1
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Murthy MHS, Jasbi P, Lowe W, Kumar L, Olaosebikan M, Roger L, Yang J, Lewinski N, Daniels N, Cowen L, Klein-Seetharaman J. Insulin signaling and pharmacology in humans and in corals. PeerJ 2024; 12:e16804. [PMID: 38313028 PMCID: PMC10838073 DOI: 10.7717/peerj.16804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 12/27/2023] [Indexed: 02/06/2024] Open
Abstract
Once thought to be a unique capability of the Langerhans islets in the pancreas of mammals, insulin (INS) signaling is now recognized as an evolutionarily ancient function going back to prokaryotes. INS is ubiquitously present not only in humans but also in unicellular eukaryotes, fungi, worms, and Drosophila. Remote homologue identification also supports the presence of INS and INS receptor in corals where the availability of glucose is largely dependent on the photosynthetic activity of the symbiotic algae. The cnidarian animal host of corals operates together with a 20,000-sized microbiome, in direct analogy to the human gut microbiome. In humans, aberrant INS signaling is the hallmark of metabolic disease, and is thought to play a major role in aging, and age-related diseases, such as Alzheimer's disease. We here would like to argue that a broader view of INS beyond its human homeostasis function may help us understand other organisms, and in turn, studying those non-model organisms may enable a novel view of the human INS signaling system. To this end, we here review INS signaling from a new angle, by drawing analogies between humans and corals at the molecular level.
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Affiliation(s)
| | - Paniz Jasbi
- School of Molecular Sciences, Arizona State University, Phoenix, AZ, USA
| | - Whitney Lowe
- Departments of Chemistry & Physics, Colorado School of Mines, Golden, CO, United States
| | - Lokender Kumar
- Departments of Chemistry & Physics, Colorado School of Mines, Golden, CO, United States
| | | | - Liza Roger
- School of Molecular Sciences, Arizona State University, Phoenix, AZ, USA
- School of Ocean Futures, Arizona State University, Tempe, AZ, United States of America
| | - Jinkyu Yang
- Department of Aeronautics & Astronautics, University of Washington, Seattle, WA, USA
| | - Nastassja Lewinski
- Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Noah Daniels
- Department of Computer Science, University of Rhode Island, Kingston, RI, USA
| | - Lenore Cowen
- Department of Computer Science, Tufts University, Medford, MA, USA
| | - Judith Klein-Seetharaman
- School of Molecular Sciences, Arizona State University, Phoenix, AZ, USA
- Departments of Chemistry & Physics, Colorado School of Mines, Golden, CO, United States
- College of Health Solutions, Arizona State University, Phoenix, AZ, United States
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2
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He L, Cohen EB, Edwards APB, Xavier-Ferrucio J, Bugge K, Federman RS, Absher D, Myers RM, Kragelund BB, Krause DS, DiMaio D. Transmembrane Protein Aptamer Induces Cooperative Signaling by the EPO Receptor and the Cytokine Receptor β-Common Subunit. iScience 2019; 17:167-181. [PMID: 31279934 PMCID: PMC6614117 DOI: 10.1016/j.isci.2019.06.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 05/10/2019] [Accepted: 06/17/2019] [Indexed: 12/13/2022] Open
Abstract
The erythropoietin receptor (EPOR) plays an essential role in erythropoiesis and other cellular processes by forming distinct signaling complexes composed of EPOR homodimers or hetero-oligomers between the EPOR and another receptor, but the mechanism of heteroreceptor assembly and signaling is poorly understood. We report here a 46-residue, artificial transmembrane protein aptamer, designated ELI-3, that binds and activates the EPOR and induces growth factor independence in murine BaF3 cells expressing the EPOR. ELI-3 requires the transmembrane domain and JAK2-binding sites of the EPOR for activity, but not the cytoplasmic tyrosines that mediate canonical EPOR signaling. Instead, ELI-3-induced proliferation and activation of JAK/STAT signaling requires the transmembrane and cytoplasmic domains of the cytokine receptor β-common subunit (βcR) in addition to the EPOR. Moreover, ELI-3 fails to induce erythroid differentiation of primary human hematopoietic progenitor cells but inhibits nonhematopoietic cell death induced by serum withdrawal.
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Affiliation(s)
- Li He
- Department of Genetics, Yale School of Medicine, P.O. Box 208005, New Haven, CT 06520-8005, USA
| | - Emily B Cohen
- Department of Genetics, Yale School of Medicine, P.O. Box 208005, New Haven, CT 06520-8005, USA
| | - Anne P B Edwards
- Department of Genetics, Yale School of Medicine, P.O. Box 208005, New Haven, CT 06520-8005, USA
| | - Juliana Xavier-Ferrucio
- Department of Laboratory Medicine, Yale School of Medicine, P.O. Box 208073, New Haven, CT 06520-8073, USA
| | - Katrine Bugge
- Structural Biology and NMR Laboratory, The Linderstrøm-Lang Centre for Protein Science and Integrative Structural Biology at University of Copenhagen (ISBUC), Department of Biology, University of Copenhagen, Copenhagen N 2200, Denmark
| | - Ross S Federman
- Department of Immunobiology, Yale School of Medicine, P.O. Box 208011, New Haven, CT 06520-8011, USA
| | - Devin Absher
- HudsonAlpha Institute for Biotechnology, 601 Genome Way, Huntsville, AL 35806, USA
| | - Richard M Myers
- HudsonAlpha Institute for Biotechnology, 601 Genome Way, Huntsville, AL 35806, USA
| | - Birthe B Kragelund
- Structural Biology and NMR Laboratory, The Linderstrøm-Lang Centre for Protein Science and Integrative Structural Biology at University of Copenhagen (ISBUC), Department of Biology, University of Copenhagen, Copenhagen N 2200, Denmark
| | - Diane S Krause
- Department of Laboratory Medicine, Yale School of Medicine, P.O. Box 208073, New Haven, CT 06520-8073, USA; Yale Cancer Center, P.O. Box 208028, New Haven, CT 06520-8028, USA
| | - Daniel DiMaio
- Department of Genetics, Yale School of Medicine, P.O. Box 208005, New Haven, CT 06520-8005, USA; Department of Therapeutic Radiology, Yale School of Medicine, P.O. Box 208040, New Haven, CT 06520-8040, USA; Department of Molecular Biophysics & Biochemistry, P.O. Box 208114, Yale University, New Haven, CT 06520-8114, USA; Yale Cancer Center, P.O. Box 208028, New Haven, CT 06520-8028, USA.
