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Kim S, Bhandari R, Brearley CA, Saiardi A. The inositol phosphate signalling network in physiology and disease. Trends Biochem Sci 2024:S0968-0004(24)00192-0. [PMID: 39317578 DOI: 10.1016/j.tibs.2024.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 07/29/2024] [Accepted: 08/19/2024] [Indexed: 09/26/2024]
Abstract
Combinatorial substitution of phosphate groups on the inositol ring gives rise to a plethora of inositol phosphates (InsPs) and inositol pyrophosphates (PP-InsPs). These small molecules constitute an elaborate metabolic and signalling network that influences nearly every cellular function. This review delves into the knowledge accumulated over the past decades regarding the biochemical principles and significance of InsP metabolism. We focus on the biological actions of InsPs in mammals, with an emphasis on recent findings regarding specific target proteins. We further discuss the roles of InsP metabolism in contributing to physiological homeostasis and pathological conditions. A deeper understanding of InsPs and their metabolic pathways holds the potential to address unresolved questions and propel advances towards therapeutic applications.
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Affiliation(s)
- Seyun Kim
- Department of Biological Sciences, KAIST Stem Cell Center, KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
| | - Rashna Bhandari
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics (CDFD), Inner Ring Road, Uppal, Hyderabad 500039, India.
| | - Charles A Brearley
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
| | - Adolfo Saiardi
- Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK.
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2
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Jones GD, Ellisdon AM. Understanding P-Rex regulation: structural breakthroughs and emerging perspectives. Biochem Soc Trans 2024; 52:1849-1860. [PMID: 39023851 DOI: 10.1042/bst20231546] [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: 05/28/2024] [Revised: 07/02/2024] [Accepted: 07/08/2024] [Indexed: 07/20/2024]
Abstract
Rho GTPases are a family of highly conserved G proteins that regulate numerous cellular processes, including cytoskeleton organisation, migration, and proliferation. The 20 canonical Rho GTPases are regulated by ∼85 guanine nucleotide exchange factors (GEFs), with the largest family being the 71 Diffuse B-cell Lymphoma (Dbl) GEFs. Dbl GEFs promote GTPase activity through the highly conserved Dbl homology domain. The specificity of GEF activity, and consequently GTPase activity, lies in the regulation and structures of the GEFs themselves. Dbl GEFs contain various accessory domains that regulate GEF activity by controlling subcellular localisation, protein interactions, and often autoinhibition. This review focuses on the two phosphatidylinositol (3,4,5)-trisphosphate (PI(3,4,5)P3)-dependent Rac exchangers (P-Rex), particularly the structural basis of P-Rex1 autoinhibition and synergistic activation. First, we discuss structures that highlight the conservation of P-Rex catalytic and phosphoinositide binding activities. We then explore recent breakthroughs in uncovering the structural basis for P-Rex1 autoinhibition and detail the proposed minimal two-step model of how PI(3,4,5)P3 and Gβγ synergistically activate P-Rex1 at the membrane. Additionally, we discuss the further layers of P-Rex regulation provided by phosphorylation and P-Rex2-PTEN coinhibitory complex formation, although these mechanisms remain incompletely understood. Finally, we leverage the available data to infer how cancer-associated mutations in P-Rex2 destabilise autoinhibition and evade PTEN coinhibitory complex formation, leading to increased P-Rex2 GEF activity and driving cancer progression and metastasis.
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Affiliation(s)
- Gareth D Jones
- Cancer Program, Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
| | - Andrew M Ellisdon
- Cancer Program, Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
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3
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Zdanowicz R, Afanasyev P, Pruška A, Harrison JA, Giese C, Boehringer D, Leitner A, Zenobi R, Glockshuber R. Stoichiometry and architecture of the human pyruvate dehydrogenase complex. SCIENCE ADVANCES 2024; 10:eadn4582. [PMID: 39018392 PMCID: PMC466950 DOI: 10.1126/sciadv.adn4582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 06/05/2024] [Indexed: 07/19/2024]
Abstract
The pyruvate dehydrogenase complex (PDHc) is a key megaenzyme linking glycolysis with the citric acid cycle. In mammalian PDHc, dihydrolipoamide acetyltransferase (E2) and the dihydrolipoamide dehydrogenase-binding protein (E3BP) form a 60-subunit core that associates with the peripheral subunits pyruvate dehydrogenase (E1) and dihydrolipoamide dehydrogenase (E3). The structure and stoichiometry of the fully assembled, mammalian PDHc or its core remained elusive. Here, we demonstrate that the human PDHc core is formed by 48 E2 copies that bind 48 E1 heterotetramers and 12 E3BP copies that bind 12 E3 homodimers. Cryo-electron microscopy, together with native and cross-linking mass spectrometry, confirmed a core model in which 8 E2 homotrimers and 12 E2-E2-E3BP heterotrimers assemble into a pseudoicosahedral particle such that the 12 E3BP molecules form six E3BP-E3BP intertrimer interfaces distributed tetrahedrally within the 60-subunit core. The even distribution of E3 subunits in the peripheral shell of PDHc guarantees maximum enzymatic activity of the megaenzyme.
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Affiliation(s)
- Rafal Zdanowicz
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093 Zürich, Switzerland
| | - Pavel Afanasyev
- Cryo-EM Knowledge Hub, ETH Zurich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
| | - Adam Pruška
- Department of Chemistry and Applied Biosciences, Laboratory of Organic Chemistry, ETH Zurich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Julian A. Harrison
- Department of Chemistry and Applied Biosciences, Laboratory of Organic Chemistry, ETH Zurich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Christoph Giese
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093 Zürich, Switzerland
| | - Daniel Boehringer
- Cryo-EM Knowledge Hub, ETH Zurich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
| | - Alexander Leitner
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
| | - Renato Zenobi
- Department of Chemistry and Applied Biosciences, Laboratory of Organic Chemistry, ETH Zurich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Rudi Glockshuber
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093 Zürich, Switzerland
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4
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Wang Y, Vandewalle N, De Veirman K, Vanderkerken K, Menu E, De Bruyne E. Targeting mTOR signaling pathways in multiple myeloma: biology and implication for therapy. Cell Commun Signal 2024; 22:320. [PMID: 38862983 PMCID: PMC11165851 DOI: 10.1186/s12964-024-01699-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 06/03/2024] [Indexed: 06/13/2024] Open
Abstract
Multiple Myeloma (MM), a cancer of terminally differentiated plasma cells, is the second most prevalent hematological malignancy and is incurable due to the inevitable development of drug resistance. Intense protein synthesis is a distinctive trait of MM cells, supporting the massive production of clonal immunoglobulins or free light chains. The mammalian target of rapamycin (mTOR) kinase is appreciated as a master regulator of vital cellular processes, including regulation of metabolism and protein synthesis, and can be found in two multiprotein complexes, mTORC1 and mTORC2. Dysregulation of these complexes is implicated in several types of cancer, including MM. Since mTOR has been shown to be aberrantly activated in a large portion of MM patients and to play a role in stimulating MM cell survival and resistance to several existing therapies, understanding the regulation and functions of the mTOR complexes is vital for the development of more effective therapeutic strategies. This review provides a general overview of the mTOR pathway, discussing key discoveries and recent insights related to the structure and regulation of mTOR complexes. Additionally, we highlight findings on the mechanisms by which mTOR is involved in protein synthesis and delve into mTOR-mediated processes occurring in MM. Finally, we summarize the progress and current challenges of drugs targeting mTOR complexes in MM.
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Affiliation(s)
- Yanmeng Wang
- Translational Oncology Research Center (TORC) - Team Hematology and Immunology (HEIM), Vrije Universiteit Brussel (VUB), Jette, Belgium
| | - Niels Vandewalle
- Translational Oncology Research Center (TORC) - Team Hematology and Immunology (HEIM), Vrije Universiteit Brussel (VUB), Jette, Belgium
| | - Kim De Veirman
- Translational Oncology Research Center (TORC) - Team Hematology and Immunology (HEIM), Vrije Universiteit Brussel (VUB), Jette, Belgium
- Translational Oncology Research Center (TORC) - Team Hematology and Immunology (HEIM), Universitair Ziekenhuis Brussel (UZ Brussel), Jette, Belgium
| | - Karin Vanderkerken
- Translational Oncology Research Center (TORC) - Team Hematology and Immunology (HEIM), Vrije Universiteit Brussel (VUB), Jette, Belgium
| | - Eline Menu
- Translational Oncology Research Center (TORC) - Team Hematology and Immunology (HEIM), Vrije Universiteit Brussel (VUB), Jette, Belgium.
| | - Elke De Bruyne
- Translational Oncology Research Center (TORC) - Team Hematology and Immunology (HEIM), Vrije Universiteit Brussel (VUB), Jette, Belgium.
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5
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Hablase R, Kyrou I, Randeva H, Karteris E, Chatterjee J. The "Road" to Malignant Transformation from Endometriosis to Endometriosis-Associated Ovarian Cancers (EAOCs): An mTOR-Centred Review. Cancers (Basel) 2024; 16:2160. [PMID: 38893278 PMCID: PMC11172073 DOI: 10.3390/cancers16112160] [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: 04/19/2024] [Revised: 05/29/2024] [Accepted: 06/01/2024] [Indexed: 06/21/2024] Open
Abstract
Ovarian cancer is an umbrella term covering a number of distinct subtypes. Endometrioid and clear-cell ovarian carcinoma are endometriosis-associated ovarian cancers (EAOCs) frequently arising from ectopic endometrium in the ovary. The mechanistic target of rapamycin (mTOR) is a crucial regulator of cellular homeostasis and is dysregulated in both endometriosis and endometriosis-associated ovarian cancer, potentially favouring carcinogenesis across a spectrum from benign disease with cancer-like characteristics, through an atypical phase, to frank malignancy. In this review, we focus on mTOR dysregulation in endometriosis and EAOCs, investigating cancer driver gene mutations and their potential interaction with the mTOR pathway. Additionally, we explore the complex pathogenesis of transformation, considering environmental, hormonal, and epigenetic factors. We then discuss postmenopausal endometriosis pathogenesis and propensity for malignant transformation. Finally, we summarize the current advancements in mTOR-targeted therapeutics for endometriosis and EAOCs.
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Affiliation(s)
- Radwa Hablase
- College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge UB83PH, UK; (R.H.); (E.K.)
- Academic Department of Gynaecological Oncology, Royal Surrey NHS Foundation Trust Hospital, Guildford GU2 7XX, UK
| | - Ioannis Kyrou
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM), University Hospitals Coventry and Warwickshire NHS Trust, Coventry CV2 2DX, UK (H.R.)
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
- Institute for Cardiometabolic Medicine, University Hospitals Coventry and Warwickshire NHS Trust, Coventry CV2 2DX, UK
- Centre for Sport, Exercise and Life Sciences, Research Institute for Health & Wellbeing, Coventry University, Coventry CV1 5FB, UK
- Aston Medical School, College of Health and Life Sciences, Aston University, Birmingham B4 7ET, UK
- College of Health, Psychology and Social Care, University of Derby, Derby DE22 1GB, UK
- Laboratory of Dietetics and Quality of Life, Department of Food Science and Human Nutrition, School of Food and Nutritional Sciences, Agricultural University of Athens, 11855 Athens, Greece
| | - Harpal Randeva
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM), University Hospitals Coventry and Warwickshire NHS Trust, Coventry CV2 2DX, UK (H.R.)
