Sample records for adipokinetic hormone receptor

  1. Molecular identification of the insect adipokinetic hormone receptors

    Staubli, Frank; Jørgensen, Thomas J. D.; Cazzamali, Giuseppe;


    The insect adipokinetic hormones (AKHs) are a large family of peptide hormones that are involved in the mobilization of sugar and lipids from the insect fat body during energy-requiring activities such as flight and locomotion, but that also contribute to hemolymph sugar homeostasis. Here, we have...... identified the first insect AKH receptors, namely those from the fruitfly Drosophila melanogaster and the silkworm Bombyx mori. These results represent a breakthrough for insect molecular endocrinology, because it will lead to the cloning of all AKH receptors from all model insects used in AKH research, and......, therefore, to a better understanding of AKH heterogeneity and actions. Interestingly, the insect AKH receptors are structurally and evolutionarily related to the gonadotropin-releasing hormone receptors from vertebrates....

  2. Characterization of the adipokinetic hormone receptor of the anautogenous flesh fly, Sarcophaga crassipalpis.

    Bil, Magdalena; Timmermans, Iris; Verlinden, Heleen; Huybrechts, Roger


    Adipokinetic hormone (AKH) is an insect neuropeptide mainly involved in fat body energy mobilization. In flies (Phormia regina, Sarcophaga crassipalpis), bugs (Pyrrhocoris apterus) and cockroaches (Periplaneta americana) AKH was also demonstrated to be involved in the regulation of digestion. This makes AKH an important peptide for anautogenous female flies that need to feed on a supplementary protein meal to initiate vitellogenesis, the large scale synthesis of yolk proteins and their uptake by the developing oocytes. Flesh fly AKH, originally identified as Phormia terraenovae hypertrehalosemic hormone (PhoteHrTH), functions through activation of the AKH receptor (AKHR). This is a G protein-coupled receptor that is the orthologue of the human gonadotropin-releasing hormone receptor. Pharmacological characterization indicated that the receptor can be activated by two related dipteran AKH ligands with an EC50 value in the low nanomolar range, whereas micromolar concentrations of the Tribolium castaneum AKH were needed. Consistent with the energy mobilizing function of AKH, the receptor transcript levels were most abundant in the fat body tissue. Nonetheless, Sarcophaga crassipalpis AKHR transcript levels were also high in the brain, the foregut and the hindgut. Interestingly, the receptor transcript numbers were reduced in almost all measured tissues after protein feeding. These changes may enforce the use of ingested energy carrying molecules prior to stored energy mobilization. PMID:27063262

  3. Characterization and expression analysis of adipokinetic hormone and its receptor in eusocial aphid Pseudoregma bambucicola.

    Jedličková, Veronika; Jedlička, Pavel; Lee, How-Jing


    Aphids display an extraordinary phenotypic plasticity ranging from widespread reproductive and wing polyphenisms to the occurrence of sterile or subfertile soldier morphs restricted to eusocial species of the subfamilies Eriosomatinae and Hormaphidinae. Individual morphs are specialized by their behavior, anatomy, and physiology to perform different roles in aphid societies at different stages of the life cycle. The capacity of the insects to cope with environmental stressors is under the control of a group of neuropeptides of the adipokinetic hormone/red pigment-concentrating hormone family (AKH/RPCH) that bind to a specific receptor (AKHR). Here, we describe the molecular characteristics of AKH and AKHR in the eusocial aphid Pseudoregma bambucicola. The sequence of the bioactive AKH decapeptide and the intron position in P. bambucicola AKH preprohormone were found to be identical to those in a phylogenetically distant aphid Dreyfusia spp. (Adelgidae). We detected four transcript variants of AKHR that are translated into three protein isoforms. Further, we analyzed AKH/AKHR expression in different tissues and insects of different castes. In wingless females, a remarkable amount of AKH mRNA was only expressed in the heads. In contrast, AKHR transcript levels increased in the order gut

  4. Enhancement of insecticide efficacy by adipokinetic hormones

    Kodrík, Dalibor; Plavšin, Ivana; Velki, Mirna; Stašková, Tereza

    New York: NovaScience Publishers,Inc, 2015 - (Montgomery, J.), s. 77-91 ISBN 978-1-63483-475-9 R&D Projects: GA ČR GA14-07172S Institutional support: RVO:60077344 Keywords : adipokinetic hormones Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection

  5. Insect lipids mobilized by adipokinetic hormones

    Kodrík, Dalibor; Tomčala, Aleš; Bártů, Iva; Socha, Radomír

    New York: Nova Science Publishers, Inc, 2012 - (Langella, J.), s. 99-122 ISBN 978-1-61209-566-0 R&D Projects: GA ČR GAP501/10/1215; GA ČR GAP502/10/1734 Institutional research plan: CEZ:AV0Z50070508; CEZ:AV0Z40550506 Keywords : adipokinetic hormones Subject RIV: ED - Physiology

  6. Adipokinetic hormone receptor gene identification and its role in triacylglycerol metabolism in the blood-sucking insect Rhodnius prolixus.

    Alves-Bezerra, Michele; De Paula, Iron F; Medina, Jorge M; Silva-Oliveira, Gleidson; Medeiros, Jonas S; Gäde, Gerd; Gondim, Katia C


    Adipokinetic hormone (AKH) has been associated with the control of energy metabolism in a large number of arthropod species due to its role on the stimulation of lipid, carbohydrate and amino acid mobilization/release. In the insect Rhodnius prolixus, a vector of Chagas' disease, triacylglycerol (TAG) stores must be mobilized to sustain the metabolic requirements during moments of exercise or starvation. Besides the recent identification of the R. prolixus AKH peptide, other components required for the AKH signaling cascade and its mode of action remain uncharacterized in this insect. In the present study, we identified and investigated the expression profile of the gene encoding the AKH receptor of R. prolixus (RhoprAkhr). This gene is highly conserved in comparison to other sequences already described and its transcript is abundant in the fat body and the flight muscle of the kissing bug. Moreover, RhoprAkhr expression is induced in the fat body at moments of increased TAG mobilization; the knockdown of this gene resulted in TAG accumulation both in fat body and flight muscle after starvation. The inhibition of Rhopr-AKHR transcription as well as the treatment of insects with the peptide Rhopr-AKH in its synthetic form altered the transcript levels of two genes involved in lipid metabolism, the acyl-CoA-binding protein-1 (RhoprAcbp1) and the mitochondrial glycerol-3-phosphate acyltransferase-1 (RhoprGpat1). These results indicate that the AKH receptor is regulated at transcriptional level and is required for TAG mobilization under starvation. In addition to the classical view of AKH as a direct regulator of enzymatic activity, we propose here that AKH signaling may account for the regulation of nutrient metabolism by affecting the expression profile of target genes. PMID:26163435

  7. Cloning and characterization of the adipokinetic hormone receptor from the cockroach Periplaneta americana

    Hansen, Karina K; Hauser, Frank; Cazzamali, Giuseppe;


    americana. This receptor is only activated by various insect AKHs (we tested eight) and not by a library of 29 other insect or invertebrate neuropeptides and nine biogenic amines. Periplaneta has two intrinsic AKHs, Pea-AKH-1, and Pea-AKH-2. The Periplaneta AKH receptor is activated by low concentrations of...

  8. Identification, characterisation, and function of adipokinetic hormones and receptor in the African malaria mosquito, "Anopheles Gambiae" (Diptera)

    Kaufmann, Christian; Betschart, Bruno


    En utilisant la bioinformatique et la biologie moléculaire, nous avons pu identifier chez le principal vecteur africain de la malaria, le moustique, Anopheles gambiae deux hormones adipokinétiques (AKHs): l'octapeptide, Anoga-AKH-I (pQLTFTPAWa) et le décapeptide, Anoga-AKH-II, (pQVTFSRDWNAa). La fonction principale des AKHs est d’induire une hyperlipémie (effet d’adipokinétique), ainsi qu’une hypertrehalosémie et une hyperprolinémie. En tant que membres de la famille des AKH, les deux neurope...