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3
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Ferrao R, Lupardus PJ. The Janus Kinase (JAK) FERM and SH2 Domains: Bringing Specificity to JAK-Receptor Interactions. Front Endocrinol (Lausanne) 2017; 8:71. [PMID: 28458652 PMCID: PMC5394478 DOI: 10.3389/fendo.2017.00071] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 03/27/2017] [Indexed: 12/24/2022] Open
Abstract
The Janus kinases (JAKs) are non-receptor tyrosine kinases essential for signaling in response to cytokines and interferons and thereby control many essential functions in growth, development, and immune regulation. JAKs are unique among tyrosine kinases for their constitutive yet non-covalent association with class I and II cytokine receptors, which upon cytokine binding bring together two JAKs to create an active signaling complex. JAK association with cytokine receptors is facilitated by N-terminal FERM and SH2 domains, both of which are classical mediators of peptide interactions. Together, the JAK FERM and SH2 domains mediate a bipartite interaction with two distinct receptor peptide motifs, the proline-rich "Box1" and hydrophobic "Box2," which are present in the intracellular domain of cytokine receptors. While the general sidechain chemistry of Box1 and Box2 peptides is conserved between receptors, they share very weak primary sequence homology, making it impossible to posit why certain JAKs preferentially interact with and signal through specific subsets of cytokine receptors. Here, we review the structure and function of the JAK FERM and SH2 domains in light of several recent studies that reveal their atomic structure and elucidate interaction mechanisms with both the Box1 and Box2 receptor motifs. These crystal structures demonstrate how evolution has repurposed the JAK FERM and SH2 domains into a receptor-binding module that facilitates interactions with multiple receptors possessing diverse primary sequences.
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Affiliation(s)
- Ryan Ferrao
- Department of Structural Biology, Genentech Inc., South San Francisco, CA, USA
| | - Patrick J. Lupardus
- Department of Structural Biology, Genentech Inc., South San Francisco, CA, USA
- *Correspondence: Patrick J. Lupardus,
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4
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Watowich SS. The erythropoietin receptor: molecular structure and hematopoietic signaling pathways. J Investig Med 2012; 59:1067-72. [PMID: 21307776 DOI: 10.2310/jim.0b013e31820fb28c] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The process of erythropoiesis in the fetal liver and adult bone marrow is regulated by the hormone erythropoietin (Epo), which is produced in the kidney at low levels under homeostatic conditions. Defects in Epo production result in severe anemia; use of recombinant hormone has improved the lives of patients with renal failure or anemia because of bone marrow suppression. Deletion of the Epo gene in mice leads to embryonic lethality at days 13 to 15, coincident with the establishment of definitive (adult-type) erythropoiesis and underscoring the absolute necessity of Epo function in vivo. Epo has proven to be a successful pharmaceutical agent, one of the early triumphs of recombinant protein technology. Because of its clinical importance, a great deal of attention has focused on the molecular mechanisms of Epo-regulated erythropoiesis. This review highlights the basic concepts of Epo signal transduction within the hematopoietic system, the major site of Epo action in vivo.
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Affiliation(s)
- Stephanie S Watowich
- Department of Immunology and Center for Inflammation and Cancer, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA.
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5
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Watowich SS. The erythropoietin receptor: molecular structure and hematopoietic signaling pathways. J Investig Med 2011; 59. [PMID: 21307776 PMCID: PMC3134576 DOI: 10.231/jim.0b013e31820fb28c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The process of erythropoiesis in the fetal liver and adult bone marrow is regulated by the hormone erythropoietin (Epo), which is produced in the kidney at low levels under homeostatic conditions. Defects in Epo production result in severe anemia; use of recombinant hormone has improved the lives of patients with renal failure or anemia because of bone marrow suppression. Deletion of the Epo gene in mice leads to embryonic lethality at days 13 to 15, coincident with the establishment of definitive (adult-type) erythropoiesis and underscoring the absolute necessity of Epo function in vivo. Epo has proven to be a successful pharmaceutical agent, one of the early triumphs of recombinant protein technology. Because of its clinical importance, a great deal of attention has focused on the molecular mechanisms of Epo-regulated erythropoiesis. This review highlights the basic concepts of Epo signal transduction within the hematopoietic system, the major site of Epo action in vivo.
