1
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Weidner P, Saar D, Söhn M, Schroeder T, Yu Y, Zöllner FG, Ponelies N, Zhou X, Zwicky A, Rohrbacher FN, Pattabiraman VR, Tanriver M, Bauer A, Ahmed H, Ametamey SM, Riffel P, Seger R, Bode JW, Wade RC, Ebert MPA, Kragelund BB, Burgermeister E. Myotubularin-related-protein-7 inhibits mutant (G12V) K-RAS by direct interaction. Cancer Lett 2024; 588:216783. [PMID: 38462034 DOI: 10.1016/j.canlet.2024.216783] [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: 12/04/2023] [Revised: 02/19/2024] [Accepted: 03/03/2024] [Indexed: 03/12/2024]
Abstract
Inhibition of K-RAS effectors like B-RAF or MEK1/2 is accompanied by treatment resistance in cancer patients via re-activation of PI3K and Wnt signaling. We hypothesized that myotubularin-related-protein-7 (MTMR7), which inhibits PI3K and ERK1/2 signaling downstream of RAS, directly targets RAS and thereby prevents resistance. Using cell and structural biology combined with animal studies, we show that MTMR7 binds and inhibits RAS at cellular membranes. Overexpression of MTMR7 reduced RAS GTPase activities and protein levels, ERK1/2 phosphorylation, c-FOS transcription and cancer cell proliferation in vitro. We located the RAS-inhibitory activity of MTMR7 to its charged coiled coil (CC) region and demonstrate direct interaction with the gastrointestinal cancer-relevant K-RASG12V mutant, favouring its GDP-bound state. In mouse models of gastric and intestinal cancer, a cell-permeable MTMR7-CC mimicry peptide decreased tumour growth, Ki67 proliferation index and ERK1/2 nuclear positivity. Thus, MTMR7 mimicry peptide(s) could provide a novel strategy for targeting mutant K-RAS in cancers.
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Affiliation(s)
- Philip Weidner
- Department of Medicine II, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Daniel Saar
- Structural Biology and NMR Laboratory (SBiNLab) and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Michaela Söhn
- Department of Medicine II, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Torsten Schroeder
- Department of Medicine II, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Yanxiong Yu
- Department of Medicine II, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Frank G Zöllner
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; Mannheim Institute for Intelligent Systems in Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; Cooperative Core Facility Animal Scanner ZI, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Norbert Ponelies
- Orthopaedics & Trauma Surgery, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Xiaobo Zhou
- Department of Medicine I, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - André Zwicky
- Laboratory of Organic Chemistry, Department of Chemistry and Applied Bioscience of ETH, Zurich, Switzerland
| | - Florian N Rohrbacher
- Laboratory of Organic Chemistry, Department of Chemistry and Applied Bioscience of ETH, Zurich, Switzerland
| | - Vijaya R Pattabiraman
- Laboratory of Organic Chemistry, Department of Chemistry and Applied Bioscience of ETH, Zurich, Switzerland
| | - Matthias Tanriver
- Laboratory of Organic Chemistry, Department of Chemistry and Applied Bioscience of ETH, Zurich, Switzerland
| | - Alexander Bauer
- Structural Biology and NMR Laboratory (SBiNLab) and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Hazem Ahmed
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences of ETH, Zurich, Switzerland
| | - Simon M Ametamey
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences of ETH, Zurich, Switzerland
| | - Philipp Riffel
- Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Rony Seger
- Department of Immunology and Regenerative Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Jeffrey W Bode
- Laboratory of Organic Chemistry, Department of Chemistry and Applied Bioscience of ETH, Zurich, Switzerland
| | - Rebecca C Wade
- Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany; Heidelberg University, Zentrum für Molekulare Biologie (ZMBH), DKFZ-ZMBH Alliance, and Interdisciplinary Center for Scientific Computing (IWR), Heidelberg, Germany
| | - Matthias P A Ebert
- Department of Medicine II, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; DKFZ-Hector Institute at the University Medical Center, Mannheim, Germany
| | - Birthe B Kragelund
- Structural Biology and NMR Laboratory (SBiNLab) and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
| | - Elke Burgermeister
- Department of Medicine II, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
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2
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Tang J, Lam GT, Brooks RD, Miles M, Useckaite Z, Johnson IR, Ung BSY, Martini C, Karageorgos L, Hickey SM, Selemidis S, Hopkins AM, Rowland A, Vather R, O'Leary JJ, Brooks DA, Caruso MC, Logan JM. Exploring the role of sporadic BRAF and KRAS mutations during colorectal cancer pathogenesis: A spotlight on the contribution of the endosome-lysosome system. Cancer Lett 2024; 585:216639. [PMID: 38290660 DOI: 10.1016/j.canlet.2024.216639] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/21/2023] [Accepted: 12/30/2023] [Indexed: 02/01/2024]
Abstract
The highly heterogenous nature of colorectal cancer can significantly hinder its early and accurate diagnosis, eventually contributing to high mortality rates. The adenoma-carcinoma sequence and serrated polyp-carcinoma sequence are the two most common sequences in sporadic colorectal cancer. Genetic alterations in adenomatous polyposis coli (APC), v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) and tumour protein 53 (TP53) genes are critical in adenoma-carcinoma sequence, whereas v-Raf murine sarcoma viral oncogene homolog B (BRAF) and MutL Homolog1 (MLH1) are driving oncogenes in the serrated polyp-carcinoma sequence. Sporadic mutations in these genes contribute differently to colorectal cancer pathogenesis by introducing distinct alterations in several signalling pathways that rely on the endosome-lysosome system. Unsurprisingly, the endosome-lysosome system plays a pivotal role in the hallmarks of cancer and contributes to specialised colon function. Thus, the endosome-lysosome system might be distinctively influenced by different mutations and these alterations may contribute to the heterogenous nature of sporadic colorectal cancer. This review highlights potential connections between major sporadic colorectal cancer mutations and the diverse pathogenic mechanisms driven by the endosome-lysosome system in colorectal carcinogenesis.
