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Fischer S, Bürgi J, Gabay-Maskit S, Maier R, Mastalski T, Yifrach E, Obarska-Kosinska A, Rudowitz M, Erdmann R, Platta HW, Wilmanns M, Schuldiner M, Zalckvar E, Oeljeklaus S, Drepper F, Warscheid B. Phosphorylation of the receptor protein Pex5p modulates import of proteins into peroxisomes. Biol Chem 2023; 404:135-155. [PMID: 36122347 PMCID: PMC9929924 DOI: 10.1515/hsz-2022-0168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 08/23/2022] [Indexed: 11/15/2022]
Abstract
Peroxisomes are organelles with vital functions in metabolism and their dysfunction is associated with human diseases. To fulfill their multiple roles, peroxisomes import nuclear-encoded matrix proteins, most carrying a peroxisomal targeting signal (PTS) 1. The receptor Pex5p recruits PTS1-proteins for import into peroxisomes; whether and how this process is posttranslationally regulated is unknown. Here, we identify 22 phosphorylation sites of Pex5p. Yeast cells expressing phospho-mimicking Pex5p-S507/523D (Pex5p2D) show decreased import of GFP with a PTS1. We show that the binding affinity between a PTS1-protein and Pex5p2D is reduced. An in vivo analysis of the effect of the phospho-mimicking mutant on PTS1-proteins revealed that import of most, but not all, cargos is affected. The physiological effect of the phosphomimetic mutations correlates with the binding affinity of the corresponding extended PTS1-sequences. Thus, we report a novel Pex5p phosphorylation-dependent mechanism for regulating PTS1-protein import into peroxisomes. In a broader view, this suggests that posttranslational modifications can function in fine-tuning the peroxisomal protein composition and, thus, cellular metabolism.
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Affiliation(s)
- Sven Fischer
- Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestrasse 1, D-79104Freiburg, Germany
| | - Jérôme Bürgi
- Hamburg Unit c/o DESY, European Molecular Biology Laboratory (EMBL), Notkestrasse 85, D-22607Hamburg, Germany
- University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246Hamburg, Germany
| | - Shiran Gabay-Maskit
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot7610001, Israel
| | - Renate Maier
- Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestrasse 1, D-79104Freiburg, Germany
| | - Thomas Mastalski
- Biochemistry of Intracellular Transport, Medical Faculty, Ruhr University Bochum, D-44780Bochum, Germany
| | - Eden Yifrach
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot7610001, Israel
| | - Agnieszka Obarska-Kosinska
- Hamburg Unit c/o DESY, European Molecular Biology Laboratory (EMBL), Notkestrasse 85, D-22607Hamburg, Germany
- University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246Hamburg, Germany
| | - Markus Rudowitz
- Systems Biochemistry, Medical Faculty, Ruhr-University Bochum, D-44780Bochum, Germany
| | - Ralf Erdmann
- Systems Biochemistry, Medical Faculty, Ruhr-University Bochum, D-44780Bochum, Germany
| | - Harald W. Platta
- Biochemistry of Intracellular Transport, Medical Faculty, Ruhr University Bochum, D-44780Bochum, Germany
| | - Matthias Wilmanns
- Hamburg Unit c/o DESY, European Molecular Biology Laboratory (EMBL), Notkestrasse 85, D-22607Hamburg, Germany
- University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246Hamburg, Germany
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot7610001, Israel
| | - Einat Zalckvar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot7610001, Israel
| | - Silke Oeljeklaus
- Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestrasse 1, D-79104Freiburg, Germany
- Biochemistry II, Theodor Boveri-Institute, Biocenter, University of Würzburg, Am Hubland, D-97074, Würzburg, Germany
| | - Friedel Drepper
- Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestrasse 1, D-79104Freiburg, Germany
| | - Bettina Warscheid
- Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestrasse 1, D-79104Freiburg, Germany
- Biochemistry II, Theodor Boveri-Institute, Biocenter, University of Würzburg, Am Hubland, D-97074, Würzburg, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, D-79104Freiburg, Germany
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2
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Yifrach E, Holbrook-Smith D, Bürgi J, Othman A, Eisenstein M, van Roermund CW, Visser W, Tirosh A, Rudowitz M, Bibi C, Galor S, Weill U, Fadel A, Peleg Y, Erdmann R, Waterham HR, Wanders RJA, Wilmanns M, Zamboni N, Schuldiner M, Zalckvar E. Systematic multi-level analysis of an organelle proteome reveals new peroxisomal functions. Mol Syst Biol 2022; 18:e11186. [PMID: 36164978 PMCID: PMC9513677 DOI: 10.15252/msb.202211186] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 08/29/2022] [Accepted: 09/05/2022] [Indexed: 11/18/2022] Open
Abstract
Seventy years following the discovery of peroxisomes, their complete proteome, the peroxi‐ome, remains undefined. Uncovering the peroxi‐ome is crucial for understanding peroxisomal activities and cellular metabolism. We used high‐content microscopy to uncover peroxisomal proteins in the model eukaryote – Saccharomyces cerevisiae. This strategy enabled us to expand the known peroxi‐ome by ~40% and paved the way for performing systematic, whole‐organellar proteome assays. By characterizing the sub‐organellar localization and protein targeting dependencies into the organelle, we unveiled non‐canonical targeting routes. Metabolomic analysis of the peroxi‐ome revealed the role of several newly identified resident enzymes. Importantly, we found a regulatory role of peroxisomes during gluconeogenesis, which is fundamental for understanding cellular metabolism. With the current recognition that peroxisomes play a crucial part in organismal physiology, our approach lays the foundation for deep characterization of peroxisome function in health and disease.
