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Hussain MS, Moglad E, Afzal M, Gupta G, Hassan Almalki W, Kazmi I, Alzarea SI, Kukreti N, Gupta S, Kumar D, Chellappan DK, Singh SK, Dua K. Non-coding RNA mediated regulation of PI3K/Akt pathway in hepatocellular carcinoma: Therapeutic perspectives. Pathol Res Pract 2024; 258:155303. [PMID: 38728793 DOI: 10.1016/j.prp.2024.155303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 04/07/2024] [Accepted: 04/08/2024] [Indexed: 05/12/2024]
Abstract
Hepatocellular carcinoma (HCC) is among the primary reasons for fatalities caused by cancer globally, highlighting the need for comprehensive knowledge of its molecular aetiology to develop successful treatment approaches. The PI3K/Akt system is essential in the course of HCC, rendering it an intriguing candidate for treatment. Non-coding RNAs (ncRNAs), such as long ncRNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), are important mediators of the PI3K/Akt network in HCC. The article delves into the complex regulatory functions of ncRNAs in influencing the PI3K/Akt system in HCC. The study explores how lncRNAs, miRNAs, and circRNAs impact the expression as well as the function of the PI3K/Akt network, either supporting or preventing HCC growth. Additionally, treatment strategies focusing on ncRNAs in HCC are examined, such as antisense oligonucleotide-based methods, RNA interference, and small molecule inhibitor technologies. Emphasizing the necessity of ensuring safety and effectiveness in clinical settings, limitations, and future approaches in using ncRNAs as therapies for HCC are underlined. The present study offers useful insights into the complex regulation system of ncRNAs and the PI3K/Akt cascade in HCC, suggesting possible opportunities for developing innovative treatment approaches to address this lethal tumor.
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Affiliation(s)
- Md Sadique Hussain
- School of Pharmaceutical Sciences, Jaipur National University, Jagatpura, Jaipur, Rajasthan 302017, India
| | - Ehssan Moglad
- Department of Pharmaceutics, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al Kharj 11942, Saudi Arabia
| | - Muhammad Afzal
- Department of Pharmaceutical Sciences, Pharmacy Program, Batterjee Medical College, P.O. Box 6231, Jeddah 21442, Saudi Arabia
| | - Gaurav Gupta
- Centre for Global Health Research, Saveetha Medical College, Saveetha Institute of Medical and Technical Sciences, Saveetha University, India; Centre of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates.
| | - Waleed Hassan Almalki
- Department of Pharmacology, College of Pharmacy, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Imran Kazmi
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, 21589, Jeddah, Saudi Arabia
| | - Sami I Alzarea
- Department of Pharmacology, College of Pharmacy, Jouf University, 72341, Sakaka, Aljouf, Saudi Arabia
| | - Neelima Kukreti
- School of Pharmacy, Graphic Era Hill University, Dehradun 248007, India
| | - Saurabh Gupta
- Chameli Devi Institute of Pharmacy, Department of Pharmacology, Khandwa Road, Village Umrikheda, Near Toll Booth, Indore, Madhya Pradesh 452020, India
| | - Dinesh Kumar
- School of Pharmacy, Chitkara University, Himachal Pradesh, India
| | - Dinesh Kumar Chellappan
- Department of Life Sciences, School of Pharmacy, International Medical University, Kuala Lumpur, Malaysia
| | - Sachin Kumar Singh
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab 144411, India; Faculty of Health, Australian Research Centre in Complementary and Integrative Medicine, University of Technology Sydney, Ultimo, Australia; School of Medical and Life Sciences, Sunway University, 47500 Sunway City, Malaysia
| | - Kamal Dua
- Faculty of Health, Australian Research Centre in Complementary and Integrative Medicine, University of Technology Sydney, Ultimo, Australia; Discipline of Pharmacy, Graduate School of Health, University of Technology Sydney, NSW 2007, Australia; Uttaranchal Institute of Pharmaceutical Sciences, Uttaranchal University, Dehradun, India.
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Li K, Cao JF, Gong Y, Xiong L, Wu M, Qi Y, Ying X, Liu D, Ma X, Zhang X. Rapamycin improves the survival of epilepsy model cells by blocking phosphorylation of mTOR base on computer simulations and cellular experiments. Neurochem Int 2024; 176:105746. [PMID: 38641027 DOI: 10.1016/j.neuint.2024.105746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/08/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
PURPOSE Epilepsy is a chronic brain dysfunction characterized by recurrent epileptic seizures. Rapamycin is a naturally occurring macrolide from Streptomyces hygroscopicus, and rapamycin may provide a protective effect on the nervous system by affecting mTOR. Therefore, we investigated the pharmacologic mechanism of rapamycin treating epilepsy through bioinformatics analysis, cellular experiments and supercomputer simulation. METHODS Bioinformatics analysis was used to analyze targets of rapamycin treating epilepsy. We established epilepsy cell model by HT22 cells. RT-qPCR, WB and IF were used to verify the effects of rapamycin on mTOR at gene level and protein level. Computer simulations were used to model and evaluate the stability of rapamycin binding to mTOR protein. RESULTS Bioinformatics indicated mTOR played an essential role in signaling pathways of cell growth and cell metabolism. Cellular experiments showed that rapamycin could promote cell survival, and rapamycin did not have an effect on mRNA expression of mTOR. However, rapamycin was able to significantly inhibit the phosphorylation of mTOR at protein level. Computer simulations indicated that rapamycin was involved in the treatment of epilepsy through regulating phosphorylation of mTOR at protein level. CONCLUSION We found that rapamycin was capable of promoting the survival of epilepsy cells by inhibiting the phosphorylation of mTOR at protein level, and rapamycin did not have an effect on mRNA expression of mTOR. In addition to the traditional study that rapamycin affects mTORC1 complex by acting on FKBP12, this study found rapamycin could also directly block the phosphorylation of mTOR, therefore affecting the assembly of mTORC1 complex and mTOR signaling pathway.
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Affiliation(s)
- Kezhou Li
- College of Medicine, Southwest Jiaotong University, Chengdu, China; Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu, China
| | - Jun-Feng Cao
- Chengdu Medical College, Chengdu, China; College of Medicine, Southwest Jiaotong University, Chengdu, China
| | | | - Li Xiong
- Chengdu Medical College, Chengdu, China
| | - Mei Wu
- Chengdu Medical College, Chengdu, China
| | - Yue Qi
- Chengdu Medical College, Chengdu, China
| | | | | | - Xuntai Ma
- Chengdu Medical College, Chengdu, China; The First Affiliated Hospital of Clinical Medical College of Chengdu Medical College, Chengdu, China.
| | - Xiao Zhang
- Chengdu Medical College, Chengdu, China.
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Hernández-Esquivel AA, Torres-Olmos JA, Méndez-Gómez M, Castro-Mercado E, Flores-Cortéz I, Peña-Uribe CA, Campos-García J, López-Bucio J, Reyes-de la Cruz H, Valencia-Cantero E, García-Pineda E. Hydrogen peroxide modulates the expression of the target of rapamycin (TOR) and cell division in Arabidopsis thaliana. PROTOPLASMA 2024:10.1007/s00709-024-01959-6. [PMID: 38802622 DOI: 10.1007/s00709-024-01959-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 05/15/2024] [Indexed: 05/29/2024]
Abstract
Hydrogen peroxide (H2O2) is naturally produced by plant cells during normal development and serves as a messenger that regulates cell metabolism. Despite its importance, the relationship between hydrogen peroxide and the target of rapamycin (TOR) pathway, as well as its impact on cell division, has been poorly analyzed. In this study, we explore the interaction of H2O2 with TOR, a serine/threonine protein kinase that plays a central role in controlling cell growth, size, and metabolism in Arabidopsis thaliana. By applying two concentrations of H2O2 exogenously (0.5 and 1 mM), we could correlate developmental traits, such as primary root growth, lateral root formation, and fresh weight, with the expression of the cell cycle gene CYCB1;1, as well as TOR expression. When assessing the expression of the ribosome biogenesis-related gene RPS27B, an increase of 94.34% was noted following exposure to 1 mM H2O2 treatment. This increase was suppressed by the TOR inhibitor torin 2. The elimination of H2O2 accumulation with ascorbic acid (AA) resulted in decreased cell division as well as TOR expression. The potential molecular mechanisms associated with the effects of H2O2 on the cell cycle and TOR expression in roots are discussed in the context of the results.
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Affiliation(s)
- Alma Alejandra Hernández-Esquivel
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Jorge Alejandro Torres-Olmos
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Manuel Méndez-Gómez
- Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), Unidad Irapuato, 36821, Irapuato, Gto., México
| | - Elda Castro-Mercado
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Idolina Flores-Cortéz
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - César Arturo Peña-Uribe
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Jesús Campos-García
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - José López-Bucio
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Homero Reyes-de la Cruz
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Eduardo Valencia-Cantero
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Ernesto García-Pineda
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México.
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Chen Y, Zhang Y, Duo S, Liu W, Luo B. Study on the regulatory mechanism of latent membrane protein 2A on GCNT3 expression in nasopharyngeal carcinoma. Virus Genes 2024:10.1007/s11262-024-02071-w. [PMID: 38739247 DOI: 10.1007/s11262-024-02071-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 04/06/2024] [Indexed: 05/14/2024]
Abstract
O-Glycan synthesis enzyme glucosaminyl (N-acetyl) transferase 3 (GCNT3) is closely related to the occurrence and development of various cancers. However, the regulatory mechanism and function of GCNT3 in nasopharyngeal carcinoma (NPC) are still poorly understood. This study aims to explore the regulatory mechanism of EBV-encoded latent membrane protein 2A (LMP2A) on GCNT3 and the biological role of GCNT3 in NPC. The results show that LMP2A can activate GCNT3 through the mTORC1 pathway, and there is a positive feedback between the mTORC1 and GCNT3. GCNT3 regulates EMT progression by forming a complex with ZEB1 to promote cell migration. GCNT3 can also promote cell proliferation. These findings indicate that targeting the LMP2A-mTORC1-GCNT3 axis may represent a novel therapeutic target in NPC.
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Affiliation(s)
- Yijing Chen
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China
- Department of Clinical Laboratory, The Sixth Hospital of Wuhan, Affiliated Hospital of Jianghan University, Wuhan, China
| | - Yan Zhang
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China
- Department of Clinical Laboratory, Central Hospital of Zibo, Zibo, China
| | - Shi Duo
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Wen Liu
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China.
| | - Bing Luo
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China.
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Scepanovic G, Fernandez-Gonzalez R. Should I shrink or should I grow: cell size changes in tissue morphogenesis. Genome 2024; 67:125-138. [PMID: 38198661 DOI: 10.1139/gen-2023-0091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Cells change shape, move, divide, and die to sculpt tissues. Common to all these cell behaviours are cell size changes, which have recently emerged as key contributors to tissue morphogenesis. Cells can change their mass-the number of macromolecules they contain-or their volume-the space they encompass. Changes in cell mass and volume occur through different molecular mechanisms and at different timescales, slow for changes in mass and rapid for changes in volume. Therefore, changes in cell mass and cell volume, which are often linked, contribute to the development and shaping of tissues in different ways. Here, we review the molecular mechanisms by which cells can control and alter their size, and we discuss how changes in cell mass and volume contribute to tissue morphogenesis. The role that cell size control plays in developing embryos is only starting to be elucidated. Research on the signals that control cell size will illuminate our understanding of the cellular and molecular mechanisms that drive tissue morphogenesis.
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Affiliation(s)
- Gordana Scepanovic
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
- Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Rodrigo Fernandez-Gonzalez
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
- Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
- Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, ON, M5G 1X8, Canada
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Feng R, Liu F, Li R, Zhou Z, Lin Z, Lin S, Deng S, Li Y, Nong B, Xia Y, Li Z, Zhong X, Yang S, Wan G, Ma W, Wu S, Songyang Z. The rapid proximity labeling system PhastID identifies ATP6AP1 as an unconventional GEF for Rheb. Cell Res 2024; 34:355-369. [PMID: 38448650 PMCID: PMC11061317 DOI: 10.1038/s41422-024-00938-z] [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: 09/10/2023] [Accepted: 02/02/2024] [Indexed: 03/08/2024] Open
Abstract
Rheb is a small G protein that functions as the direct activator of the mechanistic target of rapamycin complex 1 (mTORC1) to coordinate signaling cascades in response to nutrients and growth factors. Despite extensive studies, the guanine nucleotide exchange factor (GEF) that directly activates Rheb remains unclear, at least in part due to the dynamic and transient nature of protein-protein interactions (PPIs) that are the hallmarks of signal transduction. Here, we report the development of a rapid and robust proximity labeling system named Pyrococcus horikoshii biotin protein ligase (PhBPL)-assisted biotin identification (PhastID) and detail the insulin-stimulated changes in Rheb-proximity protein networks that were identified using PhastID. In particular, we found that the lysosomal V-ATPase subunit ATP6AP1 could dynamically interact with Rheb. ATP6AP1 could directly bind to Rheb through its last 12 amino acids and utilizes a tri-aspartate motif in its highly conserved C-tail to enhance Rheb GTP loading. In fact, targeting the ATP6AP1 C-tail could block Rheb activation and inhibit cancer cell proliferation and migration. Our findings highlight the versatility of PhastID in mapping transient PPIs in live cells, reveal ATP6AP1's role as an unconventional GEF for Rheb, and underscore the importance of ATP6AP1 in integrating mTORC1 activation signals through Rheb, filling in the missing link in Rheb/mTORC1 activation.
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Affiliation(s)
- Ran Feng
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Feng Liu
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China.
| | - Ruofei Li
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zhifen Zhou
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zhuoheng Lin
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Song Lin
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Shengcheng Deng
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yingying Li
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Baoting Nong
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Ying Xia
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zhiyi Li
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xiaoqin Zhong
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Shuhan Yang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Gang Wan
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Wenbin Ma
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Su Wu
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.
| | - Zhou Songyang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou, Guangdong, China.
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.