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Affiliation(s)
- Jingying Tang
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Giang T Lam
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Robert D Brooks
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Mark Miles
- School of Health and Biomedical Sciences, STEM College, RMIT University, Bundoora, Melbourne, Vic, Australia
| | - Zivile Useckaite
- College of Medicine and Public Health, Flinders University, Flinders Drive, Bedford Park, Adelaide, SA, Australia
| | - Ian Rd Johnson
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Ben S-Y Ung
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Carmela Martini
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Litsa Karageorgos
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Shane M Hickey
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Stavros Selemidis
- School of Health and Biomedical Sciences, STEM College, RMIT University, Bundoora, Melbourne, Vic, Australia
| | - Ashley M Hopkins
- College of Medicine and Public Health, Flinders University, Flinders Drive, Bedford Park, Adelaide, SA, Australia
| | - Andrew Rowland
- College of Medicine and Public Health, Flinders University, Flinders Drive, Bedford Park, Adelaide, SA, Australia
| | - Ryash Vather
- Colorectal Unit, Department of Surgery, Royal Adelaide Hospital, Adelaide, South Australia, Australia; Centre for Cancer Biology, University of South Australia, Adelaide, South Australia, Australia
| | - John J O'Leary
- Department of Histopathology, Trinity College Dublin, Dublin, Ireland
| | - Douglas A Brooks
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Maria C Caruso
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia
| | - Jessica M Logan
- Clinical and Health Sciences, University of South Australia, North Terrace, Adelaide, South Australia, Australia.
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3
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Biswas S, Mandal G, Anadon CM, Chaurio RA, Lopez-Bailon LU, Nagy MZ, Mine JA, Hänggi K, Sprenger KB, Innamarato P, Harro CM, Powers JJ, Johnson J, Fang B, Eysha M, Nan X, Li R, Perez BA, Curiel TJ, Yu X, Rodriguez PC, Conejo-Garcia JR. Targeting intracellular oncoproteins with dimeric IgA promotes expulsion from the cytoplasm and immune-mediated control of epithelial cancers. Immunity 2023; 56:2570-2583.e6. [PMID: 37909039 PMCID: PMC10703011 DOI: 10.1016/j.immuni.2023.09.013] [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: 10/19/2022] [Revised: 06/05/2023] [Accepted: 09/27/2023] [Indexed: 11/02/2023]
Abstract
Dimeric IgA (dIgA) can move through cells via the IgA/IgM polymeric immunoglobulin receptor (PIGR), which is expressed mainly on mucosal epithelia. Here, we studied the ability of dIgA to target commonly mutated cytoplasmic oncodrivers. Mutation-specific dIgA, but not IgG, neutralized KRASG12D within ovarian carcinoma cells and expelled this oncodriver from tumor cells. dIgA binding changed endosomal trafficking of KRASG12D from accumulation in recycling endosomes to aggregation in the early/late endosomes through which dIgA transcytoses. dIgA targeting of KRASG12D abrogated tumor cell proliferation in cell culture assays. In vivo, KRASG12D-specific dIgA1 limited the growth of KRASG12D-mutated ovarian and lung carcinomas in a manner dependent on CD8+ T cells. dIgA specific for IDH1R132H reduced colon cancer growth, demonstrating effective targeting of a cytoplasmic oncodriver not associated with surface receptors. dIgA targeting of KRASG12D restricted tumor growth more effectively than small-molecule KRASG12D inhibitors, supporting the potential of this approach for the treatment of human cancers.