  9. Lipid mobilization and locomotor stimulation in Gryllus bimaculatus by topically applied adipokinetic hormone

    Lorenz, M. W.; Zemek, Rostislav; Kodrík, Dalibor; Socha, Radomír


    Roč. 29, - (2004), s. 146-151. ISSN 0307-6962 R&D Projects: GA AV ČR IAA6007202 Institutional research plan: CEZ:AV0Z5007907 Keywords : Adipokinetic hormone * cricket * Grybi-AKH Subject RIV: ED - Physiology Impact factor: 1.352, year: 2004

  10. Functional characterization of the adipokinetic hormone in the pea aphid, Acyrthosiphon pisum

    Jedlička, Pavel; Steinbauerová, V.; Šimek, Petr; Zahradníčková, Helena


    Roč. 162, č. 1 (2012), s. 51-58. ISSN 1095-6433 R&D Projects: GA ČR GP522/09/P382 Grant ostatní: European Union FP7(CZ) MOBITAG, GA 229518 Institutional research plan: CEZ:AV0Z50070508 Keywords : adipokinetic hormone * Acyrthosiphon pisum * neuropeptide Subject RIV: ED - Physiology Impact factor: 2.167, year: 2012

  11. Gonadotropin-releasing hormone and Adipokinetic hormone signaling systems share a common evolutionary origin

    Marleen eLindemans


    Full Text Available Gonadotropin-releasing hormone (GnRH is a critical and central hormone that regulates vertebrate reproduction. The high conservation of GnRH signaling within the chordates (deuterostomians raises the important question as to whether its appearance might date back prior to the divergence of protostomian and deuterostomian lineages, about 700 million years ago. This leads to several important questions regarding the evolution of the GnRH family. Has GnRH been retained in most protostomian lineages? And was regulation of reproduction already a function of ancestral GnRH? The first question can undoubtedly be answered affirmatively since several GnRH-like sequences have been found in wide variety of protostomian and deuterostomian phyla. However, based on their different primary functions in different phyla – which implies a less unanimous answer on the second question – consistency in the nomenclature of this peptide family has been lost. A comparative and phylogenetic approach shows that the ecdysozoan adipokinetic hormones (AKHs, lophotrozoan GnRHs and chordate GnRHs are structurally related and that they all originate from a common ancestor. This review supports the view that the AKH-GnRH signaling system probably arose very early in metazoan evolution, prior to the divergence of protostomians and deuterostomians.

  12. Adipokinetic hormones (AKHs) of sphingid Lepidoptera, including the identification of a second M. sexta AKH.

    Weaver, Robert J; Marco, Heather G; Simek, Petr; Audsley, Neil; Clark, Kevin D; Gäde, Gerd


    The adipokinetic hormones (AKHs) from the corpora cardiaca (CC) of representative species from all three subfamilies of the Sphingidae (hawkmoths) were investigated using matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) and liquid chromatography electrospray ion trap mass spectrometry (LC-ESI MS), including a re-examination of the AKH complement of the tobacco hawkmoth, Manduca sexta. In addition to larvae and adults of M. sexta (subfamily: Sphinginae), adults from the following subfamilies were examined: Macroglossinae (large elephant hawkmoth, Deilephila elpenor), Smerinthinae (poplar hawkmoth, Laothoe populi and eyed hawkmoth, Smerinthus ocellata), and Sphinginae (death's head hawkmoth, Acherontia atropos). All moths are shown to have the nonapeptide Manse-AKH (pELTFTSSWGamide) [corrected] in their CC, together with a second AKH, which, on the basis of mass ions ([M+Na](+), [M+K](+)) and partial sequence analysis is identical in all species examined. The structure of this AKH was extracted from the CC [corrected] of adult M. sexta and shown, by ESI-collision-induced dissociation (CID) tandem mass spectrometry (MS/MS), to be a novel decapeptide AKH with a sequence of pELTFSSWGQamide. [corrected]. The new peptide has been code named Manse-AKH-II. Sequence confirmation was obtained from identical MS studies with synthetic Manse-AKH-II and with the native peptide. Manse-AKH-II has significant lipid-mobilizing activity when injected at low dose (5pmol) into newly emerged adult M. sexta. The potential implications of a second AKH, in M. sexta in particular, are discussed in relation to putative receptor(s). PMID:22285789

  13. Adipokinetic hormones (AKHs) of sphingid Lepidoptera, including the identification of a second M. sexta AKH

    Weaver, R. J.; Marco, H. G.; Šimek, Petr; Audsley, N.; Clark, K. D.; Gäde, G.


    Roč. 34, č. 1 (2012), s. 44-50. ISSN 0196-9781 R&D Projects: GA ČR GAP206/10/2401 Grant ostatní: NRF - Royal Society UK(GB) NRF GUN 63515; National Research Foundation(ZA) FA2007021300002; National Research Foundation(ZA) IFR2008071500048 Institutional research plan: CEZ:AV0Z50070508 Keywords : Insect * Sphingidae * adipokinetic hormone Subject RIV: ED - Physiology Impact factor: 2.522, year: 2012

  14. Stimulatory effects of bioamines norepinephrine and dopamine on locomotion of Pyrrhocoris apterus (L.): Is the adipokinetic hormone involved?

    Socha, Radomír; Kodrík, Dalibor; Zemek, Rostislav


    Roč. 151, č. 3 (2008), s. 305-310. ISSN 1096-4959 R&D Projects: GA ČR GA522/07/0788 Institutional research plan: CEZ:AV0Z50070508 Keywords : adipokinetic hormone * biogenic amine * CNS Subject RIV: ED - Physiology Impact factor: 1.468, year: 2008

  15. Adipokinetic hormone (Pyrap-AKH) enhances the effect of a pyrethroid insecticide against the firebug Pyrrhocoris apterus

    Kodrík, Dalibor; Bártů, Iva; Socha, Radomír


    Roč. 66, č. 4 (2010), s. 425-431. ISSN 1526-498X R&D Projects: GA ČR GA522/07/0788 Institutional research plan: CEZ:AV0Z50070508 Keywords : insecticide * adipokinetic hormone * stress Subject RIV: ED - Physiology Impact factor: 2.313, year: 2010

  16. Adipokinetic hormone-induced enhancement of antioxidant capacity of Pyrrhocoris apterus hemolymph in response to oxidative stress

    Večeřa, J.; Krishnan, Natraj; Alquicer, Glenda; Kodrík, Dalibor; Socha, Radomír


    Roč. 146, - (2007), s. 336-342. ISSN 1532-0456 R&D Projects: GA ČR GA522/07/0788 Institutional research plan: CEZ:AV0Z50070508 Keywords : adipokinetic hormone * antioxidant activity * oxidative stress Subject RIV: ED - Physiology Impact factor: 2.345, year: 2007

  17. Preparation of a specifically tritiated locust adipokinetic hormone analog with full biological potency

    A synthetic peptide related to locus adipokinetic hormone (AKH) and shrimp red pigment concentrating hormone (RPCH) containing a tyrosine residue in place of phenylalanine was iodinated and the 3,5-diiodotyrosyl derivative was isolated by reverse phase HPLC. Catalytic dehalogenation of the diiodo derivative in the presence of tritium yielded the tritiated AKH analog which was isolated by gel filtration on Sephadex LH-20 and reverse phase HPLC. The tritiated peptide was formed to be identical to AKH in its ability to stimulate lipid release into the hemolymph of locusts in vivo where the diiodotryrosyl derivative was inactive. The specific radioactivity of the tritiated peptide was 57.2 Ci/mmol, or 99% of the theoretical value. (author)