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Roy M, Mbous Nguimbus L, Badiane PY, Goguen-Couture V, Degrandmaison J, Parent JL, Brunet MA, Roux S. Galectin-8 modulates human osteoclast activity partly through isoform-specific interactions. Life Sci Alliance 2024; 7:e202302348. [PMID: 38395460 PMCID: PMC10895193 DOI: 10.26508/lsa.202302348] [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: 08/30/2023] [Revised: 02/12/2024] [Accepted: 02/13/2024] [Indexed: 02/25/2024] Open
Abstract
In overactive human osteoclasts, we previously identified an alternative splicing event in LGALS8, encoding galectin-8, resulting in decreased expression of the long isoform. Galectin-8, which modulates cell-matrix interactions and functions intracellularly as a danger recognition receptor, has never been associated with osteoclast biology. In human osteoclasts, inhibition of galectin-8 expression revealed its roles in bone resorption, osteoclast nuclearity, and mTORC1 signaling regulation. Galectin-8 isoform-specific inhibition asserted a predominant role for the short isoform in bone resorption. Moreover, a liquid chromatography with tandem mass spectrometry (LC-MS/MS) proteomic analysis of galectin-8 isoforms performed in HEK293T cells identified 22 proteins shared by both isoforms. Meanwhile, nine interacting partners were specific for the short isoform, and none were unique to the long isoform. Interactors specific for the galectin-8 short isoform included cell adhesion proteins and lysosomal proteins. We confirmed the interactions of galectin-8 with CLCN3, CLCN7, LAMP1, and LAMP2, all known to localize to secretory vesicles, in human osteoclasts. Altogether, our study reveals direct roles of galectin-8 in osteoclast activity, mostly attributable to the short isoform.
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Affiliation(s)
- Michèle Roy
- https://ror.org/00kybxq39 Division of Rheumatology, Department of Medicine, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Léopold Mbous Nguimbus
- https://ror.org/00kybxq39 Division of Rheumatology, Department of Medicine, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Papa Yaya Badiane
- https://ror.org/00kybxq39 Division of Rheumatology, Department of Medicine, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Victor Goguen-Couture
- https://ror.org/00kybxq39 Division of Rheumatology, Department of Medicine, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Jade Degrandmaison
- https://ror.org/00kybxq39 Division of Rheumatology, Department of Medicine, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Jean-Luc Parent
- https://ror.org/00kybxq39 Division of Rheumatology, Department of Medicine, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Marie A Brunet
- https://ror.org/00kybxq39 Department of Paediatrics, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Sophie Roux
- https://ror.org/00kybxq39 Division of Rheumatology, Department of Medicine, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
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Meuten TK, Dean GA, Thamm DH. Review: The PI3K-AKT-mTOR signal transduction pathway in canine cancer. Vet Pathol 2024; 61:339-356. [PMID: 37905509 DOI: 10.1177/03009858231207021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Tumors in dogs and humans share many similar molecular and genetic features, incentivizing a better understanding of canine neoplasms not only for the purpose of treating companion animals, but also to facilitate research of spontaneously developing tumors with similar biologic behavior and treatment approaches in an immunologically competent animal model. Multiple tumor types of both species have similar dysregulation of signal transduction through phosphatidylinositol 3-kinase (PI3K), protein kinase B (PKB; AKT), and mechanistic target of rapamycin (mTOR), collectively known as the PI3K-AKT-mTOR pathway. This review aims to delineate the pertinent aspects of the PI3K-AKT-mTOR signaling pathway in health and in tumor development. It will then present a synopsis of current understanding of PI3K-AKT-mTOR signaling in important canine cancers and advancements in targeted inhibitors of this pathway.
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Nadile M, Sze NSK, Fajardo VA, Tsiani E. Inhibition of Prostate Cancer Cell Survival and Proliferation by Carnosic Acid Is Associated with Inhibition of Akt and Activation of AMPK Signaling. Nutrients 2024; 16:1257. [PMID: 38732504 PMCID: PMC11085396 DOI: 10.3390/nu16091257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/20/2024] [Accepted: 04/22/2024] [Indexed: 05/13/2024] Open
Abstract
Prostate cancer, accounting for 375,304 deaths in 2020, is the second most prevalent cancer in men worldwide. While many treatments exist for prostate cancer, novel therapeutic agents with higher efficacy are needed to target aggressive and hormone-resistant forms of prostate cancer, while sparing healthy cells. Plant-derived chemotherapy drugs such as docetaxel and paclitaxel have been established to treat cancers including prostate cancer. Carnosic acid (CA), a phenolic diterpene found in the herb rosemary (Rosmarinus officinalis) has been shown to have anticancer properties but its effects in prostate cancer and its mechanisms of action have not been examined. CA dose-dependently inhibited PC-3 and LNCaP prostate cancer cell survival and proliferation (IC50: 64, 21 µM, respectively). Furthermore, CA decreased phosphorylation/activation of Akt, mTOR, and p70 S6K. A notable increase in phosphorylation/activation of AMP-activated kinase (AMPK), acetyl-CoA carboxylase (ACC) and its upstream regulator sestrin-2 was seen with CA treatment. Our data indicate that CA inhibits AKT-mTORC1-p70S6K and activates Sestrin-2-AMPK signaling leading to a decrease in survival and proliferation. The use of inhibitors and small RNA interference (siRNA) approaches should be employed, in future studies, to elucidate the mechanisms involved in carnosic acid's inhibitory effects of prostate cancer.
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Affiliation(s)
- Matteo Nadile
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada; (M.N.); (N.S.K.S.); (V.A.F.)
| | - Newman Siu Kwan Sze
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada; (M.N.); (N.S.K.S.); (V.A.F.)
| | - Val A. Fajardo
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada; (M.N.); (N.S.K.S.); (V.A.F.)
| | - Evangelia Tsiani
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada; (M.N.); (N.S.K.S.); (V.A.F.)
- Centre for Bone and Muscle Health, Brock University, St. Catharines, ON L2S 3A1, Canada
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10
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Göttig L, Jummer S, Staehler L, Groitl P, Karimi M, Blanchette P, Kosulin K, Branton PE, Schreiner S. The human adenovirus PI3K-Akt activator E4orf1 is targeted by the tumor suppressor p53. J Virol 2024; 98:e0170123. [PMID: 38451084 PMCID: PMC11019960 DOI: 10.1128/jvi.01701-23] [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: 11/20/2023] [Accepted: 01/13/2024] [Indexed: 03/08/2024] Open
Abstract
Human adenoviruses (HAdV) are classified as DNA tumor viruses due to their potential to mediate oncogenic transformation in non-permissive mammalian cells and certain human stem cells. To achieve transformation, the viral early proteins of the E1 and E4 regions must block apoptosis and activate proliferation: the former predominantly through modulating the cellular tumor suppressor p53 and the latter by activating cellular pro-survival and pro-metabolism protein cascades, such as the phosphoinositide 3-kinase (PI3K-Akt) pathway, which is activated by HAdV E4orf1. Focusing on HAdV-C5, we show that E4orf1 is necessary and sufficient to stimulate Akt activation through phosphorylation in H1299 cells, which is not only hindered but repressed during HAdV-C5 infection with a loss of E4orf1 function in p53-positive A549 cells. Contrary to other research, E4orf1 localized not only in the common, cytoplasmic PI3K-Akt-containing compartment, but also in distinct nuclear aggregates. We identified a novel inhibitory mechanism, where p53 selectively targeted E4orf1 to destabilize it, also stalling E4orf1-dependent Akt phosphorylation. Co-IP and immunofluorescence studies showed that p53 and E4orf1 interact, and since p53 is bound by the HAdV-C5 E3 ubiquitin ligase complex, we also identified E4orf1 as a novel factor interacting with E1B-55K and E4orf6 during infection; overexpression of E4orf1 led to less-efficient E3 ubiquitin ligase-mediated proteasomal degradation of p53. We hypothesize that p53 specifically subverts the pro-survival function of E4orf1-mediated PI3K-Akt activation to protect the cell from metabolic hyper-activation or even transformation.IMPORTANCEHuman adenoviruses (HAdV) are nearly ubiquitous pathogens comprising numerous subtypes that infect various tissues and organs. Among many encoded proteins that facilitate viral replication and subversion of host cellular processes, the viral E4orf1 protein has emerged as an intriguing yet under-investigated player in the complex interplay between the virus and its host. Nonetheless, E4orf1 has gained attention as a metabolism activator and oncogenic agent, while recent research is showing that E4orf1 may play a more important role in modulating the cellular pathways such as phosphoinositide 3-kinase-Akt-mTOR. Our study reveals a novel and general impact of E4orf1 on host mechanisms, providing a novel basis for innovative antiviral strategies in future therapeutic settings. Ongoing investigations of the cellular pathways modulated by HAdV are of great interest, particularly since adenovirus-based vectors actually serve as vaccine or gene vectors. HAdV constitute an ideal model system to analyze the underlying molecular principles of virus-induced tumorigenesis.
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Affiliation(s)
- Lilian Göttig
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Simone Jummer
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Luisa Staehler
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Peter Groitl
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Maryam Karimi
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Paola Blanchette
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
- Goodman Cancer Research Center, McGill University, Montreal, Quebec, Canada
| | - Karin Kosulin
- Molecular Microbiology, Children’s Cancer Research Institute, Vienna, Austria
| | - Philip E. Branton
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
- Goodman Cancer Research Center, McGill University, Montreal, Quebec, Canada
| | - Sabrina Schreiner
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
- Cluster of Excellence RESIST (Resolving Infection Susceptibility; EXC 2155), Freiburg, Germany
- Institute of Virology, Medical Center—University of Freiburg, Freiburg, Germany
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11
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Hwang HJ, Kang D, Kim JR, Choi JH, Ryu JK, Herman AB, Ko YG, Park HJ, Gorospe M, Lee JS. FLRT2 prevents endothelial cell senescence and vascular aging by regulating the ITGB4/mTORC2/p53 signaling pathway. JCI Insight 2024; 9:e172678. [PMID: 38587072 PMCID: PMC11128196 DOI: 10.1172/jci.insight.172678] [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: 05/30/2023] [Accepted: 02/27/2024] [Indexed: 04/09/2024] Open
Abstract
The roles of fibronectin leucine-rich transmembrane protein 2 (FLRT2) in physiological and pathological processes are not well known. Here, we identify a potentially novel function of FLRT2 in preventing endothelial cell senescence and vascular aging. We found that FLRT2 expression was lower in cultured senescent endothelial cells as well as in aged rat and human vascular tissues. FLRT2 mediated endothelial cell senescence via the mTOR complex 2, AKT, and p53 signaling pathway in human endothelial cells. We uncovered that FLRT2 directly associated with integrin subunit beta 4 (ITGB4) and thereby promoted ITGB4 phosphorylation, while inhibition of ITGB4 substantially mitigated the induction of senescence triggered by FLRT2 depletion. Importantly, FLRT2 silencing in mice promoted vascular aging, and overexpression of FLRT2 rescued a premature vascular aging phenotype. Therefore, we propose that FLRT2 could be targeted therapeutically to prevent senescence-associated vascular aging.
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Affiliation(s)
- Hyun Jung Hwang
- Research Center for Controlling Intercellular Communication and
- Department of Molecular Medicine, College of Medicine, Inha University, Incheon, Korea
| | - Donghee Kang
- Research Center for Controlling Intercellular Communication and
- Department of Molecular Medicine, College of Medicine, Inha University, Incheon, Korea
- Program in Biomedical Science and Engineering, Inha University, Incheon, Korea
| | - Jae-Ryong Kim
- Department of Biochemistry and Molecular Biology and
| | - Joon Hyuk Choi
- Department of Pathology, College of Medicine, Yeungnam University, Daegu, Korea
| | - Ji-Kan Ryu
- Research Center for Controlling Intercellular Communication and
- Department of Urology, College of Medicine, Inha University, Incheon, Korea
| | - Allison B. Herman
- Laboratory of Genetics and Genomics, National Institute on Aging, Intramural Research Program, NIH, Baltimore, Maryland, USA
| | - Young-Gyu Ko
- Division of Life Sciences, Korea University, Seoul, Korea
| | - Heon Joo Park
- Research Center for Controlling Intercellular Communication and
- Program in Biomedical Science and Engineering, Inha University, Incheon, Korea
- Department of Microbiology, College of Medicine, Inha University, Incheon, Korea
| | - Myriam Gorospe
- Laboratory of Genetics and Genomics, National Institute on Aging, Intramural Research Program, NIH, Baltimore, Maryland, USA
| | - Jae-Seon Lee
- Research Center for Controlling Intercellular Communication and
- Department of Molecular Medicine, College of Medicine, Inha University, Incheon, Korea
- Program in Biomedical Science and Engineering, Inha University, Incheon, Korea
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12
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Galal MA, Al-Rimawi M, Hajeer A, Dahman H, Alouch S, Aljada A. Metformin: A Dual-Role Player in Cancer Treatment and Prevention. Int J Mol Sci 2024; 25:4083. [PMID: 38612893 PMCID: PMC11012626 DOI: 10.3390/ijms25074083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/30/2024] [Accepted: 04/02/2024] [Indexed: 04/14/2024] Open
Abstract
Cancer continues to pose a significant global health challenge, as evidenced by the increasing incidence rates and high mortality rates, despite the advancements made in chemotherapy. The emergence of chemoresistance further complicates the effectiveness of treatment. However, there is growing interest in the potential of metformin, a commonly prescribed drug for type 2 diabetes mellitus (T2DM), as an adjuvant chemotherapy agent in cancer treatment. Although the precise mechanism of action of metformin in cancer therapy is not fully understood, it has been found to have pleiotropic effects, including the modulation of metabolic pathways, reduction in inflammation, and the regulation of cellular proliferation. This comprehensive review examines the anticancer properties of metformin, drawing insights from various studies conducted in vitro and in vivo, as well as from clinical trials and observational research. This review discusses the mechanisms of action involving both insulin-dependent and independent pathways, shedding light on the potential of metformin as a therapeutic agent for different types of cancer. Despite promising findings, there are challenges that need to be addressed, such as conflicting outcomes in clinical trials, considerations regarding dosing, and the development of resistance. These challenges highlight the importance of further research to fully harness the therapeutic potential of metformin in cancer treatment. The aims of this review are to provide a contemporary understanding of the role of metformin in cancer therapy and identify areas for future exploration in the pursuit of effective anticancer strategies.
