809 PMCID: PMC4546419 DOI: 10.1371/journal.pone.0135245] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 07/20/2015] [Indexed: 12/11/2022] Open
Abstract
Tumor neovascularization is targeted by inhibition of vascular endothelial growth factor (VEGF) or the receptor to prevent tumor growth, but drug resistance to angiogenesis inhibition limits clinical efficacy. Inhibition of the phosphoinositide 3 kinase pathway intermediate, mammalian target of rapamycin (mTOR), also inhibits tumor growth and may prevent escape from VEGF receptor inhibitors. mTOR is assembled into two separate multi-molecular complexes, mTORC1 and mTORC2. The direct effect of mTORC2 inhibition on the endothelium and tumor angiogenesis is poorly defined. We used pharmacological inhibitors and RNA interference to determine the function of mTORC2 versus Akt1 and mTORC1 in human endothelial cells (EC). Angiogenic sprouting, EC migration, cytoskeleton re-organization, and signaling events regulating matrix adhesion were studied. Sustained inactivation of mTORC1 activity up-regulated mTORC2-dependent Akt1 activation. In turn, ECs exposed to mTORC1-inhibition were resistant to apoptosis and hyper-responsive to renal cell carcinoma (RCC)-stimulated angiogenesis after relief of the inhibition. Conversely, mTORC1/2 dual inhibition or selective mTORC2 inactivation inhibited angiogenesis in response to RCC cells and VEGF. mTORC2-inactivation decreased EC migration more than Akt1- or mTORC1-inactivation. Mechanistically, mTORC2 inactivation robustly suppressed VEGF-stimulated EC actin polymerization, and inhibited focal adhesion formation and activation of focal adhesion kinase, independent of Akt1. Endothelial mTORC2 regulates angiogenesis, in part by regulation of EC focal adhesion kinase activity, matrix adhesion, and cytoskeletal remodeling, independent of Akt/mTORC1.
Collapse
Affiliation(s)
| | | | - John D. Lewis
- Department of Oncology, University of Alberta, Edmonton, Canada
| | - Ronald B. Moore
- Department of Surgery, University of Alberta, Edmonton, Canada
| | - Allan G. Murray
- Department of Medicine, University of Alberta, Edmonton, Canada
- * E-mail:
| |
Collapse
|
33
|
Tryptophan-Dependent Control of Colony Formation After DNA Damage via Sea3-Regulated TORC1 Signaling in Saccharomyces cerevisiae. G3-GENES GENOMES GENETICS 2015; 5:1379-89. [PMID: 25943524 PMCID: PMC4502372 DOI: 10.1534/g3.115.018721] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Saccharomyces cerevisiaeIml1 complex inhibits TORC1 signaling and SEACAT antagonizes the Iml1 complex. Conditions in which SEACAT functions to inhibit Iml1 and, hence, TORC1 signaling, remain largely unknown. The SEACAT member Sea3 was linked previously to telomere maintenance and DNA repair via genome-wide genetic and physical interaction studies. Therefore, we questioned whether Sea3 functioned through TORC1 to influence these pathways. Deletion of SEA3 delayed the emergence of telomerase-independent survivors that use break-induced replication (BIR) to maintain their telomeres. Similarly, sea3∆ mutants exhibited a delay in colony formation in a BIR assay strain after double-strand break (DSB) induction as well as on the DNA-damaging agent bleomycin. Deletion of IML1 rescued the impaired growth of sea3∆ mutants after DNA damage, consistent with Sea3 functioning as a regulator of TORC1 signaling. The delay was not attributable to slowed DSB repair or termination of the DNA damage checkpoint but to tryptophan auxotrophy. High levels of tryptophan in yeast peptone dextrose media did not rescue the delay in colony formation, suggesting a defect in tryptophan import, although levels of the high-affinity tryptophan permease Tat2 were not perturbed in the sea3Δ mutant. Addition of quinolinic acid, an intermediate of the de novo NAD+ biosynthetic pathway, however, rescued the delay in colony formation in the sea3Δ mutant. Together, these findings highlight the importance of enforcement of TORC1 signaling and suggest that internal tryptophan levels influence growth recovery post DNA damage through the role of tryptophan in NAD+ synthesis.