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Affiliation(s)
- Stephanie S. Watowich
- Department of Immunology and Center for Inflammation and Cancer, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA,The Graduate School of Biomedical Sciences, The University of Texas, Houston, Texas 77030, USA
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6
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Involvement of phosphatases in proliferation, maturation, and hemoglobinization of developing erythroid cells. JOURNAL OF SIGNAL TRANSDUCTION 2011; 2011:860985. [PMID: 21785724 PMCID: PMC3139203 DOI: 10.1155/2011/860985] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 04/11/2011] [Accepted: 05/04/2011] [Indexed: 12/16/2022]
Abstract
Production of RBCs is triggered by the action of erythropoietin (Epo) through its binding to surface receptors
(Epo-R) on erythroid precursors in the bone marrow. The intensity and the duration of the Epo signal are regulated by several factors,
including the balance between the activities of kinesase and phosphatases. The Epo signal determines the proliferation and maturation
of the precursors into hemoglobin (Hb)-containing RBCs. The activity of various protein tyrosine phosphatases, including those involved in the
Epo pathway, can be inhibited by sodium orthovanadate (Na3VO4, vanadate). Adding vanadate to cultured erythroid precursors of normal
donors and patients with β-thalassemia enhanced cell proliferation and arrested maturation. This was associated with an increased production
of fetal hemoglobin (HbF). Increased HbF in patients with β-hemoglobinopathies (β-thalassemia and sickle cell disease) ameliorates the clinical
symptoms of the disease. These results raise the possibility that specific and nontoxic inhibitors of phosphatases may be considered as a
therapeutic modality for elevating HbF in patients with β-hemoglobinopathies
as well as for intensifying the Epo response in other forms of anemia.
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7
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Haan C, Behrmann I, Haan S. Perspectives for the use of structural information and chemical genetics to develop inhibitors of Janus kinases. J Cell Mol Med 2010; 14:504-27. [PMID: 20132407 PMCID: PMC3823453 DOI: 10.1111/j.1582-4934.2010.01018.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Gain-of-function mutations in the genes encoding Janus kinases have been discovered in various haematologic diseases. Jaks are composed of a FERM domain, an SH2 domain, a pseudokinase domain and a kinase domain, and a complex interplay of the Jak domains is involved in regulation of catalytic activity and association to cytokine receptors. Most activating mutations are found in the pseudokinase domain. Here we present recently discovered mutations in the context of our structural models of the respective domains. We describe two structural hotspots in the pseudokinase domain of Jak2 that seem to be associated either to myeloproliferation or to lymphoblastic leukaemia, pointing at the involvement of distinct signalling complexes in these disease settings. The different domains of Jaks are discussed as potential drug targets. We present currently available inhibitors targeting Jaks and indicate structural differences in the kinase domains of the different Jaks that may be exploited in the development of specific inhibitors. Moreover, we discuss recent chemical genetic approaches which can be applied to Jaks to better understand the role of these kinases in their biological settings and as drug targets.
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Affiliation(s)
- Claude Haan
- Life Sciences Research Unit, University of Luxembourg, 162A, av. de la Faïencerie, 1511 Luxembourg, Luxembourg.
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8
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Royer Y, Staerk J, Costuleanu M, Courtoy PJ, Constantinescu SN. Janus Kinases Affect Thrombopoietin Receptor Cell Surface Localization and Stability. J Biol Chem 2005; 280:27251-61. [PMID: 15899890 DOI: 10.1074/jbc.m501376200] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The thrombopoietin receptor (TpoR) regulates hematopoietic stem cell renewal, megakaryocyte differentiation, and platelet formation. TpoR signals by activating Janus kinases JAK2 and Tyk2. Here we show that, in addition to signaling downstream from the activated TpoR, JAK2 and Tyk2 strongly promote cell surface localization and enhance total protein levels of the TpoR. This effect is caused by stabilization of the mature endoglycosidase H-resistant form of the receptor. Confocal microscopy indicates that TpoR colocalizes partially with recycling transferrin in Ba/F3 cells. The interaction with JAK2 or Tyk2 appears to protect the receptor from proteasome degradation. Sequences encompassing Box1 and Box2 regions of the receptor cytosolic domain and an intact JAK2 or Tyk2 FERM domain are required for these effects. We discuss the relevance of our results to the reported defects of TpoR processing in myeloproliferative diseases and to the mechanisms of Tpo signaling and clearance via the TpoR.
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Affiliation(s)
- Yohan Royer
- Ludwig Institute for Cancer Research, Brussels B-1200, Belgium
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9
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Sigalov A, Aivazian D, Stern L. Homooligomerization of the cytoplasmic domain of the T cell receptor zeta chain and of other proteins containing the immunoreceptor tyrosine-based activation motif. Biochemistry 2004; 43:2049-61. [PMID: 14967045 DOI: 10.1021/bi035900h] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Antigen receptors on T cells, B cells, mast cells, and basophils all have cytoplasmic domains containing one or more copies of an immunoreceptor tyrosine-based activation motif (ITAM), tyrosine residues of which are phosphorylated upon receptor engagement in an early and obligatory event in the signaling cascade. How clustering of receptor extracellular domains leads to phosphorylation of cytoplasmic domain ITAMs is not known, and little structural or biochemical information is available for the ITAM-containing cytoplasmic domains. Here we investigate the conformation and oligomeric state of several immune receptor cytoplasmic domains, using purified recombinant proteins and a variety of biophysical and biochemical techniques. We show that all of the cytoplasmic domains of ITAM-containing signaling subunits studied are oligomeric in solution, namely, T cell antigen receptor zeta, CD3epsilon, CD3delta, and CD3gamma, B cell antigen receptor Igalpha and Igbeta, and Fc receptor FcepsilonRIgamma. For zeta(cyt), the oligomerization behavior is best described by a two-step monomer-dimer-tetramer fast dynamic equilibrium with dissociation constants in the order of approximately 10 microM (monomer-dimer) and approximately 1 mM (dimer-tetramer). In contrast to the other ITAM-containing proteins, Igalpha(cyt) forms stable dimers and tetramers even below 10 microM. Circular dichroic analysis reveals the lack of stable ordered structure of the cytoplasmic domains studied, and oligomerization does not change the random-coil-like conformation observed. The random-coil nature of zeta(cyt) was also confirmed by heteronuclear NMR. Phosphorylation of zeta(cyt) and FcepsilonRIgamma(cyt) does not significantly alter their oligomerization behavior. The implications of these results for transmembrane signaling and cellular activation by immune receptors are discussed.
