1
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Walsh ZH, Shah P, Kothapalli N, Shah SB, Nikolenyi G, Brodtman DZ, Leuzzi G, Rogava M, Mu M, Ho P, Abuzaid S, Vasan N, AlQuraishi M, Milner JD, Ciccia A, Melms JC, Izar B. Mapping variant effects on anti-tumor hallmarks of primary human T cells with base-editing screens. Nat Biotechnol 2024:10.1038/s41587-024-02235-x. [PMID: 38783148 DOI: 10.1038/s41587-024-02235-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 04/10/2024] [Indexed: 05/25/2024]
Abstract
Single-nucleotide variants (SNVs) in key T cell genes can drive clinical pathologies and could be repurposed to improve cellular cancer immunotherapies. Here, we perform massively parallel base-editing screens to generate thousands of variants at gene loci annotated with known or potential clinical relevance. We discover a broad landscape of putative gain-of-function (GOF) and loss-of-function (LOF) mutations, including in PIK3CD and the gene encoding its regulatory subunit, PIK3R1, LCK, SOS1, AKT1 and RHOA. Base editing of PIK3CD and PIK3R1 variants in T cells with an engineered T cell receptor specific to a melanoma epitope or in different generations of CD19 chimeric antigen receptor (CAR) T cells demonstrates that discovered GOF variants, but not LOF or silent mutation controls, enhanced signaling, cytokine production and lysis of cognate melanoma and leukemia cell models, respectively. Additionally, we show that generations of CD19 CAR T cells engineered with PIK3CD GOF mutations demonstrate enhanced antigen-specific signaling, cytokine production and leukemia cell killing, including when benchmarked against other recent strategies.
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Affiliation(s)
- Zachary H Walsh
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA
- Columbia Center for Translational Immunology, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Parin Shah
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA
- Columbia Center for Translational Immunology, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Neeharika Kothapalli
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Shivem B Shah
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Gergo Nikolenyi
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - D Zack Brodtman
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA
- Columbia Center for Translational Immunology, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Giuseppe Leuzzi
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
- Department of Genetics and Development, Columbia University Medical Center, New York, NY, USA
| | - Meri Rogava
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA
- Columbia Center for Translational Immunology, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Michael Mu
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA
- Columbia Center for Translational Immunology, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Patricia Ho
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA
- Columbia Center for Translational Immunology, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Sinan Abuzaid
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA
- Columbia Center for Translational Immunology, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Neil Vasan
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Mohammed AlQuraishi
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Joshua D Milner
- Department of Pediatrics, Columbia University Irving Medical Center, New York, NY, USA
| | - Alberto Ciccia
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
- Department of Genetics and Development, Columbia University Medical Center, New York, NY, USA
| | - Johannes C Melms
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA
- Columbia Center for Translational Immunology, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Benjamin Izar
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
- Department of Medicine, Division of Hematology and Oncology, Columbia University Irving Medical Center, New York, NY, USA.
- Columbia Center for Translational Immunology, New York, NY, USA.
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA.
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA.
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2
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Wu J, Li X, Wu C, Wang Y, Zhang J. Current advances and development strategies of targeting son of sevenless 1 (SOS1) in drug discovery. Eur J Med Chem 2024; 268:116282. [PMID: 38430853 DOI: 10.1016/j.ejmech.2024.116282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/20/2024] [Accepted: 02/23/2024] [Indexed: 03/05/2024]
Abstract
The Son of Sevenless 1 (SOS1) guanine nucleotide exchange factor, prevalent across eukaryotic species, plays a pivotal role in facilitating the attachment of RAS protein to GTP, thereby regulating the activation of intracellular RAS proteins. This regulation is part of a feedback mechanism involving SOS1, which allows both activators and inhibitors of SOS1 to exert control over downstream signaling pathways, demonstrating potential anti-tumor effects. Predominantly, small molecule modulators that target SOS1 focus on a hydrophobic pocket within the CDC25 protein domain. The effectiveness of these modulators largely depends on their ability to interact with specific amino acids, notably Phe890 and Tyr884. This interaction is crucial for influencing the protein-protein interaction (PPI) between RAS and the catalytic domain of SOS1. Currently, most small molecule modulators targeting SOS1 are in the preclinical research phase, with a few advancing to clinical trials. This progression raises safety concerns, making the assurance of drug safety a primary consideration alongside the enhancement of efficacy in the development of SOS1 modulators. This review encapsulates recent advancements in the chemical categorization of SOS1 inhibitors and activators. It delves into the evolution of small molecule modulation targeting SOS1 and offers perspectives on the design of future generations of selective SOS1 small molecule modulators.
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Affiliation(s)
- Jialin Wu
- Department of Neurology, Neuro-system and Multimorbidity Laboratory and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China; Department of Pulmonary and Critical Care Medicine, Targeted Tracer Research and Development Laboratory, Institute of Respiratory Health, Frontiers Science Center for Disease-related Molecular Network, Precision Medicine Key Laboratory of Sichuan Province & Precision Medicine Research Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Xiaoxue Li
- Department of Dermatology, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Chengyong Wu
- Department of Neurology, Neuro-system and Multimorbidity Laboratory and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China; Department of Pulmonary and Critical Care Medicine, Targeted Tracer Research and Development Laboratory, Institute of Respiratory Health, Frontiers Science Center for Disease-related Molecular Network, Precision Medicine Key Laboratory of Sichuan Province & Precision Medicine Research Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yuxi Wang
- Department of Pulmonary and Critical Care Medicine, Targeted Tracer Research and Development Laboratory, Institute of Respiratory Health, Frontiers Science Center for Disease-related Molecular Network, Precision Medicine Key Laboratory of Sichuan Province & Precision Medicine Research Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - Jifa Zhang
- Department of Neurology, Neuro-system and Multimorbidity Laboratory and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
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3
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Pang X, Cui D, Lv B, Wang CY. Discovery of Potent SOS1 PROTACs with Effective Antitumor Activities against NCI-H358 Tumor Cells In Vitro/In Vivo. J Med Chem 2024; 67:1563-1579. [PMID: 38206836 DOI: 10.1021/acs.jmedchem.3c02135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Directly targeted KRAS inhibitors are now facing resistance problems, which might be partially solved by the combination of SOS1 inhibitors with KRAS inhibitors. However, this combination may still have some resistance mitigation potential. Comparatively, SOS1 PROTAC may have promising applications in addressing the drug resistance problem by degrading the SOS1 protein. Herein, we report the discovery of novel SOS1 PROTACs and their antitumor activity both in vitro and in vivo. In vitro studies demonstrated that degrader 4 had strong inhibitory effects on the proliferation of NCI-H358 cells with IC50 of 5 nM, together with significant degradation of SOS1 protein with DC50 of 13 nM. In the NCI-H358 xenograft model, degrader 4 exhibited significant antitumor activities with TGITV values of 58.8% at 30 mg/kg bid. The PK and safety profiles also supported degrader 4 for further studies as an effective tool compound.
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Affiliation(s)
- Xudong Pang
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
- Shanghai Zelgen Pharma-Tech Co., Ltd., Building 3, No. 999, Cailun Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
| | - Dawei Cui
- Shanghai Zelgen Pharma-Tech Co., Ltd., Building 3, No. 999, Cailun Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
| | - Binhua Lv
- Shanghai Zelgen Pharma-Tech Co., Ltd., Building 3, No. 999, Cailun Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
| | - Cheng-Yun Wang
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
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4
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Walsh ZH, Shah P, Kothapalli N, Nikolenyi G, Shah SB, Leuzzi G, Mu M, Ho P, Abuzaid S, Brodtman ZD, Vasan N, AlQuraishi M, Milner JD, Ciccia A, Melms JC, Izar B. Massively parallel base editing screens to map variant effects on anti-tumor hallmarks of primary human T cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.13.571465. [PMID: 38168306 PMCID: PMC10760091 DOI: 10.1101/2023.12.13.571465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Base editing enables generation of single nucleotide variants, but large-scale screening in primary human T cells is limited due to low editing efficiency, among other challenges 1 . Here, we developed a high-throughput approach for high-efficiency and massively parallel adenine and cytosine base-editor screening in primary human T cells. We performed multiple large-scale screens editing 102 genes with central functions in T cells and full-length tiling mutagenesis of selected genes, and read out variant effects on hallmarks of T cell anti-tumor immunity, including activation, proliferation, and cytokine production. We discovered a broad landscape of gain- and loss-of-function mutations, including in PIK3CD and its regulatory subunit encoded by PIK3R1, LCK , AKT1, CTLA-4 and JAK1 . We identified variants that affected several (e.g., PIK3CD C416R) or only selected (e.g. LCK Y505C) hallmarks of T cell activity, and functionally validated several hits by probing downstream signaling nodes and testing their impact on T cell polyfunctionality and proliferation. Using primary human T cells in which we engineered a T cell receptor (TCR) specific to a commonly presented tumor testis antigen as a model for cellular immunotherapy, we demonstrate that base edits identified in our screens can tune specific or broad T cell functions and ultimately improve tumor elimination while exerting minimal off-target activity. In summary, we present the first large-scale base editing screen in primary human T cells and provide a framework for scalable and targeted base editing at high efficiency. Coupled with multi-modal phenotypic mapping, we accurately nominate variants that produce a desirable T cell state and leverage these synthetic proteins to improve models of cellular cancer immunotherapies.
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5
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Chen T, Tang X, Wang Z, Feng F, Xu C, Zhao Q, Wu Y, Sun H, Chen Y. Inhibition of Son of Sevenless Homologue 1 (SOS1): Promising therapeutic treatment for KRAS-mutant cancers. Eur J Med Chem 2023; 261:115828. [PMID: 37778239 DOI: 10.1016/j.ejmech.2023.115828] [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: 07/04/2023] [Revised: 09/19/2023] [Accepted: 09/21/2023] [Indexed: 10/03/2023]
Abstract
Kristen rat sarcoma (KRAS) is one of the most common oncogenes in human cancers. As a guanine nucleotide exchange factor, Son of Sevenless Homologue 1 (SOS1) represents a potential therapeutic concept for the treatment of KRAS-mutant cancers because of its activation on KRAS and downstream signaling pathways. In this review, we provide a comprehensive overview of the structure, biological function, and regulation of SOS1. We also focus on the recent advances in SOS1 inhibitors and emphasize their binding modes, structure-activity relationships and pharmacological activities. We hope that this publication can provide a comprehensive compendium on the rational design of SOS1 inhibitors.
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Affiliation(s)
- Tingkai Chen
- School of Pharmacy, China Pharmaceutical University, Nanjing, 211198, People's Republic of China
| | - Xu Tang
- School of Pharmacy, China Pharmaceutical University, Nanjing, 211198, People's Republic of China
| | - Zhenqi Wang
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China
| | - Feng Feng
- School of Pharmacy, Nanjing Medical University, 211166, Nanjing, People's Republic of China
| | - Chunlei Xu
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China
| | - Qun Zhao
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China
| | - Yulan Wu
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China
| | - Haopeng Sun
- School of Pharmacy, China Pharmaceutical University, Nanjing, 211198, People's Republic of China.
| | - Yao Chen
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China.
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6
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Powis G, Meuillet EJ, Indarte M, Booher G, Kirkpatrick L. Pleckstrin Homology [PH] domain, structure, mechanism, and contribution to human disease. Biomed Pharmacother 2023; 165:115024. [PMID: 37399719 DOI: 10.1016/j.biopha.2023.115024] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 06/14/2023] [Indexed: 07/05/2023] Open
Abstract
The pleckstrin homology [PH] domain is a structural fold found in more than 250 proteins making it the 11th most common domain in the human proteome. 25% of family members have more than one PH domain and some PH domains are split by one, or several other, protein domains although still folding to give functioning PH domains. We review mechanisms of PH domain activity, the role PH domain mutation plays in human disease including cancer, hyperproliferation, neurodegeneration, inflammation, and infection, and discuss pharmacotherapeutic approaches to regulate PH domain activity for the treatment of human disease. Almost half PH domain family members bind phosphatidylinositols [PIs] that attach the host protein to cell membranes where they interact with other membrane proteins to give signaling complexes or cytoskeleton scaffold platforms. A PH domain in its native state may fold over other protein domains thereby preventing substrate access to a catalytic site or binding with other proteins. The resulting autoinhibition can be released by PI binding to the PH domain, or by protein phosphorylation thus providing fine tuning of the cellular control of PH domain protein activity. For many years the PH domain was thought to be undruggable until high-resolution structures of human PH domains allowed structure-based design of novel inhibitors that selectively bind the PH domain. Allosteric inhibitors of the Akt1 PH domain have already been tested in cancer patients and for proteus syndrome, with several other PH domain inhibitors in preclinical development for treatment of other human diseases.
