51
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Experimental and engineering approaches to intracellular communication. Essays Biochem 2018; 62:515-524. [PMID: 30139878 DOI: 10.1042/ebc20180024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 08/10/2018] [Accepted: 08/14/2018] [Indexed: 11/17/2022]
Abstract
Communication between and within cells is essential for multicellular life. While intracellular signal transduction pathways are often specified in molecular terms, the information content they transmit remains poorly defined. Here, we review research efforts to merge biological experimentation with concepts of communication that emerge from the engineering disciplines of signal processing and control theory. We discuss the challenges of performing experiments that quantitate information transfer at the molecular level, and we highlight recent studies that have advanced toward a clearer definition of the information content carried by signaling molecules. Across these studies, we emphasize a theme of increasingly well-matched experimental and theoretical approaches to decode the data streams directing cellular behavior.
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52
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Ishizuka S, Lai CY, Otsu M, Nakauchi H, Nagamune T, Kawahara M. Designing Motif-Engineered Receptors To Elucidate Signaling Molecules Important for Proliferation of Hematopoietic Stem Cells. ACS Synth Biol 2018; 7:1709-1714. [PMID: 29920201 DOI: 10.1021/acssynbio.8b00163] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The understanding of signaling events is critical for attaining long-term expansion of hematopoietic stem cells ex vivo. In this study, we aim to analyze the contribution of multiple signaling molecules in proliferation of hematopoietic stem cells. To this end, we design a bottom-up engineered receptor with multiple tyrosine motifs, which can recruit multiple signaling molecules of interest. This is followed by a top-down approach, where one of the multiple tyrosine motifs in the bottom-up engineered receptor is functionally knocked out by tyrosine-to-phenylalanine mutation. The combination of these two approaches demonstrates the importance of Shc in cooperation with STAT3 or STAT5 in the proliferation of hematopoietic stem cells. The platform developed herein may be applied for analyzing other cells and/or other cell fate regulation systems.
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Affiliation(s)
- Shuta Ishizuka
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Chen-Yi Lai
- Division of Stem Cell Processing/Stem Cell Bank, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
| | - Makoto Otsu
- Division of Stem Cell Processing/Stem Cell Bank, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
| | - Hiromitsu Nakauchi
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Teruyuki Nagamune
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Masahiro Kawahara
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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53
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Sampattavanich S, Steiert B, Kramer BA, Gyori BM, Albeck JG, Sorger PK. Encoding Growth Factor Identity in the Temporal Dynamics of FOXO3 under the Combinatorial Control of ERK and AKT Kinases. Cell Syst 2018; 6:664-678.e9. [PMID: 29886111 DOI: 10.1016/j.cels.2018.05.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 12/19/2017] [Accepted: 05/04/2018] [Indexed: 02/05/2023]
Abstract
Extracellular growth factors signal to transcription factors via a limited number of cytoplasmic kinase cascades. It remains unclear how such cascades encode ligand identities and concentrations. In this paper, we use live-cell imaging and statistical modeling to study FOXO3, a transcription factor regulating diverse aspects of cellular physiology that is under combinatorial control. We show that FOXO3 nuclear-to-cytosolic translocation has two temporally distinct phases varying in magnitude with growth factor identity and cell type. These phases comprise synchronous translocation soon after ligand addition followed by an extended back-and-forth shuttling; this shuttling is pulsatile and does not have a characteristic frequency, unlike a simple oscillator. Early and late dynamics are differentially regulated by Akt and ERK and have low mutual information, potentially allowing the two phases to encode different information. In cancer cells in which ERK and Akt are dysregulated by oncogenic mutation, the diversity of states is lower.
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Affiliation(s)
- Somponnat Sampattavanich
- HMS LINCS Center and Laboratory of Systems Pharmacology, Department of Systems Biology, Harvard Medical School, WAB Room 438, 200 Longwood Avenue, Boston, MA 02115, USA; Siriraj Laboratory for Systems Pharmacology, Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Mahidol University, 12th Floor Srisavarindhira Building, 2 Wanglang Road, Bangkoknoi, Bangkok 10700, Thailand.
| | - Bernhard Steiert
- HMS LINCS Center and Laboratory of Systems Pharmacology, Department of Systems Biology, Harvard Medical School, WAB Room 438, 200 Longwood Avenue, Boston, MA 02115, USA; Institute of Physics, University of Freiburg, Freiburg, Germany; Freiburg Center for Systems Biology, University of Freiburg, Freiburg, Germany
| | - Bernhard A Kramer
- HMS LINCS Center and Laboratory of Systems Pharmacology, Department of Systems Biology, Harvard Medical School, WAB Room 438, 200 Longwood Avenue, Boston, MA 02115, USA; Division of Systems Biology of Signal Transduction, German Cancer Research Center, Heidelberg, Germany
| | - Benjamin M Gyori
- HMS LINCS Center and Laboratory of Systems Pharmacology, Department of Systems Biology, Harvard Medical School, WAB Room 438, 200 Longwood Avenue, Boston, MA 02115, USA
| | - John G Albeck
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
| | - Peter K Sorger
- HMS LINCS Center and Laboratory of Systems Pharmacology, Department of Systems Biology, Harvard Medical School, WAB Room 438, 200 Longwood Avenue, Boston, MA 02115, USA.