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Affiliation(s)
- Subir Biswas
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA; Tumor Immunology and Immunotherapy, Advanced Centre for Treatment, Research and Education in Cancer (ACTREC), Tata Memorial Centre, Kharghar, Navi Mumbai 410210, India
| | - Gunjan Mandal
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA; Division of Cancer Biology, DBT-Institute of Life Sciences, Bhubaneswar 751023, India
| | - Carmen M Anadon
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA; Department of Integrated Immunobiology, Duke School of Medicine, Durham, NC 27710, USA; Duke Cancer Institute, Duke School of Medicine, Durham, NC 27710, USA
| | - Ricardo A Chaurio
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA; Department of Integrated Immunobiology, Duke School of Medicine, Durham, NC 27710, USA; Duke Cancer Institute, Duke School of Medicine, Durham, NC 27710, USA
| | - Luis U Lopez-Bailon
- Department of Integrated Immunobiology, Duke School of Medicine, Durham, NC 27710, USA; Duke Cancer Institute, Duke School of Medicine, Durham, NC 27710, USA
| | - Mate Z Nagy
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Jessica A Mine
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA; Department of Integrated Immunobiology, Duke School of Medicine, Durham, NC 27710, USA; Duke Cancer Institute, Duke School of Medicine, Durham, NC 27710, USA
| | - Kay Hänggi
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Kimberly B Sprenger
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Patrick Innamarato
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Carly M Harro
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - John J Powers
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Joseph Johnson
- Analytic Microscopy Core, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Bin Fang
- Proteomics and Metabolomics Core, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Mostafa Eysha
- Department of Medicine, Duke School of Medicine, Durham, NC 27710, USA
| | - Xiaolin Nan
- Department of Biomedical Engineering, Knight Cancer Institute, and OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, OR 97239, USA
| | - Roger Li
- Department of Genitourinary Oncology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Bradford A Perez
- Department of Radiation Therapy, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Tyler J Curiel
- Departments of Medicine and Microbiology and Immunology, Dartmouth Geisel School of Medicine, Hanover, NH 03755, USA
| | - Xiaoqing Yu
- Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Paulo C Rodriguez
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Jose R Conejo-Garcia
- Department of Immunology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA; Department of Integrated Immunobiology, Duke School of Medicine, Durham, NC 27710, USA; Duke Cancer Institute, Duke School of Medicine, Durham, NC 27710, USA.
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4
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Lu H, Martí J. Influence of Cholesterol on the Orientation of the Farnesylated GTP-Bound KRas-4B Binding with Anionic Model Membranes. MEMBRANES 2020; 10:E364. [PMID: 33266473 PMCID: PMC7700388 DOI: 10.3390/membranes10110364] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/18/2020] [Accepted: 11/18/2020] [Indexed: 01/02/2023]
Abstract
The Ras family of proteins is tethered to the inner leaflet of the cell membranes which plays an essential role in signal transduction pathways that promote cellular proliferation, survival, growth, and differentiation. KRas-4B, the most mutated Ras isoform in different cancers, has been under extensive study for more than two decades. Here we have focused our interest on the influence of cholesterol on the orientations that KRas-4B adopts with respect to the plane of the anionic model membranes. How cholesterol in the bilayer might modulate preferences for specific orientation states is far from clear. Herein, after analyzing data from in total 4000 ns-long molecular dynamics (MD) simulations for four KRas-4B systems, properties such as the area per lipid and thickness of the membrane as well as selected radial distribution functions, penetration of different moieties of KRas-4B, and internal conformational fluctuations of flexible moieties in KRas-4B have been calculated. It has been shown that high cholesterol content in the plasma membrane (PM) favors one orientation state (OS1), exposing the effector-binding loop for signal transduction in the cell from the atomic level. We confirm that high cholesterol in the PM helps KRas-4B mutant stay in its constitutively active state, which suggests that high cholesterol intake can increase mortality and may promote cancer progression for cancer patients. We propose that during the treatment of KRas-4B-related cancers, reducing the cholesterol level in the PM and sustaining cancer progression by controlling the plasma cholesterol intake might be taken into account in anti-cancer therapies.
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Affiliation(s)
| | - Jordi Martí
- Department of Physics, Technical University of Catalonia-Barcelona Tech, 08034 Barcelona, Spain;
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5
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Klimpel A, Stillger K, Wiederstein JL, Krüger M, Neundorf I. Cell-permeable CaaX-peptides affect K-Ras downstream signaling and promote cell death in cancer cells. FEBS J 2020; 288:2911-2929. [PMID: 33112492 DOI: 10.1111/febs.15612] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 08/17/2020] [Accepted: 10/26/2020] [Indexed: 12/18/2022]
Abstract
Cysteine prenylation is a post-translational modification that is used by nature to control crucial biological functions of proteins, such as membrane trafficking, signal transduction, and apoptosis. It mainly occurs in eukaryotic proteins at a C-terminal CaaX box and is mediated by prenyltransferases. Since the discovery of prenylated proteins, various tools have been developed to study the mechanisms of prenyltransferases, as well as to visualize and to identify prenylated proteins. Herein, we introduce cell-permeable peptides bearing a C-terminal CaaX motif based on Ras sequences. We demonstrate that intracellular accumulation of those peptides in different cells is controlled by the presence of their CaaX motif and that they specifically interact with intracellular prenyltransferases. As proof of concept, we further highlight their utilization to alter downstream signaling of Ras proteins, particularly of K-Ras-4B, in pancreatic cancer cells. Application of this strategy holds great promise to better understand and regulate post-translational cysteine prenylation.