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Affiliation(s)
- Mariam Ahmed Galal
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
- Department of Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol BS8 1QU, UK
| | - Mohammed Al-Rimawi
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
| | | | - Huda Dahman
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
| | - Samhar Alouch
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
| | - Ahmad Aljada
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
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13
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Allard C, Miralpeix C, López-Gambero AJ, Cota D. mTORC1 in energy expenditure: consequences for obesity. Nat Rev Endocrinol 2024; 20:239-251. [PMID: 38225400 DOI: 10.1038/s41574-023-00934-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/29/2023] [Indexed: 01/17/2024]
Abstract
In eukaryotic cells, the mammalian target of rapamycin complex 1 (sometimes referred to as the mechanistic target of rapamycin complex 1; mTORC1) orchestrates cellular metabolism in response to environmental energy availability. As a result, at the organismal level, mTORC1 signalling regulates the intake, storage and use of energy by acting as a hub for the actions of nutrients and hormones, such as leptin and insulin, in different cell types. It is therefore unsurprising that deregulated mTORC1 signalling is associated with obesity. Strategies that increase energy expenditure offer therapeutic promise for the treatment of obesity. Here we review current evidence illustrating the critical role of mTORC1 signalling in the regulation of energy expenditure and adaptive thermogenesis through its various effects in neuronal circuits, adipose tissue and skeletal muscle. Understanding how mTORC1 signalling in one organ and cell type affects responses in other organs and cell types could be key to developing better, safer treatments targeting this pathway in obesity.
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Affiliation(s)
- Camille Allard
- University of Bordeaux, INSERM, Neurocentre Magendie, Bordeaux, France
| | | | | | - Daniela Cota
- University of Bordeaux, INSERM, Neurocentre Magendie, Bordeaux, France.
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14
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Liu YJ, Wang JY, Zhang XL, Jiang LL, Hu HY. Ataxin-2 sequesters Raptor into aggregates and impairs cellular mTORC1 signaling. FEBS J 2024; 291:1795-1812. [PMID: 38308810 DOI: 10.1111/febs.17081] [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: 08/02/2023] [Revised: 11/28/2023] [Accepted: 01/26/2024] [Indexed: 02/05/2024]
Abstract
Ataxin-2 (Atx2) is a polyglutamine (polyQ) protein, in which abnormal expansion of the polyQ tract can trigger protein aggregation and consequently cause spinocerebellar ataxia type 2 (SCA2), but the mechanism underlying how Atx2 aggregation leads to proteinopathy remains elusive. Here, we investigate the molecular mechanism and cellular consequences of Atx2 aggregation by molecular cell biology approaches. We have revealed that either normal or polyQ-expanded Atx2 can sequester Raptor, a component of mammalian target of rapamycin complex 1 (mTORC1), into aggregates based on their specific interaction. Further research indicates that the polyQ tract and the N-terminal region (residues 1-784) of Atx2 are responsible for the specific sequestration. Moreover, this sequestration leads to suppression of the mTORC1 activity as represented by down-regulation of phosphorylated P70S6K, which can be reversed by overexpression of Raptor. As mTORC1 is a key regulator of autophagy, Atx2 aggregation and sequestration also induces autophagy by upregulating LC3-II and reducing phosphorylated ULK1 levels. This study proposes that Atx2 sequesters Raptor into aggregates, thereby impairing cellular mTORC1 signaling and inducing autophagy, and will be beneficial for a better understanding of the pathogenesis of SCA2 and other polyQ diseases.
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Affiliation(s)
- Ya-Jun Liu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jian-Yang Wang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiang-Le Zhang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lei-Lei Jiang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
| | - Hong-Yu Hu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
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15
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Xia L, Nie T, Lu F, Huang L, Shi X, Ren D, Lu J, Li X, Xu T, Cui B, Wang Q, Gao G, Yang Q. Direct regulation of FNIP1 and FNIP2 by MEF2 sustains MTORC1 activation and tumor progression in pancreatic cancer. Autophagy 2024; 20:505-524. [PMID: 37772772 PMCID: PMC10936626 DOI: 10.1080/15548627.2023.2259735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 09/12/2023] [Indexed: 09/30/2023] Open
Abstract
MTOR (mechanistic target of rapamycin kinase) complex 1 (MTORC1) orchestrates diverse environmental signals to facilitate cell growth and is frequently activated in cancer. Translocation of MTORC1 from the cytosol to the lysosomal surface by the RRAG GTPases is the key step in MTORC1 activation. Here, we demonstrated that transcription factors MEF2A and MEF2D synergistically regulated MTORC1 activation via modulating its cyto-lysosome shutting. Mechanically, MEF2A and MEF2D controlled the transcription of FNIP1 and FNIP2, the components of the FLCN-FNIP1 or FNIP2 complex that acts as a RRAGC-RRAGD GTPase-activating element to promote the recruitment of MTORC1 to lysosome and its activation. Furthermore, we determined that the pro-oncogenic protein kinase SRC/c-Src directly phosphorylated MEF2D at three conserved tyrosine residues. The tyrosine phosphorylation enhanced MEF2D transcriptional activity and was indispensable for MTORC1 activation. Finally, both the protein and tyrosine phosphorylation levels of MEF2D are elevated in human pancreatic cancers, positively correlating with MTORC1 activity. Depletion of both MEF2A and MEF2D or expressing the unphosphorylatable MEF2D mutant suppressed tumor cell growth. Thus, our study revealed a transcriptional regulatory mechanism of MTORC1 that promoted cell anabolism and proliferation and uncovered its critical role in pancreatic cancer progression.Abbreviation: ACTB: actin beta; ChIP: chromatin immunoprecipitation; EGF: epidermal growth factor; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; FLCN: folliculin; FNIP1: folliculin interacting protein 1; FNIP2: folliculin interacting protein 2; GAP: GTPase activator protein; GEF: guanine nucleotide exchange factors; GTPase: guanosine triphosphatase; LAMP2: lysosomal associated membrane protein 2; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MEF2: myocyte enhancer factor 2; MEF2A: myocyte enhancer factor 2A; MEF2D: myocyte enhancer factor 2D; MEF2D-3YF: Y131F, Y333F, Y337F mutant; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; NR4A1: nuclear receptor subfamily 4 group A member 1; RPTOR: regulatory associated protein of MTOR complex 1; RHEB: Ras homolog, mTORC1 binding; RPS6KB1: ribosomal protein S6 kinase B1; RRAG: Ras related GTP binding; RT-qPCR: real time-quantitative PCR; SRC: SRC proto-oncogene, non-receptor tyrosine kinase; TMEM192: transmembrane protein 192; WT: wild-type.
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Affiliation(s)
- Li Xia
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Tiejian Nie
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Fangfang Lu
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Lu Huang
- Department of Anesthesiology, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Xiaolong Shi
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Dongni Ren
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Jianjun Lu
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Xiaobin Li
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Tuo Xu
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Bozhou Cui
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Qing Wang
- Department of General Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Guodong Gao
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Qian Yang
- Department of Experimental Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China
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16
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Göttig L, Schreiner S. E4orf1: The triple agent of adenovirus - Unraveling its roles in oncogenesis, infectious obesity and immune responses in virus replication and vector therapy. Tumour Virus Res 2024; 17:200277. [PMID: 38428735 PMCID: PMC10937242 DOI: 10.1016/j.tvr.2024.200277] [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: 01/22/2024] [Revised: 02/20/2024] [Accepted: 02/20/2024] [Indexed: 03/03/2024] Open
Abstract
Human Adenoviruses (HAdV) are nearly ubiquitous pathogens comprising numerous sub-types that infect various tissues and organs. Among many encoded proteins that facilitate viral replication and subversion of host cellular processes, the viral E4orf1 protein has emerged as an intriguing yet under-investigated player in the complex interplay between the virus and its host. E4orf1 has gained attention as a metabolism activator and oncogenic agent, while recent research is showing that E4orf1 may play a more important role in modulating cellular pathways such as PI3K-Akt-mTOR, Ras, the immune response and further HAdV replication stages than previously anticipated. In this review, we aim to explore the structure, molecular mechanisms, and biological functions of E4orf1, shedding light on its potentially multifaceted roles during HAdV infection, including metabolic diseases and oncogenesis. Furthermore, we discuss the role of functional E4orf1 in biotechnological applications such as Adenovirus (AdV) vaccine vectors and oncolytic AdV. By dissecting the intricate relationships between HAdV types and E4orf1 proteins, this review provides valuable insights into viral pathogenesis and points to promising areas of future research.
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Affiliation(s)
- Lilian Göttig
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
| | - Sabrina Schreiner
- Institute of Virology, School of Medicine, Technical University of Munich, Germany; Institute of Virology, Hannover Medical School, Hannover, Germany; Cluster of Excellence RESIST (Resolving Infection Susceptibility; EXC 2155), Hannover, Germany; Institute of Virology, Medical Center - University of Freiburg, Freiburg, Germany.
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17
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Gargalionis AN, Papavassiliou KA, Papavassiliou AG. mTOR Signaling: Recent Progress. Int J Mol Sci 2024; 25:2587. [PMID: 38473834 DOI: 10.3390/ijms25052587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 02/21/2024] [Indexed: 03/14/2024] Open
Abstract
In the intricate landscape of human biology, the mechanistic target of rapamycin (mTOR) emerges as a key regulator, orchestrating a vast array of processes in health and disease [...].
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Affiliation(s)
- Antonios N Gargalionis
- Department of Biopathology, 'Eginition' Hospital, Medical School, National and Kapodistrian University of Athens, 11528 Athens, Greece
| | - Kostas A Papavassiliou
- 'Sotiria' Hospital, Medical School, First University Department of Respiratory Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Athanasios G Papavassiliou
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
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18
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Ren Q, Nie X, Ma X, Han Z, Li Y, Yang X, Ji L, Su R, Ge J, Huang X. The crosstalk between Toll and AMPK signaling pathways mediates growth inhibition of Eriocheir sinensis under deltamethrin stress. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2024; 267:106832. [PMID: 38215609 DOI: 10.1016/j.aquatox.2024.106832] [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: 09/15/2023] [Revised: 12/09/2023] [Accepted: 01/07/2024] [Indexed: 01/14/2024]
Abstract
Hepatopancreatic necrosis disease (HPND) broke out in 2015 in the Eriocheir sinensis aquaculture region of Xinghua, Jiangsu Province; however, the specific cause of HPND remains unclear. A correlation was found between HPND outbreak and the use of deltamethrin by farmers. In this study, E. sinensis specimens developed the clinical symptoms of HPND after 93 days of deltamethrin stress. The growth of E. sinensis with HPND was inhibited. Adenosine monophosphate-activated protein kinase (AMPK) is a central regulator of energy homeostasis, and its expression was up-regulated in the intestine of E. sinensis with HPND. Growth inhibitory genes (EsCabut, Es4E-BP, and EsCG6770) were also up-regulated in the intestine of E. sinensis with HPND. The expression levels of EsCabut, Es4E-BP, and EsCG6770 decreased after EsAMPK knockdown. Therefore, AMPK mediated the growth inhibition of E. sinensis with HPND. Further analysis indicated the presence of a crosstalk between the Toll and AMPK signaling pathways in E. sinensis with HPND. Multiple genes in the Toll signaling pathway were upregulated in E. sinensis under 93 days of deltamethrin stress. EsAMPK and its regulated growth inhibition genes were down-regulated after the knockdown of genes in the Toll pathway. In summary, the crosstalk between the Toll and AMPK signaling pathways mediates the growth inhibition of E. sinensis under deltamethrin stress.
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Affiliation(s)
- Qian Ren
- School of Marine Sciences, Nanjing University of information Science & Technology, Nanjing, Jiangsu Province, 210044, PR China.
| | - Ximei Nie
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province, 210023, PR China
| | - Xingkong Ma
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, PR China
| | - Zhengxiao Han
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province, 210023, PR China
| | - Yanfang Li
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province, 210023, PR China
| | - Xintong Yang
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province, 210023, PR China
| | - Lei Ji
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province, 210023, PR China
| | - Rongqian Su
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province, 210023, PR China
| | - Jiachun Ge
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, PR China.
| | - Xin Huang
- Jiangsu Province Engineering Research Center for Aquatic Animals Breeding and Green Efficient Aquacultural Technology, College of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu Province, 210023, PR China.
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19
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Abudu YP, Kournoutis A, Brenne HB, Lamark T, Johansen T. MORG1 limits mTORC1 signaling by inhibiting Rag GTPases. Mol Cell 2024; 84:552-569.e11. [PMID: 38103557 DOI: 10.1016/j.molcel.2023.11.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 10/02/2023] [Accepted: 11/17/2023] [Indexed: 12/19/2023]
Abstract
Autophagy, an important quality control and recycling process vital for cellular homeostasis, is tightly regulated. The mTORC1 signaling pathway regulates autophagy under conditions of nutrient availability and scarcity. However, how mTORC1 activity is fine-tuned during nutrient availability to allow basal autophagy is unclear. Here, we report that the WD-domain repeat protein MORG1 facilitates basal constitutive autophagy by inhibiting mTORC1 signaling through Rag GTPases. Mechanistically, MORG1 interacts with active Rag GTPase complex inhibiting the Rag GTPase-mediated recruitment of mTORC1 to the lysosome. MORG1 depletion in HeLa cells increases mTORC1 activity and decreases autophagy. The autophagy receptor p62/SQSTM1 binds to MORG1, but MORG1 is not an autophagy substrate. However, p62/SQSTM1 binding to MORG1 upon re-addition of amino acids following amino acid's depletion precludes MORG1 from inhibiting the Rag GTPases, allowing mTORC1 activation. MORG1 depletion increases cell proliferation and migration. Low expression of MORG1 correlates with poor survival in several important cancers.
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Affiliation(s)
- Yakubu Princely Abudu
- Autophagy Research Group, Department of Medical Biology, University of Tromsø-The Arctic University of Norway, Tromsø, Norway; Nanoscopy Group, Department of Physics and Technology, University of Tromsø-The Arctic University of Norway, Tromsø, Norway.
| | - Athanasios Kournoutis
- Autophagy Research Group, Department of Medical Biology, University of Tromsø-The Arctic University of Norway, Tromsø, Norway
| | - Hanne Britt Brenne
- Autophagy Research Group, Department of Medical Biology, University of Tromsø-The Arctic University of Norway, Tromsø, Norway
| | - Trond Lamark
- Autophagy Research Group, Department of Medical Biology, University of Tromsø-The Arctic University of Norway, Tromsø, Norway
| | - Terje Johansen
- Autophagy Research Group, Department of Medical Biology, University of Tromsø-The Arctic University of Norway, Tromsø, Norway.