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
- Institute for Cardiometabolic Medicine, University Hospitals Coventry and Warwickshire NHS Trust, Coventry CV2 2DX, UK
- Centre for Sport, Exercise and Life Sciences, Research Institute for Health & Wellbeing, Coventry University, Coventry CV1 5FB, UK
| | - Emmanouil Karteris
- College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge UB83PH, UK; (R.H.); (E.K.)
| | - Jayanta Chatterjee
- College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge UB83PH, UK; (R.H.); (E.K.)
- Academic Department of Gynaecological Oncology, Royal Surrey NHS Foundation Trust Hospital, Guildford GU2 7XX, UK
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Kamada Y, Umeda C, Mukai Y, Ohtsuka H, Otsubo Y, Yamashita A, Kosugi T. Structure-based engineering of Tor complexes reveals that two types of yeast TORC1 produce distinct phenotypes. J Cell Sci 2024; 137:jcs261625. [PMID: 38415789 PMCID: PMC10941655 DOI: 10.1242/jcs.261625] [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: 09/06/2023] [Accepted: 01/18/2024] [Indexed: 02/29/2024] Open
Abstract
Certain proteins assemble into diverse complex states, each having a distinct and unique function in the cell. Target of rapamycin (Tor) complex 1 (TORC1) plays a central role in signalling pathways that allow cells to respond to the environment, including nutritional status signalling. TORC1 is widely recognised for its association with various diseases. The budding yeast Saccharomyces cerevisiae has two types of TORC1, Tor1-containing TORC1 and Tor2-containing TORC1, which comprise different constituent proteins but are considered to have the same function. Here, we computationally modelled the relevant complex structures and then, based on the structures, rationally engineered a Tor2 mutant that could form Tor complex 2 (TORC2) but not TORC1, resulting in a redesign of the complex states. Functional analysis of the Tor2 mutant revealed that the two types of TORC1 induce different phenotypes, with changes observed in rapamycin, caffeine and pH dependencies of cell growth, as well as in replicative and chronological lifespan. These findings uncovered by a general approach with huge potential - model structure-based engineering - are expected to provide further insights into various fields such as molecular evolution and lifespan.
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Affiliation(s)
- Yoshiaki Kamada
- Interdisciplinary Research Unit, National Institute for Basic Biology (NIBB), National Institutes of Natural Sciences (NINS), Okazaki, Aichi, 444-8585, Japan
- Basic Biology Program, SOKENDAI (The Graduate University for Advanced Studies), Hayama, Kanagawa, 240-0193, Japan
| | - Chiharu Umeda
- Department of Frontier Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, 526-0829, Japan
| | - Yukio Mukai
- Department of Frontier Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, 526-0829, Japan
| | - Hokuto Ohtsuka
- Laboratory of Molecular Microbiology, Graduate School of Pharmaceutical Sciences, Nagoya University, Nagoya, Aichi, 464-8601, Japan
| | - Yoko Otsubo
- Interdisciplinary Research Unit, National Institute for Basic Biology (NIBB), National Institutes of Natural Sciences (NINS), Okazaki, Aichi, 444-8585, Japan
| | - Akira Yamashita
- Interdisciplinary Research Unit, National Institute for Basic Biology (NIBB), National Institutes of Natural Sciences (NINS), Okazaki, Aichi, 444-8585, Japan
| | - Takahiro Kosugi
- Research Center of Integrative Molecular Systems (CIMoS), Institute for Molecular Science (IMS), National Institutes of Natural Sciences (NINS), Okazaki, Aichi, 444-8585, Japan
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences (NINS), Okazaki, Aichi, 444-8585, Japan
- Molecular Science Program, SOKENDAI (The Graduate University for Advanced Studies), Hayama, Kanagawa, 240-0193, Japan
- Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan
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7
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Meinhold S, Zdanowicz R, Giese C, Glockshuber R. Dimerization of a 5-kDa domain defines the architecture of the 5-MDa gammaproteobacterial pyruvate dehydrogenase complex. SCIENCE ADVANCES 2024; 10:eadj6358. [PMID: 38324697 PMCID: PMC10849603 DOI: 10.1126/sciadv.adj6358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 01/11/2024] [Indexed: 02/09/2024]
Abstract
The Escherichia coli pyruvate dehydrogenase complex (PDHc) is a ~5 MDa assembly of the catalytic subunits pyruvate dehydrogenase (E1), dihydrolipoamide acetyltransferase (E2), and dihydrolipoamide dehydrogenase (E3). The PDHc core is a cubic complex of eight E2 homotrimers. Homodimers of the peripheral subunits E1 and E3 associate with the core by binding to the peripheral subunit binding domain (PSBD) of E2. Previous reports indicated that 12 E1 dimers and 6 E3 dimers bind to the 24-meric E2 core. Using an assembly arrested E2 homotrimer (E23), we show that two of the three PSBDs in the E23 dimerize, that each PSBD dimer cooperatively binds two E1 dimers, and that E3 dimers only bind to the unpaired PSBD in E23. This mechanism is preserved in wild-type PDHc, with an E1 dimer:E2 monomer:E3 dimer stoichiometry of 16:24:8. The conserved PSBD dimer interface indicates that PSBD dimerization is the previously unrecognized architectural determinant of gammaproteobacterial PDHc megacomplexes.
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Affiliation(s)
| | | | - Christoph Giese
- ETH Zürich, Institute of Molecular Biology and Biophysics, Otto-Stern-Weg 5, 8093 Zürich, Switzerland
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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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9
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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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10
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López-Perrote A, Serna M, Llorca O. Maturation and Assembly of mTOR Complexes by the HSP90-R2TP-TTT Chaperone System: Molecular Insights and Mechanisms. Subcell Biochem 2024; 104:459-483. [PMID: 38963496 DOI: 10.1007/978-3-031-58843-3_17] [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: 07/05/2024]
Abstract
The mechanistic target of rapamycin (mTOR) is a master regulator of cell growth and metabolism, integrating environmental signals to regulate anabolic and catabolic processes, regulating lipid synthesis, growth factor-induced cell proliferation, cell survival, and migration. These activities are performed as part of two distinct complexes, mTORC1 and mTORC2, each with specific roles. mTORC1 and mTORC2 are elaborated dimeric structures formed by the interaction of mTOR with specific partners. mTOR functions only as part of these large complexes, but their assembly and activation require a dedicated and sophisticated chaperone system. mTOR folding and assembly are temporarily separated with the TELO2-TTI1-TTI2 (TTT) complex assisting the cotranslational folding of mTOR into a native conformation. Matured mTOR is then transferred to the R2TP complex for assembly of active mTORC1 and mTORC2 complexes. R2TP works in concert with the HSP90 chaperone to promote the incorporation of additional subunits to mTOR and dimerization. This review summarizes our current knowledge on how the HSP90-R2TP-TTT chaperone system facilitates the maturation and assembly of active mTORC1 and mTORC2 complexes, discussing interactions, structures, and mechanisms.
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Affiliation(s)
- Andrés López-Perrote
- Spanish National Cancer Research Centre (CNIO), Structural Biology Programme, Melchor Fernández Almagro 3, Madrid, Spain.
| | - Marina Serna
- Spanish National Cancer Research Centre (CNIO), Structural Biology Programme, Melchor Fernández Almagro 3, Madrid, Spain
| | - Oscar Llorca
- Spanish National Cancer Research Centre (CNIO), Structural Biology Programme, Melchor Fernández Almagro 3, Madrid, Spain.
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11
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Lashgari NA, Roudsari NM, Shayan M, Eshraghi S, Momtaz S, Jamialahmadi T, Abdolghaffari AH, Sahebkar A. Spinal Muscular Atrophy Treatment: The MTOR Regulatory Intervention. Curr Med Chem 2024; 31:1512-1522. [PMID: 36788689 DOI: 10.2174/0929867330666230213114909] [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: 07/21/2022] [Revised: 11/29/2022] [Accepted: 12/29/2022] [Indexed: 02/16/2023]
Abstract
Spinal muscular atrophy (SMA) is a hereditary disorder affecting neurons and muscles, resulting in muscle weakness and atrophy. Most SMA cases are diagnosed during infancy or early childhood, the most common inherited cause of infant mortality without treatment. Still, SMA might appear at older ages with milder symptoms. SMA patients demonstrate progressive muscle waste, movement problems, tremors, dysphagia, bone and joint deformations, and breathing difficulties. The mammalian target of rapamycin (mTOR), the mechanistic target of rapamycin, is a member of the phosphatidylinositol 3-kinase-related kinase family of protein kinases encoded by the mTOR gene in humans. The mTOR phosphorylation, deregulation, and autophagy have shown dissimilarity amongst SMA cell types. Therefore, exploring the underlying molecular process in SMA therapy could provide novel insights and pave the way for finding new treatment options. This paper provides new insight into the possible modulatory effect of mTOR/ autophagy in SMA management.
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Affiliation(s)
- Naser-Aldin Lashgari
- Department of Toxicology & Pharmacology, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
- GI Pharmacology Interest Group (GPIG), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Nazanin Momeni Roudsari
- Department of Toxicology & Pharmacology, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
- GI Pharmacology Interest Group (GPIG), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Maryam Shayan
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Sadaf Eshraghi
- Department of Toxicology & Pharmacology, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Saeideh Momtaz
- GI Pharmacology Interest Group (GPIG), Universal Scientific Education and Research Network (USERN), Tehran, Iran
- Medicinal Plants Research Center, Institute of Medicinal Plants, ACECR, Karaj, Iran
- Toxicology and Diseases Group (TDG), Pharmaceutical Sciences Research Center (PSRC), The Institute of Pharmaceutical Sciences (TIPS), and Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Tannaz Jamialahmadi
- Surgical Oncology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Amir Hossein Abdolghaffari
- Department of Toxicology & Pharmacology, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
- GI Pharmacology Interest Group (GPIG), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Amirhossein Sahebkar
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
- School of Medicine, The University of Western Australia, Perth, Australia
- Department of Biotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
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12
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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: 25] [Impact Index Per Article: 25.0] [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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13
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Rivas VN, Kaplan JL, Kennedy SA, Fitzgerald S, Crofton AE, Farrell A, Grubb L, Jauregui CE, Grigorean G, Choi E, Harris SP, Stern JA. Multi-Omic, Histopathologic, and Clinicopathologic Effects of Once-Weekly Oral Rapamycin in a Naturally Occurring Feline Model of Hypertrophic Cardiomyopathy: A Pilot Study. Animals (Basel) 2023; 13:3184. [PMID: 37893908 PMCID: PMC10603660 DOI: 10.3390/ani13203184] [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: 08/10/2023] [Revised: 10/09/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) remains the single most common cardiomyopathy in cats, with a staggering prevalence as high as 15%. To date, little to no direct therapeutical intervention for HCM exists for veterinary patients. A previous study aimed to evaluate the effects of delayed-release (DR) rapamycin dosing in a client-owned population of subclinical, non-obstructive, HCM-affected cats and reported that the drug was well tolerated and resulted in beneficial LV remodeling. However, the precise effects of rapamycin in the hypertrophied myocardium remain unknown. Using a feline research colony with naturally occurring hereditary HCM (n = 9), we embarked on the first-ever pilot study to examine the tissue-, urine-, and plasma-level proteomic and tissue-level transcriptomic effects of an intermittent low dose (0.15 mg/kg) and high dose (0.30 mg/kg) of DR oral rapamycin once weekly. Rapamycin remained safe and well tolerated in cats receiving both doses for eight weeks. Following repeated weekly dosing, transcriptomic differences between the low- and high-dose groups support dose-responsive suppressive effects on myocardial hypertrophy and stimulatory effects on autophagy. Differences in the myocardial proteome between treated and control cats suggest potential anti-coagulant/-thrombotic, cellular remodeling, and metabolic effects of the drug. The results of this study closely recapitulate what is observed in the human literature, and the use of rapamycin in the clinical setting as the first therapeutic agent with disease-modifying effects on HCM remains promising. The results of this study establish the need for future validation efforts that investigate the fine-scale relationship between rapamycin treatment and the most compelling gene expression and protein abundance differences reported here.