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54
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Muta Y, Fujita Y, Sumiyama K, Sakurai A, Taketo MM, Chiba T, Seno H, Aoki K, Matsuda M, Imajo M. Composite regulation of ERK activity dynamics underlying tumour-specific traits in the intestine. Nat Commun 2018; 9:2174. [PMID: 29872037 PMCID: PMC5988836 DOI: 10.1038/s41467-018-04527-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 05/02/2018] [Indexed: 02/07/2023] Open
Abstract
Acting downstream of many growth factors, extracellular signal-regulated kinase (ERK) plays a pivotal role in regulating cell proliferation and tumorigenesis, where its spatiotemporal dynamics, as well as its strength, determine cellular responses. Here, we uncover the ERK activity dynamics in intestinal epithelial cells (IECs) and their association with tumour characteristics. Intravital imaging identifies two distinct modes of ERK activity, sustained and pulse-like activity, in IECs. The sustained and pulse-like activities depend on ErbB2 and EGFR, respectively. Notably, activation of Wnt signalling, the earliest event in intestinal tumorigenesis, augments EGFR signalling and increases the frequency of ERK activity pulses through controlling the expression of EGFR and its regulators, rendering IECs sensitive to EGFR inhibition. Furthermore, the increased pulse frequency is correlated with increased cell proliferation. Thus, ERK activity dynamics are defined by composite inputs from EGFR and ErbB2 signalling in IECs and their alterations might underlie tumour-specific sensitivity to pharmacological EGFR inhibition. The ERK signalling pathway regulates homeostasis of the intestinal epithelium. Here the authors identify two modes of ERK activity generated independently from EGFR and ErbB2 receptor and whose balance in cancer is shifted by Wnt pathway activation, resulting in enhanced sensitivity to EGFR inhibitors.
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Affiliation(s)
- Yu Muta
- Department of Pathology and Biology of Diseases, Graduate School of Medicine, Kyoto University, Kyoto, 606-8051, Japan.,Department of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Yoshihisa Fujita
- Department of Systems Science, Graduate School of Informatics, Kyoto University, Kyoto, 606-8501, Japan
| | - Kenta Sumiyama
- Laboratory for Mouse Genetic Engineering, Quantitative Biology Center, RIKEN, Osaka, 565-0874, Japan
| | - Atsuro Sakurai
- Laboratory of Bioimaging and Cell Signaling, Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan
| | - M Mark Taketo
- Division of Experimental Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan
| | - Tsutomu Chiba
- Department of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan.,Kansai Electric Power Hospital, Osaka, 553-0003, Japan
| | - Hiroshi Seno
- Department of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Kazuhiro Aoki
- Division of Quantitative Biology, Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, 444-8787, Japan.,Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), Myodaiji, Okazaki, Aichi, 444-8787, Japan
| | - Michiyuki Matsuda
- Department of Pathology and Biology of Diseases, Graduate School of Medicine, Kyoto University, Kyoto, 606-8051, Japan.,Laboratory of Bioimaging and Cell Signaling, Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan
| | - Masamichi Imajo
- Laboratory of Bioimaging and Cell Signaling, Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan.
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55
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Hamann JC, Surcel A, Chen R, Teragawa C, Albeck JG, Robinson DN, Overholtzer M. Entosis Is Induced by Glucose Starvation. Cell Rep 2018; 20:201-210. [PMID: 28683313 PMCID: PMC5559205 DOI: 10.1016/j.celrep.2017.06.037] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 05/05/2017] [Accepted: 06/13/2017] [Indexed: 12/20/2022] Open
Abstract
Entosis is a mechanism of cell death that involves neighbor cell ingestion. This process occurs in cancers and promotes a form of cell competition, where winner cells engulf and kill losers. Entosis is driven by a mechanical differential that allows softer cells to eliminate stiffer cells. While this process can be induced by matrix detachment, whether other stressors can activate entosis is unknown. Here, we find that entosis is induced in adherent cells by glucose withdrawal. Glucose withdrawal leads to a bimodal distribution of cells based on their deformability, where stiffer cells appear in a manner requiring the energy-sensing AMP-activated protein kinase (AMPK). We show that loser cells with high levels of AMPK activity are eliminated by winners through entosis, which supports winner cell proliferation under nutrient-deprived conditions. Our findings demonstrate that entosis serves as a cellular response to metabolic stress that enables nutrient recovery through neighbor cell ingestion.