  18. Role of adipokinetic hormone and adenosine in the anti-stress response in Drosophila melanogaster.

    Zemanová, Milada; Stašková, Tereza; Kodrík, Dalibor


    The role of adipokinetic hormone (AKH) and adenosine in the anti-stress response was studied in Drosophila melanogaster larvae and adults carrying a mutation in the Akh gene (Akh(1)), the adenosine receptor gene (AdoR(1)), or in both of these genes (Akh(1) AdoR(1) double mutant). Stress was induced by starvation or by the addition of an oxidative stressor paraquat (PQ) to food. Mortality tests revealed that the Akh(1) mutant was the most resistant to starvation, while the AdoR(1) mutant was the most sensitive. Conversely, the Akh(1) AdoR(1) double mutant was more sensitive to PQ toxicity than either of the single mutants. Administration of PQ significantly increased the Drome-AKH level in w(1118) and AdoR(1) larvae; however, this was not accompanied by a simultaneous increase in Akh gene expression. In contrast, PQ significantly increased the expression of the glutathione S-transferase D1 (GstD1) gene. The presence of both a functional adenosine receptor and AKH seem to be important for the proper control of GstD1 gene expression under oxidative stress, however, the latter appears to play more dominant role. On the other hand, differences in glutathione S-transferase (GST) activity among the strains, and between untreated and PQ-treated groups were minimal. In addition, the glutathione level was significantly lower in all untreated AKH- or AdoR-deficient mutant flies as compared with the untreated control w(1118) flies and further declined following treatment with PQ. All oxidative stress characteristics modified by mutations in Akh gene were restored or even improved by 'rescue' mutation in flies which ectopically express Akh. Thus, the results of the present study demonstrate the important roles of AKH and adenosine in the anti-stress response elicited by PQ in a D. melanogaster model, and provide the first evidence for the involvement of adenosine in the anti-oxidative stress response in insects. PMID:27374982

  19. Knockdown of adipokinetic hormone synthesis increases susceptibility to oxidative stress in Drosophila – A role for dFoxO?

    Bednářová, Andrea; Kodrík, Dalibor; Krishnan, N.


    Roč. 171, May 01 (2015), s. 8-14. ISSN 1532-0456 R&D Projects: GA ČR GA14-07172S; GA MŠk(CZ) LH14047 Grant ostatní: GA JU(CZ) 140/2014/P Institutional support: RVO:60077344 Keywords : adipokinetic hormone * Drosophila * hydrogen peroxide Subject RIV: ED - Physiology Impact factor: 2.301, year: 2014

  20. The Putative AKH Receptor of the Tobacco Hornworm, Manduca sexta, and Its Expression

    Ziegler, R.; Isoe, J.; Moore, W.; Riehle, M. A.; Wells, M. A.


    Adipokinetic hormones are peptide hormones that mobilize lipids and/or carbohydrates for flight in adult insects and activate glycogen Phosphorylase in larvae during starvation and during molt. We previously examined the functional roles of adipokinetic hormone in Manduca sexta L. (Lepidoptera: Sphingidae). Here we report the cloning of the full-length cDNA encoding the putative adipokinetic hormone receptor from the fat body of M. sexta. The sequence analysis shows that the deduced amino aci...

  1. Unique roles od glucagon and glucagon-like peptides: Parallels in understanding the functions of adipokinetic hormones in stress responses in insects

    Bednářová, Andrea; Kodrík, Dalibor; Krishnan, N.


    Roč. 164, č. 1 (2013), s. 91-100. ISSN 1095-6433 R&D Projects: GA ČR GAP501/10/1215 Grant ostatní: National Science Foundation, EPSCOR(US) MSU 012156-014 Institutional support: RVO:60077344 Keywords : adipokinetic hormone * glucagon * glucagon-like peptide Subject RIV: ED - Physiology Impact factor: 2.371, year: 2013

  2. Discovery of a novel insect neuropeptide signaling system closely related to the insect adipokinetic hormone and corazonin hormonal systems

    Hansen, Karina Kiilerich; Stafflinger, Elisabeth; Schneider, Martina;


    structurally related to the AKHs but represent a different neuropeptide signaling system. We have previously cloned an orphan GPCR from the malaria mosquito Anopheles gambiae that was structurally intermediate between the A. gambiae AKH and corazonin GPCRs. Using functional expression of the receptor in cells...... in cell culture, we have now identified the ligand for this orphan receptor as being pQVTFSRDWNAamide, a neuropeptide that is structurally intermediate between AKH and corazonin and that we therefore named ACP (AKH/corazonin-related peptide). ACP does not activate the A. gambiae AKH and corazonin...

  3. Adipokinetic hormone exerts its anti-oxidative effects using a conserved signal-transduction mechanism involving both PKC and cAMP by mobilizing extra- and intracellular Ca2+ stores

    Bednářová, Andrea; Kodrík, Dalibor; Krishnan, N.


    Roč. 158, č. 3 (2013), s. 142-149. ISSN 1532-0456 R&D Projects: GA ČR GAP501/10/1215 Grant ostatní: Mississippi State Univeristy(US) 062/2011/P; NSF, EPSCOR(US) MSU No. 269110-151250 Institutional support: RVO:60077344 Keywords : adipokinetic hormone * calcium channel * cell signaling Subject RIV: ED - Physiology Impact factor: 2.829, year: 2013

  4. The putative AKH receptor of the tobacco hornworm, Manduca sexta, and its expression.

    Ziegler, R; Isoe, J; Moore, W; Riehle, M A; Wells, M A


    Adipokinetic hormones are peptide hormones that mobilize lipids and/or carbohydrates for flight in adult insects and activate glycogen Phosphorylase in larvae during starvation and during molt. We previously examined the functional roles of adipokinetic hormone in Manduca sexta L. (Lepidoptera: Sphingidae). Here we report the cloning of the full-length cDNA encoding the putative adipokinetic hormone receptor from the fat body of M. sexta. The sequence analysis shows that the deduced amino acid sequence shares common motifs of G protein-coupled receptors, by having seven hydrophobic transmembrane segments. We examined the mRNA expression pattern of the adipokinetic hormone receptor by quantitative Real-Time PCR in fat body during development and in different tissues and found the strongest expression in fat body of larvae two days after molt to the fifth instar. We discuss these results in relation to some of our earlier results. We also compare the M. sexta adipokinetic hormone receptor with the known adipokinetic hormone receptors of other insects and with gonadotropin releasing hormone-like receptors of invertebrates. PMID:21529255

  5. Molecular characterization, tissue distribution, and ultrastructural localization of adipokinetic hormones in the CNS of the firebug Pyrrhocoris apterus (Heteroptera, Insecta)

    Kodrík, Dalibor; Stašková, Tereza; Jedličková, V.; Weyda, F.; Závodská, Radka; Pflegerová, Jitka


    Roč. 210, Jan 1 (2015), s. 1-11. ISSN 0016-6480 R&D Projects: GA ČR GA14-07172S Institutional support: RVO:60077344 Keywords : AKH * pre-pro-hormone * insect brain Subject RIV: ED - Physiology Impact factor: 2.470, year: 2014

  6. Plant hormone receptors: new perceptions

    Spartz, Angela K.; William M Gray


    Plant growth and development require the integration of a variety of environmental and endogenous signals that, together with the intrinsic genetic program, determine plant form. Central to this process are several growth regulators known as plant hormones or phytohormones. Despite decades of study, only recently have receptors for several of these hormones been identified, revealing novel mechanisms for perceiving chemical signals and providing plant biologists with a much clearer picture of...

  7. Trans-activation by thyroid hormone receptors: functional parallels with steroid hormone receptors.

    Thompson, C C; Evans, R M


    The effects of thyroid hormones are mediated through nuclear receptor proteins that modulate the transcription of specific genes in target cells. We previously isolated cDNAs encoding two different mammalian thyroid hormone receptors, one from human placenta (hTR beta) and the other from rat brain (rTR alpha), and showed that their in vitro translation products bind thyroid hormones with the characteritistic affinities of the native thyroid hormone receptor. We now demonstrate that both of th...