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Affiliation(s)
- Garth Powis
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA.
| | | | - Martin Indarte
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA
| | - Garrett Booher
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA
| | - Lynn Kirkpatrick
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA
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7
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Manso JA, Carabias A, Sárkány Z, de Pereda JM, Pereira PJB, Macedo-Ribeiro S. Pathogen-specific structural features of Candida albicans Ras1 activation complex: uncovering new antifungal drug targets. mBio 2023; 14:e0063823. [PMID: 37526476 PMCID: PMC10470544 DOI: 10.1128/mbio.00638-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 06/16/2023] [Indexed: 08/02/2023] Open
Abstract
An important feature associated with Candida albicans pathogenicity is its ability to switch between yeast and hyphal forms, a process in which CaRas1 plays a key role. CaRas1 is activated by the guanine nucleotide exchange factor (GEF) CaCdc25, triggering hyphal growth-related signaling pathways through its conserved GTP-binding (G)-domain. An important function in hyphal growth has also been proposed for the long hypervariable region downstream the G-domain, whose unusual content of polyglutamine stretches and Q/N repeats make CaRas1 unique within Ras proteins. Despite its biological importance, both the structure of CaRas1 and the molecular basis of its activation by CaCdc25 remain unexplored. Here, we show that CaRas1 has an elongated shape and limited conformational flexibility and that its hypervariable region contains helical structural elements, likely forming an intramolecular coiled-coil. Functional assays disclosed that CaRas1-activation by CaCdc25 is highly efficient, with activities up to 2,000-fold higher than reported for human GEFs. The crystal structure of the CaCdc25 catalytic region revealed an active conformation for the α-helical hairpin, critical for CaRas1-activation, unveiling a specific region exclusive to CTG-clade species. Structural studies on CaRas1/CaCdc25 complexes also revealed an interaction surface clearly distinct from that of homologous human complexes. Furthermore, we identified an inhibitory synthetic peptide, prompting the proposal of a key regulatory mechanism for CaCdc25. To our knowledge, this is the first report of specific inhibition of the CaRas1-activation via targeting its GEF. This, together with their unique pathogen-structural features, disclose a set of novel strategies to specifically block this important virulence-related mechanism. IMPORTANCE Candida albicans is the main causative agent of candidiasis, the commonest fungal infection in humans. The eukaryotic nature of C. albicans and the rapid emergence of antifungal resistance raise the challenge of identifying novel drug targets to battle this prevalent and life-threatening disease. CaRas1 and CaCdc25 are key players in the activation of signaling pathways triggering multiple virulence traits, including the yeast-to-hypha interconversion. The structural similarity of the conserved G-domain of CaRas1 to those of human homologs and the lack of structural information on CaCdc25 has impeded progress in targeting these proteins. The unique structural and functional features for CaRas1 and CaCdc25 presented here, together with the identification of a synthetic peptide capable of specifically inhibiting the GEF activity of CaCdc25, open new possibilities to uncover new antifungal drug targets against C. albicans virulence.
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Affiliation(s)
- José A. Manso
- IBMC–Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- i3S–Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Arturo Carabias
- Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas-University of Salamanca, Salamanca, Spain
| | - Zsuzsa Sárkány
- IBMC–Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- i3S–Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - José M. de Pereda
- Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas-University of Salamanca, Salamanca, Spain
| | - Pedro José Barbosa Pereira
- IBMC–Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- i3S–Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Sandra Macedo-Ribeiro
- IBMC–Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- i3S–Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
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Leonard TA, Loose M, Martens S. The membrane surface as a platform that organizes cellular and biochemical processes. Dev Cell 2023; 58:1315-1332. [PMID: 37419118 DOI: 10.1016/j.devcel.2023.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 04/22/2023] [Accepted: 06/08/2023] [Indexed: 07/09/2023]
Abstract
Membranes are essential for life. They act as semi-permeable boundaries that define cells and organelles. In addition, their surfaces actively participate in biochemical reaction networks, where they confine proteins, align reaction partners, and directly control enzymatic activities. Membrane-localized reactions shape cellular membranes, define the identity of organelles, compartmentalize biochemical processes, and can even be the source of signaling gradients that originate at the plasma membrane and reach into the cytoplasm and nucleus. The membrane surface is, therefore, an essential platform upon which myriad cellular processes are scaffolded. In this review, we summarize our current understanding of the biophysics and biochemistry of membrane-localized reactions with particular focus on insights derived from reconstituted and cellular systems. We discuss how the interplay of cellular factors results in their self-organization, condensation, assembly, and activity, and the emergent properties derived from them.
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Affiliation(s)
- Thomas A Leonard
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Dr. Bohr-Gasse 9, 1030, Vienna, Austria; Medical University of Vienna, Center for Medical Biochemistry, Dr. Bohr-Gasse 9, 1030, Vienna, Austria.
| | - Martin Loose
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria.
| | - Sascha Martens
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Dr. Bohr-Gasse 9, 1030, Vienna, Austria; University of Vienna, Center for Molecular Biology, Department of Biochemistry and Cell Biology, Dr. Bohr-Gasse 9, 1030, Vienna, Austria.
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9
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Sheppard SE, Bryant L, Wickramasekara RN, Vaccaro C, Robertson B, Hallgren J, Hulen J, Watson CJ, Faundes V, Duffourd Y, Lee P, Simon MC, de la Cruz X, Padilla N, Flores-Mendez M, Akizu N, Smiler J, Pellegrino Da Silva R, Li D, March M, Diaz-Rosado A, Peixoto de Barcelos I, Choa ZX, Lim CY, Dubourg C, Journel H, Demurger F, Mulhern M, Akman C, Lippa N, Andrews M, Baldridge D, Constantino J, van Haeringen A, Snoeck-Streef I, Chow P, Hing A, Graham JM, Au M, Faivre L, Shen W, Mao R, Palumbos J, Viskochil D, Gahl W, Tifft C, Macnamara E, Hauser N, Miller R, Maffeo J, Afenjar A, Doummar D, Keren B, Arn P, Macklin-Mantia S, Meerschaut I, Callewaert B, Reis A, Zweier C, Brewer C, Saggar A, Smeland MF, Kumar A, Elmslie F, Deshpande C, Nizon M, Cogne B, van Ierland Y, Wilke M, van Slegtenhorst M, Koudijs S, Chen JY, Dredge D, Pier D, Wortmann S, Kamsteeg EJ, Koch J, Haynes D, Pollack L, Titheradge H, Ranguin K, Denommé-Pichon AS, Weber S, Pérez de la Fuente R, Sánchez del Pozo J, Lezana Rosales JM, Joset P, Steindl K, Rauch A, Mei D, Mari F, Guerrini R, Lespinasse J, Tran Mau-Them F, Philippe C, Dauriat B, Raymond L, Moutton S, Cueto-González AM, Tan TY, Mignot C, Grotto S, Renaldo F, Drivas TG, Hennessy L, Raper A, Parenti I, Kaiser FJ, Kuechler A, Busk ØL, Islam L, Siedlik JA, Henderson LB, Juusola J, Person R, Schnur RE, Vitobello A, Banka S, Bhoj EJ, Stessman HA. Mechanism of KMT5B haploinsufficiency in neurodevelopment in humans and mice. SCIENCE ADVANCES 2023; 9:eade1463. [PMID: 36897941 PMCID: PMC10005179 DOI: 10.1126/sciadv.ade1463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
Pathogenic variants in KMT5B, a lysine methyltransferase, are associated with global developmental delay, macrocephaly, autism, and congenital anomalies (OMIM# 617788). Given the relatively recent discovery of this disorder, it has not been fully characterized. Deep phenotyping of the largest (n = 43) patient cohort to date identified that hypotonia and congenital heart defects are prominent features that were previously not associated with this syndrome. Both missense variants and putative loss-of-function variants resulted in slow growth in patient-derived cell lines. KMT5B homozygous knockout mice were smaller in size than their wild-type littermates but did not have significantly smaller brains, suggesting relative macrocephaly, also noted as a prominent clinical feature. RNA sequencing of patient lymphoblasts and Kmt5b haploinsufficient mouse brains identified differentially expressed pathways associated with nervous system development and function including axon guidance signaling. Overall, we identified additional pathogenic variants and clinical features in KMT5B-related neurodevelopmental disorder and provide insights into the molecular mechanisms of the disorder using multiple model systems.
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Affiliation(s)
- Sarah E. Sheppard
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Unit on Vascular Malformations, Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Laura Bryant
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Rochelle N. Wickramasekara
- Stessman Laboratory, Department of Pharmacology and Neuroscience, Creighton University Medical School, Omaha, NE, USA
- Molecular Diagnostic Laboratory, Boys Town National Research Hospital, Omaha, NE, USA
| | - Courtney Vaccaro
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Brynn Robertson
- Stessman Laboratory, Department of Pharmacology and Neuroscience, Creighton University Medical School, Omaha, NE, USA
| | - Jodi Hallgren
- Stessman Laboratory, Department of Pharmacology and Neuroscience, Creighton University Medical School, Omaha, NE, USA
| | - Jason Hulen
- Stessman Laboratory, Department of Pharmacology and Neuroscience, Creighton University Medical School, Omaha, NE, USA
| | - Cynthia J. Watson
- Stessman Laboratory, Department of Pharmacology and Neuroscience, Creighton University Medical School, Omaha, NE, USA
| | - Victor Faundes
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Yannis Duffourd
- Unité Fonctionnelle d’Innovation diagnostique des maladies rares, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
| | - Pearl Lee
- Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - M. Celeste Simon
- Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Xavier de la Cruz
- Vall d’Hebron Institute of Research (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain
- Institució Catalana de Recerca I Estudis Avançats (ICREA), Barcelona, Spain
| | - Natália Padilla
- Vall d’Hebron Institute of Research (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Marco Flores-Mendez
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Naiara Akizu
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jacqueline Smiler
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- 10x Genomics, Pleasanton, CA, USA
| | | | - Dong Li
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Michael March
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Abdias Diaz-Rosado
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | | | - Zhao Xiang Choa
- Epithelial Epigenetics and Development Laboratory, A*STAR Skin Research Labs, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Chin Yan Lim
- Epithelial Epigenetics and Development Laboratory, A*STAR Skin Research Labs, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Christèle Dubourg
- Laboratoire de Génétique Moléculaire et Génomique, Centre Hospitalier Universitaire de Rennes, Rennes 35033, France
| | - Hubert Journel
- Service de Génétique Médicale, Hopital Chubert, Vannes, Bretagne, France
| | - Florence Demurger
- Department of Clinical Genetics, Service de Génétique Clinique, Centre de Référence Maladies Rares Centre Labellisé Anomalies du Développement-Ouest, Centre Hospitalier Universitaire de Rennes, Rennes 35033, France
| | - Maureen Mulhern
- Department of Pathology, Columbia University Irving Medical Center, New York, NY, USA
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
| | - Cigdem Akman
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
| | - Natalie Lippa
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | - Marisa Andrews
- Division of Genetics and Genomic Medicine, Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - Dustin Baldridge
- Division of Genetics and Genomic Medicine, Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - John Constantino
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
| | - Arie van Haeringen
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Irina Snoeck-Streef
- Department of Child Neurology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Penny Chow
- Department of Pediatrics, Division of Craniofacial Medicine, University of Washington, Seattle, WA, USA
| | - Anne Hing
- Department of Pediatrics, Division of Craniofacial Medicine, University of Washington, Seattle, WA, USA
| | - John M. Graham
- Medical Genetics, Department of Pediatrics, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, CA, USA
| | - Margaret Au
- Medical Genetics, Department of Pediatrics, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, CA, USA
| | - Laurence Faivre
- UFR Des Sciences de Santé, INSERM–Université de Bourgogne UMR1231 GAD “Génétique des Anomalies du Développement,” FHU-TRANSLAD, Dijon, France
- Centre de Référence Anomalies du Développement et Syndromes Malformatifs, CHU Dijon, Bourgogne, France
| | - Wei Shen
- University of Utah, Salt Lake City, UT, USA
- Mayo Clinic, Rochester, MN, USA
| | - Rong Mao
- University of Utah, Salt Lake City, UT, USA
| | | | | | - William Gahl
- NIH Undiagnosed Diseases Program, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Cynthia Tifft
- NIH Undiagnosed Diseases Program, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ellen Macnamara
- NIH Undiagnosed Diseases Program, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Natalie Hauser
- Medical Genetics, Inova Fairfax Hospital, Falls Church, VA, USA
| | - Rebecca Miller
- Medical Genetics, Inova Fairfax Hospital, Falls Church, VA, USA
| | - Jessica Maffeo
- Medical Genetics, Inova Fairfax Hospital, Falls Church, VA, USA
| | - Alexandra Afenjar
- AP-HP, Sorbonne Université, Département de neuropediatrie, Hospital Armand Trousseau, Paris, France
| | - Diane Doummar
- AP-HP, Sorbonne Université, Département de neuropediatrie, Hospital Armand Trousseau, Paris, France
| | - Boris Keren
- Genetic Department, Pitié-Salpêtrière Hospital, AP-HP, Sorbonne Université, Paris, France
| | - Pamela Arn
- Department of Pediatrics, Nemours Children’s Specialty Care, Jacksonville, FL, USA
| | | | - Ilse Meerschaut
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Bert Callewaert
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - André Reis
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Christiane Zweier
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
- Department of Human Genetics, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland
| | - Carole Brewer
- Clinical Genetics Department, Royal Devon and Exeter Hospital (Heavitree), Exeter EX1 2ED, UK
| | - Anand Saggar
- Clinical Genetics Department, St George’s Hospital, St George’s Healthcare NHS Trust, London SW17 0QT, UK
| | - Marie F. Smeland
- Department of Medical Genetics, University Hospital of North Norway, Tromsø, Norway
- Department of Pediatric Rehabilitation, University Hospital of North Norway, Norway
| | - Ajith Kumar
- Northeast Thames Regional Genetics Service, Great Ormond Street Hospital, London WC1N 3JH, UK
| | - Frances Elmslie
- South West Thames Centre for Genomics, St George’s University Hospitals NHS Foundation Trust, London SW17 0QT, UK
| | - Charu Deshpande
- Department of Medical Genetics, Guy’s Hospital, London SE1 9RT, UK
| | - Mathilde Nizon
- CHU Nantes, Service de Génétique Médicale, 9 quai Moncousu, 44093 Nantes CEDEX 1, France
| | - Benjamin Cogne
- CHU Nantes, Service de Génétique Médicale, 9 quai Moncousu, 44093 Nantes CEDEX 1, France
- Nantes Université, CNRS, INSERM, L’institut du thorax, F-44000 Nantes, France
| | - Yvette van Ierland
- Department of Clinical Genetics, Erasmus University Medical Center, P.O. Box 2040, 3000 CA Rotterdam, Netherlands
| | - Martina Wilke
- Department of Clinical Genetics, Erasmus University Medical Center, P.O. Box 2040, 3000 CA Rotterdam, Netherlands
| | - Marjon van Slegtenhorst
- Department of Clinical Genetics, Erasmus University Medical Center, P.O. Box 2040, 3000 CA Rotterdam, Netherlands
| | - Suzanne Koudijs
- Department of Neurology, Erasmus University Medical Center–Sophia Children’s Hospital, P.O. Box 2040, 3000 CA Rotterdam, Netherlands
| | - Jin Yun Chen
- Neurology Department, Massachusetts General Hospital, Boston, MA, USA
| | - David Dredge
- University Children’s Hospital Salzburg, Paracelsus Medical University (PMU), Salzburg, Austria
| | - Danielle Pier
- Neurology Department, Massachusetts General Hospital, Boston, MA, USA
| | - Saskia Wortmann
- University Children’s Hospital Salzburg, Paracelsus Medical University (PMU), Salzburg, Austria
- Amalia Children’s Hospital, RadboudUMC Nijmegen, Nijmegen, Netherlands
| | - Erik-Jan Kamsteeg
- University Children’s Hospital Salzburg, Paracelsus Medical University (PMU), Salzburg, Austria
| | - Johannes Koch
- University Children’s Hospital Salzburg, Paracelsus Medical University (PMU), Salzburg, Austria
| | - Devon Haynes
- Division of Genetics, Arnold Palmer Hospital for Children–Orlando Health, Orlando, FL, USA
| | - Lynda Pollack
- Division of Genetics, Arnold Palmer Hospital for Children–Orlando Health, Orlando, FL, USA
| | - Hannah Titheradge
- West Midlands Regional Genetics Service and Birmingham Health Partners, Birmingham Women’s and Children’s NHS Trust, Birmingham B15 2TG, UK
| | - Kara Ranguin
- Department of Genetics, Reference Centre for Rare Diseases and Developmental Anomalies, Caen Hospital, Caen, France
| | - Anne-Sophie Denommé-Pichon
- Unité Fonctionnelle d’Innovation diagnostique des maladies rares, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
- UFR Des Sciences de Santé, INSERM–Université de Bourgogne UMR1231 GAD “Génétique des Anomalies du Développement,” FHU-TRANSLAD, Dijon, France
| | - Sacha Weber
- Department of Genetics, Reference Centre for Rare Diseases and Developmental Anomalies, Caen Hospital, Caen, France
| | | | - Jaime Sánchez del Pozo
- UDISGEN (Unidad de Dismorfología y Genética) 12 de Octubre University Hospital, Madrid, Spain
| | | | - Pascal Joset
- University of Zurich, Institute of Medical Genetics, 8952 Schlieren-Zurich, Switzerland
| | - Katharina Steindl
- University of Zurich, Institute of Medical Genetics, 8952 Schlieren-Zurich, Switzerland
| | - Anita Rauch
- University of Zurich, Institute of Medical Genetics, 8952 Schlieren-Zurich, Switzerland
- University of Zurich, University Children’s Hospital Zurich, 8032 Zurich, Switzerland
- University of Zurich, URPP Adaptive Brain Circuits in Development and Learning (AdaBD), Zurich, Switzerland
- University of Zurich Research Priority Program (URPP) AdaBD: Adaptive Brain Circuits in Development and Learning, Zurich 8006, Switzerland
- University of Zurich Research Priority Program (URPP) ITINERARE: Innovative Therapies in Rare Diseases, Zurich 8006, Switzerland
| | - Davide Mei
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Meyer Children’s Hospital, Member of ERN Epicare, University of Florence, Florence, Italy
| | - Francesco Mari
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Meyer Children’s Hospital, Member of ERN Epicare, University of Florence, Florence, Italy
| | - Renzo Guerrini
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Meyer Children’s Hospital, Member of ERN Epicare, University of Florence, Florence, Italy
| | - James Lespinasse
- UF de Génétique Chromosomique, Centre Hospitalier de Chambéry, Hôtel-dieu, France
| | - Frédéric Tran Mau-Them
- Unité Fonctionnelle d’Innovation diagnostique des maladies rares, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
- UFR Des Sciences de Santé, INSERM–Université de Bourgogne UMR1231 GAD “Génétique des Anomalies du Développement,” FHU-TRANSLAD, Dijon, France
| | - Christophe Philippe
- Unité Fonctionnelle d’Innovation diagnostique des maladies rares, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
- UFR Des Sciences de Santé, INSERM–Université de Bourgogne UMR1231 GAD “Génétique des Anomalies du Développement,” FHU-TRANSLAD, Dijon, France
| | - Benjamin Dauriat
- Service de cytogénétique et génétique médicale, Centre Hospitalier Universitaire de Limoges, France
| | - Laure Raymond
- Service de génétique, Laboratoire Eurofins Biomnis, Lyon, France
| | | | - Anna M. Cueto-González
- Hospital Vall d'Hebron, Barcelona, Spain
- Department of Clinical and Molecular Genetics, Vall d'Hebron Barcelona Hospital Campus, Passeig Vall d'Hebron 119-129, 08035 Barcelona, Spain
| | - Tiong Yang Tan
- Victorian Clinical Genetics Services, Murdoch Children’s Research Institute, Melbourne, VIC, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, VIC, Australia
| | - Cyril Mignot
- AP-HP, Sorbonne Université, Département de Génétique, Paris, France
| | - Sarah Grotto
- AP-HP, Sorbonne Université, Département de Génétique, Paris, France
| | - Florence Renaldo
- AP-HP, Sorbonne Université, Département de neuropediatrie, Centre de référence neurogénétique, Hôpital Armand Trousseau, Paris, France
| | - Theodore G. Drivas
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Laura Hennessy
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Anna Raper
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Ilaria Parenti
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Frank J. Kaiser
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
- Essener Zentrum für Seltene Erkrankungen (EZSE), Universitätsklinikum Essen, Essen, Germany
| | - Alma Kuechler
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Øyvind L. Busk
- Department of Medical Genetics, Telemark Hospital Trust, 3710 Skien, Norway
| | - Lily Islam
- West Midlands Regional Genetics Service and Birmingham Health Partners, Birmingham Women’s and Children’s NHS Trust, Birmingham B15 2TG, UK
| | - Jacob A. Siedlik
- Department of Exercise Science and Pre-Health Professions, Creighton University, Omaha, NE, USA
| | | | | | | | - Rhonda E. Schnur
- GeneDx, Gaithersburg, MD, USA
- Department of Pediatrics, Division of Genetics Cooper Medical School of Rowan University Cooper University Health Care 3, Cooper Plaza, Camden, NJ, USA
| | - Antonio Vitobello
- Unité Fonctionnelle d’Innovation diagnostique des maladies rares, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
- UFR Des Sciences de Santé, INSERM–Université de Bourgogne UMR1231 GAD “Génétique des Anomalies du Développement,” FHU-TRANSLAD, Dijon, France
| | - Siddharth Banka
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Elizabeth J. Bhoj
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Holly A. F. Stessman
- Stessman Laboratory, Department of Pharmacology and Neuroscience, Creighton University Medical School, Omaha, NE, USA
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10
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Thole JF, Waudby CA, Pielak GJ. Disordered proteins mitigate the temperature dependence of site-specific binding free energies. J Biol Chem 2023; 299:102984. [PMID: 36739945 PMCID: PMC10027511 DOI: 10.1016/j.jbc.2023.102984] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 01/12/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023] Open
Abstract
Biophysical characterization of protein-protein interactions involving disordered proteins is challenging. A common simplification is to measure the thermodynamics and kinetics of disordered site binding using peptides containing only the minimum residues necessary. We should not assume, however, that these few residues tell the whole story. Son of sevenless, a multidomain signaling protein from Drosophila melanogaster, is critical to the mitogen-activated protein kinase pathway, passing an external signal to Ras, which leads to cellular responses. The disordered 55 kDa C-terminal domain of Son of sevenless is an autoinhibitor that blocks guanidine exchange factor activity. Activation requires another protein, Downstream of receptor kinase (Drk), which contains two Src homology 3 domains. Here, we utilized NMR spectroscopy and isothermal titration calorimetry to quantify the thermodynamics and kinetics of the N-terminal Src homology 3 domain binding to the strongest sites incorporated into the flanking disordered sequences. Comparing these results to those for isolated peptides provides information about how the larger domain affects binding. The affinities of sites on the disordered domain are like those of the peptides at low temperatures but less sensitive to temperature. Our results, combined with observations showing that intrinsically disordered proteins become more compact with increasing temperature, suggest a mechanism for this effect.
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Affiliation(s)
- Joseph F Thole
- Department of Chemistry, UNC-Chapel Hill, Chapel Hill, North Carolina, USA; Molecular and Cellular Biophysics Program, UNC-Chapel Hill, Chapel Hill, North Carolina, USA
| | | | - Gary J Pielak
- Department of Chemistry, UNC-Chapel Hill, Chapel Hill, North Carolina, USA; Molecular and Cellular Biophysics Program, UNC-Chapel Hill, Chapel Hill, North Carolina, USA; Department of Biochemistry & Biophysics, UNC-Chapel Hill, Chapel Hill, North Carolina, USA; Lineberger Cancer Center, UNC-Chapel Hill, Chapel Hill, North Carolina, USA; Integrative Program for Biological and Genome Sciences, UNC - Chapel Hill, Chapel Hill, North Carolina, USA.
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11
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Ni Q, Zhu B, Ji Y, Zheng Q, Liang X, Ma N, Jiang H, Zhang F, Shang Y, Wang Y, Xu S, Zhang E, Yuan Y, Chen T, Yin F, Cao H, Huang J, Xia J, Ding X, Qiu X, Ding K, Song C, Zhou W, Wu M, Wang K, Lui R, Lin Q, Chen W, Li Z, Cheng S, Wang X, Xie D, Li J. PPDPF Promotes the Development of Mutant KRAS-Driven Pancreatic Ductal Adenocarcinoma by Regulating the GEF Activity of SOS1. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2202448. [PMID: 36453576 PMCID: PMC9839844 DOI: 10.1002/advs.202202448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 10/11/2022] [Indexed: 06/17/2023]
Abstract
The guanine nucleotide exchange factor (GEF) SOS1 catalyzes the exchange of GDP for GTP on RAS. However, regulation of the GEF activity remains elusive. Here, the authors report that PPDPF functions as an important regulator of SOS1. The expression of PPDPF is significantly increased in pancreatic ductal adenocarcinoma (PDAC), associated with poor prognosis and recurrence of PDAC patients. Overexpression of PPDPF promotes PDAC cell growth in vitro and in vivo, while PPDPF knockout exerts opposite effects. Pancreatic-specific deletion of PPDPF profoundly inhibits tumor development in KRASG12D -driven genetic mouse models of PDAC. PPDPF can bind GTP and transfer GTP to SOS1. Mutations of the GTP-binding sites severely impair the tumor-promoting effect of PPDPF. Consistently, mutations of the critical amino acids mediating SOS1-PPDPF interaction significantly impair the GEF activity of SOS1. Therefore, this study demonstrates a novel model of KRAS activation via PPDPF-SOS1 axis, and provides a promising therapeutic target for PDAC.
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12
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Mercadante F, Piro E, Busè M, Salzano E, Ferrara A, Serra G, Passarello C, Corsello G, Piccione M. Cutis verticis gyrata and Noonan syndrome: report of two cases with pathogenetic variant in SOS1 gene. Ital J Pediatr 2022; 48:152. [PMID: 35986401 PMCID: PMC9392323 DOI: 10.1186/s13052-022-01340-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/08/2022] [Indexed: 11/22/2022] Open
Abstract
Background Noonan and Noonan-like syndromes are multisystem genetic disorders, mainly with autosomal dominant trasmission, caused by mutations in several genes. Missense pathogenetic variants of SOS1 gene are the second most common cause of Noonan syndrome (NS) and account approximately for 13% to 17% of cases. Subjects carrying a pathogenetic variant in SOS1 gene tend to exhibit a distinctive phenotype that is characterized by ectodermal abnormalities. Cutis verticis gyrata (CVG) is a rare disease, congenital or acquired, characterized by the redundancy of skin on scalp, forming thick skin folds and grooves of similar aspect to cerebral cortex gyri. Several references in the literature have reported association between nonessential primary form of CVG and NS. Case presentation we report two cases of newborns with CVG and phenotype suggestive for NS who have been diagnosed to harbour the same pathogenetic variant in SOS1 gene. Conclusions previously described patients with NS presenting CVG had received only clinical diagnosis. Therefore we report the first patients with CVG in which the clinical suspicion of NS is confirmed by molecolar analysis.
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Eves BJ, Gebregiworgis T, Gasmi-Seabrook GM, Kuntz DA, Privé GG, Marshall CB, Ikura M. Structures of RGL1 RAS-Association domain in complex with KRAS and the oncogenic G12V mutant. J Mol Biol 2022; 434:167527. [DOI: 10.1016/j.jmb.2022.167527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 02/24/2022] [Accepted: 03/01/2022] [Indexed: 11/28/2022]
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Abstract
RAS proteins play major roles in many human cancers, but programs to develop direct RAS inhibitors so far have only been successful for the oncogenic KRAS mutant G12C. As an alternative approach, inhibitors for the RAS guanine nucleotide exchange factor SOS1 have been investigated by several academic groups and companies, and major progress has been achieved in recent years in the optimization of small molecule activators and inhibitors of SOS1. Here, we review the discovery and development of small molecule modulators of SOS1 and their molecular binding modes and modes of action. As targeting the RAS pathway is expected to result in the development of resistance mechanisms, SOS1 inhibitors will most likely be best applied in vertical combination approaches where two nodes of the RAS signaling pathway are hit simultaneously. We summarize the current understanding of which combination partners may be most beneficial for patients with RAS driven tumors.