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Affiliation(s)
- Jens C Hamann
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Louis V. Gerstner, Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Alexandra Surcel
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ruoyao Chen
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; BCMB Allied Program, Weill Cornell Medical College, New York, NY 10065, USA
| | - Carolyn Teragawa
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA
| | - John G Albeck
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA
| | - Douglas N Robinson
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Michael Overholtzer
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
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56
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Abstract
The ERK1 and ERK2 (ERK1/2) cascade is a central signaling pathway activated by a wide variety of extracellular agents that transmit the messages of G Protein Coupled Receptors (GPCRs) and Receptor Tyrosine Kinases (RTKs). Being such a central pathway, the activity of the cascade is well regulated, including by dynamic changes of the subcellular localization of components of the ERK1/2 cascade. In resting cells, ERK1/2 are localized in the cytosol due to their interactions with different anchoring proteins. After stimulation, ERK1/2 are phosphorylated by MEK1/2 on their regulatory TEY motif, which permits their detachment from the anchoring proteins. This detachment exposes ERK1/2 to additional phosphorylation on two serine residues (SPS motif) within the nuclear translocation signal (NTS) of the kinases. This additional phosphorylation allows ERK1/2 to interact with importin7, which consequently promotes their translocation to the nucleus. More studies are still required in order to better understand the mechanism and consequence of the nuclear translocation of ERK1/2. In this chapter, we describe some of the techniques used to study nuclear translocation of ERK1/2 in mammalian cells. We briefly mention methods such as digitonin permeabilization and cellular fractionation, as well as overexpression of reporter constructs. More thoroughly, we describe immunofluorescence, immunoprecipitation, and proximity ligation assay (PLA) approaches that are routinely used in our laboratory. Hopefully, the increase of knowledge based on these methods will open more opportunities for the identification of new therapeutic targets for diseases where the ERK1/2 cascade is dysregulated, such as cancer, neurodegenerative diseases, and diabetes.
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Affiliation(s)
- Denise A Berti
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Rony Seger
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, 76100, Israel.
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57
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Hung YP, Teragawa C, Kosaisawe N, Gillies TE, Pargett M, Minguet M, Distor K, Rocha-Gregg BL, Coloff JL, Keibler MA, Stephanopoulos G, Yellen G, Brugge JS, Albeck JG. Akt regulation of glycolysis mediates bioenergetic stability in epithelial cells. eLife 2017; 6:27293. [PMID: 29239720 PMCID: PMC5730373 DOI: 10.7554/elife.27293] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 12/05/2017] [Indexed: 12/26/2022] Open
Abstract
Cells use multiple feedback controls to regulate metabolism in response to nutrient and signaling inputs. However, feedback creates the potential for unstable network responses. We examined how concentrations of key metabolites and signaling pathways interact to maintain homeostasis in proliferating human cells, using fluorescent reporters for AMPK activity, Akt activity, and cytosolic NADH/NAD+ redox. Across various conditions, including glycolytic or mitochondrial inhibition or cell proliferation, we observed distinct patterns of AMPK activity, including both stable adaptation and highly dynamic behaviors such as periodic oscillations and irregular fluctuations that indicate a failure to reach a steady state. Fluctuations in AMPK activity, Akt activity, and cytosolic NADH/NAD+ redox state were temporally linked in individual cells adapting to metabolic perturbations. By monitoring single-cell dynamics in each of these contexts, we identified PI3K/Akt regulation of glycolysis as a multifaceted modulator of single-cell metabolic dynamics that is required to maintain metabolic stability in proliferating cells.