  8. Rapid steroid hormone actions via membrane receptors.

    Schwartz, Nofrat; Verma, Anjali; Bivens, Caroline B; Schwartz, Zvi; Boyan, Barbara D


    Steroid hormones regulate a wide variety of physiological and developmental functions. Traditional steroid hormone signaling acts through nuclear and cytosolic receptors, altering gene transcription and subsequently regulating cellular activity. This is particularly important in hormonally-responsive cancers, where therapies that target classical steroid hormone receptors have become clinical staples in the treatment and management of disease. Much progress has been made in the last decade in detecting novel receptors and elucidating their mechanisms, particularly their rapid signaling effects and subsequent impact on tumorigenesis. Many of these receptors are membrane-bound and lack DNA-binding sites, functionally separating them from their classical cytosolic receptor counterparts. Membrane-bound receptors have been implicated in a number of pathways that disrupt the cell cycle and impact tumorigenesis. Among these are pathways that involve phospholipase D, phospholipase C, and phosphoinositide-3 kinase. The crosstalk between these pathways has been shown to affect apoptosis and proliferation in cardiac cells, osteoblasts, and chondrocytes as well as cancer cells. This review focuses on rapid signaling by 17β-estradiol and 1α,25-dihydroxy vitamin D3 to examine the integrated actions of classical and rapid steroid signaling pathways both in contrast to each other and in concert with other rapid signaling pathways. This new approach lends insight into rapid signaling by steroid hormones and its potential for use in targeted drug therapies that maximize the benefits of traditional steroid hormone-directed therapies while mitigating their less desirable effects. PMID:27288742

  9. Hormone activation of baculovirus expressed progesterone receptors.

    Elliston, J F; Beekman, J M; Tsai, S Y; O'Malley, B W; Tsai, M J


    Human and chicken progesterone receptors (A form) were overproduced in a baculovirus expression system. These recombinant progesterone receptors were full-length bound progesterone specifically and were recognized by monoclonal antibodies, AB52 and PR22, specific for human and chicken progesterone receptor, respectively. In gel retardation studies, binding of recombinant human and chicken progesterone receptors to their progesterone response element (PRE) was specific and was enhanced in the presence of progesterone. Binding of human progesterone receptor to the PRE was also enhanced in the presence of the antiprogestin, RU486, but very little effect was observed in the presence of estradiol, dexamethasone, testosterone, and vitamin D. In our cell-free transcription system, human progesterone receptor induced transcription in a receptor-dependent and hormone-activable manner. Receptor-stimulated transcription required the presence of the PRE in the test template and could be specifically inhibited by excess PRE oligonucleotides. Furthermore, chicken progesterone receptor also induced in vitro transcription in a hormone-activable manner. These results demonstrate that steroid receptors overexpressed in a baculovirus expression system are functional and exhibit steroid-responsive binding and transcription. These observations support our present understanding of the mechanism of steroid receptor-regulated gene expression and provide a technological format for studies of the role of hormone and antihormone in altering gene expression. PMID:1544902

  10. NUREBASE: database of nuclear hormone receptors

    Duarte, Jorge; Perrière, Guy; Laudet, Vincent; Robinson-Rechavi, Marc


    Nuclear hormone receptors are an abundant class of ligand activated transcriptional regulators, found in varying numbers in all animals. Based on our experience of managing the official nomenclature of nuclear receptors, we have developed NUREBASE, a database containing protein and DNA sequences, reviewed protein alignments and phylogenies, taxonomy and annotations for all nuclear receptors. The reviewed NUREBASE is completed by NUREBASE_DAILY, automatically updated every 24 h. Both databases...

  11. Thyroid hormone receptor expression in cardiovascular disease and pharmacology

    Shahrara, Shiva


    The heart is a major target organ for thyroid hormone actions. Thyroid hormone exerts effects on the myocardium, which are mediated by specific nuclear receptors. The thyroid hormone receptors (TR) are members of the steroid hormone receptor superfamily. These receptors regulate gene expression by binding to the promotor region of target genes as monomers, homodimers or heterodimers depending on the thyroid hormone response element (TRE) and the presence or absence of th...

  12. Dimerization of the thyrotropin-releasing hormone receptor potentiates hormone-dependent receptor phosphorylation

    Song, Gyun Jee; Jones, Brian W.; Hinkle, Patricia M.


    The G protein-coupled thyrotropin (TSH)-releasing hormone (TRH) receptor forms homodimers. Regulated receptor dimerization increases TRH-induced receptor endocytosis. These studies test whether dimerization increases receptor phosphorylation, which could potentiate internalization. Phosphorylation at residues 355–365, which is critical for internalization, was measured with a highly selective phospho-site-specific antibody. Two strategies were used to drive receptor dimerization. Dimerization...

  13. Thyroid hormone receptors bind to defined regions of the growth hormone and placental lactogen genes.

    Barlow, J W; Voz, M L; Eliard, P H; Mathy-Harter, M; De Nayer, Philippe; Economidis, I V; Belayew, A; Martial, J A; Rousseau, Guy


    The intracellular receptor for thyroid hormone is a protein found in chromatin. Since thyroid hormone stimulates transcription of the growth hormone gene through an unknown mechanism, the hypothesis that the thyroid hormone-receptor complex interacts with defined regions of this gene has been investigated in a cell-free system. Nuclear extracts from human lymphoblastoid IM-9 cells containing thyroid hormone receptors were incubated with L-3,5,3'-tri[125I]iodothyronine and calf thymus DNA-cell...

  14. Genetic features of thyroid hormone receptors

    Maha Rebaï; Imen Kallel; Ahmed Rebaï


    Thyroid hormone receptors (TR) are prototypes of nuclear transcription factors that regulate the expression of target genes. These receptors play an important role in many physiological processes. Moreover, a dysfunction of these proteins is often implicated in several human diseases and malignancies. Here we report genetic variations and alterations of the TRs that have been described in the literature as well as their potential role in the development of some human diseases including cancers. The functional effects of some mutations and polymorphisms in TRs on disease susceptibility, especially on cancer risk, are now established. Therefore, further investigations are needed in order to use these receptors as therapeutic targets or as biological markers to decide on appropriate forms of treatment.

  15. Identification of a gonadotropin-releasing hormone receptor orthologue in Caenorhabditis elegans

    Sgro Jean-Yves


    Full Text Available Abstract Background The Caenorhabditis elegans genome is known to code for at least 1149 G protein-coupled receptors (GPCRs, but the GPCR(s critical to the regulation of reproduction in this nematode are not yet known. This study examined whether GPCRs orthologous to human gonadotropin-releasing hormone receptor (GnRHR exist in C. elegans. Results Our sequence analyses indicated the presence of two proteins in C. elegans, one of 401 amino acids [GenBank: NP_491453; WormBase: F54D7.3] and another of 379 amino acids [GenBank: NP_506566; WormBase: C15H11.2] with 46.9% and 44.7% nucleotide similarity to human GnRHR1 and GnRHR2, respectively. Like human GnRHR1, structural analysis of the C. elegans GnRHR1 orthologue (Ce-GnRHR predicted a rhodopsin family member with 7 transmembrane domains, G protein coupling sites and phosphorylation sites for protein kinase C. Of the functionally important amino acids in human GnRHR1, 56% were conserved in the C. elegans orthologue. Ce-GnRHR was actively transcribed in adult worms and immunoanalyses using antibodies generated against both human and C. elegans GnRHR indicated the presence of a 46-kDa protein, the calculated molecular mass of the immature Ce-GnRHR. Ce-GnRHR staining was specifically localized to the germline, intestine and pharynx. In the germline and intestine, Ce-GnRHR was localized specifically to nuclei as revealed by colocalization with a DNA nuclear stain. However in the pharynx, Ce-GnRHR was localized to the myofilament lattice of the pharyngeal musculature, suggesting a functional role for Ce-GnRHR signaling in the coupling of food intake with reproduction. Phylogenetic analyses support an early evolutionary origin of GnRH-like receptors, as evidenced by the hypothesized grouping of Ce-GnRHR, vertebrate GnRHRs, a molluscan GnRHR, and the adipokinetic hormone receptors (AKHRs and corazonin receptors of arthropods. Conclusion This is the first report of a GnRHR orthologue in C. elegans, which

  16. Evolution of the AKH/corazonin/ACP/GnRH receptor superfamily and their ligands in the Protostomia

    Hauser, Frank; Grimmelikhuijzen, Cornelis


    In this review we trace the evolutionary connections between GnRH receptors from vertebrates and the receptors for adipokinetic hormone (AKH), AKH/corazonin-related peptide (ACP), and corazonin from arthropods. We conclude that these G protein-coupled receptors (GPCRs) are closely related and hav......QLTFSSDWSGamide), and the penis worm Priapulus caudatus (pQIFFSKGWRGamide). This is the first report, showing that AKH signaling is widespread in molluscs....