Collapse
|
34
|
Andreoli A, Ruf M, Itin P, Pluschke G, Schmid P. Phosphorylation of the ribosomal protein S6, a marker of mTOR (mammalian target of rapamycin) pathway activation, is strongly increased in hypertrophic scars and keloids. Br J Dermatol 2015; 172:1415-7. [DOI: 10.1111/bjd.13523] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- A. Andreoli
- Swiss Tropical and Public Health Institute; Socinstr. 57 Basel Switzerland
- University of Basel; Petersplatz 1 Basel Switzerland
| | - M.T. Ruf
- Swiss Tropical and Public Health Institute; Socinstr. 57 Basel Switzerland
- University of Basel; Petersplatz 1 Basel Switzerland
| | - P. Itin
- Department of Dermatology; University Hospital; Basel Switzerland
| | - G. Pluschke
- Swiss Tropical and Public Health Institute; Socinstr. 57 Basel Switzerland
- University of Basel; Petersplatz 1 Basel Switzerland
| | - P. Schmid
- Swiss Tropical and Public Health Institute; Socinstr. 57 Basel Switzerland
- University of Basel; Petersplatz 1 Basel Switzerland
| |
Collapse
|
35
|
Doi A, Fujimoto A, Sato S, Uno T, Kanda Y, Asami K, Tanaka Y, Kita A, Satoh R, Sugiura R. Chemical genomics approach to identify genes associated with sensitivity to rapamycin in the fission yeastSchizosaccharomyces pombe. Genes Cells 2015; 20:292-309. [DOI: 10.1111/gtc.12223] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/13/2014] [Indexed: 02/02/2023]
Affiliation(s)
- Akira Doi
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
- Japan Society for the Promotion of Science; 1-8 Chiyoda-ku Tokyo 102-8472 Japan
| | - Ayumi Fujimoto
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
| | - Shun Sato
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
| | - Takaya Uno
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
| | - Yuki Kanda
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
| | - Keita Asami
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
| | - Yuriko Tanaka
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
| | - Ayako Kita
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
| | - Ryosuke Satoh
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
| | - Reiko Sugiura
- Laboratory of Molecular Pharmacogenomics; School of Pharmaceutical Sciences; Kinki University; Kowakae 3-4-1 Higashi-Osaka 577-8502 Japan
| |
Collapse
|
36
|
Dong P, Xiong F, Que Y, Wang K, Yu L, Li Z, Ren M. Expression profiling and functional analysis reveals that TOR is a key player in regulating photosynthesis and phytohormone signaling pathways in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2015; 6:677. [PMID: 26442001 PMCID: PMC4561354 DOI: 10.3389/fpls.2015.00677] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 08/17/2015] [Indexed: 05/06/2023]
Abstract
Target of rapamycin (TOR) acts as a master regulator to control cell growth by integrating nutrient, energy, and growth factors in all eukaryotic species. TOR plays an evolutionarily conserved role in regulating the transcription of genes associated with anabolic and catabolic processes in Arabidopsis, but little is known about the functions of TOR in photosynthesis and phytohormone signaling, which are unique features of plants. In this study, AZD8055 (AZD) was screened as the strongest active-site TOR inhibitor (asTORi) in Arabidopsis compared with TORIN1 and KU63794 (KU). Gene expression profiles were evaluated using RNA-seq after treating Arabidopsis seedlings with AZD. More than three-fold differentially expressed genes (DEGs) were identified in AZD-treated plants relative to rapamycin-treated plants in previous studies. Most of the DEGs and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways involved in cell wall elongation, ribosome biogenesis, and cell autophagy were common to both AZD- and rapamycin-treated samples, but AZD displayed much broader and more efficient inhibition of TOR compared with rapamycin. Importantly, the suppression of TOR by AZD resulted in remodeling of the expression profile of the genes associated with photosynthesis and various phytohormones, indicating that TOR plays a crucial role in modulating photosynthesis and phytohormone signaling in Arabidopsis. These newly identified DEGs expand the understanding of TOR signaling in plants. This study elucidates the novel functions of TOR in photosynthesis and phytohormone signaling and provides a platform to study the downstream targets of TOR in Arabidopsis.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Maozhi Ren
- *Correspondence: Maozhi Ren, School of Life Sciences, Chongqing University, 174 Shazheng ST, Shapingba, Chongqing 400045, China