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Affiliation(s)
| | - Benjamin Bader
- Screening, Lead Discovery, Nuvisan ICB GmbH, Berlin, Germany
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15
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Abstract
The RASopathies are a group of disorders caused by a germline mutation in one of the genes encoding a component of the RAS/MAPK pathway. These disorders, including neurofibromatosis type 1, Noonan syndrome, cardiofaciocutaneous syndrome, Costello syndrome and Legius syndrome, among others, have overlapping clinical features due to RAS/MAPK dysfunction. Although several of the RASopathies are very rare, collectively, these disorders are relatively common. In this Review, we discuss the pathogenesis of the RASopathy-associated genetic variants and the knowledge gained about RAS/MAPK signaling that resulted from studying RASopathies. We also describe the cell and animal models of the RASopathies and explore emerging RASopathy genes. Preclinical and clinical experiences with targeted agents as therapeutics for RASopathies are also discussed. Finally, we review how the recently developed drugs targeting RAS/MAPK-driven malignancies, such as inhibitors of RAS activation, direct RAS inhibitors and RAS/MAPK pathway inhibitors, might be leveraged for patients with RASopathies.
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Affiliation(s)
- Katie E Hebron
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Edjay Ralph Hernandez
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Marielle E Yohe
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
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16
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Sigamani V, Rajasingh S, Gurusamy N, Panda A, Rajasingh J. In-Silico and In-Vitro Analysis of Human SOS1 Protein Causing Noonan Syndrome - A Novel Approach to Explore the Molecular Pathways. Curr Genomics 2021; 22:526-540. [PMID: 35386434 PMCID: PMC8905634 DOI: 10.2174/1389202922666211130144221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 11/22/2022] Open
Abstract
Aims Perform in-silico analysis of human SOS1 mutations to elucidate their pathogenic role in Noonan syndrome (NS). Background NS is an autosomal dominant genetic disorder caused by single nucleotide mutation in PTPN11, SOS1, RAF1, and KRAS genes. NS is thought to affect approximately 1 in 1000. NS patients suffer different pathogenic effects depending on the mutations they carry. Analysis of the mutations would be a promising predictor in identifying the pathogenic effect of NS. Methods We performed computational analysis of the SOS1 gene to identify the pathogenic nonsynonymous single nucleotide polymorphisms (nsSNPs) th a t cause NS. SOS1 variants were retrieved from the SNP database (dbSNP) and analyzed by in-silico tools I-Mutant, iPTREESTAB, and MutPred to elucidate their structural and functional characteristics. Results We found that 11 nsSNPs of SOS1 that were linked to NS. 3D modeling of the wild-type and the 11 nsSNPs of SOS1 showed that SOS1 interacts with cardiac proteins GATA4, TNNT2, and ACTN2. We also found that GRB2 and HRAS act as intermediate molecules between SOS1 and cardiac proteins. Our in-silico analysis findings were further validated using induced cardiomyocytes (iCMCs) derived from NS patients carrying SOS1 gene variant c.1654A>G (NSiCMCs) and compared to control human skin fibroblast-derived iCMCs (C-iCMCs). Our in vitro data confirmed that the SOS1, GRB2 and HRAS gene expressions as well as the activated ERK protein, were significantly decreased in NS-iCMCs when compared to C-iCMCs. Conclusion This is the first in-silico and in vitro study demonstrating that 11 nsSNPs of SOS1 play deleterious pathogenic roles in causing NS.
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Affiliation(s)
- Vinoth Sigamani
- Department of Bioscience Research, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Sheeja Rajasingh
- Department of Bioscience Research, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Narasimman Gurusamy
- Department of Bioscience Research, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Arunima Panda
- Department of Genetic Engineering, SRM Institute of Science and Technology, Chennai, India
| | - Johnson Rajasingh
- Department of Bioscience Research, University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Medicine-Cardiology, University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Microbiology, Immunology & Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee
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Huang WYC, Alvarez S, Kondo Y, Kuriyan J, Groves JT. Relating cellular signaling timescales to single-molecule kinetics: A first-passage time analysis of Ras activation by SOS. Proc Natl Acad Sci U S A 2021; 118:e2103598118. [PMID: 34740968 PMCID: PMC8694064 DOI: 10.1073/pnas.2103598118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2021] [Indexed: 12/27/2022] Open
Abstract
Son of Sevenless (SOS) is a Ras guanine nucleotide exchange factor (GEF) that plays a central role in numerous cellular signaling pathways. Like many other signaling molecules, SOS is autoinhibited in the cytosol and activates only after recruitment to the membrane. The mean activation time of individual SOS molecules has recently been measured to be ∼60 s, which is unexpectedly long and seemingly contradictory with cellular signaling timescales, which have been measured to be as fast as several seconds. Here, we rectify this discrepancy using a first-passage time analysis to reconstruct the effective signaling timescale of multiple SOS molecules from their single-molecule activation kinetics. Along with corresponding experimental measurements, this analysis reveals how the functional response time, comprised of many slowly activating molecules, can become substantially faster than the average molecular kinetics. This consequence stems from the enzymatic processivity of SOS in a highly out-of-equilibrium reaction cycle during receptor triggering. Ultimately, rare, early activation events dominate the macroscopic reaction dynamics.
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Affiliation(s)
- William Y C Huang
- Department of Chemistry, University of California, Berkeley, CA 94720
| | - Steven Alvarez
- Department of Materials Science and Engineering, University of California, Berkeley, CA 94720
| | - Yasushi Kondo
- Department of Chemistry, University of California, Berkeley, CA 94720
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720
| | - John Kuriyan
- Department of Chemistry, University of California, Berkeley, CA 94720
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720
- HHMI, University of California, Berkeley, CA 94720
- Division of Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Jay T Groves
- Department of Chemistry, University of California, Berkeley, CA 94720;
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720
- Division of Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
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18
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Regulation of the Small GTPase Ras and Its Relevance to Human Disease. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2021; 2262:19-43. [PMID: 33977469 DOI: 10.1007/978-1-0716-1190-6_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ras research has experienced a considerable boost in recent years, not least prompted by the Ras initiative launched by the NCI in 2013 ( https://www.cancer.gov/research/key-initiatives/ras ), accompanied and conditioned by a strongly reinvigorated determination within the Ras community to develop therapeutics attacking directly the Ras oncoproteins. As a member of the small G-protein superfamily, function and transforming activity of Ras all revolve about its GDP/GTP loading status. For one thing, the extent of GTP loading will determine the proportion of active Ras in the cell, with implications for intensity and quality of downstream signaling. But also the rate of nucleotide exchange, i.e., the Ras-GDP/GTP cycling rate, can have a major impact on Ras function, as illustrated perhaps most impressively by newly discovered fast-cycling oncogenic mutants of the Ras-related GTPase Rac1. Thus, while the last years have witnessed memorable new findings and technical developments in the Ras field, leading to an improved insight into many aspects of Ras biology, they have not jolted at the basics, but rather deepened our view of the fundamental regulatory principles of Ras activity control. In this brief review, we revisit the role and mechanisms of Ras nucleotide loading and its implications for cancer in the light of recent findings.
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19
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Kessler D, Gerlach D, Kraut N, McConnell DB. Targeting Son of Sevenless 1: The pacemaker of KRAS. Curr Opin Chem Biol 2021; 62:109-118. [PMID: 33848766 DOI: 10.1016/j.cbpa.2021.02.014] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 02/23/2021] [Accepted: 02/27/2021] [Indexed: 12/12/2022]
Abstract
Son of Sevenless (SOS) is a guanine nucleotide exchange factor that activates the important cell signaling switch KRAS. SOS acts as a pacemaker for KRAS, the beating heart of cancer, by catalyzing the "beating" from the KRAS(off) to the KRAS(on) conformation. Activating mutations in SOS1 are common in Noonan syndrome and oncogenic alterations in KRAS drive 1 in seven human cancers. Promising clinical efficacy has been observed for selective KRASG12C inhibitors, but the vast majority of oncogenic KRAS alterations remain undrugged. The discovery of a druggable pocket on SOS1 has led to potent SOS1 inhibitors such as BI-3406. SOS1 inhibition leads to antiproliferative effects against all major KRAS mutants. The first SOS1 inhibitor has entered clinical trials for KRAS-mutated cancers. In this review, we provide an overview of SOS1 function, its association with cancer and RASopathies, known SOS1 activators and inhibitors, and a future perspective is provided.
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Affiliation(s)
- Dirk Kessler
- Discovery Research, Boehringer Ingelheim Regional Center Vienna GmbH & Co KG, 1120, Vienna, Austria
| | - Daniel Gerlach
- Discovery Research, Boehringer Ingelheim Regional Center Vienna GmbH & Co KG, 1120, Vienna, Austria
| | - Norbert Kraut
- Discovery Research, Boehringer Ingelheim Regional Center Vienna GmbH & Co KG, 1120, Vienna, Austria
| | - Darryl B McConnell
- Discovery Research, Boehringer Ingelheim Regional Center Vienna GmbH & Co KG, 1120, Vienna, Austria.
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20
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Botterbusch S, Baumgart T. Interactions between Phase-Separated Liquids and Membrane Surfaces. APPLIED SCIENCES (BASEL, SWITZERLAND) 2021; 11:1288. [PMID: 34327010 PMCID: PMC8315427 DOI: 10.3390/app11031288] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Liquid-liquid phase separation has recently emerged as an important fundamental organizational phenomenon in biological settings. Most studies of biological phase separation have focused on droplets that "condense" from solution above a critical concentration, forming so-called "membraneless organelles" suspended in solution. However, membranes are ubiquitous throughout cells, and many biomolecular condensates interact with membrane surfaces. Such membrane-associated phase-separated systems range from clusters of integral or peripheral membrane proteins in the plane of the membrane to free, spherical droplets wetting membrane surfaces to droplets containing small lipid vesicles. In this review, we consider phase-separated liquids that interact with membrane surfaces and we discuss the consequences of those interactions. The physical properties of distinct liquid phases in contact with bilayers can reshape the membrane, and liquid-liquid phase separation can construct membrane-associated protein structures, modulate their function, and organize collections of lipid vesicles dynamically. We summarize the common phenomena that arise in these systems of liquid phases and membranes.
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21
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Membrane therapy using DHA suppresses epidermal growth factor receptor signaling by disrupting nanocluster formation. J Lipid Res 2021; 62:100026. [PMID: 33515553 PMCID: PMC7933808 DOI: 10.1016/j.jlr.2021.100026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 01/11/2021] [Accepted: 01/19/2021] [Indexed: 02/07/2023] Open
Abstract
Epidermal growth factor receptor (EGFR) signaling drives the formation of many types of cancer, including colon cancer. Docosahexaenoic acid (DHA, 22∶6Δ4,7,10,13,16,19), a chemoprotective long-chain n-3 polyunsaturated fatty acid suppresses EGFR signaling. However, the mechanism underlying this phenotype remains unclear. Therefore, we used super-resolution microscopy techniques to investigate the mechanistic link between EGFR function and DHA-induced alterations to plasma membrane nanodomains. Using isogenic in vitro (YAMC and IMCE mouse colonic cell lines) and in vivo (Drosophila, wild type and Fat-1 mice) models, cellular DHA enrichment via therapeutic nanoparticle delivery, endogenous synthesis, or dietary supplementation reduced EGFR-mediated cell proliferation and downstream Ras/ERK signaling. Phospholipid incorporation of DHA reduced membrane rigidity and the size of EGFR nanoclusters. Similarly, pharmacological reduction of plasma membrane phosphatidic acid (PA), phosphatidylinositol-4,5-bisphosphate (PIP2) or cholesterol was associated with a decrease in EGFR nanocluster size. Furthermore, in DHA-treated cells only the addition of cholesterol, unlike PA or PIP2, restored EGFR nanoscale clustering. These findings reveal that DHA reduces EGFR signaling in part by reshaping EGFR proteolipid nanodomains, supporting the feasibility of using membrane therapy, i.e., dietary/drug-related strategies to target plasma membrane organization, to reduce EGFR signaling and cancer risk.
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22
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Natural Products Attenuating Biosynthesis, Processing, and Activity of Ras Oncoproteins: State of the Art and Future Perspectives. Biomolecules 2020; 10:biom10111535. [PMID: 33182807 PMCID: PMC7698260 DOI: 10.3390/biom10111535] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/03/2020] [Accepted: 11/08/2020] [Indexed: 02/07/2023] Open
Abstract
RAS genes encode signaling proteins, which, in mammalian cells, act as molecular switches regulating critical cellular processes as proliferation, growth, differentiation, survival, motility, and metabolism in response to specific stimuli. Deregulation of Ras functions has a high impact on human health: gain-of-function point mutations in RAS genes are found in some developmental disorders and thirty percent of all human cancers, including the deadliest. For this reason, the pathogenic Ras variants represent important clinical targets against which to develop novel, effective, and possibly selective pharmacological inhibitors. Natural products represent a virtually unlimited resource of structurally different compounds from which one could draw on for this purpose, given the improvements in isolation and screening of active molecules from complex sources. After a summary of Ras proteins molecular and regulatory features and Ras-dependent pathways relevant for drug development, we point out the most promising inhibitory approaches, the known druggable sites of wild-type and oncogenic Ras mutants, and describe the known natural compounds capable of attenuating Ras signaling. Finally, we highlight critical issues and perspectives for the future selection of potential Ras inhibitors from natural sources.