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Affiliation(s)
- Annika Klimpel
- Institute for Biochemistry, University of Cologne, Germany
| | | | - Janica L Wiederstein
- Institute for Genetics, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Germany
| | - Marcus Krüger
- Institute for Genetics, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Germany.,Center for Molecular Medicine (CMMC), University of Cologne, Germany
| | - Ines Neundorf
- Institute for Biochemistry, University of Cologne, Germany
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6
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Pleiotropic Roles of Calmodulin in the Regulation of KRas and Rac1 GTPases: Functional Diversity in Health and Disease. Int J Mol Sci 2020; 21:ijms21103680. [PMID: 32456244 PMCID: PMC7279331 DOI: 10.3390/ijms21103680] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/18/2020] [Accepted: 05/21/2020] [Indexed: 12/21/2022] Open
Abstract
Calmodulin is a ubiquitous signalling protein that controls many biological processes due to its capacity to interact and/or regulate a large number of cellular proteins and pathways, mostly in a Ca2+-dependent manner. This complex interactome of calmodulin can have pleiotropic molecular consequences, which over the years has made it often difficult to clearly define the contribution of calmodulin in the signal output of specific pathways and overall biological response. Most relevant for this review, the ability of calmodulin to influence the spatiotemporal signalling of several small GTPases, in particular KRas and Rac1, can modulate fundamental biological outcomes such as proliferation and migration. First, direct interaction of calmodulin with these GTPases can alter their subcellular localization and activation state, induce post-translational modifications as well as their ability to interact with effectors. Second, through interaction with a set of calmodulin binding proteins (CaMBPs), calmodulin can control the capacity of several guanine nucleotide exchange factors (GEFs) to promote the switch of inactive KRas and Rac1 to an active conformation. Moreover, Rac1 is also an effector of KRas and both proteins are interconnected as highlighted by the requirement for Rac1 activation in KRas-driven tumourigenesis. In this review, we attempt to summarize the multiple layers how calmodulin can regulate KRas and Rac1 GTPases in a variety of cellular events, with biological consequences and potential for therapeutic opportunities in disease settings, such as cancer.
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7
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Estimating genome-wide off-target effects for pyrrole-imidazole polyamide binding by a pathway-based expression profiling approach. PLoS One 2019; 14:e0215247. [PMID: 30964912 PMCID: PMC6456183 DOI: 10.1371/journal.pone.0215247] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 03/28/2019] [Indexed: 01/17/2023] Open
Abstract
In the search for new pharmaceutical leads, especially with DNA-binding molecules or genome editing methods, the issue of side and off-target effects have always been thorny in nature. A particular case is the investigation into the off-target effects of N-methylpyrrole-N-methylimidazole polyamides, a naturally inspired class of DNA binders with strong affinity to the minor-groove and sequence specificity, but at < 20 bases, their relatively short motifs also insinuate the possibility of non-unique genomic binding. Binding at non-intended loci potentially lead to the rise of off-target effects, issues that very few approaches are able to address to-date. We here report an analytical method to infer off-target binding, via expression profiling, based on probing the relative impact to various biochemical pathways; we also proposed an accompanying side effect prediction engine for the systematic screening of candidate polyamides. This method marks the first attempt in PI polyamide research to identify elements in biochemical pathways that are sensitive to the treatment of a candidate polyamide as an approach to infer possible off-target effects. Expression changes were then considered to assess possible outward phenotypic changes, manifested as side effects, should the same PI polyamide candidate be administered clinically. We validated some of these effects with a series of animal experiments, and found agreeable corroboration in certain side effects, such as changes in aspartate transaminase levels in ICR and nude mice post-administration.
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8
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Tebar F, Enrich C, Rentero C, Grewal T. GTPases Rac1 and Ras Signaling from Endosomes. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2018; 57:65-105. [PMID: 30097772 DOI: 10.1007/978-3-319-96704-2_3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The endocytic compartment is not only the functional continuity of the plasma membrane but consists of a diverse collection of intracellular heterogeneous complex structures that transport, amplify, sustain, and/or sort signaling molecules. Over the years, it has become evident that early, late, and recycling endosomes represent an interconnected vesicular-tubular network able to form signaling platforms that dynamically and efficiently translate extracellular signals into biological outcome. Cell activation, differentiation, migration, death, and survival are some of the endpoints of endosomal signaling. Hence, to understand the role of the endosomal system in signal transduction in space and time, it is therefore necessary to dissect and identify the plethora of decoders that are operational in the different steps along the endocytic pathway. In this chapter, we focus on the regulation of spatiotemporal signaling in cells, considering endosomes as central platforms, in which several small GTPases proteins of the Ras superfamily, in particular Ras and Rac1, actively participate to control cellular processes like proliferation and cell mobility.