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20
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Shin HC, Kim J, Park SR, Choi BH. mTOR Plays an Important Role in the Stemness of Human Fetal Cartilage Progenitor Cells (hFCPCs). Tissue Eng Regen Med 2024; 21:309-318. [PMID: 37812329 PMCID: PMC10825109 DOI: 10.1007/s13770-023-00598-x] [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: 08/18/2023] [Revised: 08/18/2023] [Accepted: 09/07/2023] [Indexed: 10/10/2023] Open
Abstract
BACKGROUND Mammalian target of rapamycin (mTOR) is known to regulate self-renewal ability and potency of embryonic stem cells (ESCs) and adult stem cells in opposite manners. However, its effects vary even among adult stem cells and are not reported in fetal stem/progenitor cells. This study investigated the role of mTOR in the function of human fetal cartilage-derived progenitor cells (hFCPCs). METHODS mTOR activity in hFCPCs was first examined via the level of phosphor-mTOR until passage 19, together with doubling time of cells and senescence-associated b-galactosidase (SA-bGal). Then, the effect of 100 nM rapamycin, the inhibitor of mTOR, was investigated on self-renewal ability, proliferation rate and osteogenic/adipogenic potential of hFCPCs in vitro. Expression of stemness genes (Oct-4, Sox2 and Nanog) and cell cycle regulators (CDK4 and Cyclin D1) was measured at mRNA or protein levels. RESULTS mTOR activity was maintained constantly at high levels in hFCPCs until passage 19, while their proliferation rate was decreasing from 48 h at passage 13 to 70 h at passage 9 and senescent cells were observed at passage 18 (8.3 ± 1.2%) and 19 (15.6 ± 1.9%). Inhibition of mTOR in hFCPCs impaired their colony forming frequency (CFU-F) by 4 folds, while showing no change in their doubling time and expression of CDK4 and Cyclin D1. Upon mTOR inhibition, Oct4 expression decreased by 2 folds and 4 folds at the mRNA and protein levels, respectively, while that of Sox2 and Nanog did not change significantly. Finally, mTOR inhibition reduced osteogenic and adipogenic differentiation of hFCPCs in vitro. CONCLUSION This study has shown that mTOR plays an important role in the self-renewal ability of hFCPCS but not in their proliferation, The effect of mTOR appears to be associated with Oct-4 expression and important in the osteogenic and adipogenic differentiation ability of hFCPCs.
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Affiliation(s)
- Him-Cha Shin
- Department of Physiology and Biophysics, Inha University College of Medicine, 100 Inha-ro, Michuhol-gu, Incheon, 22212, South Korea
| | - Jiyoung Kim
- Department of Biomedical Sciences, Inha University College of Medicine, 100 Inha-ro, Michuhol-gu, Incheon, 22212, South Korea
| | - So Ra Park
- Department of Physiology and Biophysics, Inha University College of Medicine, 100 Inha-ro, Michuhol-gu, Incheon, 22212, South Korea
| | - Byung Hyune Choi
- Department of Biomedical Sciences, Inha University College of Medicine, 100 Inha-ro, Michuhol-gu, Incheon, 22212, South Korea.
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21
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Ragupathi A, Kim C, Jacinto E. The mTORC2 signaling network: targets and cross-talks. Biochem J 2024; 481:45-91. [PMID: 38270460 PMCID: PMC10903481 DOI: 10.1042/bcj20220325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/29/2023] [Accepted: 12/18/2023] [Indexed: 01/26/2024]
Abstract
The mechanistic target of rapamycin, mTOR, controls cell metabolism in response to growth signals and stress stimuli. The cellular functions of mTOR are mediated by two distinct protein complexes, mTOR complex 1 (mTORC1) and mTORC2. Rapamycin and its analogs are currently used in the clinic to treat a variety of diseases and have been instrumental in delineating the functions of its direct target, mTORC1. Despite the lack of a specific mTORC2 inhibitor, genetic studies that disrupt mTORC2 expression unravel the functions of this more elusive mTOR complex. Like mTORC1 which responds to growth signals, mTORC2 is also activated by anabolic signals but is additionally triggered by stress. mTORC2 mediates signals from growth factor receptors and G-protein coupled receptors. How stress conditions such as nutrient limitation modulate mTORC2 activation to allow metabolic reprogramming and ensure cell survival remains poorly understood. A variety of downstream effectors of mTORC2 have been identified but the most well-characterized mTORC2 substrates include Akt, PKC, and SGK, which are members of the AGC protein kinase family. Here, we review how mTORC2 is regulated by cellular stimuli including how compartmentalization and modulation of complex components affect mTORC2 signaling. We elaborate on how phosphorylation of its substrates, particularly the AGC kinases, mediates its diverse functions in growth, proliferation, survival, and differentiation. We discuss other signaling and metabolic components that cross-talk with mTORC2 and the cellular output of these signals. Lastly, we consider how to more effectively target the mTORC2 pathway to treat diseases that have deregulated mTOR signaling.
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Affiliation(s)
- Aparna Ragupathi
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, U.S.A
| | - Christian Kim
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, U.S.A
| | - Estela Jacinto
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, U.S.A
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22
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Liu Y, Zhang M, Jang H, Nussinov R. The allosteric mechanism of mTOR activation can inform bitopic inhibitor optimization. Chem Sci 2024; 15:1003-1017. [PMID: 38239681 PMCID: PMC10793652 DOI: 10.1039/d3sc04690g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 12/06/2023] [Indexed: 01/22/2024] Open
Abstract
mTOR serine/threonine kinase is a cornerstone in the PI3K/AKT/mTOR pathway. Yet, the detailed mechanism of activation of its catalytic core is still unresolved, likely due to mTOR complexes' complexity. Its dysregulation was implicated in cancer and neurodevelopmental disorders. Using extensive molecular dynamics (MD) simulations and compiled published experimental data, we determine exactly how mTOR's inherent motifs can control the conformational changes in the kinase domain, thus kinase activity. We also chronicle the critical regulation by the unstructured negative regulator domain (NRD). When positioned inside the catalytic cleft (NRD IN state), mTOR tends to adopt a deep and closed catalytic cleft. This is primarily due to the direct interaction with the FKBP-rapamycin binding (FRB) domain which restricts it, preventing substrate access. Conversely, when outside the catalytic cleft (NRD OUT state), mTOR favors an open conformation, exposing the substrate-binding site on the FRB domain. We further show how an oncogenic mutation (L2427R) promotes shifting the mTOR ensemble toward the catalysis-favored state. Collectively, we extend mTOR's "active-site restriction" mechanism and clarify mutation action. In particular, our mechanism suggests that RMC-5552 (RMC-6272) bitopic inhibitors may benefit from adjustment of the (PEG8) linker length when targeting certain mTOR variants. In the cryo-EM mTOR/RMC-5552 structure, the distance between the allosteric and orthosteric inhibitors is ∼22.7 Å. With a closed catalytic cleft, this linker bridges the sites. However, in our activation mechanism, in the open cleft it expands to ∼24.7 Å, offering what we believe to be the first direct example of how discovering an activation mechanism can potentially increase the affinity of inhibitors targeting mutants.
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Affiliation(s)
- Yonglan Liu
- Cancer Innovation Laboratory, National Cancer Institute Frederick MD 21702 USA
| | - Mingzhen Zhang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research Frederick MD 21702 USA +1-301-846-5579
| | - Hyunbum Jang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research Frederick MD 21702 USA +1-301-846-5579
| | - Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research Frederick MD 21702 USA +1-301-846-5579
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University Tel Aviv 69978 Israel
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23
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Karalis V, Wood D, Teaney NA, Sahin M. The role of TSC1 and TSC2 proteins in neuronal axons. Mol Psychiatry 2024:10.1038/s41380-023-02402-7. [PMID: 38212374 DOI: 10.1038/s41380-023-02402-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/13/2024]
Abstract
Tuberous Sclerosis Complex 1 and 2 proteins, TSC1 and TSC2 respectively, participate in a multiprotein complex with a crucial role for the proper development and function of the nervous system. This complex primarily acts as an inhibitor of the mechanistic target of rapamycin (mTOR) kinase, and mutations in either TSC1 or TSC2 cause a neurodevelopmental disorder called Tuberous Sclerosis Complex (TSC). Neurological manifestations of TSC include brain lesions, epilepsy, autism, and intellectual disability. On the cellular level, the TSC/mTOR signaling axis regulates multiple anabolic and catabolic processes, but it is not clear how these processes contribute to specific neurologic phenotypes. Hence, several studies have aimed to elucidate the role of this signaling pathway in neurons. Of particular interest are axons, as axonal defects are associated with severe neurocognitive impairments. Here, we review findings regarding the role of the TSC1/2 protein complex in axons. Specifically, we will discuss how TSC1/2 canonical and non-canonical functions contribute to the formation and integrity of axonal structure and function.
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Affiliation(s)
- Vasiliki Karalis
- Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Delaney Wood
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, 02115, USA
- Human Neuron Core, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Nicole A Teaney
- Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Mustafa Sahin
- Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, 02115, USA.
- Human Neuron Core, Boston Children's Hospital, Boston, MA, 02115, USA.
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24
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Mangione MC, Wen J, Cao DJ. Mechanistic target of rapamycin in regulating macrophage function in inflammatory cardiovascular diseases. J Mol Cell Cardiol 2024; 186:111-124. [PMID: 38039845 PMCID: PMC10843805 DOI: 10.1016/j.yjmcc.2023.10.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 10/14/2023] [Accepted: 10/18/2023] [Indexed: 12/03/2023]
Abstract
The mechanistic target of rapamycin (mTOR) is evolutionarily conserved from yeast to humans and is one of the most fundamental pathways of living organisms. Since its discovery three decades ago, mTOR has been recognized as the center of nutrient sensing and growth, homeostasis, metabolism, life span, and aging. The role of dysregulated mTOR in common diseases, especially cancer, has been extensively studied and reported. Emerging evidence supports that mTOR critically regulates innate immune responses that govern the pathogenesis of various cardiovascular diseases. This review discusses the regulatory role of mTOR in macrophage functions in acute inflammation triggered by ischemia and in atherosclerotic cardiovascular disease (ASCVD) and heart failure with preserved ejection fraction (HFpEF), in which chronic inflammation plays critical roles. Specifically, we discuss the role of mTOR in trained immunity, immune senescence, and clonal hematopoiesis. In addition, this review includes a discussion on the architecture of mTOR, the function of its regulatory complexes, and the dual-arm signals required for mTOR activation to reflect the current knowledge state. We emphasize future research directions necessary to understand better the powerful pathway to take advantage of the mTOR inhibitors for innovative applications in patients with cardiovascular diseases associated with aging and inflammation.
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Affiliation(s)
- MariaSanta C Mangione
- Department of Internal Medicine, Cardiology Division, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jinhua Wen
- Department of Internal Medicine, Cardiology Division, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Dian J Cao
- Department of Internal Medicine, Cardiology Division, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; VA North Texas Health Care System, Dallas TX 75216, USA.
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25
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Fusse EJ, Scarante FF, Vicente MA, Marrubia MM, Turcato F, Scomparin DS, Ribeiro MA, Figueiredo MJ, Brigante TAV, Guimarães FS, Campos AC. Anxiogenic doses of rapamycin prevent URB597-induced anti-stress effects in socially defeated mice. Neurosci Lett 2024; 818:137519. [PMID: 37852528 DOI: 10.1016/j.neulet.2023.137519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 10/06/2023] [Accepted: 10/11/2023] [Indexed: 10/20/2023]
Abstract
Repeated exposure to psychosocial stress modulates the endocannabinoid system, particularly anandamide (AEA) signaling in brain regions associated with emotional distress. The mTOR protein regulates various neuroplastic processes in the brain disrupted by stress, including adult hippocampal neurogenesis. This kinase has been implicated in multiple effects of cannabinoid drugs and the anti-stress behavioral effects of psychoactive drugs. Therefore, our hypothesis is that enhancing AEA signaling via pharmacological inhibition of the fatty acid amide hydrolase (FAAH) enzyme induces an anti-stress behavioral effect through an mTOR-dependent mechanism. To test this hypothesis, male C57Bl6 mice were exposed to social defeat stress (SDS) for 7 days and received daily treatment with either vehicle or different doses of the FAAH inhibitor, URB597 (0.1; 0.3; 1 mg/Kg), alone or combined with rapamycin. The results suggested that URB597 induced an inverted U-shaped dose-response curve in mice subjected to SDS (with the intermediate dose of 0.3 mg/kg being anxiolytic, and the higher tested dose of 1 mg/Kg being anxiogenic). In a second independent experiment, rapamycin treatment induced an anxiogenic-like response in control mice. However, in the presence of rapamycin, the anxiolytic dose of URB597 treatment failed to reduce stress-induced anxiety behaviors in mice. SDS exposure altered the hippocampal expression of the mTOR scaffold protein Raptor. Furthermore, the anxiogenic dose of URB597 decreased the absolute number of migrating doublecortin (DCX)-positive cells in the dentate gyrus, suggesting an anti-anxiety effect independent of newly generated/immature neurons. Therefore, our results indicate that in mice exposed to repeated psychosocial stress, URB597 fails to counteract the anxiogenic-like response induced by the pharmacological dampening of mTOR signaling.
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Affiliation(s)
- Eduardo J Fusse
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Franciele F Scarante
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Maria A Vicente
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Mariana M Marrubia
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Flávia Turcato
- Department of Neurological Surgery, Case Western Reserve University, Cleveland, USA
| | - Davi S Scomparin
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Melissa A Ribeiro
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Maria J Figueiredo
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Tamires A V Brigante
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Francisco S Guimarães
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Alline C Campos
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil.
