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Gai Z, Hu S, He Y, Yan S, Wang R, Gong G, Zhao J. L-arginine alleviates heat stress-induced mammary gland injury through modulating CASTOR1-mTORC1 axis mediated mitochondrial homeostasis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:172017. [PMID: 38552976 DOI: 10.1016/j.scitotenv.2024.172017] [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: 01/22/2024] [Revised: 03/18/2024] [Accepted: 03/25/2024] [Indexed: 04/06/2024]
Abstract
As global warming intensifies, extreme heat is becoming increasingly frequent. These extreme heatwaves have decreased the milk production of dairy animals such as cows and goats and have caused significant damage to the entire dairy industry. It is known that heat stress (HS) can induce the apoptosis and autophagy of mammary epithelial cells (MECs), leading to a decrease in lactating MECs. L-arginine can effectively attenuate HS-induced decreases in milk yield, but the exact mechanisms are not fully understood. In this study, we found that HS upregulated the arginine sensor CASTOR1 in mouse MECs. Arginine activated mTORC1 activity through CASTOR1 and promoted mitochondrial biogenesis through the mTORC1/PGC-1α/NRF1 pathway. Moreover, arginine inhibited mitophagy through the CASTOR1/PINK1/Parkin pathway. Mitochondrial homeostasis ensures ATP synthesis and a stable cellular redox state for MECs under HS, further alleviating HS-induced damage and improving the lactation performance of MECs. In conclusion, these findings reveal the molecular mechanisms by which L-arginine relieves HS-induced mammary gland injury, and suggest that the intake of arginine-based feeds or feed additives is a promising method to increase the milk yield of dairy animals in extreme heat conditions.
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Affiliation(s)
- Zhongchao Gai
- School of Food Science & Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Songhao Hu
- School of Food Science & Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Yujiao He
- School of Food Science & Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Sijia Yan
- School of Food Science & Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Ranran Wang
- School of Food Science & Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Guoli Gong
- School of Food Science & Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
| | - Jieqiong Zhao
- Department of Cardiology, The Second Affiliated Hospital of Air Force Medical University, Xi'an 710038, China.
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2
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Yang C, Sun X, Wu G. New insights into GATOR2-dependent interactions and its conformational changes in amino acid sensing. Biosci Rep 2024; 44:BSR20240038. [PMID: 38372438 PMCID: PMC10938194 DOI: 10.1042/bsr20240038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 02/08/2024] [Accepted: 02/13/2024] [Indexed: 02/20/2024] Open
Abstract
Eukaryotic cells coordinate growth under different environmental conditions via mechanistic target of rapamycin complex 1 (mTORC1). In the amino-acid-sensing signalling pathway, the GATOR2 complex, containing five evolutionarily conserved subunits (WDR59, Mios, WDR24, Seh1L and Sec13), is required to regulate mTORC1 activity by interacting with upstream CASTOR1 (arginine sensor) and Sestrin2 (leucine sensor and downstream GATOR1 complex). GATOR2 complex utilizes β-propellers to engage with CASTOR1, Sestrin2 and GATOR1, removal of these β-propellers results in substantial loss of mTORC1 capacity. However, structural information regarding the interface between amino acid sensors and GATOR2 remains elusive. With the recent progress of the AI-based tool AlphaFold2 (AF2) for protein structure prediction, structural models were predicted for Sentrin2-WDR24-Seh1L and CASTOR1-Mios β-propeller. Furthermore, the effectiveness of relevant residues within the interface was examined using biochemical experiments combined with molecular dynamics (MD) simulations. Notably, fluorescence resonance energy transfer (FRET) analysis detected the structural transition of GATOR2 in response to amino acid signals, and the deletion of Mios β-propeller severely impeded that change at distinct arginine levels. These findings provide structural perspectives on the association between GATOR2 and amino acid sensors and can facilitate future research on structure determination and function.
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Affiliation(s)
- Can Yang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, the Joint International Research Laboratory of Metabolic and Developmental Sciences MOE, Shanghai Jiao Tong University, Shanghai, China
| | - Xuan Sun
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, the Joint International Research Laboratory of Metabolic and Developmental Sciences MOE, Shanghai Jiao Tong University, Shanghai, China
| | - Geng Wu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, the Joint International Research Laboratory of Metabolic and Developmental Sciences MOE, Shanghai Jiao Tong University, Shanghai, China
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3
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Khalil MI, Ali MM, Holail J, Houssein M. Growth or death? Control of cell destiny by mTOR and autophagy pathways. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2023; 185:39-55. [PMID: 37944568 DOI: 10.1016/j.pbiomolbio.2023.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/08/2023] [Accepted: 10/23/2023] [Indexed: 11/12/2023]
Abstract
One of the central regulators of cell growth, proliferation, and metabolism is the mammalian target of rapamycin, mTOR, which exists in two structurally and functionally different complexes: mTORC1 and mTORC2; unlike m TORC2, mTORC1 is activated in response to the sufficiency of nutrients and is inhibited by rapamycin. mTOR complexes have critical roles not only in protein synthesis, gene transcription regulation, proliferation, tumor metabolism, but also in the regulation of the programmed cell death mechanisms such as autophagy and apoptosis. Autophagy is a conserved catabolic mechanism in which damaged molecules are recycled in response to nutrient starvation. Emerging evidence indicates that the mTOR signaling pathway is frequently activated in tumors. In addition, dysregulation of autophagy was associated with the development of a variety of human diseases, such as cancer and aging. Since mTOR can inhibit the induction of the autophagic process from the early stages of autophagosome formation to the late stage of lysosome degradation, the use of mTOR inhibitors to regulate autophagy could be considered a potential therapeutic option. The present review sheds light on the mTOR and autophagy signaling pathways and the mechanisms of regulation of mTOR-autophagy.
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Affiliation(s)
- Mahmoud I Khalil
- Department of Biological Sciences, Faculty of Science, Beirut Arab University, Beirut, 11072809, Lebanon; Molecular Biology Unit, Department of Zoology, Faculty of Science, Alexandria University, Alexandria, 21511, Egypt.
| | - Mohamad M Ali
- Department of Medical Biochemistry and Microbiology, Science for Life Laboratory, Uppsala University, SE-751 23, Uppsala, Sweden.
| | - Jasmine Holail
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia; Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom.
| | - Marwa Houssein
- Department of Biological Sciences, Faculty of Science, Beirut Arab University, Beirut, 11072809, Lebanon.