  17. Dimerization of the thyrotropin-releasing hormone receptor potentiates hormone-dependent receptor phosphorylation.

    Song, Gyun Jee; Jones, Brian W; Hinkle, Patricia M


    The G protein-coupled thyrotropin (TSH)-releasing hormone (TRH) receptor forms homodimers. Regulated receptor dimerization increases TRH-induced receptor endocytosis. These studies test whether dimerization increases receptor phosphorylation, which could potentiate internalization. Phosphorylation at residues 355-365, which is critical for internalization, was measured with a highly selective phospho-site-specific antibody. Two strategies were used to drive receptor dimerization. Dimerization of a TRH receptor-FK506-binding protein (FKBP) fusion protein was stimulated by a dimeric FKBP ligand. The chemical dimerizer caused a large increase in TRH-dependent phosphorylation within 1 min, whereas a monomeric FKBP ligand had no effect. The dimerizer did not alter phoshorylation of receptors lacking the FKBP domain. Dimerization of receptors containing an N-terminal HA epitope also was induced with anti-HA antibody. Anti-HA IgG strongly increased TRH-induced phosphorylation, whereas monomeric Fab fragments had no effect. Anti-HA antibody did not alter phosphorylation in receptors lacking an HA tag. Furthermore, two phosphorylation-defective TRH receptors functionally complemented one another and permitted phosphorylation. Receptors with a D71A mutation in the second transmembrane domain do not signal, whereas receptors with four Ala mutations in the 355-365 region signal normally but lack phosphorylation sites. When D71A- and 4Ala-TRH receptors were expressed alone, neither underwent TRH-dependent phosphorylation. When they were expressed together, D71A receptor was phosphorylated by G protein-coupled receptor kinases in response to TRH. These results suggest that the TRH receptor is phosphorylated preferentially when it is in dimers or when preexisting receptor dimers are driven into microaggregates. Increased receptor phosphorylation may amplify desensitization. PMID:17989235

  18. Is the titer of adipokinetic peptides in Leptinotarsa decemlineata fed on genetically modified potatoes increased by oxidative stress?

    Kodrík, Dalibor; Krishnan, Natraj; Habuštová, Oxana


    Roč. 28, č. 5, (2007), s. 974-980. ISSN 0196-9781 R&D Projects: GA ČR GA522/05/0151; GA ČR(CZ) GA522/06/1591 Institutional research plan: CEZ:AV0Z50070508 Keywords : adipokinetic hormone * oxidative stress * GMO Subject RIV: ED - Physiology Impact factor: 2.368, year: 2007

  19. Endocrine therapy use among elderly hormone receptor-pos...

    U.S. Department of Health & Human Services — Clinical guidelines recommend that women with hormone-receptor positive breast cancer receive endocrine therapy (selective estrogen receptor modulators or aromatase...

  20. Role of adipokinetic peptides in control of insect anti-stress reactions

    Kodrík, Dalibor

    Vol. 13. Praha : Institute of Organic Chemistry and Biochemistry, 2011 - (Slaninová, J.; Valter, B.), s. 67-69 ISBN 978-80-86241-44-9. [Biologically Active Peptides. Conference /12./. Praha (CZ), 27.04.2011-29.04.2011] R&D Projects: GA ČR GAP501/10/1215 Institutional research plan: CEZ:AV0Z50070508 Keywords : Insect * adipokinetic hormone * stress Subject RIV: ED - Physiology

  1. Steroid hormone receptors in human salivary gland tumours.

    Lamey, P J; Leake, R. E.; Cowan, S K; Soutar, D S; McGregor, I. A.; McGregor, F M


    Major salivary gland tumours were studied for the presence of hormone receptors for oestrogen and progesterone. Of the eight salivary gland tumours exhibiting varied histology, none showed high affinity receptors for oestrogen or progesterone. Salivary tissue from four patients with non-neoplastic salivary gland disease was also studied and found not to contain high affinity receptor sites. The absence of hormone receptors in these glands suggests that such tumours are not dependent on endocr...

  2. Steroid Hormone Receptor Signals as Prognosticators for Urothelial Tumor

    Hiroki Ide


    Full Text Available There is a substantial amount of preclinical or clinical evidence suggesting that steroid hormone receptor-mediated signals play a critical role in urothelial tumorigenesis and tumor progression. These receptors include androgen receptor, estrogen receptors, glucocorticoid receptor, progesterone receptor, vitamin D receptor, retinoid receptors, peroxisome proliferator-activated receptors, and others including orphan receptors. In particular, studies using urothelial cancer tissue specimens have demonstrated that elevated or reduced expression of these receptors as well as alterations of their upstream or downstream pathways correlates with patient outcomes. This review summarizes and discusses available data suggesting that steroid hormone receptors and related signals serve as biomarkers for urothelial carcinoma and are able to predict tumor recurrence or progression.

  3. Thyroid hormone action in the absence of thyroid hormone receptor DNA-binding in vivo

    Shibusawa, Nobuyuki; Hashimoto, Koshi; Nikrodhanond, Amisra A.; Liberman, M. Charles; Applebury, Meredithe L.; Liao, Xiao Hui; Robbins, Janet T.; Refetoff, Samuel; Cohen, Ronald N.; Wondisford, Fredric E.


    Thyroid hormone action is mediated by thyroid hormone receptors (TRs), which are members of the nuclear hormone receptor superfamily. DNA-binding is presumed to be essential for all nuclear actions of thyroid hormone. To test this hypothesis in vivo, the DNA-binding domain of TR-β was mutated within its P-box (GS mutant) using gene targeting techniques. This mutation in vitro completely abolishes TR-β DNA-binding, while preserving ligand (T3) and cofactor interactions with the receptor. Homoz...

  4. Fast evolution of growth hormone receptor in primates and ruminants

    HOU Zhenfang; LI Ying; ZHANG Yaping


    Pituitary growth hormone (GH) evolves very slowly in most of mammals, but the evolutionary rates appear to have increased markedly on two occasions during the evolution of primates and ruminants. To investigate the evolutionary pattern of growth hormone receptor (GHR), we sequenced the extracellular domain of GHR genes from four primate species. Our results suggested that GHR in mammal also shows an episodic evolutionary pattern, which is consistent with that observed in pituitary growth hormone. Further analysis suggested that this pattern of rapid evolution observed in primates and ruminants is likely the result of coevolution between pituitary growth hormone and its receptor.

  5. The reciprocal regulation of stress hormones and GABAA receptors

    Istvan eMody


    Full Text Available Stress-derived steroid hormones regulate the expression and function of GABAA receptors (GABAARs. Changes in GABAAR subunit expression have been demonstrated under conditions of altered steroid hormone levels, such as stress, as well as following exogenous steroid hormone administration. In addition to the effects of stress-derived steroid hormones on GABAAR subunit expression, stress hormones can also be metabolized to neuroactive derivatives which can alter the function of GABAARs. Neurosteroids allosterically modulate GABAARs at concentrations comparable to those during stress. In addition to the actions of stress-derived steroid hormones on GABAARs, GABAARs reciprocally regulate the production of stress hormones. The stress response is mediated by the hypothalamic-pituitary-adrenal (HPA axis, the activity of which is governed by corticotropin releasing hormone (CRH neurons. The activity of CRH neurons is largely controlled by robust GABAergic inhibition. Recently, it has been demonstrated that CRH neurons are regulated by neurosteroid-sensitive, GABAAR δ subunit-containing receptors representing a novel feedback mechanism onto the HPA axis. Further, it has been demonstrated that neurosteroidogenesis and neurosteroid actions on GABAAR δ subunit-containing receptors on CRH neurons are necessary to mount the physiological response to stress. Here we review the literature describing the effects of steroid hormones on GABAARs as well as the importance of GABAARs in regulating the production of steroid hormones. This review incorporates what we currently know about changes in GABAARs following stress and the role in HPA axis regulation.