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23
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The hanging heart: How KRAS lures its prey to the membrane. Proc Natl Acad Sci U S A 2020; 117:26556-26558. [PMID: 32999064 DOI: 10.1073/pnas.2017730117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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24
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Baltanás FC, Zarich N, Rojas-Cabañeros JM, Santos E. SOS GEFs in health and disease. Biochim Biophys Acta Rev Cancer 2020; 1874:188445. [PMID: 33035641 DOI: 10.1016/j.bbcan.2020.188445] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/01/2020] [Accepted: 10/01/2020] [Indexed: 12/11/2022]
Abstract
SOS1 and SOS2 are the most universal and widely expressed family of guanine exchange factors (GEFs) capable or activating RAS or RAC1 proteins in metazoan cells. SOS proteins contain a sequence of modular domains that are responsible for different intramolecular and intermolecular interactions modulating mechanisms of self-inhibition, allosteric activation and intracellular homeostasis. Despite their homology, analyses of SOS1/2-KO mice demonstrate functional prevalence of SOS1 over SOS2 in cellular processes including proliferation, migration, inflammation or maintenance of intracellular redox homeostasis, although some functional redundancy cannot be excluded, particularly at the organismal level. Specific SOS1 gain-of-function mutations have been identified in inherited RASopathies and various sporadic human cancers. SOS1 depletion reduces tumorigenesis mediated by RAS or RAC1 in mouse models and is associated with increased intracellular oxidative stress and mitochondrial dysfunction. Since WT RAS is essential for development of RAS-mutant tumors, the SOS GEFs may be considered as relevant biomarkers or therapy targets in RAS-dependent cancers. Inhibitors blocking SOS expression, intrinsic GEF activity, or productive SOS protein-protein interactions with cellular regulators and/or RAS/RAC targets have been recently developed and shown preclinical and clinical effectiveness blocking aberrant RAS signaling in RAS-driven and RTK-driven tumors.
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Affiliation(s)
- Fernando C Baltanás
- Centro de Investigación del Cáncer - IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Natasha Zarich
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Jose M Rojas-Cabañeros
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Eugenio Santos
- Centro de Investigación del Cáncer - IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007 Salamanca, Spain.
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25
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Carabias A, Gómez-Hernández M, de Cima S, Rodríguez-Blázquez A, Morán-Vaquero A, González-Sáenz P, Guerrero C, de Pereda JM. Mechanisms of autoregulation of C3G, activator of the GTPase Rap1, and its catalytic deregulation in lymphomas. Sci Signal 2020; 13:13/647/eabb7075. [PMID: 32873726 DOI: 10.1126/scisignal.abb7075] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
C3G is a guanine nucleotide exchange factor (GEF) that regulates cell adhesion and migration by activating the GTPase Rap1. The GEF activity of C3G is stimulated by the adaptor proteins Crk and CrkL and by tyrosine phosphorylation. Here, we uncovered mechanisms of C3G autoinhibition and activation. Specifically, we found that two intramolecular interactions regulate the activity of C3G. First, an autoinhibitory region (AIR) within the central domain of C3G binds to and blocks the catalytic Cdc25H domain. Second, the binding of the protein's N-terminal domain to its Ras exchanger motif (REM) is required for its GEF activity. CrkL activated C3G by displacing the AIR/Cdc25HD interaction. Two missense mutations in the AIR found in non-Hodgkin's lymphomas, Y554H and M555K, disrupted the autoinhibitory mechanism. Expression of C3G-Y554H or C3G-M555K in Ba/F3 pro-B cells caused constitutive activation of Rap1 and, consequently, the integrin LFA-1. Our findings suggest that sustained Rap1 activation by deregulated C3G might promote progression of lymphomas and that designing therapeutics to target C3G might treat these malignancies.
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Affiliation(s)
- Arturo Carabias
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, 37007 Salamanca, Spain
| | - María Gómez-Hernández
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, 37007 Salamanca, Spain
| | - Sergio de Cima
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, 37007 Salamanca, Spain
| | - Antonio Rodríguez-Blázquez
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, 37007 Salamanca, Spain
| | - Alba Morán-Vaquero
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, 37007 Salamanca, Spain
| | - Patricia González-Sáenz
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, 37007 Salamanca, Spain
| | - Carmen Guerrero
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, 37007 Salamanca, Spain.,Departamento de Medicina, Facultad de Medicina, Universidad de Salamanca, Instituto de Investigación Biomédica de Salamanca (IBSAL), 37007 Salamanca, Spain
| | - José M de Pereda
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, 37007 Salamanca, Spain.
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26
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Sun Z, Zhang H, Zhang Y, Liao L, Zhou W, Zhang F, Lian F, Huang J, Xu P, Zhang R, Lu W, Zhu M, Tao H, Yang F, Ding H, Chen S, Yue L, Zhou B, Zhang N, Tan M, Jiang H, Chen K, Liu B, Liu C, Dang Y, Luo C. Covalent Inhibitors Allosterically Block the Activation of Rho Family Proteins and Suppress Cancer Cell Invasion. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2000098. [PMID: 32714746 PMCID: PMC7375240 DOI: 10.1002/advs.202000098] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 03/27/2020] [Indexed: 05/31/2023]
Abstract
The Rho family GTPases are crucial drivers of tumor growth and metastasis. However, it is difficult to develop GTPases inhibitors due to a lack of well-characterized binding pockets for compounds. Here, through molecular dynamics simulation of the RhoA protein, a groove around cysteine 107 (Cys107) that is relatively well-conserved within the Rho family is discovered. Using a combined strategy, the novel inhibitor DC-Rhoin is discovered, which disrupts interaction of Rho proteins with guanine nucleotide exchange factors (GEFs) and guanine nucleotide dissociation inhibitors (GDIs). Crystallographic studies reveal that the covalent binding of DC-Rhoin to the Cys107 residue stabilizes and captures a novel allosteric pocket. Moreover, the derivative compound DC-Rhoin04 inhibits the migration and invasion of cancer cells, through targeting this allosteric pocket of RhoA. The study reveals a novel allosteric regulatory site within the Rho family, which can be exploited for anti-metastasis drug development, and also provides a novel strategy for inhibitor discovery toward "undruggable" protein targets.
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27
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Cowan JR, Salyer L, Wright NT, Kinnamon DD, Amaya P, Jordan E, Bamshad MJ, Nickerson DA, Hershberger RE. SOS1 Gain-of-Function Variants in Dilated Cardiomyopathy. CIRCULATION-GENOMIC AND PRECISION MEDICINE 2020; 13:e002892. [PMID: 32603605 DOI: 10.1161/circgen.119.002892] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Dilated cardiomyopathy (DCM) is a genetically heterogeneous cardiac disease characterized by progressive ventricular enlargement and reduced systolic function. Here, we report genetic and functional analyses implicating the rat sarcoma signaling protein, SOS1 (Son of sevenless homolog 1), in DCM pathogenesis. METHODS Exome sequencing was performed on 412 probands and family members from our DCM cohort, identifying several SOS1 variants with potential disease involvement. As several lines of evidence have implicated dysregulated rat sarcoma signaling in the pathogenesis of DCM, we assessed functional impact of each variant on the activation of ERK (extracellular signal-regulated kinase), AKT (protein kinase B), and JNK (c-Jun N-terminal kinase) pathways. Relative expression levels were determined by Western blot in HEK293T cells transfected with variant or wild-type human SOS1 expression constructs. RESULTS A rare SOS1 variant [c.571G>A, p.(Glu191Lys)] was found to segregate alongside an A-band TTN truncating variant in a pedigree with aggressive, early-onset DCM. Reduced disease severity in the absence of the SOS1 variant suggested its potential involvement as a genetic risk factor for DCM in this family. Exome sequencing identified 5 additional SOS1 variants with potential disease involvement in 4 other families [c.1820T>C, p.(Ile607Thr); c.2156G>C, p.(Gly719Ala); c.2230A>G, p.(Arg744Gly); c.2728G>C, p.(Asp910His); c.3601C>T, p.(Arg1201Trp)]. Impacted amino acids occupied a number of functional domains relevant to SOS1 activity, including the N-terminal histone fold, as well as the C-terminal REM (rat sarcoma exchange motif), CDC25 (cell division cycle 25), and PR (proline-rich) tail domains. Increased phosphorylated ERK expression relative to wild-type levels was seen for all 6 SOS1 variants, paralleling known disease-relevant SOS1 signaling profiles. CONCLUSIONS These data support gain-of-function variation in SOS1 as a contributing factor to isolated DCM.
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Affiliation(s)
- Jason R Cowan
- Dorothy M. Davis Heart and Lung Research Institute (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus.,Division of Human Genetics (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus
| | - Lorien Salyer
- Dorothy M. Davis Heart and Lung Research Institute (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus.,Division of Human Genetics (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus
| | - Nathan T Wright
- Department of Chemistry and Biochemistry, James Madison University, Harrisonburg, VA (N.T.W.)
| | - Daniel D Kinnamon
- Dorothy M. Davis Heart and Lung Research Institute (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus.,Division of Human Genetics (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus
| | - Pedro Amaya
- Dorothy M. Davis Heart and Lung Research Institute (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus.,Division of Human Genetics (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus
| | - Elizabeth Jordan
- Dorothy M. Davis Heart and Lung Research Institute (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus.,Division of Human Genetics (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus
| | - Michael J Bamshad
- Department of Pediatrics (M.J.B.), University of Washington, Seattle
| | | | - Ray E Hershberger
- Dorothy M. Davis Heart and Lung Research Institute (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus.,Division of Human Genetics (J.R.C., L.S., D.D.K., P.A., E.J., R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus.,Division of Cardiovascular Medicine (R.E.H.), Department of Internal Medicine, The Ohio State University College of Medicine, Columbus
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28
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Abstract
Many critical biological events, including biochemical signaling, membrane traffic, and cell motility, originate at membrane surfaces. Each such event requires that members of a specific group of proteins and lipids rapidly assemble together at a specific site on the membrane surface. Understanding the biophysical mechanisms that stabilize these assemblies is critical to decoding and controlling cellular functions. In this article, we review progress toward a quantitative biophysical understanding of the mechanisms that drive membrane heterogeneity and organization. We begin from a physical perspective, reviewing the fundamental principles and key experimental evidence behind each proposed mechanism. We then shift to a biological perspective, presenting key examples of the role of heterogeneity in biology and asking which physical mechanisms may be responsible. We close with an applied perspective, noting that membrane heterogeneity provides a novel therapeutic target that is being exploited by a growing number of studies at the interface of biology, physics, and engineering.
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Affiliation(s)
- Wade F Zeno
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
| | - Kasey J Day
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
| | - Vernita D Gordon
- Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
- Center for Nonlinear Dynamics, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Jeanne C Stachowiak
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
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29
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Structural Insights into the Regulation Mechanism of Small GTPases by GEFs. Molecules 2019; 24:molecules24183308. [PMID: 31514408 PMCID: PMC6767298 DOI: 10.3390/molecules24183308] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/09/2019] [Accepted: 09/10/2019] [Indexed: 12/12/2022] Open
Abstract
Small GTPases are key regulators of cellular events, and their dysfunction causes many types of cancer. They serve as molecular switches by cycling between inactive guanosine diphosphate (GDP)-bound and active guanosine triphosphate (GTP)-bound states. GTPases are deactivated by GTPase-activating proteins (GAPs) and are activated by guanine-nucleotide exchange factors (GEFs). The intrinsic GTP hydrolysis activity of small GTPases is generally low and is accelerated by GAPs. GEFs promote GDP dissociation from small GTPases to allow for GTP binding, which results in a conformational change of two highly flexible segments, called switch I and switch II, that enables binding of the gamma phosphate and allows small GTPases to interact with downstream effectors. For several decades, crystal structures of many GEFs and GAPs have been reported and have shown tremendous structural diversity. In this review, we focus on the latest structural studies of GEFs. Detailed pictures of the variety of GEF mechanisms at atomic resolution can provide insights into new approaches for drug discovery.
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30
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McLean MA, Stephen AG, Sligar SG. PIP2 Influences the Conformational Dynamics of Membrane-Bound KRAS4b. Biochemistry 2019; 58:3537-3545. [DOI: 10.1021/acs.biochem.9b00395] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Mark A. McLean
- Department of Biochemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Andrew G. Stephen
- NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, Maryland 21701, United States
| | - Stephen G. Sligar
- Department of Biochemistry, University of Illinois, Urbana, Illinois 61801, United States
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31
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Functional link between plasma membrane spatiotemporal dynamics, cancer biology, and dietary membrane-altering agents. Cancer Metastasis Rev 2019; 37:519-544. [PMID: 29860560 DOI: 10.1007/s10555-018-9733-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The cell plasma membrane serves as a nexus integrating extra- and intracellular components, which together enable many of the fundamental cellular signaling processes that sustain life. In order to perform this key function, plasma membrane components assemble into well-defined domains exhibiting distinct biochemical and biophysical properties that modulate various signaling events. Dysregulation of these highly dynamic membrane domains can promote oncogenic signaling. Recently, it has been demonstrated that select membrane-targeted dietary bioactives (MTDBs) have the ability to remodel plasma membrane domains and subsequently reduce cancer risk. In this review, we focus on the importance of plasma membrane domain structural and signaling functionalities as well as how loss of membrane homeostasis can drive aberrant signaling. Additionally, we discuss the intricacies associated with the investigation of these membrane domain features and their associations with cancer biology. Lastly, we describe the current literature focusing on MTDBs, including mechanisms of chemoprevention and therapeutics in order to establish a functional link between these membrane-altering biomolecules, tuning of plasma membrane hierarchal organization, and their implications in cancer prevention.