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4
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Chen H, Guo Z, Sun Y, Dai X. The immunometabolic reprogramming of microglia in Alzheimer's disease. Neurochem Int 2023; 171:105614. [PMID: 37748710 DOI: 10.1016/j.neuint.2023.105614] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/08/2023] [Accepted: 09/14/2023] [Indexed: 09/27/2023]
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disorder (NDD). In the central nervous system (CNS), immune cells like microglia could reprogram intracellular metabolism to alter or exert cellular immune functions in response to environmental stimuli. In AD, microglia could be activated and differentiated into pro-inflammatory or anti-inflammatory phenotypes, and these differences in cellular phenotypes resulted in variance in cellular energy metabolism. Considering the enormous energy requirement of microglia for immune functions, the changes in mitochondria-centered energy metabolism and substrates of microglia are crucial for the cellular regulation of immune responses. Here we reviewed the mechanisms of microglial metabolic reprogramming by analyzing their flexible metabolic patterns and changes that occurred in their metabolism during the development of AD. Further, we summarized the role of drugs in modulating immunometabolic reprogramming to prevent neuroinflammation, which may shed light on a new research direction for AD treatment.
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Affiliation(s)
- Hongli Chen
- Beijing Key Laboratory of Bioactive Substances and Functional Food, College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China
| | - Zichen Guo
- Beijing Key Laboratory of Bioactive Substances and Functional Food, College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China
| | - Yaxuan Sun
- Beijing Key Laboratory of Bioactive Substances and Functional Food, College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China
| | - Xueling Dai
- Beijing Key Laboratory of Bioactive Substances and Functional Food, College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China.
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5
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Linde-Garelli KY, Rogala KB. Structural mechanisms of the mTOR pathway. Curr Opin Struct Biol 2023; 82:102663. [PMID: 37572585 DOI: 10.1016/j.sbi.2023.102663] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 07/01/2023] [Accepted: 07/07/2023] [Indexed: 08/14/2023]
Abstract
The mTOR signaling pathway is essential for regulating cell growth and mammalian metabolism. The mTOR kinase forms two complexes, mTORC1 and mTORC2, which respond to external stimuli and regulate differential downstream targets. Cellular membrane-associated translocation mediates function and assembly of the mTOR complexes, and recent structural studies have begun uncovering the molecular basis by which the mTOR pathway (1) regulates signaling inputs, (2) recruits substrates, (3) localizes to biological membranes, and (4) becomes activated. Moreover, indications of dysregulated mTOR signaling are implicated in a wide range of diseases and an increasingly comprehensive understanding of structural mechanisms is driving novel translational development.
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Affiliation(s)
- Karen Y Linde-Garelli
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Kacper B Rogala
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA.
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6
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Li B, Khan MZ, Khan IM, Ullah Q, Cisang ZM, Zhang N, Wu D, Huang B, Ma Y, Khan A, Jiang N, Zahoor M. Genetics, environmental stress, and amino acid supplementation affect lactational performance via mTOR signaling pathway in bovine mammary epithelial cells. Front Genet 2023; 14:1195774. [PMID: 37636261 PMCID: PMC10448190 DOI: 10.3389/fgene.2023.1195774] [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: 03/28/2023] [Accepted: 06/26/2023] [Indexed: 08/29/2023] Open
Abstract
Mammary glands are known for their ability to convert nutrients present in the blood into milk contents. In cows, milk synthesis and the proliferation of cow mammary epithelial cells (CMECs) are regulated by various factors, including nutrients such as amino acids and glucose, hormones, and environmental stress. Amino acids, in particular, play a crucial role in regulating cell proliferation and casein synthesis in mammalian epithelial cells, apart from being building blocks for protein synthesis. Studies have shown that environmental factors, particularly heat stress, can negatively impact milk production performance in dairy cattle. The mammalian target of rapamycin complex 1 (mTORC1) pathway is considered the primary signaling pathway involved in regulating cell proliferation and milk protein and fat synthesis in cow mammary epithelial cells in response to amino acids and heat stress. Given the significant role played by the mTORC signaling pathway in milk synthesis and cell proliferation, this article briefly discusses the main regulatory genes, the impact of amino acids and heat stress on milk production performance, and the regulation of mTORC signaling pathway in cow mammary epithelial cells.
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Affiliation(s)
- Bin Li
- Institute of Animal Husbandry and Veterinary, Tibet Autonomous Regional Academy of Agricultural Sciences, Lhasa, China
| | - Muhammad Zahoor Khan
- Liaocheng Research Institute of Donkey High‐Efficiency Breeding and Ecological Feeding, Agricultural Science and Engineering School, Liaocheng University, Liaocheng, China
- Faculty of Veterinary and Animal Sciences, The University of Agriculture, Dera Ismail Khan, Pakistan
| | - Ibrar Muhammad Khan
- Anhui Province Key Laboratory of Embryo Development and Reproduction Regulation, Anhui Province Key Laboratory of Environmental Hormone and Reproduction, School of Biological and Food Engineering, Fuyang Normal University, Fuyang, China
| | - Qudrat Ullah
- Faculty of Veterinary and Animal Sciences, The University of Agriculture, Dera Ismail Khan, Pakistan
| | - Zhuo-Ma Cisang
- Institute of Animal Husbandry and Veterinary, Tibet Autonomous Regional Academy of Agricultural Sciences, Lhasa, China
| | - Nan Zhang
- Tibet Autonomous Region Animal Husbandry Station, Lhasa, China
| | - Dan Wu
- Institute of Animal Husbandry and Veterinary, Tibet Autonomous Regional Academy of Agricultural Sciences, Lhasa, China
| | - Bingjian Huang
- Liaocheng Research Institute of Donkey High‐Efficiency Breeding and Ecological Feeding, Agricultural Science and Engineering School, Liaocheng University, Liaocheng, China
- College of Life Sciences, Liaocheng University, Liaocheng, China
| | - Yulin Ma
- State Key Laboratory of Animal Nutrition, Beijing Engineering Technology Research Center of Raw Milk Quality and Safety Control, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Adnan Khan
- Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Nan Jiang
- Institute of Animal Husbandry and Veterinary, Tibet Autonomous Regional Academy of Agricultural Sciences, Lhasa, China
| | - Muhammad Zahoor
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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Sung Y, Yu YC, Han JM. Nutrient sensors and their crosstalk. Exp Mol Med 2023; 55:1076-1089. [PMID: 37258576 PMCID: PMC10318010 DOI: 10.1038/s12276-023-01006-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 02/22/2023] [Accepted: 03/13/2023] [Indexed: 06/02/2023] Open
Abstract
The macronutrients glucose, lipids, and amino acids are the major components that maintain life. The ability of cells to sense and respond to fluctuations in these nutrients is a crucial feature for survival. Nutrient-sensing pathways are thus developed to govern cellular energy and metabolic homeostasis and regulate diverse biological processes. Accordingly, perturbations in these sensing pathways are associated with a wide variety of pathologies, especially metabolic diseases. Molecular sensors are the core within these sensing pathways and have a certain degree of specificity and affinity to sense the intracellular fluctuation of each nutrient either by directly binding to that nutrient or indirectly binding to its surrogate molecules. Once the changes in nutrient levels are detected, sensors trigger signaling cascades to fine-tune cellular processes for energy and metabolic homeostasis, for example, by controlling uptake, de novo synthesis or catabolism of that nutrient. In this review, we summarize the major discoveries on nutrient-sensing pathways and explain how those sensors associated with each pathway respond to intracellular nutrient availability and how these mechanisms control metabolic processes. Later, we further discuss the crosstalk between these sensing pathways for each nutrient, which are intertwined to regulate overall intracellular nutrient/metabolic homeostasis.