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26
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Powell JT, Kayesh R, Ballesteros-Perez A, Alam K, Niyonshuti P, Soderblom EJ, Ding K, Xu C, Yue W. Assessing Trans-Inhibition of OATP1B1 and OATP1B3 by Calcineurin and/or PPIase Inhibitors and Global Identification of OATP1B1/3-Associated Proteins. Pharmaceutics 2023; 16:63. [PMID: 38258074 PMCID: PMC10818623 DOI: 10.3390/pharmaceutics16010063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 12/11/2023] [Accepted: 12/26/2023] [Indexed: 01/24/2024] Open
Abstract
Organic anion transporting polypeptide (OATP) 1B1 and OATP1B3 are key determinants of drug-drug interactions (DDIs). Various drugs including the calcineurin inhibitor (CNI) cyclosporine A (CsA) exert preincubation-induced trans-inhibitory effects upon OATP1B1 and/or OATP1B3 (abbreviated as OATP1B1/3) by unknown mechanism(s). OATP1B1/3 are phosphoproteins; calcineurin, which dephosphorylates and regulates numerous phosphoproteins, has not previously been investigated in the context of preincubation-induced trans-inhibition of OATP1B1/3. Herein, we compare the trans-inhibitory effects exerted on OATP1B1 and OATP1B3 by CsA, the non-analogous CNI tacrolimus, and the non-CNI CsA analogue SCY-635 in transporter-overexpressing human embryonic kidney (HEK) 293 stable cell lines. Preincubation (10-60 min) with tacrolimus (1-10 µM) rapidly and significantly reduces OATP1B1- and OATP1B3-mediated transport up to 0.18 ± 0.03- and 0.20 ± 0.02-fold compared to the control, respectively. Both CsA and SCY-635 can trans-inhibit OATP1B1, with the inhibitory effects progressively increasing over a 60 min preincubation time. At each equivalent preincubation time, CsA has greater trans-inhibitory effects toward OATP1B1 than SCY-635. Preincubation with SCY-635 for 60 min yielded IC50 of 2.2 ± 1.4 µM against OATP1B1, which is ~18 fold greater than that of CsA (0.12 ± 0.04 µM). Furthermore, a proteomics-based screening for protein interactors was used to examine possible proteins and processes contributing to OATP1B1/3 regulation and preincubation-induced inhibition by CNIs and other drugs. A total of 861 and 357 proteins were identified as specifically associated with OATP1B1 and OATP1B3, respectively, including various protein kinases, ubiquitin-related enzymes, the tacrolimus (FK506)-binding proteins FKBP5 and FKBP8, and several known regulatory targets of calcineurin. The current study reports several novel findings that expand our understanding of impaired OATP1B1/3 function; these include preincubation-induced trans-inhibition of OATP1B1/3 by the CNI tacrolimus, greater preincubation-induced inhibition by CsA compared to its non-CNI analogue SCY-635, and association of OATP1B1/3 with various proteins relevant to established and candidate OATP1B1/3 regulatory processes.
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Affiliation(s)
- John T. Powell
- Department of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73117, USA; (J.T.P.)
| | - Ruhul Kayesh
- Department of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73117, USA; (J.T.P.)
| | - Alexandra Ballesteros-Perez
- Department of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73117, USA; (J.T.P.)
| | - Khondoker Alam
- Department of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73117, USA; (J.T.P.)
| | - Pascaline Niyonshuti
- Department of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73117, USA; (J.T.P.)
| | - Erik J. Soderblom
- Proteomics and Metabolomics Core Facility, Duke University School of Medicine, Durham, NC 27708, USA
| | - Kai Ding
- Department of Biostatistics & Epidemiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (K.D.); (C.X.)
| | - Chao Xu
- Department of Biostatistics & Epidemiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (K.D.); (C.X.)
| | - Wei Yue
- Department of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73117, USA; (J.T.P.)
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27
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Tsutsumi K, Nohara A, Tanaka T, Murano M, Miyagaki Y, Ohta Y. FilGAP regulates tumor growth in Glioma through the regulation of mTORC1 and mTORC2. Sci Rep 2023; 13:20956. [PMID: 38065968 PMCID: PMC10709582 DOI: 10.1038/s41598-023-47892-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 11/20/2023] [Indexed: 12/18/2023] Open
Abstract
The mechanistic target of rapamycin (mTOR) is a serine/threonine protein kinase that forms the two different protein complexes, known as mTORC1 and mTORC2. mTOR signaling is activated in a variety of tumors, including glioma that is one of the malignant brain tumors. FilGAP (ARHGAP24) is a negative regulator of Rac, a member of Rho family small GTPases. In this study, we found that FilGAP interacts with mTORC1/2 and is involved in tumor formation in glioma. FilGAP interacted with mTORC1 via Raptor and with mTORC2 via Rictor and Sin1. Depletion of FilGAP in KINGS-1 glioma cells decreased phosphorylation of S6K and AKT. Furthermore, overexpression of FilGAP increased phosphorylation of S6K and AKT, suggesting that FilGAP activates mTORC1/2. U-87MG, glioblastoma cells, showed higher mTOR activity than KINGS-1, and phosphorylation of S6K and AKT was not affected by suppression of FilGAP expression. However, in the presence of PI3K inhibitors, phosphorylation of S6K and AKT was also decreased in U-87MG by depletion of FilGAP, suggesting that FilGAP may also regulate mTORC2 in U-87MG. Finally, we showed that depletion of FilGAP in KINGS-1 and U-87MG cells significantly reduced spheroid growth. These results suggest that FilGAP may contribute to tumor growth in glioma by regulating mTORC1/2 activities.
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Affiliation(s)
- Koji Tsutsumi
- Division of Cell Biology, Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Sagamihara, Minami-Ku, Kanagawa, 252-0373, Japan.
| | - Ayumi Nohara
- Division of Cell Biology, Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Sagamihara, Minami-Ku, Kanagawa, 252-0373, Japan
| | - Taiki Tanaka
- Division of Cell Biology, Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Sagamihara, Minami-Ku, Kanagawa, 252-0373, Japan
| | - Moe Murano
- Division of Cell Biology, Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Sagamihara, Minami-Ku, Kanagawa, 252-0373, Japan
| | - Yurina Miyagaki
- Division of Cell Biology, Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Sagamihara, Minami-Ku, Kanagawa, 252-0373, Japan
| | - Yasutaka Ohta
- Division of Cell Biology, Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Sagamihara, Minami-Ku, Kanagawa, 252-0373, Japan.
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28
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Ge MK, Zhang C, Zhang N, He P, Cai HY, Li S, Wu S, Chu XL, Zhang YX, Ma HM, Xia L, Yang S, Yu JX, Yao SY, Zhou XL, Su B, Chen GQ, Shen SM. The tRNA-GCN2-FBXO22-axis-mediated mTOR ubiquitination senses amino acid insufficiency. Cell Metab 2023; 35:2216-2230.e8. [PMID: 37979583 DOI: 10.1016/j.cmet.2023.10.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 07/26/2023] [Accepted: 10/26/2023] [Indexed: 11/20/2023]
Abstract
Mammalian target of rapamycin complex 1 (mTORC1) monitors cellular amino acid changes for function, but the molecular mediators of this process remain to be fully defined. Here, we report that depletion of cellular amino acids, either alone or in combination, leads to the ubiquitination of mTOR, which inhibits mTORC1 kinase activity by preventing substrate recruitment. Mechanistically, amino acid depletion causes accumulation of uncharged tRNAs, thereby stimulating GCN2 to phosphorylate FBXO22, which in turn accrues in the cytoplasm and ubiquitinates mTOR at Lys2066 in a K27-linked manner. Accordingly, mutation of mTOR Lys2066 abolished mTOR ubiquitination in response to amino acid depletion, rendering mTOR insensitive to amino acid starvation both in vitro and in vivo. Collectively, these data reveal a novel mechanism of amino acid sensing by mTORC1 via a previously unknown GCN2-FBXO22-mTOR pathway that is uniquely controlled by uncharged tRNAs.
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Affiliation(s)
- Meng-Kai Ge
- Institute of Aging & Tissue Regeneration, State Key Laboratory of Systems Medicine for Cancer and Stress and Cancer Research Unit of Chinese Academy of Medical Sciences (No. 2019RU043), Ren-Ji Hospital, Shanghai Jiao Tong University School of Medicine (SJTU-SM), Shanghai 200127, China; Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China
| | - Cheng Zhang
- Institute of Aging & Tissue Regeneration, State Key Laboratory of Systems Medicine for Cancer and Stress and Cancer Research Unit of Chinese Academy of Medical Sciences (No. 2019RU043), Ren-Ji Hospital, Shanghai Jiao Tong University School of Medicine (SJTU-SM), Shanghai 200127, China
| | - Na Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China
| | - Ping He
- Institute of Aging & Tissue Regeneration, State Key Laboratory of Systems Medicine for Cancer and Stress and Cancer Research Unit of Chinese Academy of Medical Sciences (No. 2019RU043), Ren-Ji Hospital, Shanghai Jiao Tong University School of Medicine (SJTU-SM), Shanghai 200127, China
| | - Hai-Yan Cai
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Song Li
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, SJTU-SM, Shanghai 200025, China
| | - Shuai Wu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China
| | - Xi-Li Chu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China
| | - Yu-Xue Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China
| | - Hong-Ming Ma
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China
| | - Li Xia
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China
| | - Shuo Yang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China
| | - Jian-Xiu Yu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China
| | - Shi-Ying Yao
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xiao-Long Zhou
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Bing Su
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, SJTU-SM, Shanghai 200025, China.
| | - Guo-Qiang Chen
- Institute of Aging & Tissue Regeneration, State Key Laboratory of Systems Medicine for Cancer and Stress and Cancer Research Unit of Chinese Academy of Medical Sciences (No. 2019RU043), Ren-Ji Hospital, Shanghai Jiao Tong University School of Medicine (SJTU-SM), Shanghai 200127, China; Hainan Academy of Medical Sciences, Hainan Medical University, Hainan 571199, China.
| | - Shao-Ming Shen
- Institute of Aging & Tissue Regeneration, State Key Laboratory of Systems Medicine for Cancer and Stress and Cancer Research Unit of Chinese Academy of Medical Sciences (No. 2019RU043), Ren-Ji Hospital, Shanghai Jiao Tong University School of Medicine (SJTU-SM), Shanghai 200127, China; Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China.
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Goul C, Peruzzo R, Zoncu R. The molecular basis of nutrient sensing and signalling by mTORC1 in metabolism regulation and disease. Nat Rev Mol Cell Biol 2023; 24:857-875. [PMID: 37612414 DOI: 10.1038/s41580-023-00641-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/06/2023] [Indexed: 08/25/2023]
Abstract
The Ser/Thr kinase mechanistic target of rapamycin (mTOR) is a central regulator of cellular metabolism. As part of mTOR complex 1 (mTORC1), mTOR integrates signals such as the levels of nutrients, growth factors, energy sources and oxygen, and triggers responses that either boost anabolism or suppress catabolism. mTORC1 signalling has wide-ranging consequences for the growth and homeostasis of key tissues and organs, and its dysregulated activity promotes cancer, type 2 diabetes, neurodegeneration and other age-related disorders. How mTORC1 integrates numerous upstream cues and translates them into specific downstream responses is an outstanding question with major implications for our understanding of physiology and disease mechanisms. In this Review, we discuss recent structural and functional insights into the molecular architecture of mTORC1 and its lysosomal partners, which have greatly increased our mechanistic understanding of nutrient-dependent mTORC1 regulation. We also discuss the emerging involvement of aberrant nutrient-mTORC1 signalling in multiple diseases.
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Affiliation(s)
- Claire Goul
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Roberta Peruzzo
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Roberto Zoncu
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
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30
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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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31
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Yu FY, Zheng K, Wu YF, Gao SW, Weng QY, Zhu C, Wu YP, Li M, Qin ZN, Lou JF, Chen ZH, Ying SM, Shen HH, Li W. Rapamycin Exacerbates Staphylococcus aureus Pneumonia by Inhibiting mTOR-RPS6 in Macrophages. J Inflamm Res 2023; 16:5715-5728. [PMID: 38053607 PMCID: PMC10695130 DOI: 10.2147/jir.s434483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 11/17/2023] [Indexed: 12/07/2023] Open
Abstract
Purpose This study aimed to explore the effect of Rapamycin (Rapa) in Staphylococcus aureus (S. aureus) pneumonia and clarify its possible mechanism. Methods We investigated the effects of Rapa on S. aureus pneumonia in mouse models and in macrophages cultured in vitro. Two possible mechanisms were investigated: the mTOR-RPS6 pathway phosphorylation and phagocytosis. Furthermore, for the mechanism verification in vivo, mice with specific Mtor knockout in myeloid cells were constructed for pneumonia models. Results Rapa exacerbated S. aureus pneumonia in mouse models, promoting chemokines secretion and inflammatory cells infiltration in lung. In vitro, Rapa upregulated the secretion of chemokines and cytokines in macrophages induced by S. aureus. Mechanistically, the mTOR-ribosomal protein S6 (RPS6) pathway in macrophages was phosphorylated in response to S. aureus infection, and the inhibition of RPS6 phosphorylation upregulated the inflammation level. However, Rapa did not increase the phagocytic activity. Accordingly, mice with specific Mtor knockout in myeloid cells experienced more severe S. aureus pneumonia. Conclusion Rapa exacerbates S. aureus pneumonia by increasing the inflammatory levels of macrophages. Inhibition of mTOR-RPS6 pathway upregulates the expression of cytokines and chemokines in macrophages, thus increases inflammatory cells infiltration and exacerbates tissue damage.
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Affiliation(s)
- Fang-Yi Yu
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Kua Zheng
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Yin-Fang Wu
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Shen-Wei Gao
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Qing-Yu Weng
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Chen Zhu
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Yan-Ping Wu
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Miao Li
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Zhong-Nan Qin
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Jia-Fei Lou
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Zhi-Hua Chen
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Song-Min Ying
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Hua-Hao Shen
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Wen Li
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
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Li S, Chen JS, Li X, Bai X, Shi D. MNK, mTOR or eIF4E-selecting the best anti-tumor target for blocking translation initiation. Eur J Med Chem 2023; 260:115781. [PMID: 37669595 DOI: 10.1016/j.ejmech.2023.115781] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/29/2023] [Accepted: 08/29/2023] [Indexed: 09/07/2023]
Abstract
Overexpression of eIF4E is common in patients with various solid tumors and hematologic cancers. As a potential anti-cancer target, eIF4E has attracted extensive attention from researchers. At the same time, mTOR kinases inhibitors and MNK kinases inhibitors, which are directly related to regulation of eIF4E, have been rapidly developed. To explore the optimal anti-cancer targets among MNK, mTOR, and eIF4E, this review provides a detailed classification and description of the anti-cancer activities of promising compounds. In addition, the structures and activities of some dual-target inhibitors are briefly described. By analyzing the different characteristics of the inhibitors, it can be concluded that MNK1/2 and eIF4E/eIF4G interaction inhibitors are superior to mTOR inhibitors. Simultaneous inhibition of MNK and eIF4E/eIF4G interaction may be the most promising anti-cancer method for targeting translation initiation.
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Affiliation(s)
- Shuo Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, Shandong, PR China.
| | - Jia-Shu Chen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, Shandong, PR China.
| | - Xiangqian Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, Shandong, PR China.
| | - Xiaoyi Bai
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, Shandong, PR China.
| | - Dayong Shi
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, Shandong, PR China.