  6. Thyroid hormone receptor β mutants: Dominant negative regulators of peroxisome proliferator-activated receptor γ action

    Araki, Osamu; Ying, Hao; Furuya, Fumihiko; Zhu, Xuguang; Cheng, Sheue-yann


    Thyroid hormone (T3) and peroxisome proliferators have overlapping metabolic effects in the maintenance of lipid homeostasis. Their actions are mediated by their respective receptors: thyroid hormone receptors (TR) and peroxisome proliferator-activated receptors (PPAR). We recently found that a dominantly negative TRβ mutant (PV) that causes a genetic disease, resistance to thyroid hormone, acts to repress the ligand (troglitazone)-mediated transcriptional activity of PPARγ in cultured thyroi...

  7. Cloning of partial putative gonadotropin hormone receptor sequence from fish

    G Kumaresan; T Venugopal; A Vikas; T J Pandian; S M Athavan


    A search for the presence of mariner-like elements in the Labeo rohita genome by polymerase chain reaction led to the amplification of a partial DNA sequence coding for a putative transmembrane domain of gonadotropin hormone receptor. The amplified DNA sequence shows a high degree of homology to the available turkey and human luteinizing and follicle stimulating hormone receptor coding sequences. This is the first report on cloning such sequences of piscine origin.

  8. Activation of the chicken gonadotropin-inhibitory hormone receptor reduces gonadotropin releasing hormone receptor signaling.

    Shimizu, Mamiko; Bédécarrats, Grégoy Y


    Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic peptide from the RFamide peptide family that has been identified in multiple avian species. Although GnIH has clearly been shown to reduce LH release from the anterior pituitary gland, its mechanism of action remains to be determined. The overall objectives of this study were (1) to characterize the GnIH receptor (GnIH-R) signaling pathway, (2) to evaluate potential interactions with gonadotropin releasing hormone type III receptor (GnRH-R-III) signaling, and (3) to determine the molecular mechanisms by which GnIH and GnRH regulate pituitary gonadotrope function during a reproductive cycle in the chicken. Using real-time PCR, we showed that in the chicken pituitary gland, GnIH-R mRNA levels fluctuate in an opposite manner to GnRH-R-III, with higher and lower levels observed during inactive and active reproductive stages, respectively. We demonstrated that the chicken GnIH-R signals by inhibiting adenylyl cyclase cAMP production, most likely by coupling to G(alphai). We also showed that this inhibition is sufficient to significantly reduce GnRH-induced cAMP responsive element (CRE) activation in a dose-dependent manner, and that the ratio of GnRH/GnIH receptors is a significant factor. We propose that in avian species, sexual maturation is characterized by a change in GnIH/GnRH receptor ratio, resulting in a switch in pituitary sensitivity from inhibitory (involving GnIH) to stimulatory (involving GnRH). In turn, decreasing GnIH-R signaling, combined with increasing GnRH-R-III signaling, results in significant increases in CRE activation, possibly initiating gonadotropin synthesis. PMID:20350548

  9. Structural Basis for Antibody Discrimination between Two Hormones That Recognize the Parathyroid Hormone Receptor

    McKinstry, William J.; Polekhina, Galina; Diefenbach-Jagger, Hannelore; Ho, Patricia W.M.; Sato, Koh; Onuma, Etsuro; Gillespie, Matthew T.; Martin, T. John; Parker, Michael W.; (SVIMR-A); (Chugai); (Melbourne)


    Parathyroid hormone-related protein (PTHrP) plays a vital role in the embryonic development of the skeleton and other tissues. When it is produced in excess by cancers it can cause hypercalcemia, and its local production by breast cancer cells has been implicated in the pathogenesis of bone metastasis formation in that disease. Antibodies have been developed that neutralize the action of PTHrP through its receptor, parathyroid hormone receptor 1, without influencing parathyroid hormone action through the same receptor. Such neutralizing antibodies against PTHrP are therapeutically effective in animal models of the humoral hypercalcemia of malignancy and of bone metastasis formation. We have determined the crystal structure of the complex between PTHrP (residues 1-108) and a neutralizing monoclonal anti-PTHrP antibody that reveals the only point of contact is an {alpha}-helical structure extending from residues 14-29. Another striking feature is that the same residues that interact with the antibody also interact with parathyroid hormone receptor 1, showing that the antibody and the receptor binding site on the hormone closely overlap. The structure explains how the antibody discriminates between the two hormones and provides information that could be used in the development of novel agonists and antagonists of their common receptor.

  10. Palbociclib in Combination With Tamoxifen as First Line Therapy for Metastatic Hormone Receptor Positive Breast Cancer


    Hormone Receptor Positive Malignant Neoplasm of Breast; Human Epidermal Growth Factor 2 Negative Carcinoma of Breast; Estrogen Receptor Positive Breast Cancer; Progesterone Receptor Positive Tumor; Metastatic Breast Cancer

  11. Sex Steroid Hormone Receptor Expression Affects Ovarian Cancer Survival

    Jönsson, Jenny-Maria; Skovbjerg Arildsen, Nicolai; Malander, Susanne;


    BACKGROUND AND AIMS: Although most ovarian cancers express estrogen (ER), progesterone (PR), and androgen (AR) receptors, they are currently not applied in clinical decision making. We explored the prognostic impact of sex steroid hormone receptor protein and mRNA expression on survival in...

  12. Update of NUREBASE: nuclear hormone receptor functional genomics

    Ruau, David; Duarte, Jorge; Ourjdal, Tarik; Perrière, Guy; Laudet, Vincent; Robinson-Rechavi, Marc


    Nuclear hormone receptors are an abundant class of ligand-activated transcriptional regulators, found in varying numbers in all animals. Based on our experience of managing the official nomenclature of nuclear receptors, we have developed NUREBASE, a database containing protein and DNA sequences, reviewed protein alignments and phylogenies, taxonomy and annotations for all nuclear receptors. New developments in NUREBASE include explicit declaration of alternative transcripts of each gene, and...

  13. Resistance to Thyroid Hormone due to defective thyroid receptor alpha

    Moran, Carla; Chatterjee, Krishna


    Thyroid hormones act via nuclear receptors (TR?1, TR?1, TR?2) with differing tissue distribution; the role of ?2 protein, derived from the same gene locus as TR?1, is unclear. Resistance to thyroid hormone alpha (RTH?) is characterised by tissue-specific hypothyroidism associated with near-normal thyroid function tests. Clinical features include dysmorphic facies, skeletal dysplasia (macrocephaly, epiphyseal dysgenesis), growth retardation, constipation, dyspraxia and intellectual deficit...

  14. Five functional adipokinetic peptides expressed in the corpus cardiacum of the moth genus Hippotion (Lepidoptera, Sphingidae).