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Huang WYC, Alvarez S, Kondo Y, Lee YK, Chung JK, Lam HYM, Biswas KH, Kuriyan J, Groves JT. A molecular assembly phase transition and kinetic proofreading modulate Ras activation by SOS. Science 2019; 363:1098-1103. [PMID: 30846600 PMCID: PMC6563836 DOI: 10.1126/science.aau5721] [Citation(s) in RCA: 208] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 01/10/2019] [Indexed: 12/15/2022]
Abstract
The guanine nucleotide exchange factor (GEF) Son of Sevenless (SOS) is a key Ras activator that is autoinhibited in the cytosol and activates upon membrane recruitment. Autoinhibition release involves structural rearrangements of the protein at the membrane and thus introduces a delay between initial recruitment and activation. In this study, we designed a single-molecule assay to resolve the time between initial receptor-mediated membrane recruitment and the initiation of GEF activity of individual SOS molecules on microarrays of Ras-functionalized supported membranes. The rise-and-fall shape of the measured SOS activation time distribution and the long mean time scale to activation (~50 seconds) establish a basis for kinetic proofreading in the receptor-mediated activation of Ras. We further demonstrate that this kinetic proofreading is modulated by the LAT (linker for activation of T cells)-Grb2-SOS phosphotyrosine-driven phase transition at the membrane.
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Affiliation(s)
- William Y C Huang
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
| | - Steven Alvarez
- Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA
| | - Yasushi Kondo
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720, USA
| | - Young Kwang Lee
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
| | - Jean K Chung
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
| | | | - Kabir H Biswas
- Mechanobiology Institute, National University of Singapore, Singapore 117411, Singapore
| | - John Kuriyan
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
- Divisions of Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jay T Groves
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720, USA
- Divisions of Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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Bandaru P, Kondo Y, Kuriyan J. The Interdependent Activation of Son-of-Sevenless and Ras. Cold Spring Harb Perspect Med 2019; 9:cshperspect.a031534. [PMID: 29610148 DOI: 10.1101/cshperspect.a031534] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The guanine-nucleotide exchange factor (GEF) Son-of-Sevenless (SOS) plays a critical role in metazoan signaling by converting Ras•GDP (guanosine diphosphate) to Ras•GTP (guanosine triphosphate) in response to tyrosine kinase activation. Structural studies have shown that SOS differs from other Ras-specific GEFs in that SOS is itself activated by Ras•GTP binding to an allosteric site, distal to the site of nucleotide exchange. The activation of SOS involves membrane recruitment and conformational changes, triggered by lipid binding, that open the allosteric binding site for Ras•GTP. This is in contrast to other Ras-specific GEFs, which are activated by second messengers that more directly affect the active site. Allosteric Ras•GTP binding stabilizes SOS at the membrane, where it can turn over other Ras molecules processively, leading to an ultrasensitive response that is distinct from that of other Ras-specific GEFs.
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Affiliation(s)
- Pradeep Bandaru
- Department of Molecular and Cell Biology, California Institute for Quantitative Biosciences, Howard Hughes Medical Institute, University of California, Berkeley, California 94720
| | - Yasushi Kondo
- Department of Molecular and Cell Biology, California Institute for Quantitative Biosciences, Howard Hughes Medical Institute, University of California, Berkeley, California 94720
| | - John Kuriyan
- Departments of Molecular and Cell Biology and of Chemistry, California Institute for Quantitative Biosciences, Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Howard Hughes Medical Institute, University of California, Berkeley, California 94720
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Zarich N, Anta B, Fernández-Medarde A, Ballester A, de Lucas MP, Cámara AB, Anta B, Oliva JL, Rojas-Cabañeros JM, Santos E. The CSN3 subunit of the COP9 signalosome interacts with the HD region of Sos1 regulating stability of this GEF protein. Oncogenesis 2019; 8:2. [PMID: 30631038 PMCID: PMC6328564 DOI: 10.1038/s41389-018-0111-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 12/03/2018] [Accepted: 12/10/2018] [Indexed: 01/10/2023] Open
Abstract
Sos1 is an universal, widely expressed Ras guanine nucleotide-exchange factor (RasGEF) in eukaryotic cells. Its N-terminal HD motif is known to be involved in allosteric regulation of Sos1 GEF activity through intramolecular interaction with the neighboring PH domain. Here, we searched for other cellular proteins also able to interact productively with the Sos1 HD domain. Using a yeast two-hybrid system, we identified the interaction between the Sos1 HD region and CSN3, the third component of the COP9 signalosome, a conserved, multi-subunit protein complex that functions in the ubiquitin–proteasome pathway to control degradation of many cellular proteins. The interaction of CSN3 with the HD of Sos1 was confirmed in vitro by GST pull-down assays using truncated mutants and reproduced in vivo by co-immunoprecipitation with the endogenous, full-length cellular Sos1 protein. In vitro kinase assays showed that PKD, a COP9 signalosome-associated-kinase, is able to phosphorylate Sos1. The intracellular levels of Sos1 protein were clearly diminished following CSN3 or PKD knockdown. A sizable fraction of the endogenous Sos1 protein was found ubiquitinated in different mammalian cell types. A significant reduction of RasGTP formation upon growth factor stimulation was also observed in CSN3-silenced as compared with control cells. Our data suggest that the interaction of Sos1 with the COP9 signalosome and PKD plays a significant role in maintenance of cellular Sos1 protein stability and homeostasis under physiological conditions and raises the possibility of considering the CSN/PKD complex as a potential target for design of novel therapeutic drugs.
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Affiliation(s)
- Natasha Zarich
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Begoña Anta
- Centro de Investigación del Cáncer, IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007, Salamanca, Spain
| | - Alberto Fernández-Medarde
- Centro de Investigación del Cáncer, IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007, Salamanca, Spain
| | - Alicia Ballester
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - María Pilar de Lucas
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Ana Belén Cámara
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Berta Anta
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - José Luís Oliva
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain.
| | - José M Rojas-Cabañeros
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain.
| | - Eugenio Santos
- Centro de Investigación del Cáncer, IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007, Salamanca, Spain.
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Autoinhibition in Ras effectors Raf, PI3Kα, and RASSF5: a comprehensive review underscoring the challenges in pharmacological intervention. Biophys Rev 2018; 10:1263-1282. [PMID: 30269291 PMCID: PMC6233353 DOI: 10.1007/s12551-018-0461-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 09/17/2018] [Indexed: 02/06/2023] Open
Abstract
Autoinhibition is an effective mechanism that guards proteins against spurious activation. Despite its ubiquity, the distinct organizations of the autoinhibited states and their release mechanisms differ. Signaling is most responsive to the cell environment only if a small shift in the equilibrium is required to switch the system from an inactive (occluded) to an active (exposed) state. Ras signaling follows this paradigm. This underscores the challenge in pharmacological intervention to exploit and enhance autoinhibited states. Here, we review autoinhibition and release mechanisms at the membrane focusing on three representative Ras effectors, Raf protein kinase, PI3Kα lipid kinase, and NORE1A (RASSF5) tumor suppressor, and point to the ramifications to drug discovery. We further touch on Ras upstream and downstream signaling, Ras activation, and the Ras superfamily in this light, altogether providing a broad outlook of the principles and complexities of autoinhibition.
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Liao TJ, Jang H, Fushman D, Nussinov R. Allosteric KRas4B Can Modulate SOS1 Fast and Slow Ras Activation Cycles. Biophys J 2018; 115:629-641. [PMID: 30097175 PMCID: PMC6103739 DOI: 10.1016/j.bpj.2018.07.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 07/18/2018] [Accepted: 07/19/2018] [Indexed: 01/08/2023] Open
Abstract
Membrane-anchored Ras family proteins are activated by guanine nucleotide exchange factors such as SOS1. The CDC25 domain of SOS1 catalyzes GDP-to-GTP exchange, thereby activating Ras. Here, we aim to decipher the activation mechanism of KRas4B, a significantly mutated oncogene. We perform large-scale molecular dynamics simulations on 12 SOS1 systems, scrutinizing each step in two possible KRas4B activation cycles, fast and slow. To activate KRas4B at the CDC25 catalytic site, the allosteric site in the Ras exchanger motif (REM) domain of SOS1 needs to recruit a (nucleotide-bound) KRas4B molecule. Our simulations indicate that KRas4B-GTP interacts with the REM allosteric site more strongly than with the CDC25 catalytic site, consistent with its allosteric role in the GDP-to-GTP exchange. In the fast cycle, the allosteric KRas4B-GTP induces conformational change at the catalytic site. The conformational change facilitates loading KRas4B-GDP at the catalytic site and opening the KRas4B nucleotide-binding site for GDP release and GTP binding. GTP binding reduces the affinity of KRas4B-GTP to the CDC25 catalytic site, resulting in its release. By contrast, in the slow cycle, KRas4B-GDP binds at the allosteric REM site. The limited, altered conformational change that it induces prevents the exact alignments of switch I and II of KRas4B. The increasing binding strength at both binding sites due to interactions of regions other than switch I and II retards GDP release from the catalytic KRas4B, thus KRas4B activation. The accelerated activation cycle supports a positive feedback loop with allosteric signals communicating between the two Ras molecules and is the predominant, native function of SOS. SOS1 activation details may help drug discovery to inhibit Ras activation.
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Affiliation(s)
- Tsung-Jen Liao
- Cancer and Inflammation Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, National Cancer Institute at Frederick, Frederick, Maryland; Biophysics Program
| | - Hyunbum Jang
- Cancer and Inflammation Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, National Cancer Institute at Frederick, Frederick, Maryland
| | - David Fushman
- Biophysics Program; Department of Chemistry and Biochemistry, Center for Biomolecular Structure and Organization, University of Maryland, College Park, Maryland
| | - Ruth Nussinov
- Cancer and Inflammation Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, National Cancer Institute at Frederick, Frederick, Maryland; Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
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37
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Malaby AW, Das S, Chakravarthy S, Irving TC, Bilsel O, Lambright DG. Structural Dynamics Control Allosteric Activation of Cytohesin Family Arf GTPase Exchange Factors. Structure 2017; 26:106-117.e6. [PMID: 29276036 PMCID: PMC5752578 DOI: 10.1016/j.str.2017.11.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 10/22/2017] [Accepted: 11/27/2017] [Indexed: 11/16/2022]
Abstract
Membrane dynamic processes including vesicle biogenesis depend on Arf
GTPase activation by guanine nucleotide exchange factors (GEFs) containing a
catalytic Sec7 domain and a membrane targeting module such as a PH domain. The
catalytic output of cytohesin family Arf GEFs is controlled by autoinhibitory
interactions that impede accessibility of the exchange site in the Sec7 domain.
These restraints can be relieved through activator Arf-GTP binding to an
allosteric site comprising the PH domain and proximal autoinhibitory elements
(Sec7-PH linker and C-terminal helix). Small angle X-ray scattering and
negative-stain electron microscopy were used to investigate the structural
organization and conformational dynamics of Cytohesin-3 (Grp1) in autoinhibited
and active states. The results support a model in which hinge dynamics in the
autoinhibited state expose the activator site for Arf-GTP binding, while
subsequent C-terminal helix unlatching and repositioning unleash conformational
entropy in the Sec7-PH linker to drive exposure of the exchange site.
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Affiliation(s)
- Andrew W Malaby
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA; Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Sanchaita Das
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Srinivas Chakravarthy
- The Biophysics Collaborative Access Team (BioCAT), Department of Biological Sciences, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Thomas C Irving
- The Biophysics Collaborative Access Team (BioCAT), Department of Biological Sciences, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Osman Bilsel
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - David G Lambright
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA; Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01655, USA.
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Czikora A, Kedei N, Kalish H, Blumberg PM. Importance of the REM (Ras exchange) domain for membrane interactions by RasGRP3. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2017; 1859:2350-2360. [PMID: 28912101 PMCID: PMC5659902 DOI: 10.1016/j.bbamem.2017.09.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 09/07/2017] [Accepted: 09/08/2017] [Indexed: 11/18/2022]
Abstract
RasGRP comprises a family of guanine nucleotide exchange factors, regulating the dissociation of GDP from Ras GTPases to enhance the formation of the active GTP-bound form. RasGRP1 possesses REM (Ras exchange), GEF (catalytic), EF-hand, C1, SuPT (suppressor of PT), and PT (plasma membrane-targeting) domains, among which the C1 domain drives membrane localization in response to diacylglycerol or phorbol ester and the PT domain recognizes phosphoinositides. The homologous family member RasGRP3 shows less plasma membrane localization. The objective of this study was to explore the role of the different domains of RasGRP3 in membrane translocation in response to phorbol esters. The full-length RasGRP3 shows limited translocation to the plasma membrane in response to PMA, even when the basic hydrophobic cluster in the PT domain, reported to be critical for RasGRP1 translocation to endogenous activators, is mutated to resemble that of RasGRP1. Moreover, exchange of the C-termini (SuPT-PT domain) of the two proteins had little effect on their plasma membrane translocation. On the other hand, while the C1 domain of RasGRP3 alone showed partial plasma membrane translocation, truncated RasGRP3 constructs, which contain the PT domain and are missing the REM, showed stronger translocation, indicating that the REM of RasGRP3 was a suppressor of its membrane interaction. The REM of RasGRP1 failed to show comparable suppression of RasGRP3 translocation. The marked differences between RasGRP3 and RasGRP1 in membrane interaction necessarily will contribute to their different behavior in cells and are relevant to the design of selective ligands as potential therapeutic agents.
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Affiliation(s)
- Agnes Czikora
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, United States
| | - Noemi Kedei
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, United States
| | - Heather Kalish
- Trans-NIH Shared Resource on Biomedical Engineering and Physical Science (BEPS), National Institute of Biomedical Imaging and Bioengineering (NIBIB) National Institutes of Health, United States
| | - Peter M Blumberg
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, United States.