| |
Collapse
|
37
|
Liu C, Xue R, Wu D, Wu L, Chen C, Tan W, Chen Y, Dong Y. REDD1 attenuates cardiac hypertrophy via enhancing autophagy. Biochem Biophys Res Commun 2014; 454:215-20. [PMID: 25450383 DOI: 10.1016/j.bbrc.2014.10.079] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 10/15/2014] [Indexed: 10/24/2022]
Abstract
Cardiac hypertrophy is a major risk factor of cardiovascular morbidity and mortality. Autophagy is established to be involved in regulating cardiac hypertrophy. REDD1, a stress-responsive protein, is proved to contribute in autophagy induction. However, the role of REDD1 in cardiac hypertrophy remains unknown. Our study demonstrated that REDD1 knockdown by RNAi exacerbated phenylephrine (PE)-induced cardiac hypertrophy, manifested by increased hypertrophic markers such as ANP and cell surface area. In addition, we discovered that ERK1/2 signaling pathway was involved in the effect of REDD1 on hypertrophy. Moreover, our study showed that REDD1 knockdown impaired autophagy in hypertrophied cardiomyocytes. mTOR, a signaling molecule governing autophagy induction, was activated by the knockdown of REDD1 under PE stress. Importantly, the pro-hypertrophic effect of REDD1 knockdown was significantly reversed by the autophagy enhancer rapamycin. Taken together, we firstly prove that REDD1 is essential for inhibiting cardiac hypertrophy by enhancing autophagy.
Collapse
Affiliation(s)
- Chen Liu
- Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China; Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou 510080, China
| | - Ruicong Xue
- Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China; Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou 510080, China
| | - Dexi Wu
- Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China; Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou 510080, China
| | - Lingling Wu
- Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China; Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou 510080, China
| | - Cong Chen
- Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China; Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou 510080, China
| | - Weiping Tan
- Department of Respiratory, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China
| | - Yili Chen
- Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China; Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou 510080, China
| | - Yugang Dong
- Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China; Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou 510080, China.
| |
Collapse
|
38
|
Mahboubi H, Stochaj U. Nucleoli and Stress Granules: Connecting Distant Relatives. Traffic 2014; 15:1179-93. [DOI: 10.1111/tra.12191] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 06/30/2014] [Accepted: 06/30/2014] [Indexed: 12/19/2022]
Affiliation(s)
- Hicham Mahboubi
- Department of Physiology; McGill University; 3655 Promenade Sir William Osler Montreal Quebec H3G 1Y6 Canada
| | - Ursula Stochaj
- Department of Physiology; McGill University; 3655 Promenade Sir William Osler Montreal Quebec H3G 1Y6 Canada
| |
Collapse
|
39
|
Hoshii T, Matsuda S, Hirao A. Pleiotropic roles of mTOR complexes in haemato-lymphopoiesis and leukemogenesis. J Biochem 2014; 156:73-83. [PMID: 24962700 DOI: 10.1093/jb/mvu037] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Mammalian/mechanistic target of rapamycin (mTOR) is a highly conserved serine/threonine kinase that responds to environmental determinants such as growth factor concentration, nutrient availability, energy sufficiency and stress. mTOR forms two different complexes, called mTOR complex 1 (mTORC1) and mTORC2, and these complexes have distinct substrate molecules that function in the regulation of protein translation and cellular metabolism. Although mTOR was originally discovered as a target protein of rapamycin, a natural macrolide immunosuppressant, rapamycin mainly inhibits the kinase activity of mTORC1, whereas mTORC2 is affected to a much lesser extent. The inhibitory effects of rapamycin on mTORC1 substrates are complex, and the use of rapamycin to investigate mTORC functions may provide misleading results. In contrast to pharmacological inhibition, studies using genetic approaches to the disruption of mTORC subunits have clearly demonstrated the physiological roles of the distinct mTOR complexes in organogenesis and tumourigenesis. In this review, we provide an overview of current knowledge about the roles of the mTOR complexes in haemato-lymphopoiesis and leukemogenesis.