    Gäde, Gerd; Simek, Petr; Clark, Kevin D; Marco, Heather G


    This is the first study that finds five adipokinetic hormones (AKHs) in the corpus cardiacum of an insect. From two species of the sphingid moth genus Hippotion, eson and celerio, three novel and two known AKHs were isolated and sequenced by deduction from multiple MS(n) electrospray mass data: two octapeptides are pGlu-Leu-Thr-Phe-Thr-Ser-Ser-Trp amide (denoted Hipes-AKH-I) and its Thr(7) analogue (Hipes-AKH-II); two nonapeptides are pGlu-Leu-Thr-Phe-Thr-Ser-Ser-Trp-Gly amide (Manse-AKH) and its Thr(7) analogue (Hipes-AKH-III), as well as a decapeptide pGlu-Leu-Thr-Phe-Ser-Ser-Gly-Trp-Gly-Gln amide (Manse-AKH-II). All sequences were confirmed by identical behaviour of natural and synthetic peptides in reversed-phase HPLC and liquid chromatography coupled to electrospray mass spectrometry, resulting in identical retention times and tandem mass spectral data. High resolution mass spectrometry and retention time data also confirmed that the amino acid at position 10 in Manse-AKH-II is Gln and not the isobaric Lys. Conspecific injections of all five peptides in synthetic form and low doses caused hyperlipaemia in H. eson. Our results and pertaining literature suggest that five genes code for the mature peptides, which are very likely released during flight to provide energy for long distance migration in this genus via lipid oxidation; as all five peptides are active at low doses in a conspecific bioassay, it may be speculated, but not proven, that there is only one AKH receptor present in Hippotion that can bind all five peptides with high affinity. PMID:23541889

  15. Synthesis of Analogues of Thyroid Hormones: Nuclear Receptor Modulators

    Guilherme Vieira de Castro


    Full Text Available Thyroid hormones are essential for the development and differentiation of all cells of the human body. This work reports the synthesis of some synthetic structural analogues of thyroid hormones, which may be modulators of the thyroid hormone receptor. The known compounds GC-1 (Sobetirome and CG-24 were successfully prepared and two novel analogous molecules were also synthesized by a new and efficient synthetic methodology. DOI:  

  16. Thyroid hormone receptor binds to a site in the rat growth hormone promoter required for induction by thyroid hormone

    Transcription of the rat growth hormone (rGH) gene in pituitary cells is increased by addition of thyroid hormone (T3). This induction is dependent on the presence of specific sequences just upstream of the rGH promoter. The authors have partially purified T3 receptor from rat liver and examined its interaction with these rGH sequences. They show here that T3 receptor binds specifically to a site just upstream of the basal rGH promoter. This binding site includes two copies of a 7-base-pair direct repeat, the centers of which are separated by 10 base pairs. Deletions that specifically remove the T3 receptor binding site drastically reduce response to T3 in transient transfection experiments. These results demonstrate that T3 receptor can recognize specific DNA sequences and suggest that it can act directly as a positive transcriptional regulatory factor

  17. Model for growth hormone receptor activation based on subunit rotation within a receptor dimer

    Brown, Richard J.; Adams, Julian J.; Pelekanos, Rebecca A.; Wan, Yu; McKinstry, William J.; Palethorpe, Kathryn; Seeber, Ruth M.; Monks, Thea A.; Eidne, Karin A.; Parker, Michael W.; Waters, Michael J. (UWA); (St. Vincent); (Queensland)


    Growth hormone is believed to activate the growth hormone receptor (GHR) by dimerizing two identical receptor subunits, leading to activation of JAK2 kinase associated with the cytoplasmic domain. However, we have reported previously that dimerization alone is insufficient to activate full-length GHR. By comparing the crystal structure of the liganded and unliganded human GHR extracellular domain, we show here that there is no substantial change in its conformation on ligand binding. However, the receptor can be activated by rotation without ligand by inserting a defined number of alanine residues within the transmembrane domain. Fluorescence resonance energy transfer (FRET), bioluminescence resonance energy transfer (BRET) and coimmunoprecipitation studies suggest that receptor subunits undergo specific transmembrane interactions independent of hormone binding. We propose an activation mechanism involving a relative rotation of subunits within a dimeric receptor as a result of asymmetric placement of the receptor-binding sites on the ligand.


    Full Text Available FIELD NO 601751 FIELD TI 601751 MELANIN-CONCENTRATING HORMONE RECEPTOR 1; MCHR1 ;;G PROTEIN-COUP ... ted animals, and mice lacking MCH eat less and are lean . MCH antagonist might therefore provide a treatmen ... e. The null mice had normal body weights, yet were lean ... and had reduced fat mass. Surprisingly, the null m ...

  19. Ligand induction of a transcriptionally active thyroid hormone receptor coactivator complex.

    Fondell, J D; Ge, H.; Roeder, R G


    Transcriptional regulation by nuclear hormone receptors is thought to involve interactions with putative cofactors that may potentiate receptor function. Here we show that human thyroid hormone receptor alpha purified from HeLa cells grown in the presence of thyroid hormone (T3) is associated with a group of distinct nuclear proteins termed thyroid hormone receptor-associated proteins (TRAPs). In an in vitro system reconstituted with general initiation factors and cofactors (and in the absenc...

  20. Absence of serum growth hormone binding protein in patients with growth hormone receptor deficiency (Laron dwarfism).

    Daughaday, W H; Trivedi, B


    It has recently been recognized that human serum contains a protein that specifically binds human growth hormone (hGH). This protein has the same restricted specificity for hGH as the membrane-bound GH receptor. To determine whether the GH-binding protein is a derivative of, or otherwise related to, the GH receptor, we have examined the serum of three patients with Laron-type dwarfism, a condition in which GH refractoriness has been attributed to a defect in the GH receptor. The binding of 12...

  1. Expression of functional growth hormone receptor in a mouse L cell line infected with recombinant vaccinia virus

    Strous, G J; van Kerkhof, P; Verheijen, C; Rossen, J W; Liou, W; Slot, J W; Roelen, C A; Schwartz, A L


    The growth hormone receptor is a member of a large family of receptors including the receptors for prolactin and interleukins. Upon binding to one molecule of growth hormone two growth hormone receptor polypeptides dimerize. We have expressed the rabbit growth hormone receptor DNA in transfected mou

  2. Polypeptide hormone receptor phosphorylation: is there a role in receptor-mediated endocytosis of human growth hormone

    To determine whether receptor phosphorylation is a critical step in the internalization of polypeptide hormones and their receptors, the authors have studied a model system wherein insulin stimulates phosphorylation of its receptor and is also internalized. Using insulin as a positive control, they found that it stimulated a partially purified plasma membrane preparation of IM-9 lymphocytes to autophosphorylate its receptor and to catalyze the phosphorylation of a tyrosine-containing substrate. The human GH (hGH) receptor of the IM-9 lymphocytes, when coupled to [125I]iodo-hGH, migrated as a 140,000-dalton protein on polyacrylamide gel electrophoresis. This protein, in contrast to the insulin receptor, was not phosphorylated by the addition of hGH, nor did hGH stimulate this preparation to phosphorylate the tyrosine-containing substrate poly-(GluNa,Tyr)4:1, casein, or histone f2b under a variety of conditions. The authors conclude that receptor phosphorylation is not a critical intermediate in the receptor-mediated endocytosis of hGH and probably other polypeptide hormones and growth factors

  3. Molecular characterization of human thyroid hormone receptor β isoform 4.

    Moriyama, Kenji; Yamamoto, Hiroyuki; Futawaka, Kumi; Atake, Asami; Kasahara, Masato; Tagami, Tetsuya


    Thyroid hormone exerts a pleiotropic effect on development, differentiation, and metabolism through thyroid hormone receptor (TR). A novel thyroid hormone receptor β isoform (TRβ4) was cloned using PCR from a human pituitary cDNA library as a template. We report here the characterization of TRβ4 from a molecular basis. Temporal expression of TRβ4 during the fetal period is abundant in the brain and kidney, comparable with the adult pattern. Western blot analysis revealed that TRs are ubiquitination labile proteins, while TRβ1 is potentially stable. TRβ1, peroxisome proliferator-activated receptors (PPAR), and vitamin D receptor (VDR), which belong to class II transcription factors that function via the formation of heterodimeric complexes with retinoid X receptor (RXR), were suppressed by TRβ4 in a dose-dependent manner. Thus, TRβ4 exhibits ligand-independent transcriptional silencing, possibly as a substitute for dimerized RXR. In this study, TRβ1 and TRβ4 transcripts were detected in several cell lines. Quantitative RT-PCR assay showed that the expression of TRβ4 in human embryonic carcinoma cells of the testis was suppressed by sex hormone in a reciprocal manner to TRβ1. In contrast, TRβ4 was expressed under a high dose of triiodothyronine (T3) in a reciprocal manner to TRβ1. Finally, in transiently transfected NIH-3T3 cells, green fluorescence protein (GFP)-tagged TRβ4 was mostly nuclear in both the absence and the presence of T3. By mutating defined regions of both TRβs, we found that both TRβ1 and TRβ4 had altered nuclear/cytoplasmic distribution as compared with wild-type, and different to T3 and the nuclear receptor corepressor (NCoR). Thus, site-specific DNA binding is not essential for maintaining TRβs within the nucleus. PMID:26513165

  4. The Hinge Region of Human Thyroid-Stimulating Hormone (TSH) Receptor Operates as a Tunable Switch between Hormone Binding and Receptor Activation

    Majumdar, Ritankar; Dighe, Rajan R.