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Nakamura Y, Umeki N, Abe M, Sako Y. Mutation-Specific Mechanisms of Hyperactivation of Noonan Syndrome SOS Molecules Detected with Single-molecule Imaging in Living Cells. Sci Rep 2017; 7:14153. [PMID: 29074966 PMCID: PMC5658395 DOI: 10.1038/s41598-017-14190-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 10/04/2017] [Indexed: 11/30/2022] Open
Abstract
Noonan syndrome (NS) is a congenital hereditary disorder associated with developmental and cardiac defects. Some patients with NS carry mutations in SOS, a guanine nucleotide exchange factor (GEF) for the small GTPase RAS. NS mutations have been identified not only in the GEF domain, but also in various domains of SOS, suggesting that multiple mechanisms disrupt SOS function. In this study, we examined three NS mutations in different domains of SOS to clarify the abnormality in its translocation to the plasma membrane, where SOS activates RAS. The association and dissociation kinetics between SOS tagged with a fluorescent protein and the living cell surface were observed in single molecules. All three mutants showed increased affinity for the plasma membrane, inducing excessive RAS signalling. However, the mechanisms by which their affinity was increased were specific to each mutant. Conformational disorder in the resting state, increased probability of a conformational change on the plasma membrane, and an increased association rate constant with the membrane receptor are the suggested mechanisms. These different properties cause the specific phenotypes of the mutants, which should be rescuable with different therapeutic strategies. Therefore, single-molecule kinetic analyses of living cells are useful for the pathological analysis of genetic diseases.
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Affiliation(s)
- Yuki Nakamura
- Cellular Informatics Laboratory, RIKEN, 2-1 Hirosawa, Wako, 351-0198, Japan
| | - Nobuhisa Umeki
- Cellular Informatics Laboratory, RIKEN, 2-1 Hirosawa, Wako, 351-0198, Japan
| | - Mitsuhiro Abe
- Cellular Informatics Laboratory, RIKEN, 2-1 Hirosawa, Wako, 351-0198, Japan
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN, 2-1 Hirosawa, Wako, 351-0198, Japan.
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Gerwert K, Mann D, Kötting C. Common mechanisms of catalysis in small and heterotrimeric GTPases and their respective GAPs. Biol Chem 2017; 398:523-533. [PMID: 28245182 DOI: 10.1515/hsz-2016-0314] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 02/15/2017] [Indexed: 01/15/2023]
Abstract
GTPases are central switches in cells. Their dysfunctions are involved in severe diseases. The small GTPase Ras regulates cell growth, differentiation and apoptosis by transmitting external signals to the nucleus. In one group of oncogenic mutations, the 'switch-off' reaction is inhibited, leading to persistent activation of the signaling pathway. The switch reaction is regulated by GTPase-activating proteins (GAPs), which catalyze GTP hydrolysis in Ras, and by guanine nucleotide exchange factors, which catalyze the exchange of GDP for GTP. Heterotrimeric G-proteins are activated by G-protein coupled receptors and are inactivated by GTP hydrolysis in the Gα subunit. Their GAPs are called regulators of G-protein signaling. In the same way that Ras serves as a prototype for small GTPases, Gαi1 is the most well-studied Gα subunit. By utilizing X-ray structural models, time-resolved infrared-difference spectroscopy, and biomolecular simulations, we elucidated the detailed molecular reaction mechanism of the GTP hydrolysis in Ras and Gαi1. In both proteins, the charge distribution of GTP is driven towards the transition state, and an arginine is precisely positioned to facilitate nucleophilic attack of water. In addition to these mechanistic details of GTP hydrolysis, Ras dimerization as an emerging factor in signal transduction is discussed in this review.
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Affiliation(s)
- Klaus Gerwert
- Department of Biophysics, Ruhr-University Bochum, Universitätsstrasse 150, D-44801 Bochum
| | - Daniel Mann
- Department of Biophysics, Ruhr-University Bochum, Universitätsstrasse 150, D-44801 Bochum
| | - Carsten Kötting
- Department of Biophysics, Ruhr-University Bochum, Universitätsstrasse 150, D-44801 Bochum
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Mechanism of SOS PR-domain autoinhibition revealed by single-molecule assays on native protein from lysate. Nat Commun 2017; 8:15061. [PMID: 28452363 PMCID: PMC5414354 DOI: 10.1038/ncomms15061] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Accepted: 02/23/2017] [Indexed: 12/16/2022] Open
Abstract
The guanine nucleotide exchange factor (GEF) Son of Sevenless (SOS) plays a critical role in signal transduction by activating Ras. Here we introduce a single-molecule assay in which individual SOS molecules are captured from raw cell lysate using Ras-functionalized supported membrane microarrays. This enables characterization of the full-length SOS protein, which has not previously been studied in reconstitution due to difficulties in purification. Our measurements on the full-length protein reveal a distinct role of the C-terminal proline-rich (PR) domain to obstruct the engagement of allosteric Ras independently of the well-known N-terminal domain autoinhibition. This inhibitory role of the PR domain limits Grb2-independent recruitment of SOS to the membrane through binding of Ras·GTP in the SOS allosteric binding site. More generally, this assay strategy enables characterization of the functional behaviour of GEFs with single-molecule precision but without the need for purification.
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42
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Christensen SM, Tu HL, Jun JE, Alvarez S, Triplet MG, Iwig JS, Yadav KK, Bar-Sagi D, Roose JP, Groves JT. One-way membrane trafficking of SOS in receptor-triggered Ras activation. Nat Struct Mol Biol 2016; 23:838-46. [PMID: 27501536 PMCID: PMC5016256 DOI: 10.1038/nsmb.3275] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 07/08/2016] [Indexed: 02/07/2023]
Abstract
SOS is a key activator of the small GTPase Ras. In cells, SOS-Ras signaling is thought to be initiated predominantly by membrane recruitment of SOS via the adaptor Grb2 and balanced by rapidly reversible Grb2-SOS binding kinetics. However, SOS has multiple protein and lipid interactions that provide linkage to the membrane. In reconstituted-membrane experiments, these Grb2-independent interactions were sufficient to retain human SOS on the membrane for many minutes, during which a single SOS molecule could processively activate thousands of Ras molecules. These observations raised questions concerning how receptors maintain control of SOS in cells and how membrane-recruited SOS is ultimately released. We addressed these questions in quantitative assays of reconstituted SOS-deficient chicken B-cell signaling systems combined with single-molecule measurements in supported membranes. These studies revealed an essentially one-way trafficking process in which membrane-recruited SOS remains trapped on the membrane and continuously activates Ras until being actively removed via endocytosis.
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Affiliation(s)
- Sune M. Christensen
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Hsiung-Lin Tu
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Jesse E. Jun
- Department of Anatomy, University of California, San Francisco, California, USA
| | - Steven Alvarez
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Meredith G. Triplet
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Jeffrey S. Iwig
- Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley, California, USA
| | - Kamlesh K. Yadav
- Department of Biochemistry, New York University School of Medicine, New York, USA
| | - Dafna Bar-Sagi
- Department of Biochemistry, New York University School of Medicine, New York, USA
| | - Jeroen P. Roose
- Department of Anatomy, University of California, San Francisco, California, USA
| | - Jay T. Groves
- Department of Chemistry, University of California, Berkeley, California, USA
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43
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Vo U, Vajpai N, Embrey KJ, Golovanov AP. Dynamic studies of H-Ras•GTPγS interactions with nucleotide exchange factor Sos reveal a transient ternary complex formation in solution. Sci Rep 2016; 6:29706. [PMID: 27412770 PMCID: PMC4944212 DOI: 10.1038/srep29706] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 06/21/2016] [Indexed: 11/26/2022] Open
Abstract
The cycling between GDP- and GTP- bound forms of the Ras protein is partly regulated by the binding of Sos. The structural/dynamic behavior of the complex formed between activated Sos and Ras at the point of the functional cycle where the nucleotide exchange is completed has not been described to date. Here we show that solution NMR spectra of H-Ras∙GTPγS mixed with a functional fragment of Sos (SosCat) at a 2:1 ratio are consistent with the formation of a rather dynamic assembly. H-Ras∙GTPγS binding was in fast exchange on the NMR timescale and retained a significant degree of molecular tumbling independent of SosCat, while SosCat also tumbled largely independently of H-Ras. Estimates of apparent molecular weight from both NMR data and SEC-MALS revealed that, at most, only one H-Ras∙GTPγS molecule appears stably bound to Sos. The weak transient interaction between Sos and the second H-Ras∙GTPγS may provide a necessary mechanism for complex dissociation upon the completion of the native GDP → GTP exchange reaction, but also explains measurable GTP → GTP exchange activity of Sos routinely observed in in vitro assays that use fluorescently-labelled analogs of GTP. Overall, the data presents the first dynamic snapshot of Ras functional cycle as controlled by Sos.
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Affiliation(s)
- Uybach Vo
- Manchester Institute of Biotechnology and Faculty of Life Sciences, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - Navratna Vajpai
- AstraZeneca, Discovery Sciences, Mereside, Alderley Park, Cheshire, SK10 4TF, UK
| | - Kevin J Embrey
- AstraZeneca, Discovery Sciences, Mereside, Alderley Park, Cheshire, SK10 4TF, UK
| | - Alexander P Golovanov
- Manchester Institute of Biotechnology and Faculty of Life Sciences, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
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44
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Phosphotyrosine-mediated LAT assembly on membranes drives kinetic bifurcation in recruitment dynamics of the Ras activator SOS. Proc Natl Acad Sci U S A 2016; 113:8218-23. [PMID: 27370798 DOI: 10.1073/pnas.1602602113] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The assembly of cell surface receptors with downstream signaling molecules is a commonly occurring theme in multiple signaling systems. However, little is known about how these assemblies modulate reaction kinetics and the ultimate propagation of signals. Here, we reconstitute phosphotyrosine-mediated assembly of extended linker for the activation of T cells (LAT):growth factor receptor-bound protein 2 (Grb2):Son of Sevenless (SOS) networks, derived from the T-cell receptor signaling system, on supported membranes. Single-molecule dwell time distributions reveal two, well-differentiated kinetic species for both Grb2 and SOS on the LAT assemblies. The majority fraction of membrane-recruited Grb2 and SOS both exhibit fast kinetics and single exponential dwell time distributions, with average dwell times of hundreds of milliseconds. The minor fraction exhibits much slower kinetics, extending the dwell times to tens of seconds. Considering this result in the context of the multistep process by which the Ras GEF (guanine nucleotide exchange factor) activity of SOS is activated indicates that kinetic stabilization from the LAT assembly may be important. This kinetic proofreading effect would additionally serve as a stochastic noise filter by reducing the relative probability of spontaneous SOS activation in the absence of receptor triggering. The generality of receptor-mediated assembly suggests that such effects may play a role in multiple receptor proximal signaling processes.
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45
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Christensen SM, Triplet MG, Rhodes C, Iwig JS, Tu HL, Stamou D, Groves JT. Monitoring the Waiting Time Sequence of Single Ras GTPase Activation Events Using Liposome Functionalized Zero-Mode Waveguides. NANO LETTERS 2016; 16:2890-5. [PMID: 27013033 PMCID: PMC5515077 DOI: 10.1021/acs.nanolett.6b00969] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Activation of small GTPases of the Ras superfamily by guanine nucleotide exchange factors (GEFs) is a key step in numerous cell signaling processes. Unveiling the detailed molecular mechanisms of GEF-GTPase signaling interactions is of great importance due to their central roles in cell biology, including critical disease states, and their potential as therapeutic targets. Here we present an assay to monitor individual Ras activation events catalyzed by single molecules of the GEF Son of Sevenless (SOS) in the natural membrane environment. The assay employs zero-mode waveguide (ZMW) nanostructures containing a single Ras-functionalized liposome. The ZMWs facilitate highly localized excitation of fluorophores in the vicinity of the liposome membrane, allowing direct observation of individual Ras activation events as single SOS enzymes catalyze exchange of unlabeled nucleotides bound to Ras with fluorescently labeled nucleotides from solution. The system is compatible with continuous recording of long sequences of individual enzymatic turnover events over hour-long time scales. The single turnover waiting time sequence is a molecular footprint that details the temporal characteristics of the system. Data reported here reveal long-lived activity states that correspond to well-defined conformers of SOS at the membrane. Liposome functionalized ZMWs allow for studies of nucleotide exchange reactions at single GTPase resolution, providing a platform to gauge the mechanisms of these processes.
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Affiliation(s)
- Sune M. Christensen
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Meredith G. Triplet
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Christopher Rhodes
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Jeffrey S. Iwig
- Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley, California 94720, United States
| | - Hsiung-Lin Tu
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Dimitrios Stamou
- Department of Chemistry and Nano-Science Center, University of Copenhagen, Copenhagen, Denmark
| | - Jay T. Groves
- Department of Chemistry, University of California, Berkeley, California 94720, United States
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46
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Nakamura Y, Hibino K, Yanagida T, Sako Y. Switching of the positive feedback for RAS activation by a concerted function of SOS membrane association domains. Biophys Physicobiol 2016; 13:1-11. [PMID: 27924253 PMCID: PMC5042160 DOI: 10.2142/biophysico.13.0_1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 12/11/2015] [Indexed: 01/12/2023] Open
Abstract
Son of sevenless (SOS) is a guanine nucleotide exchange factor that regulates cell behavior by activating the small GTPase RAS. Recent in vitro studies have suggested that an interaction between SOS and the GTP-bound active form of RAS generates a positive feedback loop that propagates RAS activation. However, it remains unclear how the multiple domains of SOS contribute to the regulation of the feedback loop in living cells. Here, we observed single molecules of SOS in living cells to analyze the kinetics and dynamics of SOS behavior. The results indicate that the histone fold and Grb2-binding domains of SOS concertedly produce an intermediate state of SOS on the cell surface. The fraction of the intermediated state was reduced in positive feedback mutants, suggesting that the feedback loop functions during the intermediate state. Translocation of RAF, recognizing the active form of RAS, to the cell surface was almost abolished in the positive feedback mutants. Thus, the concerted functions of multiple membrane-associating domains of SOS governed the positive feedback loop, which is crucial for cell fate decision regulated by RAS.