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Affiliation(s)
- Victor N. Rivas
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
| | - Joanna L. Kaplan
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
| | | | | | - Amanda E. Crofton
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
| | | | | | - Carina E. Jauregui
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
| | - Gabriela Grigorean
- Proteomics Core Facility, University of California-Davis, Davis, CA 95616, USA
| | - Eunju Choi
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA;
| | - Samantha P. Harris
- Department of Physiology, College of Medicine-Tucson, University of Arizona, Tucson, AZ 85724, USA
| | - Joshua A. Stern
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
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14
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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: 93] [Impact Index Per Article: 93.0] [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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15
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Ezine E, Lebbe C, Dumaz N. Unmasking the tumourigenic role of SIN1/MAPKAP1 in the mTOR complex 2. Clin Transl Med 2023; 13:e1464. [PMID: 37877351 PMCID: PMC10599286 DOI: 10.1002/ctm2.1464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 10/09/2023] [Accepted: 10/16/2023] [Indexed: 10/26/2023] Open
Abstract
BACKGROUND Although the PI3K/AKT/mTOR pathway is one of the most altered pathways in human tumours, therapies targeting this pathway have shown numerous adverse effects due to positive feedback paradoxically activating upstream signaling nodes. The somewhat limited clinical efficacy of these inhibitors calls for the development of novel and more effective approaches for targeting the PI3K pathway for therapeutic benefit in cancer. MAIN BODY Recent studies have shown the central role of mTOR complex 2 (mTORC2) as a pro-tumourigenic factor of the PI3K/AKT/mTOR pathway in a number of cancers. SIN1/MAPKAP1 is a major partner of mTORC2, acting as a scaffold and responsible for the substrate specificity of the mTOR catalytic subunit. Its overexpression promotes the proliferation, invasion and metastasis of certain cancers whereas its inhibition decreases tumour growth in vitro and in vivo. It is also involved in epithelial-mesenchymal transition, stress response and lipogenesis. Moreover, the numerous interactions of SIN1 inside or outside mTORC2 connect it with other signaling pathways, which are often disrupted in human tumours such as Hippo, WNT, Notch and MAPK. CONCLUSION Therefore, SIN1's fundamental characteristics and numerous connexions with oncogenic pathways make it a particularly interesting therapeutic target. This review is an opportunity to highlight the tumourigenic role of SIN1 across many solid cancers and demonstrates the importance of targeting SIN1 with a specific therapy.
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Affiliation(s)
- Emilien Ezine
- INSERMU976Team 1Human Immunology Pathophysiology & Immunotherapy (HIPI)ParisFrance
- Département de DermatologieHôpital Saint LouisAP‐HPParisFrance
| | - Céleste Lebbe
- INSERMU976Team 1Human Immunology Pathophysiology & Immunotherapy (HIPI)ParisFrance
- Département de DermatologieHôpital Saint LouisAP‐HPParisFrance
- Université Paris CitéInstitut de Recherche Saint Louis (IRSL)ParisFrance
| | - Nicolas Dumaz
- INSERMU976Team 1Human Immunology Pathophysiology & Immunotherapy (HIPI)ParisFrance
- Université Paris CitéInstitut de Recherche Saint Louis (IRSL)ParisFrance
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16
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Linde-Garelli KY, Rogala KB. Structural mechanisms of the mTOR pathway. Curr Opin Struct Biol 2023; 82:102663. [PMID: 37572585 DOI: 10.1016/j.sbi.2023.102663] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 07/01/2023] [Accepted: 07/07/2023] [Indexed: 08/14/2023]
Abstract
The mTOR signaling pathway is essential for regulating cell growth and mammalian metabolism. The mTOR kinase forms two complexes, mTORC1 and mTORC2, which respond to external stimuli and regulate differential downstream targets. Cellular membrane-associated translocation mediates function and assembly of the mTOR complexes, and recent structural studies have begun uncovering the molecular basis by which the mTOR pathway (1) regulates signaling inputs, (2) recruits substrates, (3) localizes to biological membranes, and (4) becomes activated. Moreover, indications of dysregulated mTOR signaling are implicated in a wide range of diseases and an increasingly comprehensive understanding of structural mechanisms is driving novel translational development.
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Affiliation(s)
- Karen Y Linde-Garelli
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Kacper B Rogala
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA.
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17
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Konopka AR, Lamming DW. Blazing a trail for the clinical use of rapamycin as a geroprotecTOR. GeroScience 2023; 45:2769-2783. [PMID: 37801202 PMCID: PMC10643772 DOI: 10.1007/s11357-023-00935-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: 06/23/2023] [Accepted: 09/04/2023] [Indexed: 10/07/2023] Open
Abstract
Treatment with rapamycin, an inhibitor of the mechanistic Target Of Rapamycin Complex One (mTORC1) protein kinase, has been repeatedly demonstrated to extend lifespan and prevent or delay age-related diseases in diverse model systems. Concerns over the risk of potentially serious side effects in humans, including immunosuppression and metabolic disruptions, have cautiously limited the translation of rapamycin and its analogs as a treatment for aging associated conditions. During the last decade, we and others have developed a working model that suggests that while inhibition of mTORC1 promotes healthy aging, many of the negative side effects of rapamycin are associated with "off-target" inhibition of a second mTOR complex, mTORC2. Differences in the kinetics and molecular mechanisms by which rapamycin inhibits mTORC1 and mTORC2 suggest that a therapeutic window for rapamycin could be exploited using intermittent dosing schedules or alternative rapalogs that may enable more selective inhibition of mTORC1. However, the optimal dosing schedules and the long-term efficacy of such interventions in humans are unknown. Here, we highlight ongoing or upcoming clinical trials that will address outstanding questions regarding the safety, pharmacokinetics, pharmacodynamics, and efficacy of rapamycin and rapalogs on several clinically oriented outcomes. Results from these early phase studies will help guide the design of phase 3 clinical trials to determine whether rapamycin can be used safely to inhibit mTORC1 for the treatment and prevention of age-related diseases in humans.
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Affiliation(s)
- Adam R Konopka
- Division of Geriatrics, Department of Medicine, University of Wisconsin-Madison, Madison, WI, 53705, USA.
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705, USA.
- Division of Geriatrics and Gerontology, Department of Medicine, Geriatric Research Education and Clinical Center (GRECC), William S. Middleton Memorial Veterans Hospital, University of Wisconsin-Madison, 2500 Overlook Terrace, Madison, WI, 53705, USA.
| | - Dudley W Lamming
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705, USA
- Division of Endocrinology, Department of Medicine, University of Wisconsin-Madison, Madison, WI, 53705, USA
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18
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Chen Y, Xu Z, Sun H, Ouyang X, Han Y, Yu H, Wu N, Xie Y, Su B. Regulation of CD8 + T memory and exhaustion by the mTOR signals. Cell Mol Immunol 2023; 20:1023-1039. [PMID: 37582972 PMCID: PMC10468538 DOI: 10.1038/s41423-023-01064-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 07/02/2023] [Indexed: 08/17/2023] Open
Abstract
CD8+ T cells are the key executioners of the adaptive immune arm, which mediates antitumor and antiviral immunity. Naïve CD8+ T cells develop in the thymus and are quickly activated in the periphery after encountering a cognate antigen, which induces these cells to proliferate and differentiate into effector cells that fight the initial infection. Simultaneously, a fraction of these cells become long-lived memory CD8+ T cells that combat future infections. Notably, the generation and maintenance of memory cells is profoundly affected by various in vivo conditions, such as the mode of primary activation (e.g., acute vs. chronic immunization) or fluctuations in host metabolic, inflammatory, or aging factors. Therefore, many T cells may be lost or become exhausted and no longer functional. Complicated intracellular signaling pathways, transcription factors, epigenetic modifications, and metabolic processes are involved in this process. Therefore, understanding the cellular and molecular basis for the generation and fate of memory and exhausted CD8+ cells is central for harnessing cellular immunity. In this review, we focus on mammalian target of rapamycin (mTOR), particularly signaling mediated by mTOR complex (mTORC) 2 in memory and exhausted CD8+ T cells at the molecular level.
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Affiliation(s)
- Yao Chen
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, and The Ministry of Education Key Laboratory of Cell Death and Differentiation, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Ziyang Xu
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, and The Ministry of Education Key Laboratory of Cell Death and Differentiation, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Hongxiang Sun
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, and The Ministry of Education Key Laboratory of Cell Death and Differentiation, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Xinxing Ouyang
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, and The Ministry of Education Key Laboratory of Cell Death and Differentiation, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Department of Tumor Biology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Yuheng Han
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, and The Ministry of Education Key Laboratory of Cell Death and Differentiation, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Haihui Yu
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, and The Ministry of Education Key Laboratory of Cell Death and Differentiation, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Ningbo Wu
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, and The Ministry of Education Key Laboratory of Cell Death and Differentiation, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Yiting Xie
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, and The Ministry of Education Key Laboratory of Cell Death and Differentiation, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Bing Su
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, and The Ministry of Education Key Laboratory of Cell Death and Differentiation, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
- Department of Tumor Biology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
- Center for Immune-Related Diseases at Shanghai Institute of Immunology, Department of Gastroenterology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
- Shanghai Jiao Tong University School of Medicine-Yale Institute for Immune Metabolism, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
- Key Laboratory of Molecular Radiation Oncology of Hunan Province, Xiangya Hospital, Central South University, Changsha, China.
