Apparatus and Growth Hormone Receptor Signaling
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Functional Interaction of Common γ-Chain and Growth Hormone Receptor Signaling Apparatus This information is current as Marsilio Adriani, Corrado Garbi, Giada Amodio, Ilaria of October 2, 2021. Russo, Marica Giovannini, Stefania Amorosi, Eliana Matrecano, Elena Cosentini, Fabio Candotti and Claudio Pignata J Immunol 2006; 177:6889-6895; ; doi: 10.4049/jimmunol.177.10.6889 http://www.jimmunol.org/content/177/10/6889 Downloaded from References This article cites 42 articles, 14 of which you can access for free at: http://www.jimmunol.org/content/177/10/6889.full#ref-list-1 http://www.jimmunol.org/ Why The JI? Submit online. • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication by guest on October 2, 2021 *average Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 2006 by The American Association of Immunologists All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. The Journal of Immunology Functional Interaction of Common ␥-Chain and Growth Hormone Receptor Signaling Apparatus1 Marsilio Adriani,* Corrado Garbi,† Giada Amodio,* Ilaria Russo,* Marica Giovannini,* Stefania Amorosi,* Eliana Matrecano,* Elena Cosentini,‡ Fabio Candotti,§ and Claudio Pignata2* We previously reported on an X-linked SCID (X-SCID) patient, who also had peripheral growth hormone (GH) hyporesponsive- ness and abnormalities of the protein phosphorylation events following GH receptor (GHR) stimulation. In the present study, we ␥ ␥ examined a potential role of common cytokine receptor -chain ( c) in GHR signaling using EBV-transformed lymphocytes from ␥ healthy subjects and c-negative X-SCID patients. We demonstrated that the proliferative response to GH stimulation of the B cell ␥ lines of c-negative patients was impaired despite a comparable cellular expression of GHR molecules to controls. In patients, after GH stimulation, no phosphorylation of STAT5 was observed. In addition, the molecule localization through confocal microscopy Downloaded from revealed that in B cell lines of patients no nuclear translocation of STAT5b following GH stimulation occurred differently from ␥ controls. Biochemical analysis of the nuclear extracts of c-negative cell lines provided further evidence that the amount of ␥ STAT5b and its phosphorylated form did not increase following GH stimulation. In patients, cells reconstituted with wild-type c abnormal biochemical and functional events were restored resulting in nuclear translocation of STAT5. Confocal experiments ␥ revealed that GHR and c were colocalized on the cell membrane. Our study demonstrates the existence of a previously unap- ␥ http://www.jimmunol.org/ preciated relationship between GHR-signaling pathway and c, which is required for the activation of STAT5b in B cell lines. These data also confirm that growth failure in X-SCID is primarily related to the genetic alteration of the IL2RG gene. The Journal of Immunology, 2006, 177: 6889–6895. evere combined immunodeficiencies represent a wide component of several receptors critical for the development and spectrum of illnesses, which differ in either the qualitative function of lymphocytes (3). To our knowledge, an extrahemopoi- or quantitative alterations of T, B, and NK cell (1). Most etic role of ␥ has not yet been demonstrated, although the abun- S c forms of SCID are associated with molecular alterations of genes dance of the protein in nonhemopoietic cells would imply addi- selectively expressed in hemopoietic cells and implicated in the tional functions for this element (4, 5). cell differentiation/activation process. Thus, classical symptoms We previously reported on a patient affected with X-SCID who by guest on October 2, 2021 are generally considered those related to the immunological im- received a bone marrow transplantation late at 5.2 years of age. In pairment that results in increased susceptibility to infections. Be- this patient, short stature became evident, and a peripheral growth cause patients usually die by the first year of age without an ef- hormone (GH) hyporesponsiveness associated with abnormalities fective treatment, the clinical phenotype is predominated by the of the protein phosphorylation events that occur following GH life-threatening problems. receptor (GHR) stimulation was demonstrated. X-linked SCID (X-SCID)3 is the most common form of the The GHR was the first identified member of the cytokine re- disease accounting for approximately half of all cases (2, 3). The