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Affiliation(s)
- Yin P Hung
- Department of Cell Biology, Harvard Medical School, Boston, United States.,Department of Neurobiology, Harvard Medical School, Boston, United States.,Department of Pathology, Brigham and Women's Hospital, Boston, United States
| | - Carolyn Teragawa
- Department of Molecular and Cellular Biology, University of California, Davis, United States
| | - Nont Kosaisawe
- Department of Molecular and Cellular Biology, University of California, Davis, United States
| | - Taryn E Gillies
- Department of Molecular and Cellular Biology, University of California, Davis, United States
| | - Michael Pargett
- Department of Molecular and Cellular Biology, University of California, Davis, United States
| | - Marta Minguet
- Department of Molecular and Cellular Biology, University of California, Davis, United States
| | - Kevin Distor
- Department of Molecular and Cellular Biology, University of California, Davis, United States
| | - Briana L Rocha-Gregg
- Department of Molecular and Cellular Biology, University of California, Davis, United States
| | - Jonathan L Coloff
- Department of Cell Biology, Harvard Medical School, Boston, United States
| | - Mark A Keibler
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, United States
| | - Gregory Stephanopoulos
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, United States
| | - Gary Yellen
- Department of Neurobiology, Harvard Medical School, Boston, United States
| | - Joan S Brugge
- Department of Cell Biology, Harvard Medical School, Boston, United States
| | - John G Albeck
- Department of Molecular and Cellular Biology, University of California, Davis, United States
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58
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Gillies TE, Pargett M, Minguet M, Davies AE, Albeck JG. Linear Integration of ERK Activity Predominates over Persistence Detection in Fra-1 Regulation. Cell Syst 2017; 5:549-563.e5. [PMID: 29199017 DOI: 10.1016/j.cels.2017.10.019] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 08/29/2017] [Accepted: 10/27/2017] [Indexed: 12/14/2022]
Abstract
ERK signaling regulates the expression of target genes, but it is unclear how ERK activity dynamics are interpreted. Here, we investigate this question using simultaneous, live, single-cell imaging of two ERK activity reporters and expression of Fra-1, a target gene controlling epithelial cell identity. We find that Fra-1 is expressed in proportion to the amplitude and duration of ERK activity. In contrast to previous "persistence detector" and "selective filter" models in which Fra-1 expression only occurs when ERK activity persists beyond a threshold duration, our observations demonstrate that the network regulating Fra-1 expression integrates total ERK activity and responds to it linearly. However, exploration of a generalized mathematical model of the Fra-1 coherent feedforward loop demonstrates that it can perform either linear integration or persistence detection, depending on the basal mRNA production rate and protein production delays. Our data indicate that significant basal expression and short delays cause Fra-1 to respond linearly to integrated ERK activity.
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Affiliation(s)
- Taryn E Gillies
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
| | - Michael Pargett
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
| | - Marta Minguet
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
| | - Alex E Davies
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA; Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - John G Albeck
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA.
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59
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Freed DM, Bessman NJ, Kiyatkin A, Salazar-Cavazos E, Byrne PO, Moore JO, Valley CC, Ferguson KM, Leahy DJ, Lidke DS, Lemmon MA. EGFR Ligands Differentially Stabilize Receptor Dimers to Specify Signaling Kinetics. Cell 2017; 171:683-695.e18. [PMID: 28988771 DOI: 10.1016/j.cell.2017.09.017] [Citation(s) in RCA: 229] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 07/31/2017] [Accepted: 09/12/2017] [Indexed: 12/21/2022]
Abstract
Epidermal growth factor receptor (EGFR) regulates many crucial cellular programs, with seven different activating ligands shaping cell signaling in distinct ways. Using crystallography and other approaches, we show how the EGFR ligands epiregulin (EREG) and epigen (EPGN) stabilize different dimeric conformations of the EGFR extracellular region. As a consequence, EREG or EPGN induce less stable EGFR dimers than EGF-making them partial agonists of EGFR dimerization. Unexpectedly, this weakened dimerization elicits more sustained EGFR signaling than seen with EGF, provoking responses in breast cancer cells associated with differentiation rather than proliferation. Our results reveal how responses to different EGFR ligands are defined by receptor dimerization strength and signaling dynamics. These findings have broad implications for understanding receptor tyrosine kinase (RTK) signaling specificity. Our results also suggest parallels between partial and/or biased agonism in RTKs and G-protein-coupled receptors, as well as new therapeutic opportunities for correcting RTK signaling output.
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Affiliation(s)
- Daniel M Freed
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Nicholas J Bessman
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6059, USA
| | - Anatoly Kiyatkin
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Emanuel Salazar-Cavazos
- Department of Pathology and UNM Comprehensive Cancer Center, University of New Mexico Health Science Center, Albuquerque, NM 87131, USA
| | - Patrick O Byrne
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Jason O Moore
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6059, USA
| | - Christopher C Valley
- Department of Pathology and UNM Comprehensive Cancer Center, University of New Mexico Health Science Center, Albuquerque, NM 87131, USA
| | - Kathryn M Ferguson
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Daniel J Leahy
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Diane S Lidke
- Department of Pathology and UNM Comprehensive Cancer Center, University of New Mexico Health Science Center, Albuquerque, NM 87131, USA
| | - Mark A Lemmon
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, Yale University, West Haven, CT 06516, USA; Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6059, USA.