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MESH Headings
- Amino Acid Motifs
- Chromatography, Gel
- Cross-Linking Reagents/chemistry
- Cytoplasm/chemistry
- Cytoplasm/metabolism
- Dimerization
- Escherichia coli/genetics
- Humans
- Light
- Lymphocyte Activation
- Membrane Proteins/biosynthesis
- Membrane Proteins/chemistry
- Membrane Proteins/genetics
- Membrane Proteins/isolation & purification
- Nuclear Magnetic Resonance, Biomolecular
- Phosphorylation
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Receptors, Antigen, T-Cell/biosynthesis
- Receptors, Antigen, T-Cell/chemistry
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/isolation & purification
- Recombinant Proteins/biosynthesis
- Recombinant Proteins/chemistry
- Recombinant Proteins/isolation & purification
- Recombinant Proteins/metabolism
- Scattering, Radiation
- Solutions
- Temperature
- Thermodynamics
- Tyrosine/chemistry
- Tyrosine/metabolism
- Ultracentrifugation
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Affiliation(s)
- Alexander Sigalov
- Department of Pathology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655, USA.
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10
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Yoon D, Watowich SS. Hematopoietic cell survival signals are elicited through non-tyrosine-containing sequences in the membrane-proximal region of the erythropoietin receptor (EPOR) by a Stat5-dependent pathway. Exp Hematol 2004; 31:1310-6. [PMID: 14662339 PMCID: PMC2388246 DOI: 10.1016/j.exphem.2003.08.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
OBJECTIVE Erythropoietin is essential for red blood cell development in vivo and is also an important therapeutic agent to treat anemia resulting from kidney failure or bone marrow suppression. The erythropoietin receptor (EPOR) elicits both positive and negative regulatory signaling pathways, primarily through phosphorylated tyrosine residues in the cytoplasmic domain of the activated receptor complex. Surprisingly, however, EPOR tyrosine residues are dispensable for in vivo erythropoiesis under nonstress conditions. One of the key signaling molecules elicited by the EPOR is the Stat5 transcription factor. Stat5 activation has been mapped to tyrosines 343 and 401 in the EPOR cytoplasmic region, although non-tyrosine-containing sequences in the EPOR cytoplasmic region can also stimulate Stat5. To test the functional role of non-tyrosine-containing sequences in the EPOR, we analyzed a series of mutant EPOR isoforms in cell survival and proliferation assays. METHODS The IL-3-dependent 32D cell line was stably transfected with cDNAs encoding the wild-type EPOR or mutant EPORs containing or lacking intracellular tyrosines, in the absence or presence of a dominant inhibitory Stat5 isoform. EPO-dependent cell signaling, survival, and proliferation were evaluated. RESULTS EPOR isoforms lacking intracellular tyrosine residues elicit an important survival signal in 32D cells. Stat5 function is critical for EPO-dependent cell survival mediated by these non-tyrosine-containing receptor sequences. Interestingly, EPO-dependent survival does not require the presence of fetal calf serum (FCS) in the culture medium, yet FCS is important for 32D cell proliferation in response to EPO. CONCLUSION Our results elucidate a previously unrecognized survival pathway elicited by the EPOR. They demonstrate that this pathway requires Stat5 and is serum independent. These findings contribute significantly to our understanding of the complexity by which the EPOR functions in hematopoietic cells.
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Affiliation(s)
- Donghoon Yoon
- Department of Immunology, The University of Texas MD Anderson Cancer Center, and Graduate School of Biomedical Sciences, Houston, TX 77030, USA
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11
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Arcasoy MO, Jiang X, Haroon ZA. Expression of erythropoietin receptor splice variants in human cancer. Biochem Biophys Res Commun 2003; 307:999-1007. [PMID: 12878211 DOI: 10.1016/s0006-291x(03)01303-2] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Erythropoietin (EPO) regulates mammalian erythropoiesis by binding to its transmembrane receptor EPOR. Recent studies demonstrated functional EPOR expression in human cancer cells. Recombinant human EPO was reported to stimulate the proliferation of monolayer cultures of breast and renal carcinoma cells. Furthermore, administration of EPO-EPOR antagonists delayed the growth of uterine, ovarian, and mammary carcinoma cells in experimental animal models. In this study, we show EPOR transcript and protein expression in breast, colon, lung, ovary, and prostate cancer cells. Using reverse transcription-polymerase chain reaction, we isolated and characterized several novel cDNAs for EPOR splice variants expressed in cancer cells. Deduced amino acid sequences of the cDNAs revealed splice variants encoding soluble EPOR or membrane-bound EPOR peptides with intra-cytoplasmic, carboxy-terminal truncations. These findings indicate the expression of multiple EPOR isoforms in human cancer cells that may modulate the cellular effects of recombinant human EPO or EPO-EPOR antagonists.