ceptor class 1 superfamily, which includes receptors for erythro- gene responsible for X-SCID is IL2RG that encodes for the com- poietin, G-CSF, GM-CSF, IL-2–7, IL-9, IL-11, IL-12, and many ␥ ␥ mon cytokine receptor -chain ( c), a member of the cytokine other cytokines. Due to the lack of intrinsic kinase activity, mem- receptor class 1 superfamily. The molecule represents a shared bers of the cytokine receptor superfamily recruit and/or activate cytoplasmic tyrosine kinases to relay their cellular signal. The JAK2 represents the predominant nonreceptor tyrosine kinase re- *Department of Pediatrics, †Department of Cellular and Molecular Biology and Pa- quired for the initiation of GH signal transduction upon ligand ‡ thology, and Immunohematology Unit, “Federico II” University, Naples, Italy; and binding to the receptor (6, 7). However, GH also stimulates ty- §Genetics and Molecular Biology Branch, National Human Genome Research Insti- tute, National Institutes of Health, Bethesda, MD 20892 rosine phosphorylation of JAK1 (8, 9) and JAK3 (10) in certain Received for publication July 21, 2005. Accepted for publication August 16, 2006. cell lines. Signal transduction through GHR also involves a wide The costs of publication of this article were defrayed in part by the payment of page array of molecules, such as STATs 1, 3, and 5, ERK 1 and 2, and charges. This article must therefore be hereby marked advertisement in accordance PI3K-protein kinase B (7). Activation of STAT5b is considered a with 18 U.S.C. Section 1734 solely to indicate this fact. prominent event in GH signaling and is crucial for the regulation 1 This work was supported by Ministero della Salute-Roma and Regione Campania, of transcription of GH-responsive genes, including the gene en- Legge 502 and Ministero dell’Universita`e della Ricerca Scı`entifica e Tecnologica, Progetto di Rilevante Interesse Nazionale and by the Division of Intramural Research, coding for insulin-like growth factor (IGF)-I, which mediates National Human Genome Research Institute, National Institutes of Health. many of the GH biological functions (11–13). In our previous 2 Address correspondence and reprint request to Dr. Claudio Pignata, Department of study, mutational screening and expressional analysis failed to re- Pediatrics, Unit of Immunology, “Federico II” University, Via S. Pansini 5-80131, veal any molecular alteration of GHR, JAK2, and STAT5A/B genes in Naples, Italy. E-mail address: [email protected] the patient with X-SCID and peripheral GH hyporesponsiveness (14). 3 ␥ Abbreviations used in this paper: X-SCID, X-linked SCID; c, common cytokine ␥ receptor ␥-chain; GH, growth hormone; GHR, GH receptor; IGF, insulin-like growth Because we hypothesized a role for the c in GHR signaling, in factor; rGH, recombinant human GH; BCL, lymphoblastoid cell line; WT, wild type. this study, we evaluate the functional interaction between GHR Copyright © 2006 by The American Association of Immunologists, Inc. 0022-1767/06/$02.00 ␥ 6890 FUNCTIONAL INTERACTION BETWEEN c AND GHR and the common ␥ element in either freshly isolated or EBV-trans- Western blot formed lymphocytes from X-SCID patients and healthy subjects. Immunoblotting using phosphotyrosine mAb was performed as previously In particular, the functional response to GH stimulation, the pattern reported (14). Immunoblotting using specific Ab was performed according of GHR-induced protein tyrosine phosphorylation and GH-in- to the vendor protocols. In brief, protein samples separated by SDS-PAGE duced translocation from the cytoplasm to the nucleus of STAT5 were transferred onto Mixed Cellulose Esters membranes (Immobilon-NC were evaluated. We demonstrate the existence of a previously un- Mixed Cellulose Esters 0.45 m; Millipore). The membrane was incubated ␥ at room temperature for1hinblocking buffer consisting of 10% BSA in appreciated functional interaction between c and GHR. This in- wash buffer (10 mM Tris (pH 7.5), 100 mM NaCl, and 0.1% Tween 20). teraction leads to the activation and intranuclear translocation of The membrane was then washed three times in wash buffer and incubated the STAT5b protein. 1 h at room temperature or overnight at 4°C with the specific Ab. The membrane was then washed three times and an appropriate IgG HRP- conjugated secondary Ab was used for the second incubation. After further Materials and Methods washings, the membrane was developed with ECL-developing reagents, Reagents and exposed to x-ray films according to the manufacturer’s instructions (Amersham