Collapse
Affiliation(s)
- Takayuki Hoshii
- Division of Molecular Genetics, Cancer and Stem Cell Research Program, Cancer Research Institute, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan; and Department of Cell Signaling, Institute of Biomedical Science, Kansai Medical University, Hirakata, Osaka 570-8506, Japan
| | - Satoshi Matsuda
- Division of Molecular Genetics, Cancer and Stem Cell Research Program, Cancer Research Institute, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan; and Department of Cell Signaling, Institute of Biomedical Science, Kansai Medical University, Hirakata, Osaka 570-8506, Japan
| | - Atsushi Hirao
- Division of Molecular Genetics, Cancer and Stem Cell Research Program, Cancer Research Institute, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan; and Department of Cell Signaling, Institute of Biomedical Science, Kansai Medical University, Hirakata, Osaka 570-8506, Japan
| |
Collapse
|
40
|
Henriques R, Bögre L, Horváth B, Magyar Z. Balancing act: matching growth with environment by the TOR signalling pathway. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:2691-701. [PMID: 24567496 DOI: 10.1093/jxb/eru049] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
One of the most fundamental aspects of growth in plants is its plasticity in relation to fluctuating environmental conditions. Growth of meristematic cells relies predominantly on protein synthesis, one of the most energy-consuming activities in cells, and thus is tightly regulated in accordance with the available nutrient and energy supplies. The Target of Rapamycin (TOR) signalling pathway takes a central position in this regulation. The core of the TOR signalling pathway is conserved throughout evolution, and can be traced back to the last eukaryotic common ancestor. In plants, a single complex constitutes the TOR signalling pathway. Manipulating the components of the TOR complex in Arabidopsis highlighted its common role as a major regulator of protein synthesis and metabolism, that is also involved in other biological functions such as cell-wall integrity, regulation of cell proliferation, and cell size. TOR, as an integral part of the auxin signalling pathway, connects hormonal and nutrient pathways. Downstream of TOR, S6 kinase and the ribosomal S6 protein have been shown to mediate several of these responses, although there is evidence of other complex non-linear TOR signalling pathway structures.