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33
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Yun HM, Hyun S. Role of gut commensal bacteria in juvenile developmental growth of the host: insights from Drosophila studies. Anim Cells Syst (Seoul) 2023; 27:329-339. [PMID: 38023592 PMCID: PMC10653766 DOI: 10.1080/19768354.2023.2282726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 11/07/2023] [Indexed: 12/01/2023] Open
Abstract
The gut microbiome plays a crucial role in maintaining health in a variety of organisms, from insects to humans. Further, beneficial symbiotic microbes are believed to contribute to improving the quality of life of the host. Drosophila is an optimal model for studying host-commensal microbe interactions because it allows for convenient manipulation of intestinal microbial composition. Fly microbiota has a simple taxonomic composition and can be cultivated and genetically tracked. This permits functional studies and analyses of the molecular mechanisms underlying their effects on host physiological processes. In this context, we briefly introduce the principle of juvenile developmental growth in Drosophila. Then, we discuss the current understanding of the molecular mechanisms underlying the effects of gut commensal bacteria, such as Lactiplantibacillus plantarum and Acetobacter pomorum, in the fly gut microbiome on Drosophila juvenile growth, including specific actions of gut hormones and metabolites in conserved cellular signaling systems, such as the insulin/insulin-like (IIS) and the target of rapamycin (TOR) pathways. Given the similarities in tissue function/structure, as well as the high conservation of physiological systems between Drosophila and mammals, findings from the Drosophila model system will have significant implications for understanding the mechanisms underlying the interaction between the host and the gut microbiome in metazoans.
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Affiliation(s)
- Hyun Myoung Yun
- Department of Life Science, Chung-Ang University, Seoul, South Korea
| | - Seogang Hyun
- Department of Life Science, Chung-Ang University, Seoul, South Korea
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Frappaolo A, Giansanti MG. Using Drosophila melanogaster to Dissect the Roles of the mTOR Signaling Pathway in Cell Growth. Cells 2023; 12:2622. [PMID: 37998357 PMCID: PMC10670727 DOI: 10.3390/cells12222622] [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: 10/23/2023] [Revised: 11/10/2023] [Accepted: 11/11/2023] [Indexed: 11/25/2023] Open
Abstract
The evolutionarily conserved target of rapamycin (TOR) serine/threonine kinase controls eukaryotic cell growth, metabolism and survival by integrating signals from the nutritional status and growth factors. TOR is the catalytic subunit of two distinct functional multiprotein complexes termed mTORC1 (mechanistic target of rapamycin complex 1) and mTORC2, which phosphorylate a different set of substrates and display different physiological functions. Dysregulation of TOR signaling has been involved in the development and progression of several disease states including cancer and diabetes. Here, we highlight how genetic and biochemical studies in the model system Drosophila melanogaster have been crucial to identify the mTORC1 and mTORC2 signaling components and to dissect their function in cellular growth, in strict coordination with insulin signaling. In addition, we review new findings that involve Drosophila Golgi phosphoprotein 3 in regulating organ growth via Rheb-mediated activation of mTORC1 in line with an emerging role for the Golgi as a major hub for mTORC1 signaling.
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Affiliation(s)
- Anna Frappaolo
- Istituto di Biologia e Patologia Molecolari del CNR, c/o Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, 00185 Roma, Italy
| | - Maria Grazia Giansanti
- Istituto di Biologia e Patologia Molecolari del CNR, c/o Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, 00185 Roma, Italy
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35
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Rodrigues Junior CF, Murata GM, Gerlinger-Romero F, Nachbar RT, Marzuca-Nassr GN, Gorjão R, Vitzel KF, Hirabara SM, Pithon-Curi TC, Curi R. Changes in Skeletal Muscle Protein Metabolism Signaling Induced by Glutamine Supplementation and Exercise. Nutrients 2023; 15:4711. [PMID: 38004105 PMCID: PMC10674901 DOI: 10.3390/nu15224711] [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: 08/23/2023] [Revised: 10/30/2023] [Accepted: 11/01/2023] [Indexed: 11/26/2023] Open
Abstract
AIM To evaluate the effects of resistance exercise training (RET) and/or glutamine supplementation (GS) on signaling protein synthesis in adult rat skeletal muscles. METHODS The following groups were studied: (1) control, no exercise (C); (2) exercise, hypertrophy resistance exercise training protocol (T); (3) no exercise, supplemented with glutamine (G); and (4) exercise and supplemented with glutamine (GT). The rats performed hypertrophic training, climbing a vertical ladder with a height of 1.1 m at an 80° incline relative to the horizontal with extra weights tied to their tails. The RET was performed three days a week for five weeks. Each training session consisted of six ladder climbs. The extra weight load was progressively increased for each animal during each training session. The G groups received daily L-glutamine by gavage (one g per kilogram of body weight per day) for five weeks. The C group received the same volume of water during the same period. The rats were euthanized, and the extensor digitorum longus (EDL) muscles from both hind limbs were removed and immediately weighed. Glutamine and glutamate concentrations were measured, and histological, signaling protein contents, and mRNA expression analyses were performed. RESULTS Supplementation with free L-glutamine increased the glutamine concentration in the EDL muscle in the C group. The glutamate concentration was augmented in the EDL muscles from T rats. The EDL muscle mass did not change, but a significant rise was reported in the cross-sectional area (CSA) of the fibers in the three experimental groups. The levels of the phosphorylated proteins (pAkt/Akt, pp70S6K/p70S6K, p4E-BP1/4E-BP1, and pS6/S6 ratios) were significantly increased in EDL muscles of G rats, and the activation of p4E-BP1 was present in T rats. The fiber CSAs of the EDL muscles in T, G, and GT rats were increased compared to the C group. These changes were accompanied by a reduction in the 26 proteasome activity of EDL muscles from T rats. CONCLUSION Five weeks of GS and/or RET induced muscle hypertrophy, as indicated by the increased CSAs of the EDL muscle fibers. The increase in CSA was mediated via the upregulated phosphorylation of Akt, 4E-BP1, p70S6k, and S6 in G animals and 4E-BP1 in T animals. In the EDL muscles from T animals, a decrease in proteasome activity, favoring a further increase in the CSA of the muscle fibers, was reported.
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Affiliation(s)
- Carlos Flores Rodrigues Junior
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-220, Brazil; (C.F.R.J.); (T.C.P.-C.); (R.C.)
| | - Gilson Masahiro Murata
- Divisions of Nephrology and Molecular Medicine, LIM-29, Department of Medicine, University of São Paulo, São Paulo 05508-220, Brazil;
| | | | - Renato Tadeu Nachbar
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-220, Brazil; (C.F.R.J.); (T.C.P.-C.); (R.C.)
| | - Gabriel Nasri Marzuca-Nassr
- Departamento de Ciencias de la Rehabilitación, Facultad de Medicina, Universidad de La Frontera, Temuco 4811230, Chile;
- Interuniversity Center for Healthy Aging (Code RED21993), Talca 3460000, Chile
| | - Renata Gorjão
- Interdisciplinary Post-graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo 01506-000, Brazil;
| | - Kaio Fernando Vitzel
- School of Health Sciences, Massey University (University of New Zealand), Auckland 0745, New Zealand;
| | - Sandro Massao Hirabara
- Interdisciplinary Post-graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo 01506-000, Brazil;
| | - Tania Cristina Pithon-Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-220, Brazil; (C.F.R.J.); (T.C.P.-C.); (R.C.)
- Interdisciplinary Post-graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo 01506-000, Brazil;
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-220, Brazil; (C.F.R.J.); (T.C.P.-C.); (R.C.)
- Interdisciplinary Post-graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo 01506-000, Brazil;
- Butantan Institute, São Paulo 05585-000, Brazil
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Prosseda PP, Dannewitz Prosseda S, Tran M, Liton PB, Sun Y. Crosstalk between the mTOR pathway and primary cilia in human diseases. Curr Top Dev Biol 2023; 155:1-37. [PMID: 38043949 DOI: 10.1016/bs.ctdb.2023.09.004] [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] [Indexed: 12/05/2023]
Abstract
Autophagy is a fundamental catabolic process whereby excessive or damaged cytoplasmic components are degraded through lysosomes to maintain cellular homeostasis. Studies of mTOR signaling have revealed that mTOR controls biomass generation and metabolism by modulating key cellular processes, including protein synthesis and autophagy. Primary cilia, the assembly of which depends on kinesin molecular motors, serve as sensory organelles and signaling platforms. Given these pathways' central role in maintaining cellular and physiological homeostasis, a connection between mTOR and primary cilia signaling is starting to emerge in a variety of diseases. In this review, we highlight recent advances in our understanding of the complex crosstalk between the mTOR pathway and cilia and discuss its function in the context of related diseases.
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Affiliation(s)
- Philipp P Prosseda
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, United States
| | | | - Matthew Tran
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, United States
| | - Paloma B Liton
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC, United States
| | - Yang Sun
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, United States; Palo Alto Veterans Administration Medical Center, Palo Alto, CA, United States.
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37
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Poddar NK, Khan A, Fatima F, Saxena A, Ghaley G, Khan S. Association of mTOR Pathway and Conformational Alterations in C-Reactive Protein in Neurodegenerative Diseases and Infections. Cell Mol Neurobiol 2023; 43:3815-3832. [PMID: 37665407 DOI: 10.1007/s10571-023-01402-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 08/15/2023] [Indexed: 09/05/2023]
Abstract
Inflammatory biomarkers have been very useful in detecting and monitoring inflammatory processes along with providing helpful information to select appropriate therapeutic strategies. C-reactive protein (CRP) is a nonspecific, but quite useful medical acute inflammatory biomarker and is associated with persistent chronic inflammatory processes. Several studies suggest that different levels of CRP are correlated with neurological disorders such as Alzheimer's disease (AD). However, dynamics of CRP levels have also been observed in virus/bacterial-related infections leading to inflammatory responses and this triggers mTOR-mediated pathways for neurodegeneration diseases. The biophysical structural transition from CRP to monomeric CRP (mCRP) and the significance of the ratio of CRP levels on the onset of symptoms associated with inflammatory response have been discussed. In addition, mTOR inhibitors act as immunomodulators by downregulating the expression of viral infection and can be explored as a potential therapy for neurological diseases.
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Affiliation(s)
- Nitesh Kumar Poddar
- Department of Biosciences, Manipal University Jaipur, Jaipur-Ajmer Express Highway, Dehmi Kalan, Near GVK Toll Plaza, Jaipur, Rajasthan, India, 303007.
| | - Arshma Khan
- Department of Biotechnology, Invertis University, Bareilly, Uttar Pradesh, India, 243123
| | - Falak Fatima
- Amity Institute of Biotechnology, Amity University, Uttar Pradesh, Noida, India, 201301
| | - Anshulika Saxena
- Department of Biosciences, Manipal University Jaipur, Jaipur-Ajmer Express Highway, Dehmi Kalan, Near GVK Toll Plaza, Jaipur, Rajasthan, India, 303007
| | - Garima Ghaley
- Department of Biosciences, Manipal University Jaipur, Jaipur-Ajmer Express Highway, Dehmi Kalan, Near GVK Toll Plaza, Jaipur, Rajasthan, India, 303007
| | - Shahanavaj Khan
- Department of Medical Lab Technology, Indian Institute of Health and Technology (IIHT), Deoband, Saharanpur, Uttar Pradesh, India, 247554.
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Cheng JW, Yu Y, Zong SY, Cai WW, Wang Y, Song YN, Xian H, Wei F. Berberine ameliorates collagen-induced arthritis in mice by restoring macrophage polarization via AMPK/mTORC1 pathway switching glycolytic reprogramming. Int Immunopharmacol 2023; 124:111024. [PMID: 37827054 DOI: 10.1016/j.intimp.2023.111024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 09/29/2023] [Accepted: 10/03/2023] [Indexed: 10/14/2023]
Abstract
Dysfunction of macrophage polarization majorly contributes to the progression of rheumatoid arthritis (RA). Polarization and functions of activated macrophages are closely associated with the reprogramming of intracellular metabolisms. Previously, we demonstrated that the anti-arthritis effect of berberine (BBR) in rats with adjuvant-induced arthritis (AA) may be related to AMP-activated protein kinase (AMPK) activation (a key regulator in the biological energy metabolism), and balanced macrophage polarization. However, the specific molecular mechanism of BBR in macrophage metabolism is yet to be elucidated. In this study, we clarified that BBR ameliorated articular inflammation and restored M1/M2 ratio in collagen-induced arthritis (CIA) mice in an AMPK-dependent manner. Mechanistically, BBR reversed the effects of mTORC1 agonist leucine (Leu) on regulating macrophage polarization through activation of AMPK to switch glycolytic reprogramming. Furthermore, BBR inhibition of mTORC1 rely on activation of AMPK to phosphorylate raptor and TSC2 instead of destroying its structure. Our study revealed that the activation of AMPK is required for the BBR-mediated anti-arthritis effect by downregulating mTORC1/HIF-1α and inhibiting the glycolysis in M1 macrophages.
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Affiliation(s)
- Jing-Wen Cheng
- School of Pharmacy, Bengbu Medical College, No. 2600, Donghai Avenue, Bengbu, Anhui, China
| | - Yun Yu
- School of Pharmacy, Bengbu Medical College, No. 2600, Donghai Avenue, Bengbu, Anhui, China
| | - Shi-Ye Zong
- School of Pharmacy, Bengbu Medical College, No. 2600, Donghai Avenue, Bengbu, Anhui, China
| | - Wei-Wei Cai
- School of Pharmacy, Bengbu Medical College, No. 2600, Donghai Avenue, Bengbu, Anhui, China
| | - Ying Wang
- School of Pharmacy, Bengbu Medical College, No. 2600, Donghai Avenue, Bengbu, Anhui, China; Biochemical Engineering Center of Anhui, Bengbu, Anhui, China
| | - Yi-Ning Song
- School of Pharmacy, Bengbu Medical College, No. 2600, Donghai Avenue, Bengbu, Anhui, China; Biochemical Engineering Center of Anhui, Bengbu, Anhui, China
| | - Hao Xian
- School of Pharmacy, Bengbu Medical College, No. 2600, Donghai Avenue, Bengbu, Anhui, China
| | - Fang Wei
- School of Pharmacy, Bengbu Medical College, No. 2600, Donghai Avenue, Bengbu, Anhui, China; Biochemical Engineering Center of Anhui, Bengbu, Anhui, China.