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Affiliation(s)
- Eden Yifrach
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel
| | | | - Jérôme Bürgi
- Hamburg Unit c/o DESY, European Molecular Biology Laboratory (EMBL), Hamburg, Germany
| | - Alaa Othman
- Institute of Molecular Systems Biology, ETH Zurich, Zurich, Switzerland
| | - Miriam Eisenstein
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel
| | - Carlo Wt van Roermund
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam Gastroenterology, Endocrinology & Metabolism, Amsterdam University Medical Centers - Location AMC, Amsterdam, The Netherlands
| | - Wouter Visser
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam Gastroenterology, Endocrinology & Metabolism, Amsterdam University Medical Centers - Location AMC, Amsterdam, The Netherlands
| | - Asa Tirosh
- Life Sciences Core Facilities (LSCF), The Weizmann Institute of Science, Rehovot, Israel
| | - Markus Rudowitz
- Department of Systems Biochemistry, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Chen Bibi
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel
| | - Shahar Galor
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel
| | - Uri Weill
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel
| | - Amir Fadel
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel
| | - Yoav Peleg
- Life Sciences Core Facilities (LSCF), The Weizmann Institute of Science, Rehovot, Israel
| | - Ralf Erdmann
- Department of Systems Biochemistry, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Hans R Waterham
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam Gastroenterology, Endocrinology & Metabolism, Amsterdam University Medical Centers - Location AMC, Amsterdam, The Netherlands
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam Gastroenterology, Endocrinology & Metabolism, Amsterdam University Medical Centers - Location AMC, Amsterdam, The Netherlands
| | - Matthias Wilmanns
- Hamburg Unit c/o DESY, European Molecular Biology Laboratory (EMBL), Hamburg, Germany.,University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Nicola Zamboni
- Institute of Molecular Systems Biology, ETH Zurich, Zurich, Switzerland
| | - Maya Schuldiner
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel
| | - Einat Zalckvar
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel
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3
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David Y, Castro IG, Yifrach E, Bibi C, Katawi E, Yahav Har-Shai D, Brodsky S, Barkai N, Ravid T, Eisenstein M, Pietrokovski S, Schuldiner M, Zalckvar E. Pls1 Is a Peroxisomal Matrix Protein with a Role in Regulating Lysine Biosynthesis. Cells 2022; 11:1426. [PMID: 35563734 DOI: 10.3390/cells11091426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/13/2022] [Accepted: 04/16/2022] [Indexed: 12/04/2022] Open
Abstract
Peroxisomes host essential metabolic enzymes and are crucial for human health and survival. Although peroxisomes were first described over 60 years ago, their entire proteome has not yet been identified. As a basis for understanding the variety of peroxisomal functions, we used a high-throughput screen to discover peroxisomal proteins in yeast. To visualize low abundance proteins, we utilized a collection of strains containing a peroxisomal marker in which each protein is expressed from the constitutive and strong TEF2 promoter. Using this approach, we uncovered 18 proteins that were not observed in peroxisomes before and could show their metabolic and targeting factor dependence for peroxisomal localization. We focus on one newly identified and uncharacterized matrix protein, Ynl097c-b, and show that it localizes to peroxisomes upon lysine deprivation and that its localization to peroxisomes depends on the lysine biosynthesis enzyme, Lys1. We demonstrate that Ynl097c-b affects the abundance of Lys1 and the lysine biosynthesis pathway. We have therefore renamed this protein Pls1 for Peroxisomal Lys1 Stabilizing 1. Our work uncovers an additional layer of regulation on the central lysine biosynthesis pathway. More generally it highlights how the discovery of peroxisomal proteins can expand our understanding of cellular metabolism.