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Affiliation(s)
- Francesc Tebar
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain.
| | - Carlos Enrich
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Carles Rentero
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Thomas Grewal
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, 2006, Australia
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9
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Gulyás G, Radvánszki G, Matuska R, Balla A, Hunyady L, Balla T, Várnai P. Plasma membrane phosphatidylinositol 4-phosphate and 4,5-bisphosphate determine the distribution and function of K-Ras4B but not H-Ras proteins. J Biol Chem 2017; 292:18862-18877. [PMID: 28939768 DOI: 10.1074/jbc.m117.806679] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 09/11/2017] [Indexed: 11/06/2022] Open
Abstract
Plasma membrane (PM) localization of Ras proteins is crucial for transmitting signals upon mitogen stimulation. Post-translational lipid modification of Ras proteins plays an important role in their recruitment to the PM. Electrostatic interactions between negatively charged PM phospholipids and basic amino acids found in K-Ras4B (K-Ras) but not in H-Ras are important for permanent K-Ras localization to the PM. Here, we investigated how acute depletion of negatively charged PM polyphosphoinositides (PPIns) from the PM alters the intracellular distribution and activity of K- and H-Ras proteins. PPIns depletion from the PM was achieved either by agonist-induced activation of phospholipase C β or with a rapamycin-inducible system in which various phosphatidylinositol phosphatases were recruited to the PM. Redistribution of the two Ras proteins was monitored with confocal microscopy or with a recently developed bioluminescence resonance energy transfer-based approach involving fusion of the Ras C-terminal targeting sequences or the entire Ras proteins to Venus fluorescent protein. We found that PM PPIns depletion caused rapid translocation of K-Ras but not H-Ras from the PM to the Golgi. PM depletion of either phosphatidylinositol 4-phosphate (PtdIns4P) or PtdIns(4,5)P2 but not PtdIns(3,4,5)P3 was sufficient to evoke K-Ras translocation. This effect was diminished by deltarasin, an inhibitor of the Ras-phosphodiesterase interaction, or by simultaneous depletion of the Golgi PtdIns4P. The PPIns depletion decreased incorporation of [3H]leucine in K-Ras-expressing cells, suggesting that Golgi-localized K-Ras is not as signaling-competent as its PM-bound form. We conclude that PPIns in the PM are important regulators of K-Ras-mediated signals.
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Affiliation(s)
- Gergő Gulyás
- From the Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest 1094, Hungary
| | - Glória Radvánszki
- From the Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest 1094, Hungary
| | - Rita Matuska
- From the Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest 1094, Hungary
| | - András Balla
- From the Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest 1094, Hungary.,MTA-SE Laboratory of Molecular Physiology, Hungarian Academy of Sciences and Semmelweis University, Budapest 1094, Hungary, and
| | - László Hunyady
- From the Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest 1094, Hungary.,MTA-SE Laboratory of Molecular Physiology, Hungarian Academy of Sciences and Semmelweis University, Budapest 1094, Hungary, and
| | - Tamas Balla
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, Maryland 20892
| | - Péter Várnai
- From the Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest 1094, Hungary,
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10
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Teske C, Schweitzer C, Palamidessi A, Aust DE, Scita G, Weitz J, Welsch T. Modulation of RAB5A early endosome trafficking in response to KRas mediated macropinocytic fluxes in pancreatic cancer cells. Biochem Biophys Res Commun 2017; 493:528-533. [PMID: 28867190 DOI: 10.1016/j.bbrc.2017.08.157] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 08/31/2017] [Indexed: 12/26/2022]
Abstract
KRAS is the key mutated gene in pancreatic ductal adenocarcinoma (PDAC). Emerging evidence indicates that KRas modulates endocytic uptake. The present study aimed to explore the fate of early endosomal trafficking under the control of KRas expression in PDAC. Surprisingly, PANC-1 cells lacking KRas exhibited significantly enlarged early and late endosomes containing internalized dextran and epidermal growth factor. Endosome enlargement was accompanied by reduced endosomal degradation. Both KRas silencing and lysosomal blockade caused an upregulation of the master regulator of early endosome biogenesis, RAB5A, which is likely responsible for the expansion of the early endosomal compartment, because simultaneous KRAS/RAB5A knockdown abolished endosome enlargement. In contrast, early endosome shrinkage was seen in MIA PaCa-2 cells despite RAB5A upregulation, indicating that distinct KRas-modulated responses operate in different metabolic subtypes of PDAC. In conclusion, mutant KRAS promotes endosomal degradation in PDAC cell lines, which is impaired by KRAS silencing. Moreover, KRAS silencing activates RAB5A upregulation and drives PDAC subtype-dependent modulation of endosome trafficking.