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19
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Melanis K, Stefanou MI, Themistoklis KM, Papasilekas T. mTOR pathway - a potential therapeutic target in stroke. Ther Adv Neurol Disord 2023; 16:17562864231187770. [PMID: 37576547 PMCID: PMC10413897 DOI: 10.1177/17562864231187770] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 06/27/2023] [Indexed: 08/15/2023] Open
Abstract
Stroke is ranked as the second leading cause of death worldwide and a major cause of long-term disability. A potential therapeutic target that could offer favorable outcomes in stroke is the mammalian target of rapamycin (mTOR) pathway. mTOR is a serine/threonine kinase that composes two protein complexes, mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2), and is regulated by other proteins such as the tuberous sclerosis complex. Through a significant number of signaling pathways, the mTOR pathway can modulate the processes of post-ischemic inflammation and autophagy, both of which play an integral part in the pathophysiological cascade of stroke. Promoting or inhibiting such processes under ischemic conditions can lead to apoptosis or instead sustained viability of neurons. The purpose of this review is to examine the pathophysiological role of mTOR in acute ischemic stroke, while highlighting promising neuroprotective agents such as hamartin for therapeutic modulation of this pathway. The therapeutic potential of mTOR is also discussed, with emphasis on implicated molecules and pathway steps that warrant further elucidation in order for their neuroprotective properties to be efficiently tested in future clinical trials.
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Affiliation(s)
- Konstantinos Melanis
- Second Department of Neurology, School of Medicine and ‘Attikon’ University Hospital, National and Kapodistrian University of Athens, Rimini 1 Chaidari, Athens 12462, Greece
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Maria-Ioanna Stefanou
- Second Department of Neurology, School of Medicine and ‘Attikon’ University Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Konstantinos M. Themistoklis
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- Department of Neurosurgery, ‘Korgialenio, Benakio, H.R.C’. General Hospital of Athens, Athens, Greece
| | - Themistoklis Papasilekas
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- Department of Neurosurgery, ‘Korgialenio, Benakio, H.R.C’. General Hospital of Athens, Athens, Greece
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20
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El-Senduny FF, Elgazar AA, Alwasify HA, Abed A, Foda M, Abouzeid S, Lewerenz L, Selmar D, Badria F. Bio-evaluation of Untapped Alkaloids from Vinca minor Enriched by Methyl-jasmonate-induced Stress: an Integrated Approach. PLANTA MEDICA 2023; 89:964-978. [PMID: 36940927 DOI: 10.1055/a-2058-3863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The low amount of metabolites isolated from natural products is one of the challenges preventing their biological evaluation. The modulation of biosynthetic pathways by stimulating stress-induced responses in plants was proven to be a valuable tool for diversification of already known natural products. Recently, we reported the dramatic effect of methyl jasmonate (MeJA) on Vinca minor alkaloids distribution. In this study, three compounds identified as 9-methoxyvincamine, minovincinine, and minovincine are successfully isolated in good yield and subjected to several bioassays based on a network pharmacology study. The extracts and isolated compounds show weak to moderate antimicrobial and cytotoxic activities. Also, they are found to significantly promote wound healing in scratch assay, and transforming growth factor-β (TGF-β) modulation is suggested to be the potential pathway based on bioinformatic analysis. Hence, Western blotting is used to assess the expression of several markers related to this pathway and wound healing. The extracts and isolated compounds are able to increase the expression of Smad3 and Phosphatidylinositol-3-kinase (PI3K), while downregulating the levels of cyclin D1 and the mammalian target of rapamycin (mTOR) except for minovincine, which increases the mTOR expression, inferring that it might act through a different mechanism. Molecular docking is used to give insights on the ability of isolated compounds to bind with different active sites in mTOR. Collectively, the integrated phytochemical, in silico, and molecular biology approach reveal that V. minor and its metabolite could be repurposed for the management of dermatological disorders where these markers are dysregulated, which opens the gate to develop new therapeutics in the future.
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Affiliation(s)
- Fardous F El-Senduny
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt
- Department of Pathology & Laboratory Medicine, Sylvester Comprehensive Cancer Center, Miami, FL, United States
| | - Abdullah A Elgazar
- Department of Pharmacognosy, Faculty of Pharmacy, Kafrelsheikh University, Kafrelsheikh, Egypt
| | - Heba Allah Alwasify
- Zoology Department, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Alaa Abed
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Mohamed Foda
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Sara Abouzeid
- Pharmacognosy Department, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
- Institute for Plant Biology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Laura Lewerenz
- Institute for Plant Biology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Dirk Selmar
- Institute for Plant Biology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Farid Badria
- Pharmacognosy Department, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
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21
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Gao Y, Tian T. mTOR Signaling Pathway and Gut Microbiota in Various Disorders: Mechanisms and Potential Drugs in Pharmacotherapy. Int J Mol Sci 2023; 24:11811. [PMID: 37511569 PMCID: PMC10380532 DOI: 10.3390/ijms241411811] [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: 06/12/2023] [Revised: 07/15/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
The mammalian or mechanistic target of rapamycin (mTOR) integrates multiple intracellular and extracellular upstream signals involved in the regulation of anabolic and catabolic processes in cells and plays a key regulatory role in cell growth and metabolism. The activation of the mTOR signaling pathway has been reported to be associated with a wide range of human diseases. A growing number of in vivo and in vitro studies have demonstrated that gut microbes and their complex metabolites can regulate host metabolic and immune responses through the mTOR pathway and result in disorders of host physiological functions. In this review, we summarize the regulatory mechanisms of gut microbes and mTOR in different diseases and discuss the crosstalk between gut microbes and their metabolites and mTOR in disorders in the gastrointestinal tract, liver, heart, and other organs. We also discuss the promising application of multiple potential drugs that can adjust the gut microbiota and mTOR signaling pathways. Despite the limited findings between gut microbes and mTOR, elucidating their relationship may provide new clues for the prevention and treatment of various diseases.
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Affiliation(s)
- Yuan Gao
- College of Life Science and Bioengineering, Beijing Jiaotong University, Beijing 100044, China
| | - Tian Tian
- College of Life Science and Bioengineering, Beijing Jiaotong University, Beijing 100044, China
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22
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Li X, Chen K, Wang Z, Li J, Wang X, Xie C, Tong J, Shen Y. The mTOR signalling in corneal diseases: A recent update. Biochem Pharmacol 2023; 213:115620. [PMID: 37217140 DOI: 10.1016/j.bcp.2023.115620] [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: 03/23/2023] [Revised: 05/16/2023] [Accepted: 05/16/2023] [Indexed: 05/24/2023]
Abstract
Corneal diseases affect 4.2 million people worldwide and are a leading cause of vision impairment and blindness. Current treatments for corneal diseases, such as antibiotics, steroids, and surgical interventions, have numerous disadvantages and challenges. Thus, there is an urgent need for more effective therapies. Although the pathogenesis of corneal diseases is not fully understood, it is known that injury caused by various stresses and postinjury healing, such as epithelial renewal, inflammation, stromal fibrosis, and neovascularization, are highly involved. Mammalian target of rapamycin (mTOR) is a key regulator of cell growth, metabolism, and the immune response. Recent studies have revealed that activation of mTOR signalling extensively contributes to the pathogenesis of various corneal diseases, and inhibition of mTOR with rapamycin achieves promising outcomes, supporting the potential of mTOR as a therapeutic target. In this review, we detail the function of mTOR in corneal diseases and how these characteristics contribute to disease treatment using mTOR-targeted drugs.
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Affiliation(s)
- Xiang Li
- Department of Ophthalmology, the First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Kuangqi Chen
- Department of Ophthalmology, the First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Zixi Wang
- Bone Marrow Transplantation Center, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jiayuan Li
- Department of Ophthalmology, the First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Xiawei Wang
- Department of Ophthalmology, the First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Chen Xie
- Department of Ophthalmology, the First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang Province, China.
| | - Jianping Tong
- Department of Ophthalmology, the First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang Province, China.
| | - Ye Shen
- Department of Ophthalmology, the First Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang Province, China.
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Mannick JB, Lamming DW. Targeting the biology of aging with mTOR inhibitors. NATURE AGING 2023; 3:642-660. [PMID: 37142830 PMCID: PMC10330278 DOI: 10.1038/s43587-023-00416-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 04/07/2023] [Indexed: 05/06/2023]
Abstract
Inhibition of the protein kinase mechanistic target of rapamycin (mTOR) with the Food and Drug Administration (FDA)-approved therapeutic rapamycin promotes health and longevity in diverse model organisms. More recently, specific inhibition of mTORC1 to treat aging-related conditions has become the goal of basic and translational scientists, clinicians and biotechnology companies. Here, we review the effects of rapamycin on the longevity and survival of both wild-type mice and mouse models of human diseases. We discuss recent clinical trials that have explored whether existing mTOR inhibitors can safely prevent, delay or treat multiple diseases of aging. Finally, we discuss how new molecules may provide routes to the safer and more selective inhibition of mTOR complex 1 (mTORC1) in the decade ahead. We conclude by discussing what work remains to be done and the questions that will need to be addressed to make mTOR inhibitors part of the standard of care for diseases of aging.
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Affiliation(s)
| | - Dudley W Lamming
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.
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24
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Tu M, Wei T, Jia Y, Wang Y, Wu J. Molecular mechanisms of alveolar epithelial cell senescence and idiopathic pulmonary fibrosis: a narrative review. J Thorac Dis 2023; 15:186-203. [PMID: 36794134 PMCID: PMC9922607 DOI: 10.21037/jtd-22-886] [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: 06/25/2022] [Accepted: 11/25/2022] [Indexed: 12/29/2022]
Abstract
Background and Objective Idiopathic pulmonary fibrosis (IPF) is a chronic progressive interstitial pneumonia of unknown etiology. An increasing number of studies have reported that the incidence of IPF increases with age. Simultaneously, the number of senescent cells increased in IPF. Epithelial cell senescence, an important component of epithelial cell dysfunction, plays a key role in IPF pathogenesis. This article summarizes the molecular mechanisms associated with alveolar epithelial cell senescence and recent advances in the applications of drugs targeting pulmonary epithelial cell senescence to explore novel therapeutic approaches for the treatment of pulmonary fibrosis. Methods All literature published in English on PubMed, Web of Science, and Google Scholar were electronically searched online using the following keyword combinations: aging, alveolar epithelial cell, cell senescence, idiopathic pulmonary fibrosis, WNT/β-catenin, phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt), mammalian target of rapamycin (mTOR), and nuclear factor kappa B (NF-κB). Key Content and Findings We focused on signaling pathways associated with alveolar epithelial cell senescence in IPF, including WNT/β-catenin, PI3K/Akt, NF-κB, and mTOR signaling pathways. Some of these signaling pathways are involved in alveolar epithelial cell senescence by affecting cell cycle arrest and secretion of senescence-associated secretory phenotype-associated markers. We also found that changes in lipid metabolism in alveolar epithelial cells can be induced by mitochondrial dysfunction, both of which contribute to cellular senescence and development of IPF. Conclusions Decreasing senescent alveolar epithelial cells may be a promising strategy for the treatment of IPF. Therefore, further investigations into new treatments of IPF by applying inhibitors of relevant signaling pathways, as well as senolytic drugs, are warranted.