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Du J, Zheng L, Gao P, Yang H, Yang WJ, Guo F, Liang R, Feng M, Wang Z, Zhang Z, Bai L, Bu Y, Xing S, Zheng W, Wang X, Quan L, Hu X, Wu H, Chen Z, Chen L, Wei K, Zhang Z, Zhu X, Zhang X, Tu Q, Zhao SM, Lei X, Xiong JW. A small-molecule cocktail promotes mammalian cardiomyocyte proliferation and heart regeneration. Cell Stem Cell 2022; 29:545-558.e13. [PMID: 35395187 DOI: 10.1016/j.stem.2022.03.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 01/28/2022] [Accepted: 03/15/2022] [Indexed: 01/07/2023]
Abstract
Zebrafish and mammalian neonates possess robust cardiac regeneration via the induction of endogenous cardiomyocyte (CM) proliferation, but adult mammalian hearts have very limited regenerative potential. Developing small molecules for inducing adult mammalian heart regeneration has had limited success. We report a chemical cocktail of five small molecules (5SM) that promote adult CM proliferation and heart regeneration. A high-content chemical screen, along with an algorithm-aided prediction of small-molecule interactions, identified 5SM that efficiently induced CM cell cycle re-entry and cytokinesis. Intraperitoneal delivery of 5SM reversed the loss of heart function, induced CM proliferation, and decreased cardiac fibrosis after rat myocardial infarction. Mechanistically, 5SM potentially targets α1 adrenergic receptor, JAK1, DYRKs, PTEN, and MCT1 and is connected to lactate-LacRS2 signaling, leading to CM metabolic switching toward glycolysis/biosynthesis and CM de-differentiation before entering the cell-cycle. Our work sheds lights on the understanding CM regenerative mechanisms and opens therapeutic avenues for repairing the heart.
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Affiliation(s)
- Jianyong Du
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China; PKU-Nanjing Institute of Translational Medicine, Nanjing 211800, China
| | - Lixia Zheng
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China; PKU-Nanjing Institute of Translational Medicine, Nanjing 211800, China
| | - Peng Gao
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Hang Yang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China and University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wan-Jie Yang
- Obstetrics and Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Fusheng Guo
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Ruqi Liang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Mengying Feng
- Shanghai East Hospital, Shanghai Institute of Stem Cell Research and Clinical Translation, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Zihao Wang
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Zongwang Zhang
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Linlu Bai
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Ye Bu
- PKU-Nanjing Institute of Translational Medicine, Nanjing 211800, China
| | - Shijia Xing
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Wen Zheng
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Xuelian Wang
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Li Quan
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Xinli Hu
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Haosen Wu
- Division of Cardiac Surgery, the Third Hospital of Peking University, Beijing 100083, China
| | - Zhixing Chen
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Liangyi Chen
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Ke Wei
- Shanghai East Hospital, Shanghai Institute of Stem Cell Research and Clinical Translation, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Zhe Zhang
- Division of Cardiac Surgery, the Third Hospital of Peking University, Beijing 100083, China
| | - Xiaojun Zhu
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China; PKU-Nanjing Institute of Translational Medicine, Nanjing 211800, China
| | | | - Qiang Tu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China and University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shi-Min Zhao
- Obstetrics and Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China.
| | - Xiaoguang Lei
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China.
| | - Jing-Wei Xiong
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Academy for Advanced Interdisciplinary Studies, and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China; PKU-Nanjing Institute of Translational Medicine, Nanjing 211800, China.