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Affiliation(s)
- Murat O Arcasoy
- Department of Medicine, Division of Hematology-Medical Oncology, Duke University School of Medicine, DUMC Box 3912, Durham, NC 27710, USA.
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12
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Lindemann MJ, Benczik M, Gaffen SL. Anti-apoptotic signaling by the interleukin-2 receptor reveals a function for cytoplasmic tyrosine residues within the common gamma (gamma c) receptor subunit. J Biol Chem 2003; 278:10239-49. [PMID: 12525482 DOI: 10.1074/jbc.m209471200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The interleukin-2 receptor (IL-2R) is composed of one affinity-modulating subunit (IL-2Ralpha) and two essential signaling subunits (IL-2Rbeta and gammac). Although most known signaling events are mediated through tyrosine residues located within IL-2Rbeta, no functions have yet been ascribed to gammac tyrosine residues. In this study, we describe a role for gammac tyrosines in anti-apoptotic signal transduction. We have shown previously that a tyrosine-deficient IL-2Rbeta chain paired with wild type gammac stimulated enhancement of bcl-2 mRNA in IL-2-dependent T cells, but it was not determined which region of the IL-2R or which pathway was activated to direct this signaling response. Here we show that up-regulation of Bcl-2 by an IL-2R lacking IL-2Rbeta tyrosine residues leads to increased cell survival after cytokine deprivation; strikingly, this survival signal does not occur in the absence of gammac tyrosine residues. These gammac-dependent signals are revealed only in the absence of IL-2Rbeta tyrosines, indicating that the IL-2R engages at least two distinct signaling pathways to regulate apoptosis and Bcl-2 expression. Mechanistically, the gammac-dependent signal requires activation of Janus kinases 1 and 3 and is sensitive to wortmannin, implicating phosphatidylinositol 3-kinase. Consistent with involvement of phosphatidylinositol 3-kinase, Akt can be activated via tyrosine residues on gammac. Thus, gammac mediates an anti-apoptotic signaling pathway through Akt which cooperates with signals from its partner chain, IL-2Rbeta.
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Affiliation(s)
- Matthew J Lindemann
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
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13
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Blake TJ, Jenkins BJ, D’Andrea RJ, Gonda TJ. Functional cross‐talk between cytokine receptors revealed by activating mutations in the extracellular domain of the β‐subunit of the GM‐CSF receptor. J Leukoc Biol 2002. [DOI: 10.1189/jlb.72.6.1246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Timothy J. Blake
- Hanson Institute, Division of Human Immunology, Institute of Medical and Veterinary Science, Adelaide, and Department of Medicine, Adelaide University, South Australia
| | - Brendan J. Jenkins
- Hanson Institute, Division of Human Immunology, Institute of Medical and Veterinary Science, Adelaide, and Department of Medicine, Adelaide University, South Australia
| | - Richard J. D’Andrea
- Hanson Institute, Division of Human Immunology, Institute of Medical and Veterinary Science, Adelaide, and Department of Medicine, Adelaide University, South Australia
| | - Thomas J. Gonda
- Hanson Institute, Division of Human Immunology, Institute of Medical and Veterinary Science, Adelaide, and Department of Medicine, Adelaide University, South Australia
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14
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Yu X, Shacka JJ, Eells JB, Suarez-Quian C, Przygodzki RM, Beleslin-Cokic B, Lin CS, Nikodem VM, Hempstead B, Flanders KC, Costantini F, Noguchi CT. Erythropoietin receptor signalling is required for normal brain development. Development 2002; 129:505-16. [PMID: 11807041 DOI: 10.1242/dev.129.2.505] [Citation(s) in RCA: 269] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Erythropoietin, known for its role in erythroid differentiation, has been shown to be neuroprotective during brain ischaemia in adult animal models. Although high levels of erythropoietin receptor are produced in embryonic brain, the role of erythropoietin during brain development is uncertain. We now provide evidence that erythropoietin acts to stimulate neural progenitor cells and to prevent apoptosis in the embryonic brain. Mice lacking the erythropoietin receptor exhibit severe anaemia and defective cardiac development, and die at embryonic day 13.5 (E13.5). By E12.5, in addition to apoptosis in foetal liver, endocardium and myocardium, the erythropoietin receptor null mouse shows extensive apoptosis in foetal brain. Lack of erythropoietin receptor affects brain development as early as E10.5, resulting in a reduction in the number of neural progenitor cells and increased apoptosis. Corresponding in vitro cultures of cortical cells from Epor–/– mice also exhibited decreases in neuron generation compared with normal controls and increased sensitivity to low oxygen tension with no surviving neurons in Epor–/– cortical cultures after 24 hour exposure to hypoxia. The viability of primary Epor+/+ rodent embryonic cortical neurons was further increased by erythropoietin stimulation. Exposure of these cultures to hypoxia induced erythropoietin expression and a tenfold increase in erythropoietin receptor expression, increased cell survival and decreased apoptosis. Cultures of neuronal progenitor cells also exhibited a proliferative response to erythropoietin stimulation. These data demonstrate that the neuroprotective activity of erythropoietin is observed as early as E10.5 in the developing brain, and that induction of erythropoietin and its receptor by hypoxia may contribute to selective cell survival in the brain.