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60
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de la Cova C, Townley R, Regot S, Greenwald I. A Real-Time Biosensor for ERK Activity Reveals Signaling Dynamics during C. elegans Cell Fate Specification. Dev Cell 2017; 42:542-553.e4. [PMID: 28826819 PMCID: PMC5595649 DOI: 10.1016/j.devcel.2017.07.014] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 06/19/2017] [Accepted: 07/20/2017] [Indexed: 01/06/2023]
Abstract
Kinase translocation reporters (KTRs) are genetically encoded fluorescent activity sensors that convert kinase activity into a nucleocytoplasmic shuttling equilibrium for visualizing single-cell signaling dynamics. Here, we adapt the first-generation KTR for extracellular signal-regulated kinase (ERK) to allow easy implementation in vivo. This sensor, "ERK-nKTR," allows quantitative and qualitative assessment of ERK activity by analysis of individual nuclei and faithfully reports ERK activity during development and neural function in diverse cell contexts in Caenorhabditis elegans. Analysis of ERK activity over time in the vulval precursor cells, a well-characterized paradigm of epidermal growth factor receptor (EGFR)-Ras-ERK signaling, has identified dynamic features not evident from analysis of developmental endpoints alone, including pulsatile frequency-modulated signaling associated with proximity to the EGF source. The toolkit described here will facilitate studies of ERK signaling in other C. elegans contexts, and the design features will enable implementation of this technology in other multicellular organisms.
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Affiliation(s)
- Claire de la Cova
- Department of Biological Sciences, Columbia University, New York, NY, USA; Department of Biochemistry & Molecular Biophysics, Columbia University Medical Center, New York, NY, USA
| | - Robert Townley
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Sergi Regot
- Department of Molecular Biology & Genetics, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Iva Greenwald
- Department of Biological Sciences, Columbia University, New York, NY, USA; Department of Biochemistry & Molecular Biophysics, Columbia University Medical Center, New York, NY, USA.
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61
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Gross SM, Rotwein P. Quantification of growth factor signaling and pathway cross talk by live-cell imaging. Am J Physiol Cell Physiol 2017; 312:C328-C340. [PMID: 28100485 DOI: 10.1152/ajpcell.00312.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 01/05/2017] [Accepted: 01/10/2017] [Indexed: 01/20/2023]
Abstract
Peptide growth factors stimulate cellular responses through activation of their transmembrane receptors. Multiple intracellular signaling cascades are engaged following growth factor-receptor binding, leading to short- and long-term biological effects. Each receptor-activated signaling pathway does not act in isolation but rather interacts at different levels with other pathways to shape signaling networks that are distinctive for each growth factor. To gain insights into the specifics of growth factor-regulated interactions among different signaling cascades, we developed a HeLa cell line stably expressing fluorescent live-cell imaging reporters that are readouts for two major growth factor-stimulated pathways, Ras-Raf-Mek-ERK and phosphatidylinositol (PI) 3-kinase-Akt. Incubation of cells with epidermal growth factor (EGF) resulted in rapid, robust, and sustained ERK signaling but shorter-term activation of Akt. In contrast, hepatocyte growth factor induced sustained Akt signaling but weak and short-lived ERK activity, and insulin-like growth factor-I stimulated strong long-term Akt responses but negligible ERK signaling. To address potential interactions between signaling pathways, we employed specific small-molecule inhibitors. In cells incubated with EGF or platelet-derived growth factor-AA, Raf activation and the subsequent stimulation of ERK reduced Akt signaling, whereas Mek inhibition, which blocked ERK activation, enhanced Akt and turned transient effects into sustained responses. Our results reveal that individual growth factors initiate signaling cascades that vary markedly in strength and duration and demonstrate in living cells the dramatic effects of cross talk from Raf and Mek to PI 3-kinase and Akt. Our data further indicate how specific growth factors can encode distinct cellular behaviors by promoting complex interactions among signaling pathways.
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Affiliation(s)
- Sean M Gross
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon; and
| | - Peter Rotwein
- Department of Biomedical Sciences, Paul L. Foster School of Medicine, Texas Tech Health University Health Sciences Center, El Paso, Texas
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62
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Relaxation oscillations and hierarchy of feedbacks in MAPK signaling. Sci Rep 2017; 7:38244. [PMID: 28045041 PMCID: PMC5206726 DOI: 10.1038/srep38244] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/07/2016] [Indexed: 12/21/2022] Open
Abstract
We formulated a computational model for a MAPK signaling cascade downstream of the EGF receptor to investigate how interlinked positive and negative feedback loops process EGF signals into ERK pulses of constant amplitude but dose-dependent duration and frequency. A positive feedback loop involving RAS and SOS, which leads to bistability and allows for switch-like responses to inputs, is nested within a negative feedback loop that encompasses RAS and RAF, MEK, and ERK that inhibits SOS via phosphorylation. This negative feedback, operating on a longer time scale, changes switch-like behavior into oscillations having a period of 1 hour or longer. Two auxiliary negative feedback loops, from ERK to MEK and RAF, placed downstream of the positive feedback, shape the temporal ERK activity profile but are dispensable for oscillations. Thus, the positive feedback introduces a hierarchy among negative feedback loops, such that the effect of a negative feedback depends on its position with respect to the positive feedback loop. Furthermore, a combination of the fast positive feedback involving slow-diffusing membrane components with slower negative feedbacks involving faster diffusing cytoplasmic components leads to local excitation/global inhibition dynamics, which allows the MAPK cascade to transmit paracrine EGF signals into spatially non-uniform ERK activity pulses.