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Bansard L, Bouvet O, Moutin E, Le Gall G, Giammona A, Pothin E, Bacou M, Hassen-Khodja C, Bordignon B, Bourgaux JF, Prudhomme M, Hollande F, Pannequin J, Pascussi JM, Planque C. Niclosamide induces miR-148a to inhibit PXR and sensitize colon cancer stem cells to chemotherapy. Stem Cell Reports 2022:S2213-6711(22)00094-7. [PMID: 35276090 DOI: 10.1016/j.stemcr.2022.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 02/04/2022] [Accepted: 02/07/2022] [Indexed: 12/16/2022] Open
Abstract
Tumor recurrence is often attributed to cancer stem cells (CSCs). We previously demonstrated that down-regulation of Pregnane X Receptor (PXR) decreases the chemoresistance of CSCs and prevents colorectal cancer recurrence. Currently, no PXR inhibitor is usable in clinic. Here, we identify miR-148a as a targetable element upstream of PXR signaling in CSCs, which when over-expressed decreases PXR expression and impairs tumor relapse after chemotherapy in mouse tumor xenografts. We then develop a fluorescent reporter screen for miR-148a activators and identify the anti-helminthic drug niclosamide as an inducer of miR-148a expression. Consequently, niclosamide decreased PXR expression and CSC numbers in colorectal cancer patient-derived cell lines and synergized with chemotherapeutic agents to prevent CSC chemoresistance and tumor recurrence in vivo. Our study suggests that endogenous miRNA inducers is a viable strategy to down-regulate PXR and illuminates niclosamide as a neoadjuvant repurposing strategy to prevent tumor relapse in colon cancer. miR-148a expression is decreased in colon cancer stem cells Forced expression of miR-148a inhibits colon cancer stem cell chemoresistance High-content screening identified niclosamide as a potent miR-148a inducer Niclosamide induces miR-148a expression, inhibits PXR expression in CSCs and prevents tumor
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Rubio T, Gagné S, Debruyne C, Dias C, Cluzel C, Mongellaz D, Rousselle P, Göttig S, Seifert H, Higgins PG, Salcedo SP. Incidence of an Intracellular Multiplication Niche among Acinetobacter baumannii Clinical Isolates. mSystems 2022;:e0048821. [PMID: 35103489 DOI: 10.1128/msystems.00488-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The spread of antibiotic-resistant Acinetobacter baumannii poses a significant threat to public health worldwide. This nosocomial bacterial pathogen can be associated with life-threatening infections, particularly in intensive care units. A. baumannii is mainly described as an extracellular pathogen with restricted survival within cells. This study shows that a subset of A. baumannii clinical isolates extensively multiply within nonphagocytic immortalized and primary cells without the induction of apoptosis and with bacterial clusters visible up to 48 h after infection. This phenotype was observed for the A. baumannii C4 strain associated with high mortality in a hospital outbreak and the A. baumannii ABC141 strain, which was isolated from the skin but was found to be hyperinvasive. Intracellular multiplication of these A. baumannii strains occurred within spacious single membrane-bound vacuoles, labeled with the lysosomal associate membrane protein (LAMP1). However, these compartments excluded lysotracker, an indicator of acidic pH, suggesting that A. baumannii can divert its trafficking away from the lysosomal degradative pathway. These compartments were also devoid of autophagy features. A high-content microscopy screen of 43 additional A. baumannii clinical isolates highlighted various phenotypes, and (i) the majority of isolates remained extracellular, (ii) a significant proportion was capable of invasion and limited persistence, and (iii) three more isolates efficiently multiplied within LAMP1-positive vacuoles, one of which was also hyperinvasive. These data identify an intracellular niche for specific A. baumannii clinical isolates that enables extensive multiplication in an environment protected from host immune responses and out of reach of many antibiotics. IMPORTANCE Multidrug-resistant Acinetobacter baumannii isolates are associated with significant morbidity and mortality in hospitals worldwide. Understanding their pathogenicity is critical for improving therapeutic management. Although A. baumannii can steadily adhere to surfaces and host cells, most bacteria remain extracellular. Recent studies have shown that a small proportion of bacteria can invade cells but present limited survival. We have found that some A. baumannii clinical isolates can establish a specialized intracellular niche that sustains extensive intracellular multiplication for a prolonged time without induction of cell death. We propose that this intracellular compartment allows A. baumannii to escape the cell’s normal degradative pathway, protecting bacteria from host immune responses and potentially hindering antibiotic accessibility. This may contribute to A. baumannii persistence, relapsing infections, and enhanced mortality in susceptible patients. A high-content microscopy-based screen confirmed that this pathogenicity trait is present in other clinical A. baumannii isolates. There is an urgent need for new antibiotics or alternative antimicrobial approaches, particularly to combat carbapenem-resistant A. baumannii. The discovery of an intracellular niche for this pathogen, as well as hyperinvasive isolates, may help guide the development of antimicrobial therapies and diagnostics in the future.