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Affiliation(s)
- Mingjin Tu
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Guangdong Medical University, Guangdong Medical University, Zhanjiang, China;,Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China;,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China;,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China
| | - Ting Wei
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Guangdong Medical University, Guangdong Medical University, Zhanjiang, China;,Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China;,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China;,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China
| | - Yufang Jia
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Guangdong Medical University, Guangdong Medical University, Zhanjiang, China;,Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China;,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China;,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China
| | - Yajun Wang
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Guangdong Medical University, Guangdong Medical University, Zhanjiang, China;,Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China;,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China;,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China;,Shunde Women and Children’s Hospital, Guangdong Medical University, Foshan, China
| | - Jun Wu
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Guangdong Medical University, Guangdong Medical University, Zhanjiang, China;,Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China;,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China;,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China
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25
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N,N'-Diarylurea Derivatives (CTPPU) Inhibited NSCLC Cell Growth and Induced Cell Cycle Arrest through Akt/GSK-3β/c-Myc Signaling Pathway. Int J Mol Sci 2023; 24:ijms24021357. [PMID: 36674871 PMCID: PMC9866857 DOI: 10.3390/ijms24021357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 01/13/2023] Open
Abstract
Lung cancer is one of the most common malignancies worldwide. Non-small-cell lung cancer (NSCLC) accounts for more than 80% of lung cancers, shows chemotherapy resistance, metastasis, and relapse. The phosphatidylinositol-3 kinase (PI3K)/Akt pathway has been implicated in the carcinogenesis and disease progression of NSCLC, suggesting that it may be a promising therapeutic target for cancer therapy. Although phenylurea derivatives have been reported as potent multiple kinase inhibitors, novel unsymmetrical N,N'-diarylurea derivatives targeting the PI3K/Akt pathway in NSCLC cells remain unknown. METHODS N,N'-substituted phenylurea derivatives CTPPU and CT-(4-OH)-PU were investigated for their anticancer proliferative activity against three NSCLC cell lines (H460, A549, and H292) by 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide, colony formation, Hoechst33342/PI staining assays, and apoptosis analysis. The protein expressions of Akt pathway-related proteins in response to CTPPU or CT-(4-OH)-PU were detected by Western blot analysis. The Kyoto Encyclopedia of Genes and Genomes mapper was used to identify the possible signaling pathways in NSCLC treated with CTPPU. The cell cycle was analyzed by flow cytometry. Molecular docking was used to investigate the possible binding interaction of CTPPU with Akt, the mammalian target of rapamycin complex 2 (mTORC2), and PI3Ks. Immunofluorescence and Western blot analysis were used to validate our prediction. RESULTS The cytotoxicity of CTPPU was two-fold higher than that of CT-(4-OH)-PU for all NSCLC cell lines. Similarly, the non-cytotoxic concentration of CTPPU (25 µM) dramatically inhibited the colony formation of NSCLC cells, whereas its relative analog CT-(4-OH)-PU had no effect. Protein analysis revealed that Akt and its downstream effectors, namely, phosphorylated glycogen synthase kinase (GSK)-3β (Ser9), β-catenin, and c-Myc, were reduced in response to CTPPU treatment, which suggested the targeting of Akt-dependent pathway, whereas CT-(4-OH)-PU had no effect on such cell growth regulatory signals. CTPPU induced G1/S cell cycle arrest in lung cancer cells. Immunofluorescence revealed that CTPPU decreased p-Akt and total Akt protein levels, which implied the effect of the compound on protein activity and stability. Next, we utilized in silico molecular docking analysis to reveal the potential molecular targets of CTPPU, and the results showed that the compound could specifically bind to the allosteric pocket of Akt and three sites of mTORC2 (catalytic site, A-site, and I-site), with a binding affinity greater than that of reference compounds. The compound cannot bind to PI3K, an upstream regulator of the Akt pathway. The effect of CTPPU on PI3K and Akt was confirmed. This finding indicated that the compound could decrease p-Akt but caused no effect on p-PI3K. CONCLUSIONS The results indicate that CTPPU significantly inhibits NSCLC cell proliferation by inducing G1/S cell cycle arrest via the Akt/GSK-3β/c-Myc signaling pathway. Molecular docking revealed that CTPPU could interact with Akt and mTORC2 molecules with a high binding affinity. These data indicate that CTPPU is a potential novel alternative therapeutic approach for NSCLC.
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Stary D, Nepovimova E, Kuca K, Bajda M. Searching for new mTOR kinase inhibitors: Analysis of binding sites and validation of docking protocols. Chem Biol Drug Des 2023; 101:103-119. [PMID: 35945665 DOI: 10.1111/cbdd.14126] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/18/2022] [Accepted: 07/30/2022] [Indexed: 12/15/2022]
Abstract
The mammalian target of rapamycin (mTOR) is an important biological target for development of novel anticancer drugs and potential antiageing agents. Therefore, many scientific groups search for mTOR kinase inhibitors. Herein, we present structure-based approach which could be helpful in the studies on new bioactive compounds. Method validation was preceded by structural analysis of ATP catalytic cleft and FRB domain. In silico studies allowed us to point crucial amino acid residues for ligand binding and develop optimal docking protocols. The presented methodology could be applied for design and development of potential mTOR kinase inhibitors.
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Affiliation(s)
- Dorota Stary
- Department of Physicochemical Drug Analysis, Faculty of Pharmacy, Jagiellonian University Medical College, Cracow, Poland.,Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic.,Doctoral School of Medical and Health Sciences, Jagiellonian University Medical College, Cracow, Poland
| | - Eugenie Nepovimova
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Kamil Kuca
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Marek Bajda
- Department of Physicochemical Drug Analysis, Faculty of Pharmacy, Jagiellonian University Medical College, Cracow, Poland.,Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
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27
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Burnett GL, Yang YC, Aggen JB, Pitzen J, Gliedt MK, Semko CM, Marquez A, Evans JW, Wang G, Won WS, Tomlinson ACA, Kiss G, Tzitzilonis C, Thottumkara AP, Cregg J, Mellem KT, Choi JS, Lee JC, Zhao Y, Lee BJ, Meyerowitz JG, Knox JE, Jiang J, Wang Z, Wildes D, Wang Z, Singh M, Smith JA, Gill AL. Discovery of RMC-5552, a Selective Bi-Steric Inhibitor of mTORC1, for the Treatment of mTORC1-Activated Tumors. J Med Chem 2022; 66:149-169. [PMID: 36533617 PMCID: PMC9841523 DOI: 10.1021/acs.jmedchem.2c01658] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Hyperactivation of mTOR kinase by mutations in the PI3K/mTOR pathway or by crosstalk with other mutant cancer drivers, such as RAS, is a feature of many tumors. Multiple allosteric inhibitors of mTORC1 and orthosteric dual inhibitors of mTORC1 and mTORC2 have been developed as anticancer drugs, but their clinical utility has been limited. To address these limitations, we have developed a novel class of "bi-steric inhibitors" that interact with both the orthosteric and the allosteric binding sites in order to deepen the inhibition of mTORC1 while also preserving selectivity for mTORC1 over mTORC2. In this report, we describe the discovery and preclinical profile of the development candidate RMC-5552 and the in vivo preclinical tool compound RMC-6272. We also present evidence that selective inhibition of mTORC1 in combination with covalent inhibition of KRASG12C shows increased antitumor activity in a preclinical model of KRASG12C mutant NSCLC that exhibits resistance to KRASG12C inhibitor monotherapy.
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Mammalian Target of Rapamycin (mTOR) Signaling at the Crossroad of Muscle Fiber Fate in Sarcopenia. Int J Mol Sci 2022; 23:ijms232213823. [PMID: 36430301 PMCID: PMC9696247 DOI: 10.3390/ijms232213823] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/02/2022] [Accepted: 11/08/2022] [Indexed: 11/12/2022] Open
Abstract
The mammalian target of rapamycin (mTOR) is a major regulator of skeletal myocyte viability. The signaling pathways triggered by mTOR vary according to the type of endogenous and exogenous factors (e.g., redox balance, nutrient availability, physical activity) as well as organismal age. Here, we provide an overview of mTOR signaling in skeletal muscle, with a special focus on the role played by mTOR in the development of sarcopenia. Intervention strategies targeting mTOR in sarcopenia (e.g., supplementation of plant extracts, hormones, inorganic ions, calorie restriction, and exercise) have also been discussed.
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Pudewell S, Lissy J, Nakhaeizadeh H, Mosaddeghzadeh N, Nakhaei-Rad S, Dvorsky R, Ahmadian MR. New mechanistic insights into the RAS-SIN1 interaction at the membrane. Front Cell Dev Biol 2022; 10:987754. [PMID: 36274845 PMCID: PMC9583166 DOI: 10.3389/fcell.2022.987754] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Stress-activated MAP kinase-interacting protein 1 (SIN1) is a central member of the mTORC2 complex that contains an N-terminal domain (NTD), a conserved region in the middle (CRIM), a RAS-binding domain (RBD), and a pleckstrin homology domain. Recent studies provided valuable structural and functional insights into the interactions of SIN1 and the RAS-binding domain of RAS proteins. However, the mechanism for a reciprocal interaction of the RBD-PH tandem with RAS proteins and the membrane as an upstream event to spatiotemporal mTORC2 regulation is not clear. The biochemical assays in this study led to the following results: 1) all classical RAS paralogs, including HRAS, KRAS4A, KRAS4B, and NRAS, can bind to SIN1-RBD in biophysical and SIN1 full length (FL) in cell biology experiments; 2) the SIN1-PH domain modulates interactions with various types of membrane phosphoinositides and constantly maintains a pool of SIN1 at the membrane; and 3) a KRAS4A-dependent decrease in membrane binding of the SIN1-RBD-PH tandem was observed, suggesting for the first time a mechanistic influence of KRAS4A on SIN1 membrane association. Our study strengthens the current mechanistic understanding of SIN1-RAS interaction and suggests membrane interaction as a key event in the control of mTORC2-dependent and mTORC2-independent SIN1 function.
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Affiliation(s)
- Silke Pudewell
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Jana Lissy
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Hossein Nakhaeizadeh
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Niloufar Mosaddeghzadeh
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Saeideh Nakhaei-Rad
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Stem Cell Biology and Regenerative Medicine Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Center for Interdisciplinary Biosciences, P. J. Šafárik University, Košice, Slovakia
| | - Mohammad R. Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- *Correspondence: Mohammad R. Ahmadian,
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30
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Thorner J. TOR complex 2 is a master regulator of plasma membrane homeostasis. Biochem J 2022; 479:1917-1940. [PMID: 36149412 PMCID: PMC9555796 DOI: 10.1042/bcj20220388] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 11/17/2022]
Abstract
As first demonstrated in budding yeast (Saccharomyces cerevisiae), all eukaryotic cells contain two, distinct multi-component protein kinase complexes that each harbor the TOR (Target Of Rapamycin) polypeptide as the catalytic subunit. These ensembles, dubbed TORC1 and TORC2, function as universal, centrally important sensors, integrators, and controllers of eukaryotic cell growth and homeostasis. TORC1, activated on the cytosolic surface of the lysosome (or, in yeast, on the cytosolic surface of the vacuole), has emerged as a primary nutrient sensor that promotes cellular biosynthesis and suppresses autophagy. TORC2, located primarily at the plasma membrane, plays a major role in maintaining the proper levels and bilayer distribution of all plasma membrane components (sphingolipids, glycerophospholipids, sterols, and integral membrane proteins). This article surveys what we have learned about signaling via the TORC2 complex, largely through studies conducted in S. cerevisiae. In this yeast, conditions that challenge plasma membrane integrity can, depending on the nature of the stress, stimulate or inhibit TORC2, resulting in, respectively, up-regulation or down-regulation of the phosphorylation and thus the activity of its essential downstream effector the AGC family protein kinase Ypk1. Through the ensuing effect on the efficiency with which Ypk1 phosphorylates multiple substrates that control diverse processes, membrane homeostasis is maintained. Thus, the major focus here is on TORC2, Ypk1, and the multifarious targets of Ypk1 and how the functions of these substrates are regulated by their Ypk1-mediated phosphorylation, with emphasis on recent advances in our understanding of these processes.