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Affiliation(s)
- Christian Teske
- Department of Visceral, Thoracic and Vascular Surgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Christine Schweitzer
- Department of Visceral, Thoracic and Vascular Surgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Andrea Palamidessi
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139, Milan, Italy; Department of Hemato-Oncology (DIPO), University of Milan, Italy
| | - Daniela E Aust
- Institute for Pathology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Giorgio Scita
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139, Milan, Italy; Department of Hemato-Oncology (DIPO), University of Milan, Italy
| | - Jürgen Weitz
- Department of Visceral, Thoracic and Vascular Surgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Thilo Welsch
- Department of Visceral, Thoracic and Vascular Surgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany.
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11
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Luhtala N, Aslanian A, Yates JR, Hunter T. Secreted Glioblastoma Nanovesicles Contain Intracellular Signaling Proteins and Active Ras Incorporated in a Farnesylation-dependent Manner. J Biol Chem 2016; 292:611-628. [PMID: 27909058 DOI: 10.1074/jbc.m116.747618] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 11/11/2016] [Indexed: 12/21/2022] Open
Abstract
Glioblastomas (GBMs) are malignant brain tumors with a median survival of less than 18 months. Redundancy of signaling pathways represented within GBMs contributes to their therapeutic resistance. Exosomes are extracellular nanovesicles released from cells and present in human biofluids that represent a possible biomarker of tumor signaling state that could aid in personalized treatment. Herein, we demonstrate that mouse GBM cell-derived extracellular nanovesicles resembling exosomes from an H-RasV12 myr-Akt mouse model for GBM are enriched for intracellular signaling cascade proteins (GO: 0007242) and Ras protein signal transduction (GO: 0007265), and contain active Ras. Active Ras isolated from human and mouse GBM extracellular nanovesicles lysates using the Ras-binding domain of Raf also coprecipitates with ESCRT (endosomal sorting complex required for transport)-associated exosome proteins Vps4a and Alix. Although we initially hypothesized a role for active Ras protein signaling in exosome biogenesis, we found that GTP binding of K-Ras was dispensable for its packaging within extracellular nanovesicles and for the release of Alix. By contrast, farnesylation of K-Ras was required for its packaging within extracellular nanovesicles, yet expressing a K-Ras farnesylation mutant did not decrease the number of nanovesicles or the amount of Alix protein released per cell. Overall, these results emphasize the primary importance of membrane association in packaging of extracellular nanovesicle factors and indicate that screening nanovesicles within human fluids could provide insight into tissue origin and the wiring of signaling proteins at membranes to predict onset and behavior of cancer and other diseases linked to deregulated membrane signaling states.
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Affiliation(s)
- Natalie Luhtala
- From the Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037 and
| | - Aaron Aslanian
- From the Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037 and.,the Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037
| | - John R Yates
- the Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037
| | - Tony Hunter
- From the Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037 and
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12
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Murphy J, Kolandaivelu S. Palmitoylation of Progressive Rod-Cone Degeneration (PRCD) Regulates Protein Stability and Localization. J Biol Chem 2016; 291:23036-23046. [PMID: 27613864 DOI: 10.1074/jbc.m116.742767] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Indexed: 11/06/2022] Open
Abstract
Progressive rod-cone degeneration (PRCD) is a photoreceptor outer segment (OS) disc-specific protein with unknown function that is associated with retinitis pigmentosa (RP). The most common mutation in PRCD linked with severe RP phenotype is substitution of the only cysteine to tyrosine (C2Y). In this study, we find that PRCD is post-translationally modified by a palmitoyl lipid group at the cysteine residue linked with RP. Disrupting PRCD palmitoylation either chemically or by genetically eliminating the modified cysteine dramatically affects the stability of PRCD. Furthermore, in vivo electroporation of PRCD C2Y mutant in the mouse retina demonstrates that the palmitoylation of PRCD is important for its proper localization in the photoreceptor OS. Mutant PRCD C2Y was found in the inner segment in contrast to normal localization of WT PRCD in the OS. Our results also suggest that zDHHC3, a palmitoyl acyltransferase (PAT), catalyzes the palmitoylation of PRCD in the Golgi compartment. In conclusion, we find that the palmitoylation of PRCD is crucial for its trafficking to the photoreceptor OS and mislocalization of this protein likely leads to RP-related phenotypes.