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Grafton F, Ho J, Ranjbarvaziri S, Farshidfar F, Budan A, Steltzer S, Maddah M, Loewke KE, Green K, Patel S, Hoey T, Mandegar MA. Deep learning detects cardiotoxicity in a high-content screen with induced pluripotent stem cell-derived cardiomyocytes. eLife 2021; 10:68714. [PMID: 34338636 PMCID: PMC8367386 DOI: 10.7554/elife.68714] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 07/27/2021] [Indexed: 12/15/2022] Open
Abstract
Drug-induced cardiotoxicity and hepatotoxicity are major causes of drug attrition. To decrease late-stage drug attrition, pharmaceutical and biotechnology industries need to establish biologically relevant models that use phenotypic screening to detect drug-induced toxicity in vitro. In this study, we sought to rapidly detect patterns of cardiotoxicity using high-content image analysis with deep learning and induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). We screened a library of 1280 bioactive compounds and identified those with potential cardiotoxic liabilities in iPSC-CMs using a single-parameter score based on deep learning. Compounds demonstrating cardiotoxicity in iPSC-CMs included DNA intercalators, ion channel blockers, epidermal growth factor receptor, cyclin-dependent kinase, and multi-kinase inhibitors. We also screened a diverse library of molecules with unknown targets and identified chemical frameworks that show cardiotoxic signal in iPSC-CMs. By using this screening approach during target discovery and lead optimization, we can de-risk early-stage drug discovery. We show that the broad applicability of combining deep learning with iPSC technology is an effective way to interrogate cellular phenotypes and identify drugs that may protect against diseased phenotypes and deleterious mutations.
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Affiliation(s)
| | - Jaclyn Ho
- Tenaya Therapeutics, South San Francisco, United States
| | - Sara Ranjbarvaziri
- Cardiovascular Institute and Department of Medicine, Stanford University, Stanford, United States
| | | | | | | | | | | | | | - Snahel Patel
- Tenaya Therapeutics, South San Francisco, United States
| | - Tim Hoey
- Tenaya Therapeutics, South San Francisco, United States
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8
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Schummer A, Maier R, Gabay-Maskit S, Hansen T, Mühlhäuser WWD, Suppanz I, Fadel A, Schuldiner M, Girzalsky W, Oeljeklaus S, Zalckvar E, Erdmann R, Warscheid B. Pex14p Phosphorylation Modulates Import of Citrate Synthase 2 Into Peroxisomes in Saccharomyces cerevisiae. Front Cell Dev Biol 2020; 8:549451. [PMID: 33042991 PMCID: PMC7522779 DOI: 10.3389/fcell.2020.549451] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 08/25/2020] [Indexed: 12/16/2022] Open
Abstract
The peroxisomal biogenesis factor Pex14p is an essential component of the peroxisomal matrix protein import machinery. Together with Pex13p and Pex17p, it is part of the membrane-associated peroxisomal docking complex in yeast, facilitating the binding of cargo-loaded receptor proteins for translocation of cargo proteins into the peroxisome. Furthermore, Pex14p is part of peroxisomal import pores. The central role of Pex14p in peroxisomal matrix protein import processes renders it an obvious target for regulatory mechanisms such as protein phosphorylation. To explore this possibility, we examined the state of Pex14p phosphorylation in Saccharomyces cerevisiae. Phos-tag-SDS-PAGE of Pex14p affinity-purified from solubilized membranes revealed Pex14p as multi-phosphorylated protein. Using mass spectrometry, we identified 16 phosphorylation sites, with phosphorylation hot spots located in the N- and C-terminal regions of Pex14p. Analysis of phosphomimicking and non-phosphorylatable variants of Pex14p revealed a decreased import of GFP carrying a peroxisomal targeting signal type 1, indicating a functional relevance of Pex14p phosphorylation in peroxisomal matrix protein import. We show that this effect can be ascribed to the phosphomimicking mutation at serine 266 of Pex14p (Pex14p-S266D). We further screened the subcellular distribution of 23 native GFP-tagged peroxisomal matrix proteins by high-content fluorescence microscopy. Only Cit2p, the peroxisomal isoform of citrate synthase, was affected in the Pex14p-S266D mutant, showing increased cytosolic localization. Cit2p is part of the glyoxylate cycle, which is required for the production of essential carbohydrates when yeast is grown on non-fermentable carbon sources. Pex14p-S266 phosphosite mutants showed reversed growth phenotypes in oleic acid and ethanol with acetyl-CoA formed in peroxisomes and the cytosol, respectively. Overexpression of Cit2p rescued the growth phenotype of yeast cells expressing Pex14p-S266D in oleic acid. Our data indicate that phosphorylation of Pex14p at S266 provides a mechanism for controlling the peroxisomal import of Cit2p, which helps S. cerevisiae cells to adjust their carbohydrate metabolism according to the nutritional conditions.