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Foltman M, Sanchez-Diaz A. TOR Complex 1: Orchestrating Nutrient Signaling and Cell Cycle Progression. Int J Mol Sci 2023; 24:15745. [PMID: 37958727 PMCID: PMC10647266 DOI: 10.3390/ijms242115745] [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: 09/01/2023] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023] Open
Abstract
The highly conserved TOR signaling pathway is crucial for coordinating cellular growth with the cell cycle machinery in eukaryotes. One of the two TOR complexes in budding yeast, TORC1, integrates environmental cues and promotes cell growth. While cells grow, they need to copy their chromosomes, segregate them in mitosis, divide all their components during cytokinesis, and finally physically separate mother and daughter cells to start a new cell cycle apart from each other. To maintain cell size homeostasis and chromosome stability, it is crucial that mechanisms that control growth are connected and coordinated with the cell cycle. Successive periods of high and low TORC1 activity would participate in the adequate cell cycle progression. Here, we review the known molecular mechanisms through which TORC1 regulates the cell cycle in the budding yeast Saccharomyces cerevisiae that have been extensively used as a model organism to understand the role of its mammalian ortholog, mTORC1.
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Affiliation(s)
- Magdalena Foltman
- Mechanisms and Regulation of Cell Division Research Unit, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, 39011 Santander, Spain
- Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, 39011 Santander, Spain
| | - Alberto Sanchez-Diaz
- Mechanisms and Regulation of Cell Division Research Unit, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, 39011 Santander, Spain
- Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, 39011 Santander, Spain
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Marafie SK, Al-Mulla F. An Overview of the Role of Furin in Type 2 Diabetes. Cells 2023; 12:2407. [PMID: 37830621 PMCID: PMC10571965 DOI: 10.3390/cells12192407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/27/2023] [Indexed: 10/14/2023] Open
Abstract
Post-translational modifications (PTMs) play important roles in regulating several human diseases, like cancer, neurodegenerative disorders, and metabolic disorders. Investigating PTMs' contribution to protein functions is critical for modern biology and medicine. Proprotein convertases (PCs) are irreversible post-translational modifiers that have been extensively studied and are considered as key targets for novel therapeutics. They cleave proteins at specific sites causing conformational changes affecting their functions. Furin is considered as a PC model in regulating growth factors and is involved in regulating many pro-proteins. The mammalian target of the rapamycin (mTOR) signaling pathway is another key player in regulating cellular processes and its dysregulation is linked to several diseases including type 2 diabetes (T2D). The role of furin in the context of diabetes has been rarely explored and is currently lacking. Moreover, furin variants have altered activity that could have implications on overall health. In this review, we aim to highlight the role of furin in T2D in relation to mTOR signaling. We will also address furin genetic variants and their potential effect on T2D and β-cell functions. Understanding the role of furin in prediabetes and dissecting it from other confounding factors like obesity is crucial for future therapeutic interventions in metabolic disorders.
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Affiliation(s)
- Sulaiman K. Marafie
- Biochemistry and Molecular Biology Department, Dasman Diabetes Institute, P.O. Box 1180, Dasman 15462, Kuwait
| | - Fahd Al-Mulla
- Genetics and Bioinformatics Department, Dasman Diabetes Institute, P.O. Box 1180, Dasman 15462, Kuwait
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Panwar V, Singh A, Bhatt M, Tonk RK, Azizov S, Raza AS, Sengupta S, Kumar D, Garg M. Multifaceted role of mTOR (mammalian target of rapamycin) signaling pathway in human health and disease. Signal Transduct Target Ther 2023; 8:375. [PMID: 37779156 PMCID: PMC10543444 DOI: 10.1038/s41392-023-01608-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 07/25/2023] [Accepted: 08/14/2023] [Indexed: 10/03/2023] Open
Abstract
The mammalian target of rapamycin (mTOR) is a protein kinase that controls cellular metabolism, catabolism, immune responses, autophagy, survival, proliferation, and migration, to maintain cellular homeostasis. The mTOR signaling cascade consists of two distinct multi-subunit complexes named mTOR complex 1/2 (mTORC1/2). mTOR catalyzes the phosphorylation of several critical proteins like AKT, protein kinase C, insulin growth factor receptor (IGF-1R), 4E binding protein 1 (4E-BP1), ribosomal protein S6 kinase (S6K), transcription factor EB (TFEB), sterol-responsive element-binding proteins (SREBPs), Lipin-1, and Unc-51-like autophagy-activating kinases. mTOR signaling plays a central role in regulating translation, lipid synthesis, nucleotide synthesis, biogenesis of lysosomes, nutrient sensing, and growth factor signaling. The emerging pieces of evidence have revealed that the constitutive activation of the mTOR pathway due to mutations/amplification/deletion in either mTOR and its complexes (mTORC1 and mTORC2) or upstream targets is responsible for aging, neurological diseases, and human malignancies. Here, we provide the detailed structure of mTOR, its complexes, and the comprehensive role of upstream regulators, as well as downstream effectors of mTOR signaling cascades in the metabolism, biogenesis of biomolecules, immune responses, and autophagy. Additionally, we summarize the potential of long noncoding RNAs (lncRNAs) as an important modulator of mTOR signaling. Importantly, we have highlighted the potential of mTOR signaling in aging, neurological disorders, human cancers, cancer stem cells, and drug resistance. Here, we discuss the developments for the therapeutic targeting of mTOR signaling with improved anticancer efficacy for the benefit of cancer patients in clinics.
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Affiliation(s)
- Vivek Panwar
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Shoolini University, Solan, Himachal Pradesh, 173229, India
| | - Aishwarya Singh
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Uttar Pradesh, Sector-125, Noida, Uttar Pradesh, 201313, India
| | - Manini Bhatt
- Department of Biomedical Engineering, Indian Institute of Technology, Ropar, Punjab, 140001, India
| | - Rajiv K Tonk
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Delhi Pharmaceutical Sciences and Research University (DPSRU), New Delhi, 110017, India
| | - Shavkatjon Azizov
- Laboratory of Biological Active Macromolecular Systems, Institute of Bioorganic Chemistry, Academy of Sciences Uzbekistan, Tashkent, 100125, Uzbekistan
- Faculty of Life Sciences, Pharmaceutical Technical University, 100084, Tashkent, Uzbekistan
| | - Agha Saquib Raza
- Rajive Gandhi Super Speciality Hospital, Tahirpur, New Delhi, 110093, India
| | - Shinjinee Sengupta
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Uttar Pradesh, Sector-125, Noida, Uttar Pradesh, 201313, India.
| | - Deepak Kumar
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Shoolini University, Solan, Himachal Pradesh, 173229, India.
| | - Manoj Garg
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Uttar Pradesh, Sector-125, Noida, Uttar Pradesh, 201313, India.
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Ren W, Chen L. Integrated Transcriptome and Metabolome Analysis of Salinity Tolerance in Response to Foliar Application of β-Alanine in Cotton Seedlings. Genes (Basel) 2023; 14:1825. [PMID: 37761965 PMCID: PMC10531431 DOI: 10.3390/genes14091825] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/17/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023] Open
Abstract
Salinity is amongst the serious abiotic stresses cotton plants face, impairing crop productivity. Foliar application of β-alanine is employed to improve salt tolerance in various crops, but the exact mechanism behind it is not yet completely understood. An advanced line SDS-01 of upland cotton Gossypium hirsutum L. was utilized to determine its salt tolerance. Foliar treatment with the β-alanine solution at different concentrations was applied to the seedlings stressed with 0.8% NaCl solution. On the 10th day of treatment, samples were collected for transcriptome and metabolome analyses. β-alanine solution at a concentration of 25 mM was found to be the best treatment with the lowest mortality rate and highest plant height and above-ground biomass under salt stress. Both differentially expressed genes and accumulated metabolites analyses showed improved tolerance of treated seedlings. The photosynthetic efficiency improved in seedlings due to higher expression of photosynthesis-antenna proteins and activation of hormones signal transduction after treatment with β-alanine. Highly expressed transcription factors observed were MYB, HD-ZIP, ARF, MYC, EREB, DELLA, ABF, H2A, H4, WRKY, and HK involved in the positive regulation of salinity tolerance in β-alanine-treated seedlings. Furthermore, compared to the control, the high accumulation of polyamines, coumarins, organic acids, and phenolic compounds in the β-alanine-treated seedlings helped regulate cellular antioxidant (glutathione and L-Cysteine) production. Hence, to improve salt tolerance and productivity in cotton, foliar application of β-alanine at the seedling stage can be a valuable management practice.
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Affiliation(s)
- Wei Ren
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China;
- Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China
| | - Li Chen
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China;
- Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China
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Fu Y, Fu Z, Su Z, Li L, Yang Y, Tan Y, Xiang Y, Shi Y, Xie S, Sun L, Peng G. mLST8 is essential for coronavirus replication and regulates its replication through the mTORC1 pathway. mBio 2023; 14:e0089923. [PMID: 37377422 PMCID: PMC10470783 DOI: 10.1128/mbio.00899-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 05/11/2023] [Indexed: 06/29/2023] Open
Abstract
Coronaviruses (CoVs), which pose a serious threat to human and animal health worldwide, need to hijack host factors to complete their replicative cycles. However, the current study of host factors involved in CoV replication remains unknown. Here, we identified a novel host factor, mammalian lethal with sec-13 protein 8 (mLST8), which is a common subunit of mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2), and is critical for CoV replication. Inhibitor and knockout (KO) experiments revealed that mTORC1, but not mTORC2, is essential for transmissible gastroenteritis virus replication. Furthermore, mLST8 KO reduced the phosphorylation of unc-51-like kinase 1 (ULK1), a factor downstream of the mTORC1 signaling pathway, and mechanistic studies revealed that decreased phosphorylation of the mTORC1 downstream factor ULK1 promoted the activation of autophagy, which is responsible for antiviral replication in mLST8 KO cells. Then, transmission electron microscopy indicated that both mLST8 KO and autophagy activator inhibited the formation of double-membrane vesicles in early viral replication. Finally, mLST8 KO and autophagy activator treatment could also inhibit the replication of other CoVs, indicating a conserved relationship between autophagy activation and CoV replication. In summary, our work reveals that mLST8 is a novel host regulator of CoV replication, which provides new insights into the mechanism of CoV replication and can facilitate the development of broad-spectrum antiviral drugs. IMPORTANCE CoVs are highly variable, and existing CoV vaccines are still limited in their ability to address mutations in CoVs. Therefore, the need to improve our understanding of the interaction of CoVs with the host during viral replication and to find targets for drugs against CoVs is urgent. Here, we found that a novel host factor, mLST8, is critical for CoV infection. Further studies showed that mLST8 KO inhibited the mTORC1 signaling pathway, and we found that autophagy activation downstream of mTORC1 was the main cause of antiviral replication in mLST8 KO cells. Autophagy activation impaired the formation of DMVs and inhibited early viral replication. These findings deepen our understanding of the CoV replication process and provide insights into potential therapeutic applications.
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Affiliation(s)
- Yanan Fu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Zhen Fu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Zhelin Su
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Lisha Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Yilin Yang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Yubei Tan
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Yixin Xiang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Yuejun Shi
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Shengsong Xie
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, China
| | - Limeng Sun
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Guiqing Peng
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Wuhan, China
- Hubei Hongshan Laboratory, Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan, China
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Xu C, Pan X, Wang D, Guan Y, Yang W, Chen X, Liu Y. O-GlcNAcylation of Raptor transduces glucose signals to mTORC1. Mol Cell 2023; 83:3027-3040.e11. [PMID: 37541260 DOI: 10.1016/j.molcel.2023.07.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 05/23/2023] [Accepted: 07/11/2023] [Indexed: 08/06/2023]
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) regulates metabolism and cell growth in response to nutrient levels. Dysregulation of mTORC1 results in a broad spectrum of diseases. Glucose is the primary energy supply of cells, and therefore, glucose levels must be accurately conveyed to mTORC1 through highly responsive signaling mechanisms to control mTORC1 activity. Here, we report that glucose-induced mTORC1 activation is regulated by O-GlcNAcylation of Raptor, a core component of mTORC1, in HEK293T cells. Mechanistically, O-GlcNAcylation of Raptor at threonine 700 facilitates the interactions between Raptor and Rag GTPases and promotes the translocation of mTOR to the lysosomal surface, consequently activating mTORC1. In addition, we show that AMPK-mediated phosphorylation of Raptor suppresses Raptor O-GlcNAcylation and inhibits Raptor-Rags interactions. Our findings reveal an exquisitely controlled mechanism, which suggests how glucose coordinately regulates cellular anabolism and catabolism.
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Affiliation(s)
- Chenchen Xu
- State Key Laboratory of Membrane Biology, New Cornerstone Science Laboratory, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Xiaoqing Pan
- College of Chemistry and Molecular Engineering, Peking University, Beijing, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Dong Wang
- State Key Laboratory of Membrane Biology, New Cornerstone Science Laboratory, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Yuanyuan Guan
- State Key Laboratory of Membrane Biology, New Cornerstone Science Laboratory, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Wenyu Yang
- Yuan Pei College, Peking University, Beijing 100871, China
| | - Xing Chen
- College of Chemistry and Molecular Engineering, Peking University, Beijing, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China; Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China; Synthetic and Functional Biomolecules Center, Peking University, Beijing 100871, China; Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Peking University, Beijing 100871, China.
| | - Ying Liu
- State Key Laboratory of Membrane Biology, New Cornerstone Science Laboratory, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China; Beijing Advanced Innovation Center for Genomics, Beijing 100871, China.
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Tribble JR, Hui F, Quintero H, El Hajji S, Bell K, Di Polo A, Williams PA. Neuroprotection in glaucoma: Mechanisms beyond intraocular pressure lowering. Mol Aspects Med 2023; 92:101193. [PMID: 37331129 DOI: 10.1016/j.mam.2023.101193] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/25/2023] [Accepted: 06/04/2023] [Indexed: 06/20/2023]
Abstract
Glaucoma is a common, complex, multifactorial neurodegenerative disease characterized by progressive dysfunction and then loss of retinal ganglion cells, the output neurons of the retina. Glaucoma is the most common cause of irreversible blindness and affects ∼80 million people worldwide with many more undiagnosed. The major risk factors for glaucoma are genetics, age, and elevated intraocular pressure. Current strategies only target intraocular pressure management and do not directly target the neurodegenerative processes occurring at the level of the retinal ganglion cell. Despite strategies to manage intraocular pressure, as many as 40% of glaucoma patients progress to blindness in at least one eye during their lifetime. As such, neuroprotective strategies that target the retinal ganglion cell and these neurodegenerative processes directly are of great therapeutic need. This review will cover the recent advances from basic biology to on-going clinical trials for neuroprotection in glaucoma covering degenerative mechanisms, metabolism, insulin signaling, mTOR, axon transport, apoptosis, autophagy, and neuroinflammation. With an increased understanding of both the basic and clinical mechanisms of the disease, we are closer than ever to a neuroprotective strategy for glaucoma.