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Affiliation(s)
- Yulseung Sung
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon, 21983, South Korea
| | - Ya Chun Yu
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon, 21983, South Korea
| | - Jung Min Han
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon, 21983, South Korea.
- Department of Integrated OMICS for Biomedical Science, Yonsei University, Seoul, 03722, South Korea.
- POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, 37673, South Korea.
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8
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Influence of mTOR-regulated anabolic pathways on equine skeletal muscle health. J Equine Vet Sci 2023; 124:104281. [PMID: 36905972 DOI: 10.1016/j.jevs.2023.104281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/04/2023] [Accepted: 03/06/2023] [Indexed: 03/11/2023]
Abstract
Skeletal muscle is a highly dynamic organ that is essential for locomotion as well as endocrine regulation in all populations of horses. However, despite the importance of adequate muscle development and maintenance, the mechanisms underlying protein anabolism in horses on different diets, exercise programs, and at different life stages remain obscure. Mechanistic target of rapamycin (mTOR) is a key component of the protein synthesis pathway and is regulated by biological factors such as insulin and amino acid availability. Providing a diet ample in vital amino acids, such as leucine and glutamine, is essential in activating sensory pathways that recruit mTOR to the lysosome and assist in the translation of important downstream targets. When the diet is well balanced, mitochondrial biogenesis and protein synthesis are activated in response to increased exercise bouts in the performing athlete. It is important to note that the mTOR kinase pathways are multi-faceted and very complex, with several binding partners and targets that lead to specific functions in protein turnover of the cell, and ultimately, the capacity to maintain or grow muscle mass. Further, these pathways are likely altered across the lifespan, with an emphasis of growth in young horses while decreases in musculature with aged horses appears to be attributable to degradation or other regulators of protein synthesis rather than alterations in the mTOR pathway. Previous work has begun to pinpoint ways in which the mTOR pathway is influenced by diet, exercise, and age; however, future research is warranted to quantify the functional outcomes related to changes in mTOR. Promisingly, this could provide direction on appropriate management techniques to support skeletal muscle growth and maximize athletic potential in differing equine populations.
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Hu H, Lu X, Huang L, He Y, Liu X, Wang Y, Duan C. Castor1 overexpression regulates microglia M1/M2 polarization via inhibiting mTOR pathway. Metab Brain Dis 2023; 38:699-708. [PMID: 36454504 DOI: 10.1007/s11011-022-01135-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 11/24/2022] [Indexed: 12/05/2022]
Abstract
Microglia are resident immune cells in the brain and are closely associated with central nervous system inflammation and neurodegenerative diseases. It is known that mammalian target of rapamycin (mTOR) pathway plays an important role in the polarization of microglia. Castor1 has been identified as the cytosolic arginine sensor for the mTOR complex 1 (mTORC1) pathway, but the role of Castor1 in microglial polarization is still unknown. The purpose of this study was to explore the regulatory effect of Castor1 on microglial polarization and the underlying mechanism. The results demonstrated that Castor1 expression was significantly decreased in lipopolysaccharides (LPS) and interferon (IFN)-γ treated microglia. Castor1 overexpression inhibited the microglia M1 polarization by reducing the expression of M1 related markers. However, the expression of M2-related genes was promoted when Castor1 was overexpressed in IL-4 treated microglia. Mechanistically, Castor1 overexpression inhibited the activation of mTOR signaling pathway. In addition, after treatment with the mTOR activator MHY1485, the inhibitory effect of Castor1 overexpression on M1 polarization was attenuated, indicating that the regulation effects of Castor1 on M1 polarization was dependent on its inhibition of mTOR pathway. We propose that Castor1-mTOR signaling pathway could be considered as a potential target for treatment and intervention of central nervous system-related diseases by regulating microglia polarization.
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Affiliation(s)
- Huiling Hu
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
| | - Xiaoxia Lu
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Lisi Huang
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Yuqing He
- Translational Medicine Research Center, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Xiuli Liu
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Ying Wang
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
| | - Chaohui Duan
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
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10
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Wen H, Chen W, Chen Y, Wei G, Ni T. Integrative analysis of Iso-Seq and RNA-seq reveals dynamic changes of alternative promoter, alternative splicing and alternative polyadenylation during Angiotensin II-induced senescence in rat primary aortic endothelial cells. Front Genet 2023; 14:1064624. [PMID: 36741323 PMCID: PMC9892061 DOI: 10.3389/fgene.2023.1064624] [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: 10/12/2022] [Accepted: 01/10/2023] [Indexed: 01/21/2023] Open
Abstract
In eukaryotes, alternative promoter (AP), alternative splicing (AS), and alternative polyadenylation (APA) are three crucial regulatory mechanisms that modulate message RNA (mRNA) diversity. Although AP, AS and APA are involved in diverse biological processess, whether they have dynamic changes in Angiotensin II (Ang II) induced senescence in rat primary aortic endothelial cells (RAECs), an important cellular model for studying cardiovascular disease, remains unclear. Here we integrated both PacBio single-molecule long-read isoform sequencing (Iso-Seq) and Illumina short-read RNA sequencing (RNA-seq) to analyze the changes of AP, AS and APA in Ang II-induced senescent RAECs. Iso-Seq generated 36,278 isoforms from 10,145 gene loci and 65.81% of these isoforms are novel, which were further cross-validated by public data obtained by other techonologies such as CAGE, PolyA-Seq and 3'READS. APA contributed most to novel isoforms, followed by AS and AP. Further investigation showed that AP, AS and APA could all contribute to the regulation of isoform, but AS has more dynamic changes compared to AP and APA upon Ang II stimulation. Genes undergoing AP, AS and APA in Ang II-treated cells are enriched in various pathways related to aging or senescence, suggesting that these molecular changes are involved in functional alterations during Ang II-induced senescence. Together, the present study largely improved the annotation of rat genome and revealed gene expression changes at isoform level, extending the understanding of the complexity of gene regulation in Ang II-treated RAECs, and also provided novel clues for discovering the regulatory mechanism undelying Ang II caused vascular senescence and diseases.