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63
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Abstract
Single-cell analysis of the mitogen-activated protein kinase (MAPK) extracellular signal-regulated kinase (ERK) provides a means to perform highly detailed kinetic studies, assess heterogeneity between cells, and distinguish the subcellular localization of ERK activity. We describe here the methods needed to perform such measurements in a cell type of the investigator's choosing. We discuss the selection of appropriate reporters and provide detailed methods for stably introducing reporters, collecting live-cell data, and automatically extracting quantitative information from individual cells.
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64
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Handly LN, Yao J, Wollman R. Signal Transduction at the Single-Cell Level: Approaches to Study the Dynamic Nature of Signaling Networks. J Mol Biol 2016; 428:3669-82. [PMID: 27430597 PMCID: PMC5023475 DOI: 10.1016/j.jmb.2016.07.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/07/2016] [Accepted: 07/11/2016] [Indexed: 12/16/2022]
Abstract
Signal transduction, or how cells interpret and react to external events, is a fundamental aspect of cellular function. Traditional study of signal transduction pathways involves mapping cellular signaling pathways at the population level. However, population-averaged readouts do not adequately illuminate the complex dynamics and heterogeneous responses found at the single-cell level. Recent technological advances that observe cellular response, computationally model signaling pathways, and experimentally manipulate cells now enable studying signal transduction at the single-cell level. These studies will enable deeper insights into the dynamic nature of signaling networks.
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Affiliation(s)
- L Naomi Handly
- Departments of Chemistry and Biochemistry, Integrative Biology and Physiology, and Institute for Quantitative and Computational Biosciences (QCB), UCLA, Los Angeles, CA 90095, USA
| | - Jason Yao
- Departments of Chemistry and Biochemistry, Integrative Biology and Physiology, and Institute for Quantitative and Computational Biosciences (QCB), UCLA, Los Angeles, CA 90095, USA
| | - Roy Wollman
- Departments of Chemistry and Biochemistry, Integrative Biology and Physiology, and Institute for Quantitative and Computational Biosciences (QCB), UCLA, Los Angeles, CA 90095, USA.
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65
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Rauch N, Rukhlenko OS, Kolch W, Kholodenko BN. MAPK kinase signalling dynamics regulate cell fate decisions and drug resistance. Curr Opin Struct Biol 2016; 41:151-158. [PMID: 27521656 DOI: 10.1016/j.sbi.2016.07.019] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 07/29/2016] [Indexed: 01/21/2023]
Abstract
The RAS/RAF/MEK/MAPK kinase pathway has been extensively studied for more than 25 years, yet we continue to be puzzled by its intricate dynamic control and plasticity. Different spatiotemporal MAPK dynamics bring about distinct cell fate decisions in normal vs cancer cells and developing organisms. Recent modelling and experimental studies provided novel insights in the versatile MAPK dynamics concerted by a plethora of feedforward/feedback regulations and crosstalk on multiple timescales. Multiple cancer types and various developmental disorders arise from persistent alterations of the MAPK dynamics caused by RAS/RAF/MEK mutations. While a key role of the MAPK pathway in multiple diseases made the development of novel RAF/MEK inhibitors a hot topic of drug development, these drugs have unexpected side-effects and resistance inevitably occurs. We review how RAF dimerization conveys drug resistance and recent breakthroughs to overcome this resistance.
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Affiliation(s)
- Nora Rauch
- Systems Biology Ireland, University College Dublin, Ireland
| | | | - Walter Kolch
- Systems Biology Ireland, University College Dublin, Ireland; Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Ireland; School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Boris N Kholodenko
- Systems Biology Ireland, University College Dublin, Ireland; Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Ireland; School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland.
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66
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Lemmon MA, Freed DM, Schlessinger J, Kiyatkin A. The Dark Side of Cell Signaling: Positive Roles for Negative Regulators. Cell 2016; 164:1172-1184. [PMID: 26967284 DOI: 10.1016/j.cell.2016.02.047] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Indexed: 12/12/2022]
Abstract
Cell signaling is dominated by analyzing positive responses to stimuli. Signal activation is balanced by negative regulators that are generally considered to terminate signaling. Rather than exerting only negative effects, however, many such regulators play important roles in enhancing cell-signaling control. Considering responses downstream of selected cell-surface receptors, we discuss how receptor internalization affects signaling specificity and how rapid kinase/phosphatase and GTP/GDP cycles increase responsiveness and allow kinetic proofreading in receptor signaling. We highlight the blurring of distinctions between positive and negative signals, recasting signal termination as the response to a switch-like transition into a new cellular state.