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Affiliation(s)
- Xiaobing Yu
- Laboratory of Chemical Biology, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
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15
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Haan C, Heinrich PC, Behrmann I. Structural requirements of the interleukin-6 signal transducer gp130 for its interaction with Janus kinase 1: the receptor is crucial for kinase activation. Biochem J 2002; 361:105-11. [PMID: 11742534 PMCID: PMC1222284 DOI: 10.1042/0264-6021:3610105] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We analysed the interaction of gp130, the common signal-transducing receptor chain of interleukin (IL)-6 type cytokines, with Jak1, the Janus family kinase which is crucial for signal transduction of this group of cytokines. With a truncated chimaeric IL-5Rbeta-gp130 receptor expressed in COS-7 cells, we show that the membrane-proximal 69 amino acids are sufficient to mediate Jak1 binding and activation. Deletion of box2 drastically reduced binding of endogenous, but not of overexpressed, Jak1. Several point mutations in the membrane-proximal region of gp130 (W652A, P671/P672A, F676A, Y683F, where W, A, P, F and Y are tryptophan, alanine, proline, phenylalanine and tyrosine) did not affect Jak1 association. However, stimulation of chimaeric receptors with the mutations P671/P672A and F676A in the interbox1/box2 region resulted in a reduced activation of STAT (signal transducer and activator of transcription) transcription factors. Most importantly, signalling by the receptor with the box1 mutation W652A was totally abrogated. Although this mutation did not affect Jak1 association, stimulation-dependent phosphorylation of Jak1 was prevented. The W652 mutation acts dominantly, since no signalling occured even when only a single cytoplasmic chain of a gp130 dimer contained the mutation. Our data demonstrate that the mere proximity of Jaks in an activated receptor complex is not sufficient to mediate their activation. Rather, it seems that parts of the receptor, including the box1 region, are involved in positioning Jaks correctly so that ligand-induced receptor dimerization and reorientation can lead to their mutual activation and subsequently to downstream signalling events.
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Affiliation(s)
- Claude Haan
- Department of Biochemistry, Rheinisch-Westfälische Technische Hochschule, Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany
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16
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Ogilvie M, Yu X, Nicolas-Metral V, Pulido SM, Liu C, Ruegg UT, Noguchi CT. Erythropoietin stimulates proliferation and interferes with differentiation of myoblasts. J Biol Chem 2000; 275:39754-61. [PMID: 10995753 DOI: 10.1074/jbc.m004999200] [Citation(s) in RCA: 191] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Erythropoietin (Epo) is required for the production of mature red blood cells. The requirement for Epo and its receptor (EpoR) for normal heart development and the response of vascular endothelium and cells of neural origin to Epo provide evidence that the function of Epo as a growth factor or cytokine to protect cells from apoptosis extends beyond the hematopoietic lineage. We now report that the EpoR is expressed on myoblasts and can mediate a biological response of these cells to treatment with Epo. Primary murine satellite cells and myoblast C2C12 cells, both of which express endogenous EpoR, exhibit a proliferative response to Epo and a marked decrease in terminal differentiation to form myotubes. We also observed that Epo stimulation activates Jak2/Stat5 signal transduction and increases cytoplasmic calcium, which is dependent on tyrosine phosphorylation. In erythroid progenitor cells, Epo stimulates induction of transcription factor GATA-1 and EpoR; in C2C12 cells, GATA-3 and EpoR expression are induced. The decrease in differentiation of C2C12 cells is concomitant with an increase in Myf-5 and MyoD expression and inhibition of myogenin induction during differentiation, altering the pattern of expression of the MyoD family of transcription factors during muscle differentiation. These data suggest that, rather than acting in an instructive or specific mode for differentiation, Epo can stimulate proliferation of myoblasts to expand the progenitor population during differentiation and may have a potential role in muscle development or repair.
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Affiliation(s)
- M Ogilvie
- Laboratory of Chemical Biology, NIDDK, National Institutes of Health, Bethesda, Maryland 20892-1822, USA
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17
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Watowich SS, Mikami A, Busche RA, Xie X, Pharr PN, Longmore GD. Erythropoietin receptors that signal through Stat5 or Stat3 support fetal liver and adult erythropoiesis: lack of specificity of stat signals during red blood cell development. J Interferon Cytokine Res 2000; 20:1065-70. [PMID: 11152572 PMCID: PMC2422832 DOI: 10.1089/107999000750053726] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Erythropoietin (Epo) is essential for formation of mature red blood cells (RBC). However, the function of Epo receptor (EpoR)-dependent signaling pathways in the regulation of erythropoiesis remains unclear. To determine whether specific Stat signals are required for RBC development, we changed the Stat signaling specificity of the EpoR. The wild-type EpoR activates only Stat5. Thus, we substituted the major Stat5 binding sites (residues 343 and 401) in the EpoR cytoplasmic region with the Stat3 binding/activation motif from gp130. We demonstrated that activated EpoRs containing a single substitution stimulate Stat5 and Stat3, whereas an EpoR with both substitutions stimulates Stat3 but not Stat5. We then determined the ability of these receptors to support fetal liver and adult erythropoiesis. Our results show that erythropoiesis is stimulated by EpoRs that activate Stat5, both Stat5 and Stat3, or Stat3 in place of Stat5. These findings demonstrate that the specificity of EpoR Stat signaling is not essential for RBC development.