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Affiliation(s)
- Haimei Wen
- Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Human Phenome Institute, Fudan University, Shanghai, China,Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Sciences, Fudan University, Shanghai, China
| | - Wei Chen
- Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Human Phenome Institute, Fudan University, Shanghai, China
| | - Yu Chen
- Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Human Phenome Institute, Fudan University, Shanghai, China
| | - Gang Wei
- Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Human Phenome Institute, Fudan University, Shanghai, China,Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Sciences, Fudan University, Shanghai, China,*Correspondence: Ting Ni, ; Gang Wei,
| | - Ting Ni
- Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Human Phenome Institute, Fudan University, Shanghai, China,*Correspondence: Ting Ni, ; Gang Wei,
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11
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Esen O, Rozwadowski K, Cepicka L, Gabrys T, Karayigit R. Practical Nutrition Strategies to Support Basketball Performance during International Short-Term Tournaments: A Narrative Review. Nutrients 2022; 14:nu14224909. [PMID: 36432595 PMCID: PMC9694551 DOI: 10.3390/nu14224909] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/10/2022] [Accepted: 11/16/2022] [Indexed: 11/22/2022] Open
Abstract
A short-term (e.g., 6 days) basketball tournament is a shorter version of international tournaments, and qualification in it enables participation in international tournaments such as the Olympics and World championships or preparation before major tournaments. Time for recovery between matches is shorter compared with major tournaments, resulting in an accentuated load on players, which can be repeated up to four times within the 6-day competition period. Therefore, nutritional strategies need to focus on faster and adequate recovery after each match as well as optimum fuelling and hydration before and during matches. Travelling can also create additional challenges when preparing and/or applying those nutritional strategies. There are some particular evidence-based sport foods and ergogenic aids that can improve intermittent activity and/or the execution of motor skills, which may facilitate basketball players' recovery and performance. The present review provides practical nutritional strategies to support short-term basketball tournaments based on players' physiological needs and current sport nutrition guidelines.
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Affiliation(s)
- Ozcan Esen
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle upon Tyne NE1 8ST, UK
- Correspondence:
| | | | - Ladislav Cepicka
- Department of Physical Education and Sport, Faculty of Education, University of West Bohemia, 30100 Pilsen, Czech Republic
| | - Tomasz Gabrys
- Department of Physical Education and Sport, Faculty of Education, University of West Bohemia, 30100 Pilsen, Czech Republic
| | - Raci Karayigit
- Faculty of Sport Sciences, Ankara University, Gölbaşı, Ankara 06830, Turkey
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12
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Tang X, Zhang Y, Wang G, Zhang C, Wang F, Shi J, Zhang T, Ding J. Molecular mechanism of S-adenosylmethionine sensing by SAMTOR in mTORC1 signaling. SCIENCE ADVANCES 2022; 8:eabn3868. [PMID: 35776786 PMCID: PMC10883374 DOI: 10.1126/sciadv.abn3868] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The mechanistic target of rapamycin-mLST8-raptor complex (mTORC1) functions as a central regulator of cell growth and metabolism in response to changes in nutrient signals such as amino acids. SAMTOR is an S-adenosylmethionine (SAM) sensor, which regulates the mTORC1 activity through its interaction with the GTPase-activating protein activity toward Rags-1 (GATOR1)-KPTN, ITFG2, C12orf66 and SZT2-containing regulator (KICSTOR) complex. In this work, we report the crystal structures of Drosophila melanogaster SAMTOR in apo form and in complex with SAM. SAMTOR comprises an N-terminal helical domain and a C-terminal SAM-dependent methyltransferase (MTase) domain. The MTase domain contains the SAM-binding site and the potential GATOR1-KICSTOR-binding site. The helical domain functions as a molecular switch, which undergoes conformational change upon SAM binding and thereby modulates the interaction of SAMTOR with GATOR1-KICSTOR. The functional roles of the key residues and the helical domain are validated by functional assays. Our structural and functional data together reveal the molecular mechanism of the SAM sensing of SAMTOR and its functional role in mTORC1 signaling.
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Affiliation(s)
- Xin Tang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
- School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, China
| | - Yifan Zhang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Guanchao Wang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Chunxiao Zhang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Fang Wang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Jiawen Shi
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University, Sixth People's Hospital of Nantong, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Nantong 226011, China
| | - Tianlong Zhang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University, Sixth People's Hospital of Nantong, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Nantong 226011, China
| | - Jianping Ding
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
- School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, China
- School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, 1 Xiangshan Road, Hangzhou 310024, China
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13
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Yue S, Li G, He S, Li T. The central role of mTORC1 in amino acid sensing. Cancer Res 2022; 82:2964-2974. [PMID: 35749594 DOI: 10.1158/0008-5472.can-21-4403] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 04/28/2022] [Accepted: 06/17/2022] [Indexed: 11/16/2022]
Abstract
The mechanistic target of rapamycin (mTOR) is a master regulator of cell growth that controls cell homeostasis in response to nutrients, growth factors, and other environmental cues. Recent studies have emphasized the importance of lysosomes as a hub for nutrient sensing, especially amino acid sensing by mTORC1. This review highlights recent advances in understanding the amino acid-mTORC1 signaling axis and the role of mTORC1 in cancer.
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14
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mTOR substrate phosphorylation in growth control. Cell 2022; 185:1814-1836. [PMID: 35580586 DOI: 10.1016/j.cell.2022.04.013] [Citation(s) in RCA: 101] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/05/2022] [Accepted: 04/07/2022] [Indexed: 12/20/2022]
Abstract
The target of rapamycin (TOR), discovered 30 years ago, is a highly conserved serine/threonine protein kinase that plays a central role in regulating cell growth and metabolism. It is activated by nutrients, growth factors, and cellular energy. TOR forms two structurally and functionally distinct complexes, TORC1 and TORC2. TOR signaling activates cell growth, defined as an increase in biomass, by stimulating anabolic metabolism while inhibiting catabolic processes. With emphasis on mammalian TOR (mTOR), we comprehensively reviewed the literature and identified all reported direct substrates. In the context of recent structural information, we discuss how mTORC1 and mTORC2, despite having a common catalytic subunit, phosphorylate distinct substrates. We conclude that the two complexes recruit different substrates to phosphorylate a common, minimal motif.
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15
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Gai Z, Wang Y, Wang J, Fu J, Tian L, Li X, Zhao J, Gong G. Downregulation of CASTOR1 Inhibits Heat-Stress-Induced Apoptosis and Promotes Casein and Lipid Synthesis in Mammary Epithelial Cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:5386-5395. [PMID: 35442666 DOI: 10.1021/acs.jafc.2c00877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Heat stress is one of the most important factors limiting the milk yields of dairy animals. This decline can be attributed to the heat-stress-induced apoptosis of mammary epithelial cells (MECs). The cytosolic arginine sensor for mTORC1 subunit 1 (CASTOR1) is a crucial upstream regulator of the mechanistic target of rapamycin complex 1 (mTORC1) signaling, which has close connections with apoptosis. However, the specific roles of CASTOR1 in regulating the apoptosis and lactation of MECs are still obscure. In the present study, we found that heat stress promotes apoptosis and CASTOR1's expression in HC11 cells. Downregulation of CASTOR1 inhibits heat-stress-induced apoptosis through a ROS-independent pathway. In addition, silencing of CASTOR1 promotes cell proliferation, cell cycle progression, and milk component synthesis, and overexpressing of CASTOR1 reverses these observations. Furthermore, we found that silencing of CASTOR1 contributes to the nuclear transport of SREBP1 and promotes lipid synthesis. This study demonstrates the pivotal roles of CASTOR1 in heat-stress-induced apoptosis and milk component synthesis in MECs.