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Affiliation(s)
- Yuki Nakamura
- Cellular Informatics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan; Nanobiology Laboratories, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Kayo Hibino
- Laboratory for Cell Signaling Dynamics, RIKEN QBiC, Suita, Osaka 565-0874, Japan
| | - Toshio Yanagida
- Nanobiology Laboratories, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan; Nanobiology Laboratories, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
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47
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Coyle SM, Lim WA. Mapping the functional versatility and fragility of Ras GTPase signaling circuits through in vitro network reconstitution. eLife 2016; 5. [PMID: 26765565 PMCID: PMC4775219 DOI: 10.7554/elife.12435] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/13/2016] [Indexed: 01/06/2023] Open
Abstract
The Ras-superfamily GTPases are central controllers of cell proliferation and morphology. Ras signaling is mediated by a system of interacting molecules: upstream enzymes (GEF/GAP) regulate Ras's ability to recruit multiple competing downstream effectors. We developed a multiplexed, multi-turnover assay for measuring the dynamic signaling behavior of in vitro reconstituted H-Ras signaling systems. By including both upstream regulators and downstream effectors, we can systematically map how different network configurations shape the dynamic system response. The concentration and identity of both upstream and downstream signaling components strongly impacted the timing, duration, shape, and amplitude of effector outputs. The distorted output of oncogenic alleles of Ras was highly dependent on the balance of positive (GAP) and negative (GEF) regulators in the system. We found that different effectors interpreted the same inputs with distinct output dynamics, enabling a Ras system to encode multiple unique temporal outputs in response to a single input. We also found that different Ras-to-GEF positive feedback mechanisms could reshape output dynamics in distinct ways, such as signal amplification or overshoot minimization. Mapping of the space of output behaviors accessible to Ras provides a design manual for programming Ras circuits, and reveals how these systems are readily adapted to produce an array of dynamic signaling behaviors. Nonetheless, this versatility comes with a trade-off of fragility, as there exist numerous paths to altered signaling behaviors that could cause disease.
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Affiliation(s)
- Scott M Coyle
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States.,Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, United States.,Program in Biological Sciences, University of California, San Francisco, San Francisco, United States.,Center for Systems and Synthetic Biology, University of California, San Francisco, San Francisco, United States
| | - Wendell A Lim
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States.,Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, United States.,Program in Biological Sciences, University of California, San Francisco, San Francisco, United States.,Center for Systems and Synthetic Biology, University of California, San Francisco, San Francisco, United States
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48
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Vo U, Vajpai N, Flavell L, Bobby R, Breeze AL, Embrey KJ, Golovanov AP. Monitoring Ras Interactions with the Nucleotide Exchange Factor Son of Sevenless (Sos) Using Site-specific NMR Reporter Signals and Intrinsic Fluorescence. J Biol Chem 2015; 291:1703-1718. [PMID: 26565026 PMCID: PMC4722452 DOI: 10.1074/jbc.m115.691238] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Indexed: 01/07/2023] Open
Abstract
The activity of Ras is controlled by the interconversion between GTP- and GDP-bound forms partly regulated by the binding of the guanine nucleotide exchange factor Son of Sevenless (Sos). The details of Sos binding, leading to nucleotide exchange and subsequent dissociation of the complex, are not completely understood. Here, we used uniformly 15N-labeled Ras as well as [13C]methyl-Met,Ile-labeled Sos for observing site-specific details of Ras-Sos interactions in solution. Binding of various forms of Ras (loaded with GDP and mimics of GTP or nucleotide-free) at the allosteric and catalytic sites of Sos was comprehensively characterized by monitoring signal perturbations in the NMR spectra. The overall affinity of binding between these protein variants as well as their selected functional mutants was also investigated using intrinsic fluorescence. The data support a positive feedback activation of Sos by Ras·GTP with Ras·GTP binding as a substrate for the catalytic site of activated Sos more weakly than Ras·GDP, suggesting that Sos should actively promote unidirectional GDP → GTP exchange on Ras in preference of passive homonucleotide exchange. Ras·GDP weakly binds to the catalytic but not to the allosteric site of Sos. This confirms that Ras·GDP cannot properly activate Sos at the allosteric site. The novel site-specific assay described may be useful for design of drugs aimed at perturbing Ras-Sos interactions.
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Affiliation(s)
- Uybach Vo
- From the Manchester Institute of Biotechnology and Faculty of Life Sciences, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom and
| | - Navratna Vajpai
- Discovery Sciences, AstraZeneca, Mereside, Alderley Park, Cheshire SK10 4TF, United Kingdom
| | - Liz Flavell
- Discovery Sciences, AstraZeneca, Mereside, Alderley Park, Cheshire SK10 4TF, United Kingdom
| | - Romel Bobby
- Discovery Sciences, AstraZeneca, Mereside, Alderley Park, Cheshire SK10 4TF, United Kingdom
| | - Alexander L Breeze
- Discovery Sciences, AstraZeneca, Mereside, Alderley Park, Cheshire SK10 4TF, United Kingdom
| | - Kevin J Embrey
- Discovery Sciences, AstraZeneca, Mereside, Alderley Park, Cheshire SK10 4TF, United Kingdom.
| | - Alexander P Golovanov
- From the Manchester Institute of Biotechnology and Faculty of Life Sciences, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom and.
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49
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Cordeddu V, Yin JC, Gunnarsson C, Virtanen C, Drunat S, Lepri F, De Luca A, Rossi C, Ciolfi A, Pugh TJ, Bruselles A, Priest JR, Pennacchio LA, Lu Z, Danesh A, Quevedo R, Hamid A, Martinelli S, Pantaleoni F, Gnazzo M, Daniele P, Lissewski C, Bocchinfuso G, Stella L, Odent S, Philip N, Faivre L, Vlckova M, Seemanova E, Digilio C, Zenker M, Zampino G, Verloes A, Dallapiccola B, Roberts AE, Cavé H, Gelb BD, Neel BG, Tartaglia M. Activating Mutations Affecting the Dbl Homology Domain of SOS2 Cause Noonan Syndrome. Hum Mutat 2015; 36:1080-7. [PMID: 26173643 DOI: 10.1002/humu.22834] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 06/30/2015] [Indexed: 12/24/2022]
Abstract
The RASopathies constitute a family of autosomal-dominant disorders whose major features include facial dysmorphism, cardiac defects, reduced postnatal growth, variable cognitive deficits, ectodermal and skeletal anomalies, and susceptibility to certain malignancies. Noonan syndrome (NS), the commonest RASopathy, is genetically heterogeneous and caused by functional dysregulation of signal transducers and regulatory proteins with roles in the RAS/extracellular signal-regulated kinase (ERK) signal transduction pathway. Mutations in known disease genes account for approximately 80% of affected individuals. Here, we report that missense mutations altering Son of Sevenless, Drosophila, homolog 2 (SOS2), which encodes a RAS guanine nucleotide exchange factor, occur in a small percentage of subjects with NS. Four missense mutations were identified in five unrelated sporadic cases and families transmitting NS. Disease-causing mutations affected three conserved residues located in the Dbl homology (DH) domain, of which two are directly involved in the intramolecular binding network maintaining SOS2 in its autoinhibited conformation. All mutations were found to promote enhanced signaling from RAS to ERK. Similar to NS-causing SOS1 mutations, the phenotype associated with SOS2 defects is characterized by normal development and growth, as well as marked ectodermal involvement. Unlike SOS1 mutations, however, those in SOS2 are restricted to the DH domain.
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Affiliation(s)
- Viviana Cordeddu
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, 00161, Italy.,Dipartimento di Scienze Psicologiche, della Salute e del Territorio, Università degli Studi "G. d'Annunzio", Chieti-Pescara, 66100, Italy
| | - Jiani C Yin
- Princess Margaret Cancer Centre, University Health Network and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, ON, M5S, Canada
| | - Cecilia Gunnarsson
- Department of Clinical and Experimental Medicine, Division of Clinical Genetics, Faculty of Health Sciences, Linköping University, Linköping, 581 83, Sweden
| | - Carl Virtanen
- Princess Margaret Cancer Centre, University Health Network and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, ON, M5S, Canada
| | - Séverine Drunat
- Département de Génétique, Hôpital Robert Debré, Paris, 75019, France
| | - Francesca Lepri
- Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, 00165, Italy
| | - Alessandro De Luca
- IRCCS-Casa Sollievo della Sofferenza Hospital, Mendel Institute, Rome, 00161, Italy
| | - Cesare Rossi
- UO Genetica Medica, Policlinico S.Orsola-Malpighi, Bologna, 40138, Italy
| | - Andrea Ciolfi
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, 00161, Italy
| | - Trevor J Pugh
- Princess Margaret Cancer Centre, University Health Network and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, ON, M5S, Canada
| | - Alessandro Bruselles
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, 00161, Italy
| | - James R Priest
- Division of Pediatric Cardiology, Stanford University School of Medicine, Stanford University, Stanford, California, 94305.,Child Health Research Institute, Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California, 94305
| | - Len A Pennacchio
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California, 94720.,US Department of Energy Joint Genome Institute, Walnut Creek, California, 94598
| | - Zhibin Lu
- Princess Margaret Cancer Centre, University Health Network and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, ON, M5S, Canada
| | - Arnavaz Danesh
- Princess Margaret Cancer Centre, University Health Network and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, ON, M5S, Canada
| | - Rene Quevedo
- Princess Margaret Cancer Centre, University Health Network and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, ON, M5S, Canada
| | - Alaa Hamid
- Princess Margaret Cancer Centre, University Health Network and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, ON, M5S, Canada
| | - Simone Martinelli
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, 00161, Italy
| | - Francesca Pantaleoni
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, 00161, Italy
| | - Maria Gnazzo
- Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, 00165, Italy
| | - Paola Daniele
- IRCCS-Casa Sollievo della Sofferenza Hospital, Mendel Institute, Rome, 00161, Italy
| | - Christina Lissewski
- Institute of Human Genetics, University Hospital of Magdeburg, Otto-von-Guericke-University, Magdeburg, 39106, Germany
| | - Gianfranco Bocchinfuso
- Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma 'Tor Vergata', Rome, 00133, Italy
| | - Lorenzo Stella
- Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma 'Tor Vergata', Rome, 00133, Italy
| | - Sylvie Odent
- Service de Génétique Clinique, Hôpital SUD, Rennes, 35200, France
| | - Nicole Philip
- Département de Génétique Médicale, Hôpital d'Enfants de la Timone, Marseille 13385, France
| | - Laurence Faivre
- Centre de Génétique, Hôpital d'Enfants, Dijon, 21000, France
| | - Marketa Vlckova
- Department of Biology and Medical Genetics, Charles University 2nd Faculty of Medicine and University Hospital Motol, Prague, 150 06, Czech Republic
| | - Eva Seemanova
- Department of Biology and Medical Genetics, Charles University 2nd Faculty of Medicine and University Hospital Motol, Prague, 150 06, Czech Republic
| | - Cristina Digilio
- Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, 00165, Italy
| | - Martin Zenker
- Institute of Human Genetics, University Hospital of Magdeburg, Otto-von-Guericke-University, Magdeburg, 39106, Germany
| | - Giuseppe Zampino
- Istituto di Pediatria, Università Cattolica del Sacro Cuore, Rome, 00168, Italy
| | - Alain Verloes
- Département de Génétique, Hôpital Robert Debré, Paris, 75019, France
| | - Bruno Dallapiccola
- Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, 00165, Italy
| | - Amy E Roberts
- Department of Cardiology and Division of Genetics, Boston Children's Hospital, Boston, Massachusetts, 02115
| | - Hélène Cavé
- Département de Génétique, Hôpital Robert Debré, Paris, 75019, France.,INSERM UMR_S1131, Institut Universitaire d'Hématologie, Université Paris Diderot, Paris-Sorbonne-Cité, Paris, 75205, France
| | - Bruce D Gelb
- The Mindich Child Health and Development Institute, and the Departments of Pediatrics and Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, 10029
| | - Benjamin G Neel
- Princess Margaret Cancer Centre, University Health Network and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, ON, M5S, Canada.,The Laura and Isaac Perlmutter Cancer Center, New York University School of Medicine, New York, New York, 10016
| | - Marco Tartaglia
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, 00161, Italy.,Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, 00165, Italy
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50
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EFA6 controls Arf1 and Arf6 activation through a negative feedback loop. Proc Natl Acad Sci U S A 2014; 111:12378-83. [PMID: 25114232 DOI: 10.1073/pnas.1409832111] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Guanine nucleotide exchange factors (GEFs) of the exchange factor for Arf6 (EFA6), brefeldin A-resistant Arf guanine nucleotide exchange factor (BRAG), and cytohesin subfamilies activate small GTPases of the Arf family in endocytic events. These ArfGEFs carry a pleckstrin homology (PH) domain in tandem with their catalytic Sec7 domain, which is autoinhibitory and supports a positive feedback loop in cytohesins but not in BRAGs, and has an as-yet unknown role in EFA6 regulation. In this study, we analyzed how EFA6A is regulated by its PH and C terminus (Ct) domains by reconstituting its GDP/GTP exchange activity on membranes. We found that EFA6 has a previously unappreciated high efficiency toward Arf1 on membranes and that, similar to BRAGs, its PH domain is not autoinhibitory and strongly potentiates nucleotide exchange on anionic liposomes. However, in striking contrast to both cytohesins and BRAGs, EFA6 is regulated by a negative feedback loop, which is mediated by an allosteric interaction of Arf6-GTP with the PH-Ct domain of EFA6 and monitors the activation of Arf1 and Arf6 differentially. These observations reveal that EFA6, BRAG, and cytohesins have unanticipated commonalities associated with divergent regulatory regimes. An important implication is that EFA6 and cytohesins may combine in a mixed negative-positive feedback loop. By allowing EFA6 to sustain a pool of dormant Arf6-GTP, such a circuit would fulfill the absolute requirement of cytohesins for activation by Arf-GTP before amplification of their GEF activity by their positive feedback loop.
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