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Affiliation(s)
- Jeremy Thorner
- Division of Biochemistry, Biophysics and Structural Biology, Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720-3202, U.S.A
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31
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Petsri K, Thongsom S, Racha S, Chamni S, Jindapol S, Kaekratoke N, Zou H, Chanvorachote P. Novel mechanism of napabucasin, a naturally derived furanonaphthoquinone: apoptosis and autophagy induction in lung cancer cells through direct targeting on Akt/mTOR proteins. BMC Complement Med Ther 2022; 22:250. [PMID: 36180880 PMCID: PMC9524025 DOI: 10.1186/s12906-022-03727-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 09/15/2022] [Indexed: 11/22/2022] Open
Abstract
Background Akt and mTOR are aberrantly activated in cancers and targeting these proteins are interesting for cancer drug discovery. Napabucasin (NB), a phytochemical compound, has been reported as potential anti-cancer agent, however, Akt and mTOR targeting mechanisms remain unclear. Method Apoptosis induction was investigated by Hoechst 33342/PI double staining and annexin V/PI staining with flowcytometry. Autophagy was evaluated by monodansylcadaverine staining and Western blot analysis. Binding affinity of NB and essential signaling proteins (PI3K, Akt, and mTOR) was investigated using molecular docking and confirmed by Western blot analysis. Result A structure modification from changing methyl moiety of acetyl group of NB to hydroxyl moiety of carboxyl group of NB derivative (napabucasin-acid or NB-acid) greatly affected the compound activities. NB showed more potent anti-cancer activity. NB reduced cell viability with an approximately 20 times lower IC50 and inhibited the colony formation capacity much more than NB-acid treated cells. NB induced cell apoptosis, which was accompanied by decrease Bcl‑2 and Mcl-1 and clevage of PARP, while NB-acid show lesser effect on Mcl-1. NB was found to strongly induce autophagy indicated by acidic vesicle staining and the LC3B conversion. Interestingly, computational molecular docking analysis further demonstrated that NB directly bound to Akt and mTOR (complex 1 and 2) proteins at their critical sites indicating that NB targets the upstream regulators of apoptosis and autophagy. The docking results were confirmed by decrease of p-Akt/Akt, p-mTOR/mTOR, and c-Myc a downstream target of Akt protein levels. Conclusion Results show for the first time that NB exerts an anti-cancer activity through the direct interaction to Akt and mTOR proteins. The methyl moiety of acetyl group of NB is required for its potent anti-cancer activities. These data encourage further development of NB compounds for Akt and mTOR driven cancers. Supplementary Information The online version contains supplementary material available at 10.1186/s12906-022-03727-6.
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32
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Yazgili AS, Ebstein F, Meiners S. The Proteasome Activator PA200/PSME4: An Emerging New Player in Health and Disease. Biomolecules 2022; 12:1150. [PMID: 36009043 PMCID: PMC9406137 DOI: 10.3390/biom12081150] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 11/24/2022] Open
Abstract
Proteasomes comprise a family of proteasomal complexes essential for maintaining protein homeostasis. Accordingly, proteasomes represent promising therapeutic targets in multiple human diseases. Several proteasome inhibitors are approved for treating hematological cancers. However, their side effects impede their efficacy and broader therapeutic applications. Therefore, understanding the biology of the different proteasome complexes present in the cell is crucial for developing tailor-made inhibitors against specific proteasome complexes. Here, we will discuss the structure, biology, and function of the alternative Proteasome Activator 200 (PA200), also known as PSME4, and summarize the current evidence for its dysregulation in different human diseases. We hereby aim to stimulate research on this enigmatic proteasome regulator that has the potential to serve as a therapeutic target in cancer.
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Affiliation(s)
- Ayse Seda Yazgili
- Comprehensive Pneumology Center (CPC), Helmholtz Center Munich, Max-Lebsche Platz 31, 81377 Munich, Germany
| | - Frédéric Ebstein
- Institut für Medizinische Biochemie und Molekularbiologie (IMBM), Universitätsmedizin Greifswald, Ferdinand-Sauerbruch-Straße, Klinikum DZ/7, 17475 Greifswald, Germany
| | - Silke Meiners
- Research Center Borstel/Leibniz Lung Center, Parkallee 1-40, 23845 Borstel, Germany
- Airway Research Center North (ARCN), German Center for Lung Research (DZL), 23845 Sülfeld, Germany
- Institute of Experimental Medicine, Christian-Albrechts University Kiel, 24118 Kiel, Germany
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Luciano AK, Korobkina E, Lyons SP, Haley JA, Fluharty S, Jung SM, Kettenbach AN, Guertin DA. Proximity labeling of endogenous RICTOR identifies mTOR Complex 2 regulation by ADP ribosylation factor ARF1. J Biol Chem 2022; 298:102379. [PMID: 35973513 PMCID: PMC9513271 DOI: 10.1016/j.jbc.2022.102379] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 07/22/2022] [Accepted: 08/09/2022] [Indexed: 01/08/2023] Open
Abstract
Mechanistic target of rapamycin (mTOR) complex 2 (mTORC2) regulates metabolism, cell proliferation, and cell survival. mTORC2 activity is stimulated by growth factors, and it phosphorylates the hydrophobic motif site of the AGC kinases AKT, SGK, and PKC. However, the proteins that interact with mTORC2 to control its activity and localization remain poorly defined. To identify mTORC2-interacting proteins in living cells, we tagged endogenous RICTOR, an essential mTORC2 subunit, with the modified BirA biotin ligase BioID2 and performed live-cell proximity labeling. We identified 215 RICTOR-proximal proteins, including proteins with known mTORC2 pathway interactions, and 135 proteins (63%) not previously linked to mTORC2 signaling, including nuclear and cytoplasmic proteins. Our imaging and cell fractionation experiments suggest nearly 30% of RICTOR is in the nucleus, hinting at potential nuclear functions. We also identified 29 interactors containing RICTOR-dependent, insulin-stimulated phosphorylation sites, thus providing insight into mTORC2-dependent insulin signaling dynamics. Finally, we identify the endogenous ADP ribosylation factor 1 (ARF1) GTPase as an mTORC2-interacting protein. Through gain-of-function and loss-of-function studies, we provide functional evidence that ARF1 may negatively regulate mTORC2. In summary, we present a new method of studying endogenous mTORC2, a resource of RICTOR/mTORC2 protein interactions in living cells, and a potential mechanism of mTORC2 regulation by the ARF1 GTPase.
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Affiliation(s)
- Amelia K Luciano
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Ekaterina Korobkina
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Scott P Lyons
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - John A Haley
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Shelagh Fluharty
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Su Myung Jung
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755; Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - David A Guertin
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605; Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605.
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Raptor downregulation rescues neuronal phenotypes in mouse models of Tuberous Sclerosis Complex. Nat Commun 2022; 13:4665. [PMID: 35945201 PMCID: PMC9363483 DOI: 10.1038/s41467-022-31961-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 07/08/2022] [Indexed: 12/16/2022] Open
Abstract
Tuberous Sclerosis Complex (TSC) is a neurodevelopmental disorder caused by mutations in the TSC1 or TSC2 genes, which encode proteins that negatively regulate mTOR complex 1 (mTORC1) signaling. Current treatment strategies focus on mTOR inhibition with rapamycin and its derivatives. While effective at improving some aspects of TSC, chronic rapamycin inhibits both mTORC1 and mTORC2 and is associated with systemic side-effects. It is currently unknown which mTOR complex is most relevant for TSC-related brain phenotypes. Here we used genetic strategies to selectively reduce neuronal mTORC1 or mTORC2 activity in mouse models of TSC. We find that reduction of the mTORC1 component Raptor, but not the mTORC2 component Rictor, rebalanced mTOR signaling in Tsc1 knock-out neurons. Raptor reduction was sufficient to improve several TSC-related phenotypes including neuronal hypertrophy, macrocephaly, impaired myelination, network hyperactivity, and premature mortality. Raptor downregulation represents a promising potential therapeutic intervention for the neurological manifestations of TSC.
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35
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Yu Z, Chen J, Takagi E, Wang F, Saha B, Liu X, Joubert LM, Gleason CE, Jin M, Li C, Nowotny C, Agard D, Cheng Y, Pearce D. Interactions between mTORC2 core subunits Rictor and mSin1 dictate selective and context-dependent phosphorylation of substrate kinases SGK1 and Akt. J Biol Chem 2022; 298:102288. [PMID: 35926713 PMCID: PMC9440446 DOI: 10.1016/j.jbc.2022.102288] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 07/04/2022] [Accepted: 07/05/2022] [Indexed: 12/02/2022] Open
Abstract
Mechanistic target of rapamycin complex 2 (mTORC2) is a multi-subunit kinase complex, central to multiple essential signaling pathways. Two core subunits, Rictor and mSin1, distinguish it from the related mTORC1 and support context-dependent phosphorylation of its substrates. mTORC2 structures have been determined previously; however, important questions remain, particularly regarding the structural determinants mediating substrate specificity and context-dependent activity. Here, we used cryo-EM to obtain high-resolution structures of the human mTORC2 apo-complex in the presence of substrates Akt and SGK1. Using functional assays, we then tested predictions suggested by substrate-induced structural changes in mTORC2. For the first time, we visualized in the apo-state the side chain interactions between Rictor and mTOR that sterically occlude recruitment of mTORC1 substrates and confer resistance to the mTORC1 inhibitor rapamycin. Also in the apo-state, we observed that mSin1 formed extensive contacts with Rictor via a pair of short α-helices nestled between two Rictor helical repeat clusters, as well as by an extended strand that makes multiple weak contacts with Rictor helical cluster 1. In co-complex structures, we found that SGK1, but not Akt, markedly altered the conformation of the mSin1 N-terminal extended strand, disrupting multiple weak interactions while inducing a large rotation of mSin1 residue Arg-83, which then interacts with a patch of negatively charged residues within Rictor. Finally, we demonstrate mutation of Arg-83 to Ala selectively disrupts mTORC2-dependent phosphorylation of SGK1, but not of Akt, supporting context-dependent substrate selection. These findings provide new structural and functional insights into mTORC2 specificity and context-dependent activity.