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Affiliation(s)
- Zhongchao Gai
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, Shaanxi, China
| | - Yujiao Wang
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, Shaanxi, China
| | - Jie Wang
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, Shaanxi, China
| | - Jiapeng Fu
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, Shaanxi, China
| | - Lu Tian
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, Shaanxi, China
| | - Xue Li
- Department of Cardiology, The Second Affiliated Hospital of Air Force Medical University, Xi'an 710038, Shaanxi, China
| | - Jieqiong Zhao
- Department of Cardiology, The Second Affiliated Hospital of Air Force Medical University, Xi'an 710038, Shaanxi, China
| | - Guoli Gong
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, Shaanxi, China
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16
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Loissell-Baltazar YA, Dokudovskaya S. SEA and GATOR 10 Years Later. Cells 2021; 10:cells10102689. [PMID: 34685669 PMCID: PMC8534245 DOI: 10.3390/cells10102689] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/30/2021] [Accepted: 10/03/2021] [Indexed: 12/17/2022] Open
Abstract
The SEA complex was described for the first time in yeast Saccharomyces cerevisiae ten years ago, and its human homologue GATOR complex two years later. During the past decade, many advances on the SEA/GATOR biology in different organisms have been made that allowed its role as an essential upstream regulator of the mTORC1 pathway to be defined. In this review, we describe these advances in relation to the identification of multiple functions of the SEA/GATOR complex in nutrient response and beyond and highlight the consequence of GATOR mutations in cancer and neurodegenerative diseases.
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17
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Wang F, Zhao J, Zhang M, Yang J, Zeng G. Genome-wide analysis of the mouse LIM gene family reveals its roles in regulating pathological cardiac hypertrophy. FEBS Lett 2021; 595:2271-2289. [PMID: 34328660 DOI: 10.1002/1873-3468.14168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/27/2021] [Accepted: 07/17/2021] [Indexed: 11/08/2022]
Abstract
LIM-domain proteins have been shown to be associated with heart development and diseases. Systematic studies of LIM family members at the genome-wide level, which are crucial to further understand their functions in cardiac hypertrophy, are currently lacking. Here, 70 LIM genes were identified and characterised in mice. The expression patterns of LIM genes differ greatly during cardiac development and in the case of hypertrophy. Both Crip2 and Xirp2 are differentially expressed in cardiac hypertrophy and during heart failure. In addition, the hypertrophic state of cardiomyocytes is controlled by the relative expression levels of Crip2 and Xirp2. This study provides a foundation for further understanding of the special roles of LIM proteins in mammalian cardiac development and hypertrophy.
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Affiliation(s)
- Fangfang Wang
- Department of Cardiology, The Second Affiliated Hospital of Air Force Medical University, Xi'an, China
| | - Jieqiong Zhao
- Department of Cardiology, The Second Affiliated Hospital of Air Force Medical University, Xi'an, China
| | - Mingming Zhang
- Department of Cardiology, The Second Affiliated Hospital of Air Force Medical University, Xi'an, China
| | - Jingxiao Yang
- Department of Cardiology, The Second Affiliated Hospital of Air Force Medical University, Xi'an, China
| | - Guangwei Zeng
- Department of Cardiology, The Second Affiliated Hospital of Air Force Medical University, Xi'an, China
- Department of Cardiology, Xi'an International Medical Center Hospital, Northwest University, Xi'an, China
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18
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Seibert M, Kurrle N, Schnütgen F, Serve H. Amino acid sensory complex proteins in mTORC1 and macroautophagy regulation. Matrix Biol 2021; 100-101:65-83. [DOI: 10.1016/j.matbio.2021.01.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 01/02/2021] [Accepted: 01/02/2021] [Indexed: 12/15/2022]
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19
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Lee YS, Herrera-Tequia A, Silwal J, Geiger JH, Grotewold E. A hydrophobic residue stabilizes dimers of regulatory ACT-like domains in plant basic helix-loop-helix transcription factors. J Biol Chem 2021; 296:100708. [PMID: 33901489 PMCID: PMC8202348 DOI: 10.1016/j.jbc.2021.100708] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/20/2021] [Accepted: 04/22/2021] [Indexed: 11/12/2022] Open
Abstract
About a third of the plant basic helix–loop–helix (bHLH) transcription factors harbor a C-terminal aspartate kinase, chorismate mutase, and TyrA (ACT)-like domain, which was originally identified in the maize R regulator of anthocyanin biosynthesis, where it modulates the ability of the bHLH to dimerize and bind DNA. Characterization of other bHLH ACT-like domains, such as the one in the Arabidopsis R ortholog, GL3, has not definitively confirmed dimerization, raising the question of the overall role of this potential regulatory domain. To learn more, we compared the dimerization of the ACT-like domains of R (RACT) and GL3 (GL3ACT). We show that RACT dimerizes with a dissociation constant around 100 nM, over an order of magnitude stronger than GL3ACT. Structural predictions combined with mutational analyses demonstrated that V568, located in a hydrophobic pocket in RACT, is important: when mutated to the Ser residue present in GL3ACT, dimerization affinity dropped by almost an order of magnitude. The converse S595V mutation in GL3ACT significantly increased the dimerization strength. We cloned and assayed dimerization for all identified maize ACT-like domains and determined that 12 of 42 formed heterodimers in yeast two-hybrid assays, irrespective of whether they harbored V568, which was often replaced by other aliphatic amino acids. Moreover, we determined that the presence of polar residues at that position occurs only in a small subset of anthocyanin regulators. The combined results provide new insights into possibly regulatory mechanisms and suggest that many of the other plant ACT-like domains associate to modulate fundamental cellular processes.
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Affiliation(s)
- Yun Sun Lee
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Andres Herrera-Tequia
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Jagannath Silwal
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - James H Geiger
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Erich Grotewold
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan, USA.
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20
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Nesterov SV, Yaguzhinsky LS, Podoprigora GI, Nartsissov YR. Amino Acids as Regulators of Cell Metabolism. BIOCHEMISTRY (MOSCOW) 2021; 85:393-408. [PMID: 32569548 DOI: 10.1134/s000629792004001x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In this review, we discuss the principles of regulation and synchronization of metabolic processes in mammalian cells using a two-component model of cell metabolism consisting of a controlling signaling system that regulates major enzymatic cascades and executive metabolic system that directly performs biosynthetic reactions. This approach has allowed us to distinguish two transitional metabolic states (from catabolism to anabolism and vice versa) accompanied by major rearrangements in the signaling system. The signaling system of natural amino acids was selected, because amino acids are involved in both signaling and executive metabolic subsystems of general cell metabolism. We have developed a graphical representation of metabolic events that allowed us to demonstrate the succession of processes occurring in both metabolic subsystems during complete metabolic cycle in a non-dividing cell. An important revealed feature of the amino acid signaling system is that the signaling properties of amino acid are determined not only by their molecular structure, but also by the location within the cell. Four major signaling groups of amino acids have been identified that localize to lysosomes, mitochondria, cytosol, and extracellular space adjacent to the plasma membrane. Although these amino acids groups are similar in the composition, they have different receptors. We also proposed a scheme for the metabolism regulation by amino acids signaling that can serve as a basis for developing more complete spatio-temporal picture of metabolic regulation involving a wide variety of intracellular signaling cascades.