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Affiliation(s)
- Andreas Schummer
- Faculty of Biology, Biochemistry and Functional Proteomics, Institute of Biology II, University of Freiburg, Freiburg, Germany
| | - Renate Maier
- Faculty of Biology, Biochemistry and Functional Proteomics, Institute of Biology II, University of Freiburg, Freiburg, Germany
| | - Shiran Gabay-Maskit
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Tobias Hansen
- Faculty of Medicine, System Biochemistry, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Wignand W D Mühlhäuser
- Faculty of Biology, Biochemistry and Functional Proteomics, Institute of Biology II, University of Freiburg, Freiburg, Germany
| | - Ida Suppanz
- Faculty of Biology, Biochemistry and Functional Proteomics, Institute of Biology II, University of Freiburg, Freiburg, Germany
| | - Amir Fadel
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Wolfgang Girzalsky
- Faculty of Medicine, System Biochemistry, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Silke Oeljeklaus
- Faculty of Biology, Biochemistry and Functional Proteomics, Institute of Biology II, University of Freiburg, Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Einat Zalckvar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Ralf Erdmann
- Faculty of Medicine, System Biochemistry, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Bettina Warscheid
- Faculty of Biology, Biochemistry and Functional Proteomics, Institute of Biology II, University of Freiburg, Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
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9
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Abstract
Instant and adequate handling of misfolded or otherwise aberrant proteins is of paramount importance for maintaining protein homeostasis in cells. The ubiquitin/proteasome system (UPS) is a central player in protein quality control as it operates in a seek-and-destroy mode, thereby facilitating elimination of faulty proteins. While proteasome inhibition is in clinical use for the treatment of hematopoietic malignancies, stimulation of the UPS has been proposed as a potential therapeutic strategy for various neurodegenerative disorders. High-throughput screens using genetic approaches or compound libraries are powerful tools to identify therapeutic intervention points and novel drugs. Unlike assays that measure specific activities of components of the UPS, reporter substrates provide us with a more holistic view of the general functional status of the UPS in cells. As such, reporter substrates can reveal new ways to obstruct or stimulate this critical proteolytic pathway. Here, we discuss various reporter substrates for the UPS and their application in the identification of key players and the pursuit for novel therapeutics.
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Affiliation(s)
- Maria E Gierisch
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | | | - Nico P Dantuma
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
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10
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Abstract
Cell-permeable compounds provide a convenient and efficient approach to manipulate biological processes. A number of compounds controlling stem cell self-renewal, survival, differentiation, and reprogramming have been identified through high-throughput/content screens. Using these powerful chemical tools, strategies have been developed to direct human pluripotent stem cell (hPSC) differentiation to functional cells. Recently, hPSC-derived cells and organoids are used to model human diseases, which can be adapted to a high-throughput/content platform for chemical screens. The identified compounds provide novel tools for decoding the signaling pathways regulating disease progression and candidates for facilitating future drug discovery. Moreover, humanized mouse models carrying hPSC-derived cells enable an innovative system to evaluate the long-term in vivo efficacy of drug candidates on human cells. In summary, screening-based chemical approaches not only expedite strategy development of controlling stem cell fates, but also provide powerful tools for dissecting the molecular mechanisms regulating disease progression.
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Affiliation(s)
- Shuibing Chen
- Department of Surgery and Biochemistry, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA.
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11
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Abstract
Constellation pharmacology is a cell-based high-content phenotypic-screening platform that utilizes subtype-selective pharmacological agents to elucidate the cell-specific combinations (constellations) of key signaling proteins that define specific cell types. Heterogeneous populations of native cells, in which the different individual cell types have been identified and characterized, are the foundation for this screening platform. Constellation pharmacology is useful for screening small molecules or for deconvoluting complex mixtures of biologically active natural products. This platform has been used to purify natural products and discover their molecular mechanisms. In the ongoing development of constellation pharmacology, there is a positive feedback loop between the pharmacological characterization of cell types and screening for new drug candidates. As constellation pharmacology is used to discover compounds with novel targeting-selectivity profiles, those new compounds then further help to elucidate the constellations of specific cell types, thereby increasing the content of this high-content platform.