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Affiliation(s)
- Zanlin Yu
- Department of Biochemistry and Biophysics, University of California, San Francisco, California, USA
| | - Junliang Chen
- Department of Medicine, Division of Nephrology, and Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Enzo Takagi
- Department of Medicine, Division of Nephrology, and Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Feng Wang
- Department of Biochemistry and Biophysics, University of California, San Francisco, California, USA
| | - Bidisha Saha
- Department of Medicine, Division of Nephrology, and Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Xi Liu
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, USA
| | - Lydia-Marie Joubert
- Division of CryoEM and Bioimaging, SSRL, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California, USA
| | - Catherine E Gleason
- Department of Medicine, Division of Nephrology, and Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Mingliang Jin
- Department of Biochemistry and Biophysics, University of California, San Francisco, California, USA
| | - Chengmin Li
- Department of Biochemistry and Biophysics, University of California, San Francisco, California, USA
| | - Carlos Nowotny
- Department of Biochemistry and Biophysics, University of California, San Francisco, California, USA
| | - David Agard
- Department of Biochemistry and Biophysics, University of California, San Francisco, California, USA
| | - Yifan Cheng
- Department of Biochemistry and Biophysics, University of California, San Francisco, California, USA; Howard Hughes Medical Institute, University of California San Francisco, San Francisco, California, USA
| | - David Pearce
- Department of Medicine, Division of Nephrology, and Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA.
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36
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Yasmin T. In silico comprehensive analysis of coding and non-coding SNPs in human mTOR protein. PLoS One 2022; 17:e0270919. [PMID: 35788771 PMCID: PMC9255762 DOI: 10.1371/journal.pone.0270919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 06/17/2022] [Indexed: 11/21/2022] Open
Abstract
The mammalian/mechanistic target of rapamycin (mTOR) protein is an important growth regulator and has been linked with multiple diseases including cancer and diabetes. Non-synonymous mutations of this gene have already been found in patients with renal clear cell carcinoma, melanoma, and acute lymphoid leukemia among many others. Such mutations can potentially affect a protein’s structure and hence its functions. In this study, therefore, the most deleterious SNPs of mTOR protein have been determined to identify potential biomarkers for various disease treatments. The aim is to generate a structured dataset of the mTOR gene’s SNPs that may prove to be an asset for the identification and treatment of multiple diseases associated with the target gene. Both sequence and structure-based approaches were adopted and a wide variety of bioinformatics tools were applied to analyze the SNPs of mTOR protein. In total 11 nsSNPs have been filtered out of 2178 nsSNPs along with two non-coding variations. All of the nsSNPs were found to destabilize the protein structure and disrupt its function. While R619C, A1513D, and T1977R mutations were shown to alter C alpha distances and bond angles of the mTOR protein, L509Q, R619C and N2043S were predicted to disrupt the mTOR protein’s interaction with NBS1 protein and FKBP1A/rapamycin complex. In addition, one of the non-coding SNPs was shown to alter miRNA binding sites. Characterizing nsSNPs and non-coding SNPs and their harmful effects on a protein’s structure and functions will enable researchers to understand the critical impact of mutations on the molecular mechanisms of various diseases. This will ultimately lead to the identification of potential targets for disease diagnosis and therapeutic interventions.
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Affiliation(s)
- Tahirah Yasmin
- Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, Bangladesh
- * E-mail:
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37
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mTOR substrate phosphorylation in growth control. Cell 2022; 185:1814-1836. [PMID: 35580586 DOI: 10.1016/j.cell.2022.04.013] [Citation(s) in RCA: 145] [Impact Index Per Article: 72.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/05/2022] [Accepted: 04/07/2022] [Indexed: 12/20/2022]
Abstract
The target of rapamycin (TOR), discovered 30 years ago, is a highly conserved serine/threonine protein kinase that plays a central role in regulating cell growth and metabolism. It is activated by nutrients, growth factors, and cellular energy. TOR forms two structurally and functionally distinct complexes, TORC1 and TORC2. TOR signaling activates cell growth, defined as an increase in biomass, by stimulating anabolic metabolism while inhibiting catabolic processes. With emphasis on mammalian TOR (mTOR), we comprehensively reviewed the literature and identified all reported direct substrates. In the context of recent structural information, we discuss how mTORC1 and mTORC2, despite having a common catalytic subunit, phosphorylate distinct substrates. We conclude that the two complexes recruit different substrates to phosphorylate a common, minimal motif.
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38
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Preparation of Novel Pyrazolo[4,3- e]tetrazolo[1,5- b][1,2,4]triazine Sulfonamides and Their Experimental and Computational Biological Studies. Int J Mol Sci 2022; 23:ijms23115892. [PMID: 35682571 PMCID: PMC9180621 DOI: 10.3390/ijms23115892] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 02/04/2023] Open
Abstract
Pyrazolo[4,3-e]tetrazolo[1,5-b][1,2,4]triazine sulfonamides constitute a novel class of heterocyclic compounds with broad biological activity, including anticancer properties. Investigated in this study, MM-compounds (MM134, MM136, MM137, and MM139) exhibited cytotoxic and proapoptotic activity against cancer cell lines (BxPC-3, PC-3, and HCT-116) in nanomolar concentrations without causing cytotoxicity in normal cells (L929 and WI38). In silico predictions indicate that tested compounds exhibit favorable pharmacokinetic profiles and may exert anticancer activity through the inhibition of BTK kinase, the AKT-mTOR pathway and PD1-PD-L1 interaction. Our findings point out that these sulfonamide derivatives may constitute a source of new anticancer drugs after optimization.
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39
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Abstract
Both the mTORC2 and Ras-ERK pathways respond to growth factor stimulation and play critical roles in cell growth and proliferation, disarray of these pathways leads to many diseases, especially cancer. These two signaling pathways crosstalk at many levels; recently it's become clear that the SIN1 component of mTORC2 could interact with Ras family small GTPases, but how these two proteins interact at the molecular level and the functional outcomes of this interaction remain to be addressed. In this work we determined the high-resolution structure of Ras-SIN1 complexes and revealed the detailed interaction mechanism. We also showed that Ras-SIN1 association inhibits insulin-induced ERK activation. Insights from this work could improve our understanding of the disease-causing mechanism of errant mTORC2 or Ras proteins. Over the years it has been established that SIN1, a key component of mTORC2, could interact with Ras family small GTPases through its Ras-binding domain (RBD). The physical association of Ras and SIN1/mTORC2 could potentially affect both mTORC2 and Ras-ERK pathways. To decipher the precise molecular mechanism of this interaction, we determined the high-resolution structures of HRas/KRas-SIN1 RBD complexes, showing the detailed interaction interface. Mutation of critical interface residues abolished Ras-SIN1 interaction and in SIN1 knockout cells we demonstrated that Ras-SIN1 association promotes SGK1 activity but inhibits insulin-induced ERK activation. With structural comparison and competition fluorescence resonance energy transfer (FRET) assays we showed that HRas-SIN1 RBD association is much weaker than HRas-Raf1 RBD but is slightly stronger than HRas-PI3K RBD interaction, providing a possible explanation for the different outcome of insulin or EGF stimulation. We also found that SIN1 isoform lacking the PH domain binds stronger to Ras than other longer isoforms and the PH domain appears to have an inhibitory effect on Ras-SIN1 binding. In addition, we uncovered a Ras dimerization interface that could be critical for Ras oligomerization. Our results advance our understanding of Ras-SIN1 association and crosstalk between growth factor-stimulated pathways.
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40
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Simcox J, Lamming DW. The central moTOR of metabolism. Dev Cell 2022; 57:691-706. [PMID: 35316619 PMCID: PMC9004513 DOI: 10.1016/j.devcel.2022.02.024] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/20/2022] [Accepted: 02/24/2022] [Indexed: 12/21/2022]
Abstract
The protein kinase mechanistic target of rapamycin (mTOR) functions as a central regulator of metabolism, integrating diverse nutritional and hormonal cues to control anabolic processes, organismal physiology, and even aging. This review discusses the current state of knowledge regarding the regulation of mTOR signaling and the metabolic regulation of the four macromolecular building blocks of the cell: carbohydrate, nucleic acid, lipid, and protein by mTOR. We review the role of mTOR in the control of organismal physiology and aging through its action in key tissues and discuss the potential for clinical translation of mTOR inhibition for the treatment and prevention of diseases of aging.
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Affiliation(s)
- Judith Simcox
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA.
| | - Dudley W Lamming
- William S. Middleton Memorial Veterans Hospital, Madison, WI, USA; Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.
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41
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Tsverov J, Yegorov K, Powers T. Identification of defined structural elements within TOR2 kinase required for TOR Complex 2 assembly and function in S. cerevisiae. Mol Biol Cell 2022; 33:ar44. [PMID: 35293776 PMCID: PMC9282017 DOI: 10.1091/mbc.e21-12-0611] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
mTOR is a large protein kinase that assembles into two multi-subunit protein complexes, mTORC1 and mTORC2, to regulate cell growth in eukaryotic cells. While significant progress has been made in our understanding of the composition and structure of these complexes, important questions remain regarding the role of specific sequences within mTOR important for complex formation and activity. To address these issues, we have used a molecular genetic approach to explore TOR Complex assembly in budding yeast, where two closely related TOR paralogs, TOR1 and TOR2, partition preferentially into TORC1 versus TORC2, respectively. We previously identified a ∼500 amino acid segment within the N-terminal half of each protein, termed the Major Assembly Specificity (MAS) Domain, which can govern specificity in formation of each complex. In this study, we have extended the use of chimeric TOR1-TOR2 genes as a "sensitized" genetic system to identify specific subdomains rendered essential for TORC2 function, using synthetic lethal interaction analyses. Our findings reveal important design principles underlying the dimeric assembly of TORC2, as well as identify specific segments within the MAS domain critical for TORC2 function, to a level approaching single amino acid resolution. Together these findings highlight the complex and cooperative nature of TOR Complex assembly and function.
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Affiliation(s)
- Jennifer Tsverov
- Department of Molecular and Cellular Biology, College of Biological Sciences, UC Davis
| | - Kristina Yegorov
- Department of Molecular and Cellular Biology, College of Biological Sciences, UC Davis
| | - Ted Powers
- Department of Molecular and Cellular Biology, College of Biological Sciences, UC Davis
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42
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Baffi TR, Newton AC. Protein kinase C: release from quarantine by mTORC2. Trends Biochem Sci 2022; 47:518-530. [DOI: 10.1016/j.tibs.2022.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 02/14/2022] [Accepted: 03/02/2022] [Indexed: 01/31/2023]
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43
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Green CL, Lamming DW, Fontana L. Molecular mechanisms of dietary restriction promoting health and longevity. Nat Rev Mol Cell Biol 2022; 23:56-73. [PMID: 34518687 PMCID: PMC8692439 DOI: 10.1038/s41580-021-00411-4] [Citation(s) in RCA: 243] [Impact Index Per Article: 121.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2021] [Indexed: 02/08/2023]
Abstract
Dietary restriction with adequate nutrition is the gold standard for delaying ageing and extending healthspan and lifespan in diverse species, including rodents and non-human primates. In this Review, we discuss the effects of dietary restriction in these mammalian model organisms and discuss accumulating data that suggest that dietary restriction results in many of the same physiological, metabolic and molecular changes responsible for the prevention of multiple ageing-associated diseases in humans. We further discuss how different forms of fasting, protein restriction and specific reductions in the levels of essential amino acids such as methionine and the branched-chain amino acids selectively impact the activity of AKT, FOXO, mTOR, nicotinamide adenine dinucleotide (NAD+), AMP-activated protein kinase (AMPK) and fibroblast growth factor 21 (FGF21), which are key components of some of the most important nutrient-sensing geroprotective signalling pathways that promote healthy longevity.