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Affiliation(s)
- S V Nesterov
- Institute of Cytochemistry and Molecular Pharmacology, Moscow, 115404, Russia.,Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - L S Yaguzhinsky
- Institute of Cytochemistry and Molecular Pharmacology, Moscow, 115404, Russia. .,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - G I Podoprigora
- Institute of Cytochemistry and Molecular Pharmacology, Moscow, 115404, Russia
| | - Ya R Nartsissov
- Institute of Cytochemistry and Molecular Pharmacology, Moscow, 115404, Russia
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21
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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: 108] [Impact Index Per Article: 27.0] [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.
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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
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22
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Liu B, Che Y, Zhang M, Ren W, Xia X, Liu H, Huang T, Huang J, Lei L. IFN-γ Activates the TLR4-CCL5 Signaling Through Reducing Arginine Level, Leading to Enhanced Susceptibility of Bovine Mammary Epithelial Cells to Staphylococcus aureus. Inflammation 2020; 43:2209-2221. [PMID: 32725514 DOI: 10.1007/s10753-020-01288-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Dairy cow mastitis is a common bacterial infectious disease which seriously threatens the development of the dairy cow industry. Previous studies have found that increased IFN-γ expression in dairy cows makes dairy cows more susceptible to mastitis, but the underlying mechanism is still not known. In this study, we utilized the in vitro bovine mammary epithelial cells (BMECs) model to explore the molecular mechanism via transcriptome sequencing technology, immunofluorescence, and Western blotting. It was found that IFN-γ promoted the adhesion and invasion of Staphylococcus aureus to BMECs through increasing the expression of TLR4-mediated CCL5 in BMECs. IFN-γ increased the activity of arginase II and reduced the level of arginine in cells, while the addition of arginine inhibited the expression of TLR4 and CCL5. An invasion experiment in mice further validated that IFN-γ treatment significantly increased the bacterial load in mammary glands and blood. However, the colonization and diffusion of S. aureus were interestingly decreased after Arg supplement. These data reveal that increased IFN-γ reduces arginine levels and activates TLR4-CCL5 signaling, leading to enhanced susceptibility of BMECs to S. aureus. Our findings are helpful to understand the pathogenesis of dairy cow mastitis and provide a theoretical basis for improvement of mastitis resistance in dairy cows.
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Affiliation(s)
- Baijun Liu
- College of Veterinary Medicine, Jilin University, Changchun, Xi'an Road 5333, China
| | - Yanyi Che
- College of Veterinary Medicine, Jilin University, Changchun, Xi'an Road 5333, China
| | - Meina Zhang
- College of Animal Science, Jilin University, Changchun, Jilin, China
| | - Wenbo Ren
- The First Hospital, Jilin University, Xinmin street 71, Changchun, China
| | - Xiaojing Xia
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China
| | - Hongtao Liu
- College of Veterinary Medicine, Jilin University, Changchun, Xi'an Road 5333, China
| | - Tinghao Huang
- College of Animal Science, Jilin University, Changchun, Jilin, China
| | - Jing Huang
- The First Hospital, Jilin University, Xinmin street 71, Changchun, China.
| | - Liancheng Lei
- College of Veterinary Medicine, Jilin University, Changchun, Xi'an Road 5333, China. .,College of Animal Sciences, Yangtze University, Jingzhou, China.
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23
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Zhao J, Wang Y, Li X, Gai Z. Genome-wide identification and characterization of Toll-like receptors (TLRs) in housefly (Musca domestica) and their roles in the insecticide resistance. Int J Biol Macromol 2020; 150:141-151. [DOI: 10.1016/j.ijbiomac.2020.02.061] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/03/2020] [Accepted: 02/07/2020] [Indexed: 02/06/2023]
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24
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Structural Analysis of an l-Cysteine Desulfurase from an Ssp DNA Phosphorothioation System. mBio 2020; 11:mBio.00488-20. [PMID: 32345643 PMCID: PMC7188994 DOI: 10.1128/mbio.00488-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Apart from its roles in Fe-S cluster assembly, tRNA thiolation, and sulfur-containing cofactor biosynthesis, cysteine desulfurase serves as a sulfur donor in the DNA PT modification, in which a sulfur atom substitutes a nonbridging oxygen in the DNA phosphodiester backbone. The initial sulfur mobilization from l-cysteine is catalyzed by the SspA cysteine desulfurase in the SspABCD-mediated DNA PT modification system. By determining the crystal structure of SspA, the study presents the molecular mechanism that SspA employs to recognize its cysteine substrate and PLP cofactor. To overcome the long distance (8.9 Å) between the catalytic Cys314 and the cysteine substrate, a conformational change occurs to bring Cys314 to the vicinity of the substrate, allowing for nucleophilic attack. DNA phosphorothioate (PT) modification, in which the nonbridging oxygen in the sugar-phosphate backbone is substituted by sulfur, is catalyzed by DndABCDE or SspABCD in a double-stranded or single-stranded manner, respectively. In Dnd and Ssp systems, mobilization of sulfur in PT formation starts with the activation of the sulfur atom of cysteine catalyzed by the DndA and SspA cysteine desulfurases, respectively. Despite playing the same biochemical role, SspA cannot be functionally replaced by DndA, indicating its unique physiological properties. In this study, we solved the crystal structure of Vibrio cyclitrophicus SspA in complex with its natural substrate, cysteine, and cofactor, pyridoxal phosphate (PLP), at a resolution of 1.80 Å. Our solved structure revealed the molecular mechanism that SspA employs to recognize its cysteine substrate and PLP cofactor, suggesting a common binding mode shared by cysteine desulfurases. In addition, although the distance between the catalytic Cys314 and the substrate cysteine is 8.9 Å, which is too far for direct interaction, our structural modeling and biochemical analysis revealed a conformational change in the active site region toward the cysteine substrate to move them close to each other to facilitate the nucleophilic attack. Finally, the pulldown analysis showed that SspA could form a complex with SspD, an ATP pyrophosphatase, suggesting that SspD might potentially accept the activated sulfur atom directly from SspA, providing further insights into the biochemical pathway of Ssp-mediated PT modification.