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Affiliation(s)
- Joseph Murphy
- From the Department of Ophthalmology, West Virginia University Eye institute, Morgantown, West Virginia 26506
| | - Saravanan Kolandaivelu
- From the Department of Ophthalmology, West Virginia University Eye institute, Morgantown, West Virginia 26506
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13
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Meehan TL, Joudi TF, Timmons AK, Taylor JD, Habib CS, Peterson JS, Emmanuel S, Franc NC, McCall K. Components of the Engulfment Machinery Have Distinct Roles in Corpse Processing. PLoS One 2016; 11:e0158217. [PMID: 27347682 PMCID: PMC4922577 DOI: 10.1371/journal.pone.0158217] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 06/13/2016] [Indexed: 01/10/2023] Open
Abstract
Billions of cells die in our bodies on a daily basis and are engulfed by phagocytes. Engulfment, or phagocytosis, can be broken down into five basic steps: attraction of the phagocyte, recognition of the dying cell, internalization, phagosome maturation, and acidification. In this study, we focus on the last two steps, which can collectively be considered corpse processing, in which the engulfed material is degraded. We use the Drosophila ovarian follicle cells as a model for engulfment of apoptotic cells by epithelial cells. We show that engulfed material is processed using the canonical corpse processing pathway involving the small GTPases Rab5 and Rab7. The phagocytic receptor Draper is present on the phagocytic cup and on nascent, phosphatidylinositol 3-phosphate (PI(3)P)- and Rab7-positive phagosomes, whereas integrins are maintained on the cell surface during engulfment. Due to the difference in subcellular localization, we investigated the role of Draper, integrins, and downstream signaling components in corpse processing. We found that some proteins were required for internalization only, while others had defects in corpse processing as well. This suggests that several of the core engulfment proteins are required for distinct steps of engulfment. We also performed double mutant analysis and found that combined loss of draper and αPS3 still resulted in a small number of engulfed vesicles. Therefore, we investigated another known engulfment receptor, Crq. We found that loss of all three receptors did not inhibit engulfment any further, suggesting that Crq does not play a role in engulfment by the follicle cells. A more complete understanding of how the engulfment and corpse processing machinery interact may enable better understanding and treatment of diseases associated with defects in engulfment by epithelial cells.
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Affiliation(s)
- Tracy L. Meehan
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- * E-mail: (KM); (TM)
| | - Tony F. Joudi
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Allison K. Timmons
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Jeffrey D. Taylor
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Corey S. Habib
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Jeanne S. Peterson
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Shanan Emmanuel
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Nathalie C. Franc
- The Scripps Research Institute, Department of Immunology and Microbial Science, La Jolla, California, United States of America
| | - Kimberly McCall
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- * E-mail: (KM); (TM)
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14
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Abstract
RAS proteins (KRAS4A, KRAS4B, NRAS and HRAS) function as GDP-GTP-regulated binary on-off switches, which regulate cytoplasmic signaling networks that control diverse normal cellular processes. Gain-of-function missense mutations in RAS genes are found in ∼25% of human cancers, prompting interest in identifying anti-RAS therapeutic strategies for cancer treatment. However, despite more than three decades of intense effort, no anti-RAS therapies have reached clinical application. Contributing to this failure has been an underestimation of the complexities of RAS. First, there is now appreciation that the four human RAS proteins are not functionally identical. Second, with >130 different missense mutations found in cancer, there is an emerging view that there are mutation-specific consequences on RAS structure, biochemistry and biology, and mutation-selective therapeutic strategies are needed. In this Cell Science at a Glance article and accompanying poster, we provide a snapshot of the differences between RAS isoforms and mutations, as well as the current status of anti-RAS drug-discovery efforts.
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Affiliation(s)
- G Aaron Hobbs
- University of North Carolina at Chapel Hill, Lineberger Comprehensive Cancer Center, Chapel Hill, NC 27514, USA
| | - Channing J Der
- University of North Carolina at Chapel Hill, Lineberger Comprehensive Cancer Center, Chapel Hill, NC 27514, USA
| | - Kent L Rossman
- University of North Carolina at Chapel Hill, Lineberger Comprehensive Cancer Center, Chapel Hill, NC 27514, USA
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15
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Chavan TS, Muratcioglu S, Marszalek R, Jang H, Keskin O, Gursoy A, Nussinov R, Gaponenko V. Plasma membrane regulates Ras signaling networks. CELLULAR LOGISTICS 2015; 5:e1136374. [PMID: 27054048 PMCID: PMC4820813 DOI: 10.1080/21592799.2015.1136374] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 12/17/2015] [Indexed: 12/31/2022]
Abstract
Ras GTPases activate more than 20 signaling pathways, regulating such essential cellular functions as proliferation, survival, and migration. How Ras proteins control their signaling diversity is still a mystery. Several pieces of evidence suggest that the plasma membrane plays a critical role. Among these are: (1) selective recruitment of Ras and its effectors to particular localities allowing access to Ras regulators and effectors; (2) specific membrane-induced conformational changes promoting Ras functional diversity; and (3) oligomerization of membrane-anchored Ras to recruit and activate Raf. Taken together, the membrane does not only attract and retain Ras but also is a key regulator of Ras signaling. This can already be gleaned from the large variability in the sequences of Ras membrane targeting domains, suggesting that localization, environment and orientation are important factors in optimizing the function of Ras isoforms.