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12
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Roosing S, Hofree M, Kim S, Scott E, Copeland B, Romani M, Silhavy JL, Rosti RO, Schroth J, Mazza T, Miccinilli E, Zaki MS, Swoboda KJ, Milisa-Drautz J, Dobyns WB, Mikati MA, İncecik F, Azam M, Borgatti R, Romaniello R, Boustany RM, Clericuzio CL, D'Arrigo S, Strømme P, Boltshauser E, Stanzial F, Mirabelli-Badenier M, Moroni I, Bertini E, Emma F, Steinlin M, Hildebrandt F, Johnson CA, Freilinger M, Vaux KK, Gabriel SB, Aza-Blanc P, Heynen-Genel S, Ideker T, Dynlacht BD, Lee JE, Valente EM, Kim J, Gleeson JG. Functional genome-wide siRNA screen identifies KIAA0586 as mutated in Joubert syndrome. eLife 2015; 4:e06602. [PMID: 26026149 PMCID: PMC4477441 DOI: 10.7554/elife.06602] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 05/28/2015] [Indexed: 12/14/2022] Open
Abstract
Defective primary ciliogenesis or cilium stability forms the basis of human ciliopathies, including Joubert syndrome (JS), with defective cerebellar vermis development. We performed a high-content genome-wide small interfering RNA (siRNA) screen to identify genes regulating ciliogenesis as candidates for JS. We analyzed results with a supervised-learning approach, using SYSCILIA gold standard, Cildb3.0, a centriole siRNA screen and the GTex project, identifying 591 likely candidates. Intersection of this data with whole exome results from 145 individuals with unexplained JS identified six families with predominantly compound heterozygous mutations in KIAA0586. A c.428del base deletion in 0.1% of the general population was found in trans with a second mutation in an additional set of 9 of 163 unexplained JS patients. KIAA0586 is an orthologue of chick Talpid3, required for ciliogenesis and Sonic hedgehog signaling. Our results uncover a relatively high frequency cause for JS and contribute a list of candidates for future gene discoveries in ciliopathies. DOI:http://dx.doi.org/10.7554/eLife.06602.001 Joubert syndrome is a rare disorder that affects the brain and causes physical, mental, and sometimes visual impairments. In individuals with this condition, two parts of the brain called the cerebellar vermis and the brainstem do not develop properly. This is thought to be due to defects in the development and maintenance of tiny hair-like structures called cilia, which are found on the surface of cells. Currently, mutations in 25 different genes are known to be able to cause Joubert syndrome. However, these mutations only account for around 50% of the cases that have been studied, and the ‘unexplained’ cases suggest that mutations in other genes may also cause the disease. Here, Roosing et al. used a technique called a ‘genome-wide siRNA screen’ to identify other genes regulating the formation of cilia that might also be connected with Joubert syndrome. This approach identified almost 600 candidate genes. The data from the screen were combined with gene sequence data from 145 individuals with unexplained Joubert syndrome. Roosing et al. found that individuals with Joubert syndrome from 15 different families had mutations in a gene called KIAA0586. In chickens and mice, this gene—known as Talpid3—is required for the formation of cilia. Roosing et al.'s findings reveal a new gene that is involved in Joubert syndrome and also provides a list of candidate genes for future studies of other conditions caused by defects in the formation of cilia. The next challenges are to find out what causes the remaining unexplained cases of the disease and to understand what roles the genes identified in this study play in cilia. DOI:http://dx.doi.org/10.7554/eLife.06602.002
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Affiliation(s)
- Susanne Roosing
- Laboratory for Pediatric Brain Disease, New York Genome Center, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
| | - Matan Hofree
- Department of Computer Science and Engineering, University of California, San Diego, San Diego, United States
| | - Sehyun Kim
- Department of Pathology and Cancer Institute, Smilow Research Center, New York University School of Medicine, New York, United States
| | - Eric Scott
- Laboratory for Pediatric Brain Disease, New York Genome Center, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
| | - Brett Copeland
- Laboratory for Pediatric Brain Disease, New York Genome Center, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
| | - Marta Romani
- IRCCS Casa Sollievo della Sofferenza, Mendel Institute, San Giovanni Rotondo, Italy
| | - Jennifer L Silhavy
- Laboratory for Pediatric Brain Disease, New York Genome Center, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
| | - Rasim O Rosti
- Laboratory for Pediatric Brain Disease, New York Genome Center, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
| | - Jana Schroth
- Laboratory for Pediatric Brain Disease, New York Genome Center, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
| | - Tommaso Mazza
- IRCCS Casa Sollievo della Sofferenza, Mendel Institute, San Giovanni Rotondo, Italy
| | - Elide Miccinilli
- IRCCS Casa Sollievo della Sofferenza, Mendel Institute, San Giovanni Rotondo, Italy
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Center, Cairo, Egypt
| | - Kathryn J Swoboda
- Departments of Neurology and Pediatrics, University of Utah School of Medicine, Salt Lake City, United States
| | - Joanne Milisa-Drautz
- Department of Pediatric Genetics, University of New Mexico, Albuquerque, United States