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25
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Gai Z, Zhao J. Genome-wide analysis reveals the functional and expressional correlation between RhoGAP and RhoGEF in mouse. Genomics 2020; 112:1694-1706. [DOI: 10.1016/j.ygeno.2019.09.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/21/2019] [Accepted: 09/17/2019] [Indexed: 12/17/2022]
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26
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Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) controls cell growth and metabolism in response to various environmental inputs, especially amino acids. In fact, the activity of mTORC1 is highly sensitive to changes in amino acid levels. Over past decades, a variety of proteins have been identified as participating in the mTORC1 pathway regulated by amino acids. Classically, the Rag guanosine triphosphatases (GTPases), which reside on the lysosome, transmit amino acid availability to the mTORC1 pathway and recruit mTORC1 to the lysosome upon amino acid sufficiency. Recently, several sensors of leucine, arginine, and S-adenosylmethionine for the amino acid-stimulated mTORC1 pathway have been coming to light. Characterization of these sensors is requisite for understanding how cells adjust amino acid sensing pathways to their different needs. In this review, we summarize recent advances in amino acid sensing mechanisms that regulate mTORC1 activity and highlight these identified sensors that accurately transmit specific amino acid signals to the mTORC1 pathway.
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Affiliation(s)
- Xiu-Zhi Li
- State Key Laboratory of Agricultural Microbiology, College of Animal Sciences and Technology, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China.,Hubei Provincial Engineering Laboratory for Pig Precision Feeding and Feed Safety Technology, Wuhan 430070, China
| | - Xiang-Hua Yan
- State Key Laboratory of Agricultural Microbiology, College of Animal Sciences and Technology, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China.,Hubei Provincial Engineering Laboratory for Pig Precision Feeding and Feed Safety Technology, Wuhan 430070, China
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27
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Iffland PH, Carson V, Bordey A, Crino PB. GATORopathies: The role of amino acid regulatory gene mutations in epilepsy and cortical malformations. Epilepsia 2019; 60:2163-2173. [PMID: 31625153 PMCID: PMC7155771 DOI: 10.1111/epi.16370] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 09/20/2019] [Accepted: 09/20/2019] [Indexed: 12/11/2022]
Abstract
The mechanistic target of rapamycin (mTOR) pathway has been implicated in a growing number of malformations of cortical development (MCD) associated with intractable epilepsy. Mutations in single genes encoding mTOR pathway regulatory proteins have been linked to MCD such as focal cortical dysplasia (FCD) types IIa and IIb, hemimegalencephaly (HME), and megalencephaly. Recent studies have demonstrated that the GATOR1 protein complex, comprised of DEPDC5, NPRL3, and NPRL2, plays a pivotal role in regulating mTOR signaling in response to cellular amino acid levels and that mutations in DEPDC5, NPRL3, or NPRL2 are linked to FCD, HME, and seizures. Histopathological analysis of FCD and HME tissue specimens resected from individuals harboring DEPDC5, NPRL3, or NPRL2 gene mutations reveals hyperactivation of mTOR pathway signaling. Family pedigrees carrying mutations in either DEPDC5 or NPRL3 share clinical phenotypes of epilepsy and MCD, as well as intellectual and neuropsychiatric disabilities. Interestingly, some individuals with seizures associated with DEPDC5, NPRL3, or NPRL2 variants exhibit normal brain imaging suggesting either occult MCD or a role for these genes in non-lesional neocortical epilepsy. Mouse models resulting from knockdown or knockout of either Depdc5 or Nprl3 exhibit altered cortical lamination, neuronal dysmorphogenesis, and enhanced neuronal excitability as reported in models resulting from direct mTOR activation through expression of its canonical activator RHEB. The role of the GATOR1 proteins in regulating mTOR signaling suggest plausible options for mTOR inhibition in the treatment of epilepsy associated with mutations in DEPDC5, NPRL3, or NPRL2.
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Affiliation(s)
- Philip H. Iffland
- Department of Neurology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Vincent Carson
- The Clinic for Special Children, Strasburg, Pennsylvania
| | - Angelique Bordey
- Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut
| | - Peter B. Crino
- Department of Neurology, University of Maryland School of Medicine, Baltimore, Maryland
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28
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Zhou Y, Wang C, Xiao Q, Guo L. Crystal structures of arginine sensor CASTOR1 in arginine-bound and ligand free states. Biochem Biophys Res Commun 2018; 508:387-391. [PMID: 30503338 DOI: 10.1016/j.bbrc.2018.11.147] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 11/21/2018] [Indexed: 02/05/2023]
Abstract
The mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) is a master regulator of metabolism and cell growth. Among the numerous extracellular and intracellular signals, certain amino acids activate mTORC1 in a Rag-dependent manner. Arginine can stimulate mTORC1 activity by releasing the inhibitor CASTOR1 (Cellular Arginine Sensor of mTORC1) from GATOR2, a positive regulator of mTORC1 which interacts with GATOR1, the GAP for RagA/B. Three groups have resolved the structures of arginine-CASTOR1 complex, shedding a new light on molecular basis of the regulation of mTORC1 activity by arginine. However, lacking the apo structure of CASTOR1 prelimited the molecular understanding of mechanism underlying mTORC1 regulation. Here, we report crystal structures of arginine sensor CASTOR1 in arginine-bound and ligand free states at 2.05 Å and 2.8 Å, respectively. Structural comparison of CASTOR1 between two states reveals near identical conformations, except in two loop regions. It indicates CASTOR1 does not undergo large conformational change during arginine binding. Therefore, we conclude a detailed structural interpretation of arginine sensing by CASTOR1 in mTORC1 pathway.
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Affiliation(s)
- Yanxia Zhou
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Chen Wang
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Qingjie Xiao
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Li Guo
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China.
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Selected In-Season Nutritional Strategies to Enhance Recovery for Team Sport Athletes: A Practical Overview. Sports Med 2018; 47:2201-2218. [PMID: 28702900 PMCID: PMC5633631 DOI: 10.1007/s40279-017-0759-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Team sport athletes face a variety of nutritional challenges related to recovery during the competitive season. The purpose of this article is to review nutrition strategies related to muscle regeneration, glycogen restoration, fatigue, physical and immune health, and preparation for subsequent training bouts and competitions. Given the limited opportunities to recover between training bouts and games throughout the competitive season, athletes must be deliberate in their recovery strategy. Foundational components of recovery related to protein, carbohydrates, and fluid have been extensively reviewed and accepted. Micronutrients and supplements that may be efficacious for promoting recovery include vitamin D, omega-3 polyunsaturated fatty acids, creatine, collagen/vitamin C, and antioxidants. Curcumin and bromelain may also provide a recovery benefit during the competitive season but future research is warranted prior to incorporating supplemental dosages into the athlete's diet. Air travel poses nutritional challenges related to nutrient timing and quality. Incorporating strategies to consume efficacious micronutrients and ingredients is necessary to support athlete recovery in season.