Collapse
Affiliation(s)
- Rossana Henriques
- Center for Research in Agricultural Genomics (CRAG), Consortium CSIC-IRTA-UAB-UB, Parc de Recerca UAB, Edifici CRAG, Campus UAB, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain
| | - László Bögre
- School of Biological Sciences, Royal Holloway, University of London, Egham Hill, Egham, Surrey TW20 0EX, UK
| | - Beátrix Horváth
- School of Biological Sciences, Royal Holloway, University of London, Egham Hill, Egham, Surrey TW20 0EX, UK
| | - Zoltán Magyar
- Institute of Plant Biology, Biological Research Centre, Temesvári kru. 62, POB 521, H-6701, Szeged, Hungary
| |
Collapse
|
41
|
Sekiguchi T, Kamada Y, Furuno N, Funakoshi M, Kobayashi H. Amino acid residues required for Gtr1p-Gtr2p complex formation and its interactions with the Ego1p-Ego3p complex and TORC1 components in yeast. Genes Cells 2014; 19:449-63. [PMID: 24702707 DOI: 10.1111/gtc.12145] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 02/12/2014] [Indexed: 01/10/2023]
Abstract
The yeast Ras-like GTPases Gtr1p and Gtr2p form a heterodimer, are implicated in the regulation of TOR complex 1 (TORC1) and play pivotal roles in cell growth. Gtr1p and Gtr2p bind Ego1p and Ego3p, which are tethered to the endosomal and vacuolar membranes where TORC1 functions are regulated through a relay of amino acid signaling interactions. The mechanisms by which Gtr1p and Gtr2p activate TORC1 remain obscure. We probed the interactions of the Gtr1p-Gtr2p complex with the Ego1p-Ego3p complex and TORC1 subunits. Mutations in the region (179-220 a.a.) following the nucleotide-binding region of Gtr1p and Gtr2p abrogated their mutual interaction and resulted in a loss in function, suggesting that complex formation between Gtr1p and Gtr2p was indispensable for TORC1 function. A modified yeast two-hybrid assay showed that Gtr1p-Gtr2p complex formation is important for its interaction with the Ego1p-Ego3p complex. GTP-bound Gtr1p interacted with the region containing the HEAT repeats of Kog1p and the C-terminal region of Tco89p. The GTP-bound Gtr2p suppressed a Kog1p mutation. Our findings indicate that the interactions of the Gtr1p-Gtr2p complex with the Ego1p-Ego3p complex and TORC1 components Kog1p and Tco89p play a role in TORC1 function.
Collapse
Affiliation(s)
- Takeshi Sekiguchi
- Department of Molecular Biology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | | | | | | | | |
Collapse
|
42
|
Nicolson GL, Ash ME. Lipid Replacement Therapy: a natural medicine approach to replacing damaged lipids in cellular membranes and organelles and restoring function. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:1657-79. [PMID: 24269541 DOI: 10.1016/j.bbamem.2013.11.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Revised: 10/30/2013] [Accepted: 11/09/2013] [Indexed: 12/14/2022]
Abstract
Lipid Replacement Therapy, the use of functional oral supplements containing cell membrane phospholipids and antioxidants, has been used to replace damaged, usually oxidized, membrane glycerophospholipids that accumulate during aging and in various clinical conditions in order to restore cellular function. This approach differs from other dietary and intravenous phospholipid interventions in the composition of phospholipids and their defense against oxidation during storage, ingestion, digestion and uptake as well as the use of protective molecules that noncovalently complex with phospholipid micelles and prevent their enzymatic and bile disruption. Once the phospholipids have been taken in by transport processes, they are protected by several natural mechanisms involving lipid receptors, transport and carrier molecules and circulating cells and lipoproteins until their delivery to tissues and cells where they can again be transferred to intracellular membranes by specific and nonspecific transport systems. Once delivered to membrane sites, they naturally replace and stimulate removal of damaged membrane lipids. Various chronic clinical conditions are characterized by membrane damage, mainly oxidative but also enzymatic, resulting in loss of cellular function. This is readily apparent in mitochondrial inner membranes where oxidative damage to phospholipids like cardiolipin and other molecules results in loss of trans-membrane potential, electron transport function and generation of high-energy molecules. Recent clinical trials have shown the benefits of Lipid Replacement Therapy in restoring mitochondrial function and reducing fatigue in aged subjects and patients with a variety of clinical diagnoses that are characterized by loss of mitochondrial function and include fatigue as a major symptom. This Article is Part of a Special Issue Entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.
Collapse
Affiliation(s)
- Garth L Nicolson
- Department of Molecular Pathology, The Institute for Molecular Medicine, Huntington Beach, CA 92649, USA.
| | - Michael E Ash
- Clinical Education, Newton Abbot, Devon TQ12 4SG, UK
| |
Collapse
|