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Affiliation(s)
- Tanmay Sanjeev Chavan
- Department of Medicinal Chemistry; University of Illinois at Chicago; Chicago, IL USA
| | - Serena Muratcioglu
- Center for Computational Biology and Bioinformatics; Koc University; Istanbul, Turkey
| | - Richard Marszalek
- Department of Biochemistry and Molecular Genetics; University of Illinois at Chicago; Chicago, IL USA
| | - Hyunbum Jang
- Cancer and Inflammation Program; Basic Science Program; Leidos Biomedical Research, Inc.; Frederick National Laboratory for Cancer Research; National Cancer Institute at Frederick; Frederick, MD USA
| | - Ozlem Keskin
- Center for Computational Biology and Bioinformatics; Koc University; Istanbul, Turkey
| | - Attila Gursoy
- Center for Computational Biology and Bioinformatics; Koc University; Istanbul, Turkey
| | - Ruth Nussinov
- Cancer and Inflammation Program; Basic Science Program; Leidos Biomedical Research, Inc.; Frederick National Laboratory for Cancer Research; National Cancer Institute at Frederick; Frederick, MD USA
- Sackler Institute of Molecular Medicine; Department of Human Genetics and Molecular Medicine; Sackler School of Medicine; Tel Aviv University; Tel Aviv, Israel
| | - Vadim Gaponenko
- Department of Biochemistry and Molecular Genetics; University of Illinois at Chicago; Chicago, IL USA
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16
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Lee S, Uchida Y, Wang J, Matsudaira T, Nakagawa T, Kishimoto T, Mukai K, Inaba T, Kobayashi T, Molday RS, Taguchi T, Arai H. Transport through recycling endosomes requires EHD1 recruitment by a phosphatidylserine translocase. EMBO J 2015; 34:669-88. [PMID: 25595798 PMCID: PMC4365035 DOI: 10.15252/embj.201489703] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
P4-ATPases translocate aminophospholipids, such as phosphatidylserine (PS), to the cytosolic leaflet of membranes. PS is highly enriched in recycling endosomes (REs) and is essential for endosomal membrane traffic. Here, we show that PS flipping by an RE-localized P4-ATPase is required for the recruitment of the membrane fission protein EHD1. Depletion of ATP8A1 impaired the asymmetric transbilayer distribution of PS in REs, dissociated EHD1 from REs, and generated aberrant endosomal tubules that appear resistant to fission. EHD1 did not show membrane localization in cells defective in PS synthesis. ATP8A2, a tissue-specific ATP8A1 paralogue, is associated with a neurodegenerative disease (CAMRQ). ATP8A2, but not the disease-causative ATP8A2 mutant, rescued the endosomal defects in ATP8A1-depleted cells. Primary neurons from Atp8a2-/- mice showed a reduced level of transferrin receptors at the cell surface compared to Atp8a2+/+ mice. These findings demonstrate the role of P4-ATPase in membrane fission and give insight into the molecular basis of CAMRQ.
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Affiliation(s)
- Shoken Lee
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences University of Tokyo, Tokyo, Japan
| | - Yasunori Uchida
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences University of Tokyo, Tokyo, Japan
| | - Jiao Wang
- Departments of Biochemistry and Molecular Biology and Ophthalmology and Visual Sciences, Centre for Macular Research University of British Columbia, Vancouver, BC, Canada
| | - Tatsuyuki Matsudaira
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences University of Tokyo, Tokyo, Japan
| | - Takatoshi Nakagawa
- Department of Pharmacology, Osaka Medical College, Takatsuki-city Osaka, Japan
| | | | - Kojiro Mukai
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences University of Tokyo, Tokyo, Japan Lipid Biology Laboratory, RIKEN, Wako-shi Saitama, Japan
| | - Takehiko Inaba
- Lipid Biology Laboratory, RIKEN, Wako-shi Saitama, Japan
| | | | - Robert S Molday
- Departments of Biochemistry and Molecular Biology and Ophthalmology and Visual Sciences, Centre for Macular Research University of British Columbia, Vancouver, BC, Canada
| | - Tomohiko Taguchi
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences University of Tokyo, Tokyo, Japan Pathological Cell Biology Laboratory, Graduate School of Pharmaceutical Sciences University of Tokyo, Tokyo, Japan
| | - Hiroyuki Arai
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences University of Tokyo, Tokyo, Japan Pathological Cell Biology Laboratory, Graduate School of Pharmaceutical Sciences University of Tokyo, Tokyo, Japan
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