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ACR11 modulates levels of reactive oxygen species and salicylic acid-associated defense response in Arabidopsis. Sci Rep 2018; 8:11851. [PMID: 30087396 PMCID: PMC6081435 DOI: 10.1038/s41598-018-30304-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 07/27/2018] [Indexed: 01/10/2023] Open
Abstract
The ACT domain (aspartate kinase, chorismate mutase and TyrA), an allosteric effector binding domain, is commonly found in amino acid metabolic enzymes. In addition to ACT domain-containing enzymes, plants have a novel family of ACT domain repeat (ACR) proteins, which do not contain any recognizable catalytic domain. Arabidopsis has 12 ACR proteins, whose functions are largely unknown. To study the functions of Arabidopsis ACR11, we have characterized two independent T-DNA insertion mutants, acr11-2 and acr11-3. RNA gel-blot analysis revealed that the expression of wild-type ACR11 transcripts was not detectable in the acr11 mutants. Interestingly, a lesion-mimic phenotype occurs in some rosette leaves of the acr11 mutants. In addition, high levels of reactive oxygen species (ROS), salicylic acid (SA), and callose accumulate in the mutant leaves when grown under normal conditions. The expression of several SA marker genes and the key SA biosynthetic gene ISOCHORISMATE SYNTHASE1 is up-regulated in the acr11 mutants. Furthermore, the acr11 mutants are more resistant to the infection of bacterial pathogen Pseudomonas syringae pathovar tomato DC3000. These results suggest that ACR11 may be directly or indirectly involved in the regulation of ROS and SA accumulation, which in turn modulates SA-associated defense responses and disease resistance in Arabidopsis.
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Abstract
Background The protein kinase Target Of Rapamycin (TOR) is a nexus for the regulation of eukaryotic cell growth. TOR assembles into one of two distinct signalling complexes, TOR complex 1 (TORC1) and TORC2 (mTORC1/2 in mammals), with a set of largely non-overlapping protein partners. (m)TORC1 activation occurs in response to a series of stimuli relevant to cell growth, including nutrient availability, growth factor signals and stress, and regulates much of the cell's biosynthetic activity, from proteins to lipids, and recycling through autophagy. mTORC1 regulation is of great therapeutic significance, since in humans many of these signalling complexes, alongside subunits of mTORC1 itself, are implicated in a wide variety of pathophysiologies, including multiple types of cancer, neurological disorders, neurodegenerative diseases and metabolic disorders including diabetes. Methodology Recent years have seen numerous structures determined of (m)TOR, which have provided mechanistic insight into (m)TORC1 activation in particular, however the integration of cellular signals occurs upstream of the kinase and remains incompletely understood. Here we have collected and analysed in detail as many as possible of the molecular and structural studies which have shed light on (m)TORC1 repression, activation and signal integration. Conclusions A molecular understanding of this signal integration pathway is required to understand how (m)TORC1 activation is reconciled with the many diverse and contradictory stimuli affecting cell growth. We discuss the current level of molecular understanding of the upstream components of the (m)TORC1 signalling pathway, recent progress on this key biochemical frontier, and the future studies necessary to establish a mechanistic understanding of this master-switch for eukaryotic cell growth.
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Affiliation(s)
- Kailash Ramlaul
- Section of Structural Biology, Department of Medicine, Imperial College London, SW7 2AZ, UK
| | - Christopher H S Aylett
- Section of Structural Biology, Department of Medicine, Imperial College London, SW7 2AZ, UK
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Feller A, Yuan L, Grotewold E. The BIF Domain in Plant bHLH Proteins Is an ACT-Like Domain. THE PLANT CELL 2017; 29:1800-1802. [PMID: 28747421 PMCID: PMC5590504 DOI: 10.1105/tpc.17.00356] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/09/2017] [Accepted: 07/26/2017] [Indexed: 05/16/2023]
Affiliation(s)
- Antje Feller
- Center for Plant Molecular Biology-ZMBP,Developmental Genetics,University of Tuebingen,72076 Tuebingen, Germany
| | - Ling Yuan
- Department of Plant and Soil Sciences,University of Kentucky,Lexington, Kentucky 40546
- South China Botanical Garden,Guangzhou, China 510650
| | - Erich Grotewold
- Center for Applied Plant Sciences andDepartment of Molecular Genetics,The Ohio State University,Columbus, Ohio 43210
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Yao Y, Jones E, Inoki K. Lysosomal Regulation of mTORC1 by Amino Acids in Mammalian Cells. Biomolecules 2017; 7:biom7030051. [PMID: 28686218 PMCID: PMC5618232 DOI: 10.3390/biom7030051] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/03/2017] [Accepted: 07/04/2017] [Indexed: 12/15/2022] Open
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) is a master regulator of cell growth in eukaryotic cells. The active mTORC1 promotes cellular anabolic processes including protein, pyrimidine, and lipid biosynthesis, and inhibits catabolic processes such as autophagy. Consistent with its growth-promoting functions, hyper-activation of mTORC1 signaling is one of the important pathomechanisms underlying major human health problems including diabetes, neurodegenerative disorders, and cancer. The mTORC1 receives multiple upstream signals such as an abundance of amino acids and growth factors, thus it regulates a wide range of downstream events relevant to cell growth and proliferation control. The regulation of mTORC1 by amino acids is a fast-evolving field with its detailed mechanisms currently being revealed as the precise picture emerges. In this review, we summarize recent progress with respect to biochemical and biological findings in the regulation of mTORC1 signaling on the lysosomal membrane by amino acids.
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Affiliation(s)
- Yao Yao
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109, USA.
| | - Edith Jones
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109, USA.
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, 1137 East Catherine Street, Ann Arbor, MI 48109, USA.
| | - Ken Inoki
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109, USA.
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, 1137 East Catherine Street, Ann Arbor, MI 48109, USA.
- Department of Internal Medicine, University of Michigan Medical School, 1500 East Medical enter Drive, Ann Arbor, MI 48109, USA.
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The Architecture of the Rag GTPase Signaling Network. Biomolecules 2017; 7:biom7030048. [PMID: 28788436 PMCID: PMC5618229 DOI: 10.3390/biom7030048] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 06/22/2017] [Accepted: 06/27/2017] [Indexed: 12/11/2022] Open
Abstract
The evolutionarily conserved target of rapamycin complex 1 (TORC1) couples an array of intra- and extracellular stimuli to cell growth, proliferation and metabolism, and its deregulation is associated with various human pathologies such as immunodeficiency, epilepsy, and cancer. Among the diverse stimuli impinging on TORC1, amino acids represent essential input signals, but how they control TORC1 has long remained a mystery. The recent discovery of the Rag GTPases, which assemble as heterodimeric complexes on vacuolar/lysosomal membranes, as central elements of an amino acid signaling network upstream of TORC1 in yeast, flies, and mammalian cells represented a breakthrough in this field. Here, we review the architecture of the Rag GTPase signaling network with a special focus on structural aspects of the Rag GTPases and their regulators in yeast and highlight both the evolutionary conservation and divergence of the mechanisms that control Rag GTPases.
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