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Affiliation(s)
- James R Tribble
- Department of Clinical Neuroscience, Division of Eye and Vision, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Flora Hui
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia; Department of Optometry & Vision Sciences, The University of Melbourne, Melbourne, Australia
| | - Heberto Quintero
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Sana El Hajji
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Katharina Bell
- NHMRC Clinical Trials Centre, University of Sydney, Australia; Eye ACP Duke-NUS, Singapore
| | - Adriana Di Polo
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Pete A Williams
- Department of Clinical Neuroscience, Division of Eye and Vision, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden.
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Shi F, de Fatima Silva F, Liu D, Patel HU, Xu J, Zhang W, Türk C, Krüger M, Collins S. Salt-inducible kinase inhibition promotes the adipocyte thermogenic program and adipose tissue browning. Mol Metab 2023; 74:101753. [PMID: 37321371 PMCID: PMC10319839 DOI: 10.1016/j.molmet.2023.101753] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 05/30/2023] [Accepted: 06/08/2023] [Indexed: 06/17/2023] Open
Abstract
OBJECTIVE Norepinephrine stimulates the adipose tissue thermogenic program through a β-adrenergic receptor (βAR)-cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signaling cascade. We discovered that a noncanonical activation of the mechanistic target of rapamycin complex 1 (mTORC1) by PKA is required for the βAR-stimulation of adipose tissue browning. However, the downstream events triggered by PKA-phosphorylated mTORC1 activation that drive this thermogenic response are not well understood. METHODS We used a proteomic approach of Stable Isotope Labeling by/with Amino acids in Cell culture (SILAC) to characterize the global protein phosphorylation profile in brown adipocytes treated with the βAR agonist. We identified salt-inducible kinase 3 (SIK3) as a candidate mTORC1 substrate and further tested the effect of SIK3 deficiency or SIK inhibition on the thermogenic gene expression program in brown adipocytes and in mouse adipose tissue. RESULTS SIK3 interacts with RAPTOR, the defining component of the mTORC1 complex, and is phosphorylated at Ser884 in a rapamycin-sensitive manner. Pharmacological SIK inhibition by a pan-SIK inhibitor (HG-9-91-01) in brown adipocytes increases basal Ucp1 gene expression and restores its expression upon blockade of either mTORC1 or PKA. Short-hairpin RNA (shRNA) knockdown of Sik3 augments, while overexpression of SIK3 suppresses, Ucp1 gene expression in brown adipocytes. The regulatory PKA phosphorylation domain of SIK3 is essential for its inhibition. CRISPR-mediated Sik3 deletion in brown adipocytes increases type IIa histone deacetylase (HDAC) activity and enhances the expression of genes involved in thermogenesis such as Ucp1, Pgc1α, and mitochondrial OXPHOS complex protein. We further show that HDAC4 interacts with PGC1α after βAR stimulation and reduces lysine acetylation in PGC1α. Finally, a SIK inhibitor well-tolerated in vivo (YKL-05-099) can stimulate the expression of thermogenesis-related genes and browning of mouse subcutaneous adipose tissue. CONCLUSIONS Taken together, our data reveal that SIK3, with the possible contribution of other SIKs, functions as a phosphorylation switch for β-adrenergic activation to drive the adipose tissue thermogenic program and indicates that more work to understand the role of the SIKs is warranted. Our findings also suggest that maneuvers targeting SIKs could be beneficial for obesity and related cardiometabolic disease.
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Affiliation(s)
- Fubiao Shi
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
| | - Flaviane de Fatima Silva
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo 05508-000, Brazil
| | - Dianxin Liu
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Hari U Patel
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jonathan Xu
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Wei Zhang
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Clara Türk
- CECAD Research Center, Institute for Genetics, University of Cologne, Cologne 50931, Germany
| | - Marcus Krüger
- CECAD Research Center, Institute for Genetics, University of Cologne, Cologne 50931, Germany; Center for Molecular Medicine (CMMC), University of Cologne, Cologne 50931, Germany
| | - Sheila Collins
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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Zhang X, Evans TD, Chen S, Sergin I, Stitham J, Jeong SJ, Rodriguez-Velez A, Yeh YS, Park A, Jung IH, Diwan A, Schilling JD, Rom O, Yurdagul A, Epelman S, Cho J, Lodhi IJ, Mittendorfer B, Razani B. Loss of Macrophage mTORC2 Drives Atherosclerosis via FoxO1 and IL-1β Signaling. Circ Res 2023; 133:200-219. [PMID: 37350264 PMCID: PMC10527041 DOI: 10.1161/circresaha.122.321542] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 06/12/2023] [Indexed: 06/24/2023]
Abstract
BACKGROUND The mTOR (mechanistic target of rapamycin) pathway is a complex signaling cascade that regulates cellular growth, proliferation, metabolism, and survival. Although activation of mTOR signaling has been linked to atherosclerosis, its direct role in lesion progression and in plaque macrophages remains poorly understood. We previously demonstrated that mTORC1 (mTOR complex 1) activation promotes atherogenesis through inhibition of autophagy and increased apoptosis in macrophages. METHODS Using macrophage-specific Rictor- and mTOR-deficient mice, we now dissect the distinct functions of mTORC2 pathways in atherogenesis. RESULTS In contrast to the atheroprotective effect seen with blockade of macrophage mTORC1, macrophage-specific mTORC2-deficient mice exhibit an atherogenic phenotype, with larger, more complex lesions and increased cell death. In cultured macrophages, we show that mTORC2 signaling inhibits the FoxO1 (forkhead box protein O1) transcription factor, leading to suppression of proinflammatory pathways, especially the inflammasome/IL (interleukin)-1β response, a key mediator of vascular inflammation and atherosclerosis. In addition, administration of FoxO1 inhibitors efficiently rescued the proinflammatory response caused by mTORC2 deficiency both in vitro and in vivo. Interestingly, collective deletion of macrophage mTOR, which ablates mTORC1- and mTORC2-dependent pathways, leads to minimal change in plaque size or complexity, reflecting the balanced yet opposing roles of these signaling arms. CONCLUSIONS Our data provide the first mechanistic details of macrophage mTOR signaling in atherosclerosis and suggest that therapeutic measures aimed at modulating mTOR need to account for its dichotomous functions.
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Affiliation(s)
- Xiangyu Zhang
- Department of Medicine and Vascular Medicine Institute, University of Pittsburgh School of Medicine and UPMC, Pittsburgh, PA
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
| | - Trent D. Evans
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
| | - Sunny Chen
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
| | - Ismail Sergin
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
| | - Jeremiah Stitham
- Division of Endocrinology, Metabolism, and Lipid Research, Washington University School of Medicine, St Louis, MO, USA
| | - Se-Jin Jeong
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
| | | | - Yu-Sheng Yeh
- Department of Medicine and Vascular Medicine Institute, University of Pittsburgh School of Medicine and UPMC, Pittsburgh, PA
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
| | - Arick Park
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
| | - In-Hyuk Jung
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
| | - Abhinav Diwan
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
- John Cochran VA Medical Center, St. Louis, MO, USA
| | - Joel D. Schilling
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
| | - Oren Rom
- Department of Pathology and Translational Pathobiology and Department of Molecular and Cellular Physiology, Louisiana State University, Shreveport, LA
| | - Arif Yurdagul
- Department of Pathology and Translational Pathobiology and Department of Molecular and Cellular Physiology, Louisiana State University, Shreveport, LA
| | - Slava Epelman
- Ted Rogers Centre for Heart Research, Peter Munk Cardiac Center, Toronto General Hospital Research Institute, University Health Network and University of Toronto, Toronto, Canada
| | - Jaehyung Cho
- Division of Hematology, Department of Medicine, Washington University School of Medicine, St Louis, MO, USA
- Department of Pathology & Immunology, Washington University School of Medicine, St Louis, MO, USA
| | - Irfan J. Lodhi
- Division of Endocrinology, Metabolism, and Lipid Research, Washington University School of Medicine, St Louis, MO, USA
| | - Bettina Mittendorfer
- Division of Geriatrics and Nutritional Science, and Washington University School of Medicine, St Louis, MO, USA
| | - Babak Razani
- Department of Medicine and Vascular Medicine Institute, University of Pittsburgh School of Medicine and UPMC, Pittsburgh, PA
- Pittsburgh VA Medical Center, Pittsburgh, PA
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA
- Department of Pathology & Immunology, Washington University School of Medicine, St Louis, MO, USA
- John Cochran VA Medical Center, St. Louis, MO, USA
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Santiago NA, He B, Howard SL, Beaudin S, Strupp BJ, Smith DR. Developmental Manganese Exposure Causes Lasting Attention Deficits Accompanied by Dysregulation of mTOR Signaling and Catecholaminergic Gene Expression in Brain Prefrontal Cortex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.16.549215. [PMID: 37503220 PMCID: PMC10370122 DOI: 10.1101/2023.07.16.549215] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Elevated manganese (Mn) exposure is associated with attentional deficits in children, and is an environmental risk factor for attention deficit hyperactivity disorder (ADHD). We have shown that developmental Mn exposure causes lasting attention and sensorimotor deficits in a rat model of early childhood Mn exposure, and that these deficits are associated with a hypofunctioning catecholaminergic system in the prefrontal cortex (PFC), though the mechanistic basis for these deficits is not well understood. To address this, male Long-Evans rats were exposed orally to Mn (50 mg/kg/d) over PND 1-21 and attentional function was assessed in adulthood using the 5-Choice Serial Reaction Time Task. Targeted catecholaminergic system and epigenetic gene expression, followed by unbiased differential DNA methylation and gene regulation expression transcriptomics in the PFC, were performed in young adult littermates. Results show that developmental Mn exposure causes lasting focused attention deficits that are associated with reduced gene expression of tyrosine hydroxylase, dopamine transporter, and DNA methyltransferase 3a. Further, developmental Mn exposure causes broader lasting methylation and gene expression dysregulation associated with epigenetic regulation, inflammation, cell development, and hypofunctioning catecholaminergic neuronal systems. Pathway enrichment analyses uncovered mTOR and Wnt signaling pathway genes as significant transcriptomic regulators of the Mn altered transcriptome, and Western blot of total, C1 and C2 phospho-mTOR confirmed mTOR pathway dysregulation. Our findings deepen our understanding of the mechanistic basis of how developmental Mn exposure leads to lasting catecholaminergic dysfunction and attention deficits, which may aid future therapeutic interventions of environmental exposure associated disorders. Significance Statement Attention deficit hyperactivity disorder (ADHD) is associated with environmental risk factors, including exposure to neurotoxic agents. Here we used a rodent model of developmental manganese (Mn) exposure producing lasting attention deficits to show broad epigenetic and gene expression changes in the prefrontal cortex, and to identify disrupted mTOR and Wnt signaling pathways as a novel mechanism for how developmental Mn exposure may induce lasting attention and catecholaminergic system impairments. Importantly, our findings establish early development as a critical period of susceptibility to lasting deficits in attentional function caused by elevated environmental toxicant exposure. Given that environmental health threats disproportionately impact communities of color and low socioeconomic status, our findings can aid future studies to assess therapeutic interventions for vulnerable populations.
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Jeong MH, Urquhart G, Lewis C, Chi Z, Jewell JL. Inhibition of phosphodiesterase 4D suppresses mTORC1 signaling and pancreatic cancer growth. JCI Insight 2023; 8:e158098. [PMID: 37427586 PMCID: PMC10371348 DOI: 10.1172/jci.insight.158098] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 05/23/2023] [Indexed: 07/11/2023] Open
Abstract
The mammalian target of rapamycin complex 1 (mTORC1) senses multiple upstream stimuli to orchestrate anabolic and catabolic events that regulate cell growth and metabolism. Hyperactivation of mTORC1 signaling is observed in multiple human diseases; thus, pathways that suppress mTORC1 signaling may help to identify new therapeutic targets. Here, we report that phosphodiesterase 4D (PDE4D) promotes pancreatic cancer tumor growth by increasing mTORC1 signaling. GPCRs paired to Gαs proteins activate adenylyl cyclase, which in turn elevates levels of 3',5'-cyclic adenosine monophosphate (cAMP), whereas PDEs catalyze the hydrolysis of cAMP to 5'-AMP. PDE4D forms a complex with mTORC1 and is required for mTORC1 lysosomal localization and activation. Inhibition of PDE4D and the elevation of cAMP levels block mTORC1 signaling via Raptor phosphorylation. Moreover, pancreatic cancer exhibits an upregulation of PDE4D expression, and high PDE4D levels predict the poor overall survival of patients with pancreatic cancer. Importantly, FDA-approved PDE4 inhibitors repress pancreatic cancer cell tumor growth in vivo by suppressing mTORC1 signaling. Our results identify PDE4D as an important activator of mTORC1 and suggest that targeting PDE4 with FDA-approved inhibitors may be beneficial for the treatment of human diseases with hyperactivated mTORC1 signaling.
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Affiliation(s)
- Mi-Hyeon Jeong
- Department of Molecular Biology
- Harold C. Simmons Comprehensive Cancer Center
- Hamon Center for Regenerative Science and Medicine, and
| | - Greg Urquhart
- Department of Molecular Biology
- Harold C. Simmons Comprehensive Cancer Center
- Hamon Center for Regenerative Science and Medicine, and
| | | | - Zhikai Chi
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Jenna L Jewell
- Department of Molecular Biology
- Harold C. Simmons Comprehensive Cancer Center
- Hamon Center for Regenerative Science and Medicine, and
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Xu J, Velleman SG. Critical role of the mTOR pathway in poultry skeletal muscle physiology and meat quality: an opinion paper. Front Physiol 2023; 14:1228318. [PMID: 37476689 PMCID: PMC10354517 DOI: 10.3389/fphys.2023.1228318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 06/27/2023] [Indexed: 07/22/2023] Open
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