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Affiliation(s)
- Cara L Green
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
- William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Dudley W Lamming
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
- William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Luigi Fontana
- Charles Perkins Center, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia.
- Department of Endocrinology, Royal Prince Alfred Hospital, Sydney, NSW, Australia.
- Department of Clinical and Experimental Sciences, Brescia University School of Medicine, Brescia, Italy.
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44
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Cui D, Qu R, Liu D, Xiong X, Liang T, Zhao Y. The Cross Talk Between p53 and mTOR Pathways in Response to Physiological and Genotoxic Stresses. Front Cell Dev Biol 2021; 9:775507. [PMID: 34869377 PMCID: PMC8638743 DOI: 10.3389/fcell.2021.775507] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 11/03/2021] [Indexed: 12/25/2022] Open
Abstract
The tumor suppressor p53 is activated upon multiple cellular stresses, including DNA damage, oncogene activation, ribosomal stress, and hypoxia, to induce cell cycle arrest, apoptosis, and senescence. Mammalian target of rapamycin (mTOR), an evolutionarily conserved serine/threonine protein kinase, serves as a central regulator of cell growth, proliferation, and survival by coordinating nutrients, energy, growth factors, and oxygen levels. p53 dysfunction and mTOR pathway hyperactivation are hallmarks of human cancer. The balance between response to stresses or commitment to cell proliferation and survival is governed by various regulatory loops between the p53 and mTOR pathways. In this review, we first briefly introduce the tumor suppressor p53 and then describe the upstream regulators and downstream effectors of the mTOR pathway. Next, we discuss the role of p53 in regulating the mTOR pathway through its transcriptional and non-transcriptional effects. We further describe the complicated role of the mTOR pathway in modulating p53 activity. Finally, we discuss the current knowledge and future perspectives on the coordinated regulation of the p53 and mTOR pathways.
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Affiliation(s)
- Danrui Cui
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Cancer Center, Zhejiang University, Hangzhou, China
| | - Ruirui Qu
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Dian Liu
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiufang Xiong
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China.,Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Tingbo Liang
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Cancer Center, Zhejiang University, Hangzhou, China
| | - Yongchao Zhao
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Cancer Center, Zhejiang University, Hangzhou, China.,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
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45
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Herbst DA, Esbin MN, Louder RK, Dugast-Darzacq C, Dailey GM, Fang Q, Darzacq X, Tjian R, Nogales E. Structure of the human SAGA coactivator complex. Nat Struct Mol Biol 2021; 28:989-996. [PMID: 34811519 PMCID: PMC8660637 DOI: 10.1038/s41594-021-00682-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 10/05/2021] [Indexed: 12/16/2022]
Abstract
The SAGA complex is a regulatory hub involved in gene regulation, chromatin modification, DNA damage repair and signaling. While structures of yeast SAGA (ySAGA) have been reported, there are noteworthy functional and compositional differences for this complex in metazoans. Here we present the cryogenic-electron microscopy (cryo-EM) structure of human SAGA (hSAGA) and show how the arrangement of distinct structural elements results in a globally divergent organization from that of yeast, with a different interface tethering the core module to the TRRAP subunit, resulting in a dramatically altered geometry of functional elements and with the integration of a metazoan-specific splicing module. Our hSAGA structure reveals the presence of an inositol hexakisphosphate (InsP6) binding site in TRRAP and an unusual property of its pseudo-(Ψ)PIKK. Finally, we map human disease mutations, thus providing the needed framework for structure-guided drug design of this important therapeutic target for human developmental diseases and cancer.
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Affiliation(s)
- Dominik A Herbst
- California Institute for Quantitative Biology (QB3), University of California, Berkeley, CA, USA
- Molecular Biophysics and Integrated Bio-Imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Meagan N Esbin
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Biophysics Graduate Group, University of California, Berkeley, CA, USA
| | - Robert K Louder
- California Institute for Quantitative Biology (QB3), University of California, Berkeley, CA, USA
- Biophysics Graduate Group, University of California, Berkeley, CA, USA
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Claire Dugast-Darzacq
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Gina M Dailey
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Qianglin Fang
- California Institute for Quantitative Biology (QB3), University of California, Berkeley, CA, USA
- Molecular Biophysics and Integrated Bio-Imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- School of Public Health, Sun Yat-sen University, Shenzhen, China
| | - Xavier Darzacq
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Robert Tjian
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA
| | - Eva Nogales
- California Institute for Quantitative Biology (QB3), University of California, Berkeley, CA, USA.
- Molecular Biophysics and Integrated Bio-Imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA.
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46
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Vos SM. Chronicles of the human SAGA co-activator complex. Nat Struct Mol Biol 2021; 28:959-960. [PMID: 34819676 DOI: 10.1038/s41594-021-00696-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Seychelle M Vos
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
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47
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Structure of the Human TELO2-TTI1-TTI2 Complex. J Mol Biol 2021; 434:167370. [PMID: 34838521 DOI: 10.1016/j.jmb.2021.167370] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 11/10/2021] [Accepted: 11/15/2021] [Indexed: 11/21/2022]
Abstract
Phosphatidylinositol 3-kinase-related protein kinases (PIKKs) play critical roles in various metabolic pathways related to cell proliferation and survival. The TELO2-TTI1-TTI2 (TTT) complex has been proposed to recognize newly synthesized PIKKs and to deliver them to the R2TP complex (RUVBL1-RUVBL2-RPAP3-PIH1D1) and the heat shock protein 90 chaperone, thereby supporting their folding and assembly. Here, we determined the cryo-EM structure of the TTT complex at an average resolution of 4.2 Å. We describe the full-length structures of TTI1 and TELO2, and a partial structure of TTI2. All three proteins form elongated helical repeat structures. TTI1 provides a platform on which TELO2 and TTI2 bind to its central region and C-terminal end, respectively. The TELO2 C-terminal domain (CTD) is required for the interaction with TTI1 and recruitment of Ataxia-telangiectasia mutated (ATM). The N- and C-terminal segments of TTI1 recognize the FRAP-ATM-TRRAP (FAT) domain and the N-terminal HEAT repeats of ATM, respectively. The TELO2 CTD and TTI1 N- and C-terminal segments are required for cell survival in response to ionizing radiation.
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48
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Shams R, Ito Y, Miyatake H. Mapping of mTOR drug targets: Featured platforms for anti-cancer drug discovery. Pharmacol Ther 2021; 232:108012. [PMID: 34624427 DOI: 10.1016/j.pharmthera.2021.108012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/25/2021] [Accepted: 09/28/2021] [Indexed: 12/12/2022]
Abstract
The mammalian/mechanistic target of rapamycin (mTOR) is a regulatory protein kinase involved in cell growth and proliferation. mTOR is usually assembled in two different complexes with different regulatory mechanisms, mTOR complex 1 (mTORC1) and mTORC2, which are involved in different functions such as cell proliferation and cytoskeleton assembly, respectively. In cancer cells, mTOR is hyperactivated in response to metabolic alterations and/or oncogenic signals to overcome the stressful microenvironments. Therefore, recent research progress for mTOR inhibition involves a variety of compounds that have been developed to disturb the metabolic processes of cancer cells through mTOR inhibition. In addition to competitive or allosteric inhibition, a new inhibition strategy that emerged mTOR complexes destabilization has recently been a concern. Here, we review the history of mTOR and its inhibition, along with the timeline of the mTOR inhibitors. We also introduce prospective drug targets to inhibit mTOR by disrupting the complexation of the components with peptides and small molecules.
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Affiliation(s)
- Raef Shams
- Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198, Japan; Department of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan.
| | - Yoshihiro Ito
- Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198, Japan; Nano Medical Engineering Laboratory, RIKEN Cluster for Pioneering Research, RIKEN, Wako, Saitama 351-0198, Japan
| | - Hideyuki Miyatake
- Department of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan; Nano Medical Engineering Laboratory, RIKEN Cluster for Pioneering Research, RIKEN, Wako, Saitama 351-0198, Japan.
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49
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Yang G, Francis D, Krycer JR, Larance M, Zhang Z, Novotny CJ, Diaz-Vegas A, Shokat KM, James DE. Dissecting the biology of mTORC1 beyond rapamycin. Sci Signal 2021; 14:eabe0161. [PMID: 34546793 DOI: 10.1126/scisignal.abe0161] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
[Figure: see text].
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Affiliation(s)
- Guang Yang
- University of Sydney, School of life and Environmental Sciences, Charles Perkins Centre, Sydney, New South Wales 2006, Australia
| | - Deanne Francis
- University of Sydney, School of life and Environmental Sciences, Charles Perkins Centre, Sydney, New South Wales 2006, Australia
| | - James R Krycer
- University of Sydney, School of life and Environmental Sciences, Charles Perkins Centre, Sydney, New South Wales 2006, Australia
| | - Mark Larance
- University of Sydney, School of life and Environmental Sciences, Charles Perkins Centre, Sydney, New South Wales 2006, Australia
| | - Ziyang Zhang
- Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, 600 16th Street, San Francisco, CA 94143, USA
| | - Chris J Novotny
- Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, 600 16th Street, San Francisco, CA 94143, USA
| | - Alexis Diaz-Vegas
- University of Sydney, School of life and Environmental Sciences, Charles Perkins Centre, Sydney, New South Wales 2006, Australia
| | - Kevan M Shokat
- Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, 600 16th Street, San Francisco, CA 94143, USA
| | - David E James
- University of Sydney, School of life and Environmental Sciences, Charles Perkins Centre, Sydney, New South Wales 2006, Australia.,University of Sydney, Sydney Medical School, Sydney, New South Wales 2006, Australia
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Wälchli M, Berneiser K, Mangia F, Imseng S, Craigie LM, Stuttfeld E, Hall MN, Maier T. Regulation of human mTOR complexes by DEPTOR. eLife 2021; 10:e70871. [PMID: 34519268 PMCID: PMC8439649 DOI: 10.7554/elife.70871] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 07/31/2021] [Indexed: 11/30/2022] Open
Abstract
The vertebrate-specific DEP domain-containing mTOR interacting protein (DEPTOR), an oncoprotein or tumor suppressor, has important roles in metabolism, immunity, and cancer. It is the only protein that binds and regulates both complexes of mammalian target of rapamycin (mTOR), a central regulator of cell growth. Biochemical analysis and cryo-EM reconstructions of DEPTOR bound to human mTOR complex 1 (mTORC1) and mTORC2 reveal that both structured regions of DEPTOR, the PDZ domain and the DEP domain tandem (DEPt), are involved in mTOR interaction. The PDZ domain binds tightly with mildly activating effect, but then acts as an anchor for DEPt association that allosterically suppresses mTOR activation. The binding interfaces of the PDZ domain and DEPt also support further regulation by other signaling pathways. A separate, substrate-like mode of interaction for DEPTOR phosphorylation by mTOR complexes rationalizes inhibition of non-stimulated mTOR activity at higher DEPTOR concentrations. The multifaceted interplay between DEPTOR and mTOR provides a basis for understanding the divergent roles of DEPTOR in physiology and opens new routes for targeting the mTOR-DEPTOR interaction in disease.
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Affiliation(s)
| | | | | | | | | | | | | | - Timm Maier
- Biozentrum, University of BaselBaselSwitzerland
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