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Affiliation(s)
- S S Watowich
- Department of Immunology, MD Anderson Cancer Center, Houston, TX 77030, USA.
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18
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Wooten DK, Xie X, Bartos D, Busche RA, Longmore GD, Watowich SS. Cytokine signaling through Stat3 activates integrins, promotes adhesion, and induces growth arrest in the myeloid cell line 32D. J Biol Chem 2000; 275:26566-75. [PMID: 10858439 PMCID: PMC2396147 DOI: 10.1074/jbc.m003495200] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Hematopoietic cell development and function is dependent on cytokines and on intercellular interactions with the microenvironment. Although the intracellular signaling pathways stimulated by cytokine receptors are well described, little is known about the mechanisms through which these pathways modulate hematopoietic cell adhesion events in the microenvironment. Here we show that cytokine-activated Stat3 stimulates the expression and function of cell surface adhesion molecules in the myeloid progenitor cell line 32D. We generated an erythropoietin receptor (EpoR) isoform (ER343/401-S3) that activates Stat3 rather than Stat5 by substituting the Stat3 binding/activation sequence motif from gp130 for the sequences surrounding tyrosines 343 and 401 in the receptor cytoplasmic region. Activation of Stat3 leads to homotypic cell aggregation, increased expression of intercellular adhesion molecule 1 (ICAM-1), CD18, and CD11b, and activation of signaling through CD18-containing integrins. Unlike the wild type EpoR, ER343/401-S3 is unable to support long term Epo-dependent proliferation in 32D cells. Instead, Epo-treated ER343/401-S3 cells undergo G(1) arrest and express elevated levels of the cyclin-dependent kinase inhibitor p27(Kip1). Sustained activation of Stat3 in these cells is required for their altered morphology and growth properties since constitutive SOCS3 expression abrogates homotypic cell aggregation, signaling through CD18-containing integrins, G(1) arrest, and accumulation of p27(Kip1). Collectively, our results demonstrate that cytokine-activated Stat3 stimulates the expression and function of cell surface adhesion molecules, indicating that a role for Stat3 is to regulate intercellular contacts in myeloid cells.
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Affiliation(s)
- David K. Wooten
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Xiaoling Xie
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - David Bartos
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Ruth A. Busche
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Gregory D. Longmore
- Departments of Medicine and Cell Biology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Stephanie S. Watowich
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030
- To whom correspondence should be addressed: The University of Texas MD Anderson Cancer Center, Box 178, 1515 Holcombe Blvd., Houston, TX 77030. Tel.: 713-792-8376; Fax: 713-794-1322; E-mail:
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19
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Haan C, Hermanns HM, Heinrich PC, Behrmann I. A single amino acid substitution (Trp(666)-->Ala) in the interbox1/2 region of the interleukin-6 signal transducer gp130 abrogates binding of JAK1, and dominantly impairs signal transduction. Biochem J 2000; 349:261-6. [PMID: 10861237 PMCID: PMC1221146 DOI: 10.1042/0264-6021:3490261] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
gp130 is the common signal-transducing receptor chain of interleukin (IL)-6-type cytokines. Here we describe, for the first time, a single amino acid substitution (Trp(666)-->Ala) in the membrane-proximal interbox1/2 region that abrogates activation of STAT (signal transducer and activator of transcription) transcription factors and the proliferative response of pro-B-cell transfectants. Moreover, association of the Janus kinase JAK1 is prevented. No signalling of heterodimeric IL-5 receptor (IL-5R)/gp130 chimaeras occurs in COS-7 cells, even when only a single cytoplasmic chain of a gp130 dimer contains the Trp(666)Ala mutation, indicating that it acts dominantly.
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Affiliation(s)
- C Haan
- Department of Biochemistry, RWTH Aachen, Pauwelsstr. 30, 52074 Aachen, Germany
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20
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Pearson PL, Smith TP, Sonstegard TS, Klemcke HG, Christenson RK, Vallet JL. Porcine erythropoietin receptor: molecular cloning and expression in embryonic and fetal liver. Domest Anim Endocrinol 2000; 19:25-38. [PMID: 10962196 DOI: 10.1016/s0739-7240(00)00062-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The full coding sequence for porcine erythropoietin receptor (EPOR) was elucidated using reverse transcription polymerase chain reaction (PCR) (rtPCR) and 3' and 5' rapid amplification of cDNA ends (RACE) procedures. Total RNA collected from Day 30 fetal liver was used as starting material. A 1843 bp sequence was obtained from which could be inferred a 509 amino acid protein which was 79-85% identical to the amino acid sequence of erythropoietin receptor from other species. Total RNA samples collected from white crossbred intact, white crossbred UHO and Meishan gilts on Days 24, 30 and 40 of gestation were subjected to Northern blotting using porcine EPOR cDNA as probe. Results indicated that (1) a major and two minor forms of mRNA are present, (2) fetal liver mRNA concentrations for EPOR are low on Day 24 of gestation and increase dramatically by Day 30 and (3) mRNA concentrations for EPOR tended to be decreased by intrauterine crowding.