| | - William B Dobyns
- Center for Integrative Brain Research, Seattle Children's Hospital, Seattle, United States
| | - Mohamed A Mikati
- Division of Pediatric Neurology, Department of Pediatrics, Duke Institute for Brain Sciences, Duke University Medical Center, Durham, United States
| | - Faruk İncecik
- Department of Pediatric Neurology, Cukurova University Medical Faculty, Balcali, Turkey
| | - Matloob Azam
- Department of Pediatrics and Child Neurology, Wah Medical College, Wah Cantt, Pakistan
| | - Renato Borgatti
- Neuropsychiatry and Neurorehabilitation Unit, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, Italy
| | - Romina Romaniello
- Neuropsychiatry and Neurorehabilitation Unit, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, Italy
| | - Rose-Mary Boustany
- Departments of Pediatrics, Adolescent Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Carol L Clericuzio
- Division of Genetics/Dysmorphology, Department Pediatrics, University of New Mexico, Albuquerque, United States
| | - Stefano D'Arrigo
- Developmental Neurology Division, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Petter Strømme
- Women and Children's Division, Oslo University Hospital, Oslo, Norway
| | - Eugen Boltshauser
- Department of Pediatric Neurology, University Children's Hospital, Zurich, Switzerland
| | - Franco Stanzial
- Department of Pediatrics, Genetic Counselling Service, Regional Hospital of Bolzano, Bolzano, Italy
| | - Marisol Mirabelli-Badenier
- Child Neuropsychiatry Unit, Department of Neurosciences and Rehabilitation, Istituto G. Gaslini, Genoa, Italy
| | - Isabella Moroni
- Unit of Child Neurology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Enrico Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children's Research Hospital, IRCCS, Rome, Italy
| | - Francesco Emma
- Division of Nephrology and Dialysis, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | | | - Friedhelm Hildebrandt
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Howard Hughes Medical Institute, Harvard Medical School, Boston, United States
| | - Colin A Johnson
- Section of Ophthalmology and Neurosciences, Wellcome Trust Brenner Building, Leeds Institute of Molecular Medicine, University of Leeds, St. James's University Hospital, Leeds, United Kingdom
| | - Michael Freilinger
- Neuropediatric group, Department of Paediatrics and Adolescent Medicine, Medical University Vienna, Vienna, Austria
| | - Keith K Vaux
- Laboratory for Pediatric Brain Disease, New York Genome Center, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
| | - Stacey B Gabriel
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, United States
| | - Pedro Aza-Blanc
- High Content Screening Systems, Sanford-Burnham Institute, La Jolla, United States
| | - Susanne Heynen-Genel
- High Content Screening Systems, Sanford-Burnham Institute, La Jolla, United States
| | - Trey Ideker
- Department of Computer Science and Engineering, University of California, San Diego, San Diego, United States
| | - Brian D Dynlacht
- Department of Pathology and Cancer Institute, Smilow Research Center, New York University School of Medicine, New York, United States
| | - Ji Eun Lee
- Samsung Genome Institute, Department of Health Sciences and Technology, Samsung Advanced Institute of Health Sciences and Technology, Sungkyunkwan University, Seoul, Republic of Korea
| | - Enza Maria Valente
- IRCCS Casa Sollievo della Sofferenza, Mendel Institute, San Giovanni Rotondo, Italy
| | - Joon Kim
- Korea Advanced Institute of Science and Technology, School of Medical Science and Engineering, Daejeon, Republic of Korea
| | - Joseph G Gleeson
- Laboratory for Pediatric Brain Disease, New York Genome Center, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
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13
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Zhou X, Wong STC. Computational Systems Bioinformatics and Bioimaging for Pathway Analysis and Drug Screening. Proc IEEE Inst Electr Electron Eng 2008; 96:1310-1331. [PMID: 20011613 PMCID: PMC2790217 DOI: 10.1109/jproc.2008.925440] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The premise of today's drug development is that the mechanism of a disease is highly dependent upon underlying signaling and cellular pathways. Such pathways are often composed of complexes of physically interacting genes, proteins, or biochemical activities coordinated by metabolic intermediates, ions, and other small solutes and are investigated with molecular biology approaches in genomics, proteomics, and metabonomics. Nevertheless, the recent declines in the pharmaceutical industry's revenues indicate such approaches alone may not be adequate in creating successful new drugs. Our observation is that combining methods of genomics, proteomics, and metabonomics with techniques of bioimaging will systematically provide powerful means to decode or better understand molecular interactions and pathways that lead to disease and potentially generate new insights and indications for drug targets. The former methods provide the profiles of genes, proteins, and metabolites, whereas the latter techniques generate objective, quantitative phenotypes correlating to the molecular profiles and interactions. In this paper, we describe pathway reconstruction and target validation based on the proposed systems biologic approach and show selected application examples for pathway analysis and drug screening.
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