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Affiliation(s)
- Mark A Lemmon
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, West Haven, CT 06516, USA.
| | - Daniel M Freed
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, West Haven, CT 06516, USA
| | - Joseph Schlessinger
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, West Haven, CT 06516, USA
| | - Anatoly Kiyatkin
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, West Haven, CT 06516, USA
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67
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Offermann B, Knauer S, Singh A, Fernández-Cachón ML, Klose M, Kowar S, Busch H, Boerries M. Boolean Modeling Reveals the Necessity of Transcriptional Regulation for Bistability in PC12 Cell Differentiation. Front Genet 2016; 7:44. [PMID: 27148350 PMCID: PMC4830832 DOI: 10.3389/fgene.2016.00044] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 03/14/2016] [Indexed: 12/18/2022] Open
Abstract
The nerve growth factor NGF has been shown to cause cell fate decisions toward either differentiation or proliferation depending on the relative activity of downstream pERK, pAKT, or pJNK signaling. However, how these protein signals are translated into and fed back from transcriptional activity to complete cellular differentiation over a time span of hours to days is still an open question. Comparing the time-resolved transcriptome response of NGF- or EGF-stimulated PC12 cells over 24 h in combination with protein and phenotype data we inferred a dynamic Boolean model capturing the temporal sequence of protein signaling, transcriptional response and subsequent autocrine feedback. Network topology was optimized by fitting the model to time-resolved transcriptome data under MEK, PI3K, or JNK inhibition. The integrated model confirmed the parallel use of MAPK/ERK, PI3K/AKT, and JNK/JUN for PC12 cell differentiation. Redundancy of cell signaling is demonstrated from the inhibition of the different MAPK pathways. As suggested in silico and confirmed in vitro, differentiation was substantially suppressed under JNK inhibition, yet delayed only under MEK/ERK inhibition. Most importantly, we found that positive transcriptional feedback induces bistability in the cell fate switch. De novo gene expression was necessary to activate autocrine feedback that caused Urokinase-Type Plasminogen Activator (uPA) Receptor signaling to perpetuate the MAPK activity, finally resulting in the expression of late, differentiation related genes. Thus, the cellular decision toward differentiation depends on the establishment of a transcriptome-induced positive feedback between protein signaling and gene expression thereby constituting a robust control between proliferation and differentiation.
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Affiliation(s)
- Barbara Offermann
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg Freiburg, Germany
| | - Steffen Knauer
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg Freiburg, Germany
| | - Amit Singh
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg Freiburg, Germany
| | - María L Fernández-Cachón
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg Freiburg, Germany
| | - Martin Klose
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg Freiburg, Germany
| | - Silke Kowar
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg Freiburg, Germany
| | - Hauke Busch
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University FreiburgFreiburg, Germany; German Cancer ConsortiumFreiburg, Germany; German Cancer Research CenterHeidelberg, Germany
| | - Melanie Boerries
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University FreiburgFreiburg, Germany; German Cancer ConsortiumFreiburg, Germany; German Cancer Research CenterHeidelberg, Germany
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68
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Redefining Signaling Pathways with an Expanding Single-Cell Toolbox. Trends Biotechnol 2016; 34:458-469. [PMID: 26968612 DOI: 10.1016/j.tibtech.2016.02.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 02/12/2016] [Accepted: 02/16/2016] [Indexed: 01/12/2023]
Abstract
Genetically identical cells respond heterogeneously to uniform environmental stimuli. Consequently, investigating the signaling networks that control these cell responses using 'average' bulk cell measurements can obscure underlying mechanisms and misses information emerging from cell-to-cell variability. Here we review recent technological advances including live-cell fluorescence imaging-based approaches and microfluidic devices that enable measurements of signaling networks, dynamics, and responses in single cells. We discuss how these single-cell tools have uncovered novel mechanistic insights for canonical signaling pathways that control cell proliferation (ERK), DNA-damage responses (p53), and innate immune and stress responses (NF-κB). Future improvements in throughput and multiplexing, analytical pipelines, and in vivo applicability will all significantly expand the biological information gained from single-cell measurements of signaling pathways.