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Affiliation(s)
- P L Pearson
- USDA, ARS, Roman L. Hruska US Meat Animal Research Center, Clay Center, NE 68933, USA
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21
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Cull V, Tilbrook PA, Adenan AS, Chappell D, Ingley E, Sarna MK, Palmer TN, Watowich SS, Klinken SP. Dominant action of mutated erythropoietin receptors on differentiation in vitro and erythroleukemia development in vivo. Oncogene 2000; 19:953-60. [PMID: 10702804 DOI: 10.1038/sj.onc.1203370] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
J2E cells produce rapid, fatal erythroleukemias in vivo but still respond to erythropoietin (epo) in vitro by differentiating, proliferating and remaining viable in the absence of serum. Mutant epo receptors were introduced into these cells to determine whether they could influence the different biological responses to epo in vitro and the development of erythroleukemias. Three mutant receptors were used as cytoplasmic truncation mutants Delta257 and Delta321 (above box 1 and below box 2 respectively), and the cytoplasmic point mutant W282R (defective for JAK2 activation). Strikingly, the Delta321 mutation produced a hyper-sensitive response in vitro to epo-induced differentiation and viability, but not to proliferation. In contrast with the Delta321 receptor, the Delta257 and W282R mutants inhibited all biological responses to epo due to impaired JAK2 phosphorylation. Significantly, erythroleukemias took almost twice as long to develop with cells containing the W282R mutation, indicating that JAK2 plays an important role in the emergence of these leukemias. These data demonstrate that mutant epo receptors dominantly altered responses of J2E cells to epo in culture and the development of erythroleukemias. Oncogene (2000) 19, 953 - 960.
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MESH Headings
- Animals
- Cell Differentiation/genetics
- Cell Division/genetics
- Cell Survival/genetics
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Cell Transformation, Neoplastic/pathology
- Erythropoietin/metabolism
- Erythropoietin/physiology
- Genes, Dominant
- Janus Kinase 2
- Leukemia, Erythroblastic, Acute/etiology
- Leukemia, Erythroblastic, Acute/genetics
- Leukemia, Erythroblastic, Acute/metabolism
- Leukemia, Erythroblastic, Acute/pathology
- Mice
- Mutation/genetics
- Phosphorylation
- Protein-Tyrosine Kinases/metabolism
- Proto-Oncogene Proteins
- Receptors, Erythropoietin/genetics
- Receptors, Erythropoietin/metabolism
- Tumor Cells, Cultured
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Affiliation(s)
- V Cull
- Laboratory for Cancer Medicine, Department of Biochemistry, University of Western Australia and Royal Perth Hospital, Western Australia, Australia
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22
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Erythropoietin Receptor Mutations Associated With Familial Erythrocytosis Cause Hypersensitivity to Erythropoietin in the Heterozygous State. Blood 1999. [DOI: 10.1182/blood.v94.7.2530.419k35_2530_2532] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Inherited mutations in the erythropoietin receptor (EPOR) causing premature termination of the receptor cytoplasmic region are associated with dominant familial erythrocytosis (FE), a benign clinical condition characterized by hypersensitivity of erythroid progenitor cells to EPO and low serum EPO (S-EPO) levels. We describe a Swedish family with dominant FE in which erythrocytosis segregates with a new truncation in the negative control domain of the EPOR. We show that cells engineered to concomitantly express the wild-type (WT) EPOR and mutant EPORs associated with FE (FE EPORs) are hypersensitive to EPO-stimulated proliferation and activation of Jak2 and Stat5. These results demonstrate that FE is caused by hyperresponsiveness of receptor-mediated signaling pathways and that this is dominant with respect to WT EPOR signaling.
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23
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Abstract
The hormone erythropoietin (Epo) is essential for red blood cell development. Epo binds a high affinity receptor on the surface of erythroid progenitor cells, stimulating receptor dimerization and activation of the intracellular signal transduction pathways that support erythroid cell survival, proliferation and differentiation. Biochemical and structural analysis of the erythropoietin receptor (EpoR) is revealing the molecular mechanisms of EpoR function, leading the way to the development of small molecule Epo mimetics. This review focuses on the role EpoR dimerization plays in receptor function.
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Affiliation(s)
- S S Watowich
- Department of Immunology, University of Texas MD Anderson Cancer Center, Houston 77030, USA.
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24
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Grötzinger J, Kernebeck T, Kallen KJ, Rose-John S. IL-6 type cytokine receptor complexes: hexamer, tetramer or both? Biol Chem 1999; 380:803-13. [PMID: 10494829 DOI: 10.1515/bc.1999.100] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The typical protein fold of most cytokines is a bundle of four antiparallel helices. This 'four-helical bundle fold' seems to be unique to cytokines and has not been detected in other proteins. Cytokine receptors, however, can be classified as a subfamily of the immunoglobulin superfamily. Cytokines using the same receptor subunits are grouped into cytokine families. The interleukin-6 (IL-6) type cytokine family comprises six members. IL-6 type cytokines may interact with three receptor subunits instead of the usual two subunits. A tetramer would be the simplest model to describe such a receptor complex, but present orthodoxy describes the active complexes of IL-6 and ciliary neurotrophic factor (CNTF) as hexamers. Here, we summarize the structural and biochemical information on IL-6 type cytokines and discuss interactions between cytokine and individual receptor subunits at alternative positions. Contradictory results regarding the stoichiometry and assembly of signaling receptor complexes are rationalized by a new, unique model. The model stipulates that a ligand-induced transition from an active tetrameric to an inactive hexameric complex serves as a molecular switch that turns off cytokine signals in the presence of supraoptimal cytokine concentrations.
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Affiliation(s)
- J Grötzinger
- Institut für Biochemie, Universitätsklinikum RWTH Aachen, Germany
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