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69
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van Unen J, Stumpf AD, Schmid B, Reinhard NR, Hordijk PL, Hoffmann C, Gadella TWJ, Goedhart J. A New Generation of FRET Sensors for Robust Measurement of Gαi1, Gαi2 and Gαi3 Activation Kinetics in Single Cells. PLoS One 2016; 11:e0146789. [PMID: 26799488 PMCID: PMC4723041 DOI: 10.1371/journal.pone.0146789] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 12/22/2015] [Indexed: 01/14/2023] Open
Abstract
G-protein coupled receptors (GPCRs) can activate a heterotrimeric G-protein complex with subsecond kinetics. Genetically encoded biosensors based on Förster resonance energy transfer (FRET) are ideally suited for the study of such fast signaling events in single living cells. Here we report on the construction and characterization of three FRET biosensors for the measurement of Gαi1, Gαi2 and Gαi3 activation. To enable quantitative long-term imaging of FRET biosensors with high dynamic range, fluorescent proteins with enhanced photophysical properties are required. Therefore, we use the currently brightest and most photostable CFP variant, mTurquoise2, as donor fused to Gαi subunit, and cp173Venus fused to the Gγ2 subunit as acceptor. The Gαi FRET biosensors constructs are expressed together with Gβ1 from a single plasmid, providing preferred relative expression levels with reduced variation in mammalian cells. The Gαi FRET sensors showed a robust response to activation of endogenous or over-expressed alpha-2A-adrenergic receptors, which was inhibited by pertussis toxin. Moreover, we observed activation of the Gαi FRET sensor in single cells upon stimulation of several GPCRs, including the LPA2, M3 and BK2 receptor. Furthermore, we show that the sensors are well suited to extract kinetic parameters from fast measurements in the millisecond time range. This new generation of FRET biosensors for Gαi1, Gαi2 and Gαi3 activation will be valuable for live-cell measurements that probe Gαi activation.
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Affiliation(s)
- Jakobus van Unen
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
| | - Anette D Stumpf
- Bio-Imaging-Center/Rudolf-Virchow-Zentrum and Department of Pharmacology and Toxicology, University of Wuerzburg, Versbacher Strasse 9, 97078, Wuerzburg, Germany
| | - Benedikt Schmid
- Bio-Imaging-Center/Rudolf-Virchow-Zentrum and Department of Pharmacology and Toxicology, University of Wuerzburg, Versbacher Strasse 9, 97078, Wuerzburg, Germany
| | - Nathalie R Reinhard
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands.,Department of Molecular Cell Biology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, NL-1066 CX, Amsterdam, the Netherlands
| | - Peter L Hordijk
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands.,Department of Molecular Cell Biology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, NL-1066 CX, Amsterdam, the Netherlands
| | - Carsten Hoffmann
- Bio-Imaging-Center/Rudolf-Virchow-Zentrum and Department of Pharmacology and Toxicology, University of Wuerzburg, Versbacher Strasse 9, 97078, Wuerzburg, Germany
| | - Theodorus W J Gadella
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
| | - Joachim Goedhart
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
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70
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Ryu H, Chung M, Dobrzyński M, Fey D, Blum Y, Lee SS, Peter M, Kholodenko BN, Jeon NL, Pertz O. Frequency modulation of ERK activation dynamics rewires cell fate. Mol Syst Biol 2015; 11:838. [PMID: 26613961 PMCID: PMC4670727 DOI: 10.15252/msb.20156458] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Transient versus sustained ERK MAP kinase (MAPK) activation dynamics induce proliferation versus differentiation in response to epidermal (EGF) or nerve (NGF) growth factors in PC‐12 cells. Duration of ERK activation has therefore been proposed to specify cell fate decisions. Using a biosensor to measure ERK activation dynamics in single living cells reveals that sustained EGF/NGF application leads to a heterogeneous mix of transient and sustained ERK activation dynamics in distinct cells of the population, different than the population average. EGF biases toward transient, while NGF biases toward sustained ERK activation responses. In contrast, pulsed growth factor application can repeatedly and homogeneously trigger ERK activity transients across the cell population. These datasets enable mathematical modeling to reveal salient features inherent to the MAPK network. Ultimately, this predicts pulsed growth factor stimulation regimes that can bypass the typical feedback activation to rewire the system toward cell differentiation irrespective of growth factor identity.
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Affiliation(s)
- Hyunryul Ryu
- School of Mechanical and Aerospace Engineering Seoul National University, Seoul, Korea Institute of Advanced Machinery and Design Seoul National University, Seoul, Korea
| | - Minhwan Chung
- School of Mechanical and Aerospace Engineering Seoul National University, Seoul, Korea
| | - Maciej Dobrzyński
- System Biology Ireland, University College Dublin, Belfield Dublin, Ireland
| | - Dirk Fey
- System Biology Ireland, University College Dublin, Belfield Dublin, Ireland
| | - Yannick Blum
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | | | | | - Boris N Kholodenko
- System Biology Ireland, University College Dublin, Belfield Dublin, Ireland
| | - Noo Li Jeon
- School of Mechanical and Aerospace Engineering Seoul National University, Seoul, Korea Institute of Advanced Machinery and Design Seoul National University, Seoul, Korea
| | - Olivier Pertz
- Department of Biomedicine, University of Basel, Basel, Switzerland
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