    The mechanism by which the hinge regions of glycoprotein hormone receptors couple hormone binding to activation of downstream effecters is not clearly understood. In the present study, agonistic (311.62) and antagonistic (311.87) monoclonal antibodies (MAbs) directed against the TSH receptor extracellular domain were used to elucidate role of the hinge region in receptor activation. MAb 311.62 which identifies the LRR/Cb-2 junction (aa 265-275), increased the affinity of TSHR for the hormone ...

  5. Prediction of nuclear hormone receptor response elements.

    Sandelin, Albin; Wasserman, Wyeth W


    The nuclear receptor (NR) class of transcription factors controls critical regulatory events in key developmental processes, homeostasis maintenance, and medically important diseases and conditions. Identification of the members of a regulon controlled by a NR could provide an accelerated understanding of development and disease. New bioinformatics methods for the analysis of regulatory sequences are required to address the complex properties associated with known regulatory elements targeted by the receptors because the standard methods for binding site prediction fail to reflect the diverse target site configurations. We have constructed a flexible Hidden Markov Model framework capable of predicting NHR binding sites. The model allows for variable spacing and orientation of half-sites. In a genome-scale analysis enabled by the model, we show that NRs in Fugu rubripes have a significant cross-regulatory potential. The model is implemented in a web interface, freely available for academic researchers, available at PMID:15563547

  6. Thyroid hormones and thyroid hormone receptors: Effects of thyromimetics on reverse cholesterol transport

    Matteo; Pedrelli; Camilla; Pramfalk; Paolo; Parini


    Reverse cholesterol transport (RCT) is a complex process which transfers cholesterol from peripheral cells to the liver for subsequent elimination from the body via feces. Thyroid hormones (THs) affect growth, develop- ment, and metabolism in almost all tissues. THs exert their actions by binding to thyroid hormone receptors (TRs). There are two major subtypes of TRs, TRα and TRβ, and several isoforms (e.g. TRα1, TRα2, TRβ1, and TRβ2). Activation of TRα1 affects heart rate, whereas activation of TRβ1 has po...

  7. Substantial expression of luteinizing hormone-releasing hormone (LHRH) receptor type I in human uveal melanoma

    Schally, Andrew V.; Block, Norman L; Dezso, Balazs; Olah, Gabor; Rozsa, Bernadett; Fodor, Klara; Buglyo, Armin; Gardi, Janos; Berta, Andras; Halmos, Gabor


    Uveal melanoma is the most common primary intraocular malignancy in adults, with a very high mortality rate due to frequent liver metastases. Consequently, the therapy of uveal melanoma remains a major clinical challenge and new treatment approaches are needed. For improving diagnosis and designing a rational and effective therapy, it is essential to elucidate molecular characteristics of this malignancy. The aim of this study therefore was to evaluate as a potential therapeutic target the expression of luteinizing hormone-releasing hormone (LHRH) receptor in human uveal melanoma. The expression of LHRH ligand and LHRH receptor transcript forms was studied in 39 human uveal melanoma specimens by RT-PCR using gene specific primers. The binding charachteristics of receptors for LHRH on 10 samples were determined by ligand competition assays. The presence of LHRH receptor protein was further evaluated by immunohistochemistry. The expression of mRNA for type I LHRH receptor was detected in 18 of 39 (46%) of tissue specimens. mRNA for LHRH-I ligand could be detected in 27 of 39 (69%) of the samples. Seven of 10 samples investigated showed high affinity LHRH-I receptors. The specific presence of full length LHRH receptor protein was further confirmed by immunohistochemistry. A high percentage of uveal melanomas express mRNA and protein for type-I LHRH receptors. Our results support the merit of further investigation of LHRH receptors in human ophthalmological tumors. Since diverse analogs of LHRH are in clinical trials or are already used for the treatment of various cancers, these analogs could be considered for the LHRH receptor-based treatment of uveal melanoma. PMID:24077773

  8. Sex Hormones and Their Receptors Regulate Liver Energy Homeostasis

    Minqian Shen


    Full Text Available The liver is one of the most essential organs involved in the regulation of energy homeostasis. Hepatic steatosis, a major manifestation of metabolic syndrome, is associated with imbalance between lipid formation and breakdown, glucose production and catabolism, and cholesterol synthesis and secretion. Epidemiological studies show sex difference in the prevalence in fatty liver disease and suggest that sex hormones may play vital roles in regulating hepatic steatosis. In this review, we summarize current literature and discuss the role of estrogens and androgens and the mechanisms through which estrogen receptors and androgen receptors regulate lipid and glucose metabolism in the liver. In females, estradiol regulates liver metabolism via estrogen receptors by decreasing lipogenesis, gluconeogenesis, and fatty acid uptake, while enhancing lipolysis, cholesterol secretion, and glucose catabolism. In males, testosterone works via androgen receptors to increase insulin receptor expression and glycogen synthesis, decrease glucose uptake and lipogenesis, and promote cholesterol storage in the liver. These recent integrated concepts suggest that sex hormone receptors could be potential promising targets for the prevention of hepatic steatosis.

  9. Homozygosity for a dominant negative thyroid hormone receptor gene responsible for generalized resistance to thyroid hormone.

    Ono, S; Schwartz, I D; Mueller, O T; Root, A W; Usala, S J; Bercu, B B


    Generalized resistance to thyroid hormones (GRTH) commonly results from mutations in the T3-binding domain of the c-erbA beta thyroid hormone receptor gene. We have reported on a novel deletion mutation in c-erbA beta in a kindred, S, with GRTH. One patient from this kindred was the product of a consanguineous union from two affected members and was homozygous for the beta-receptor defect. This patient at 3.5 weeks of age had unprecedented elevations of TSH, free T4, and free T3 (TSH, 389 mU/L; free T4, 330.8 pmol/L; free T3, 82,719 fmol/L). He displayed a complex mixture of tissue-specific hyperthyroidism and hypothyroidism. He had delayed growth (height age, 1 3/12 yr at chronological age 2 9/12 yr) and skeletal maturation (bone age, 4 months), and developmental delay (developmental age, 8 months), but he was quite tachycardic. The homozygous patient of kindred S is markedly different from a recently reported patient with no c-erbA beta-receptor. This difference indicates that a dominant negative form of c-erbA beta in man can inhibit at least some thyroid hormone action mediated by the c-erbA alpha-receptors. PMID:1682340

  10. Abnormal heart rate and body temperature in mice lacking thyroid hormone receptor alpha 1.

    Wikström, L; Johansson, C.; Saltó, C; C Barlow; Campos Barros, A; Baas, F.; Forrest, D; Thorén, P; Vennström, B


    Thyroid hormone, acting through several nuclear hormone receptors, plays important roles in thermogenesis, lipogenesis and maturation of the neonatal brain. The receptor specificity for mediating these effects is largely unknown, and to determine this we developed mice lacking the thyroid hormone receptor TR alpha 1. The mice have an average heart rate 20% lower than that of control animals, both under normal conditions and after thyroid hormone stimulation. Electrocardiograms show that the m...

  11. Thyroid hormone receptor can modulate retinoic acid-mediated axis formation in frog embryogenesis.

    Banker, D E; Eisenman, R N


    Thyroid hormone receptor acts as a hormone-dependent transcriptional transactivator and as a transcriptional repressor in the absence of thyroid hormone. Specifically, thyroid hormone receptor can repress retinoic acid-induced gene expression through interactions with retinoic acid receptor. (Retinoic acid is a potent teratogen in the frog Xenopus laevis, acting at early embryonic stages to interfere with the formation of anterior structures. Endogenous retinoic acid is thought to act in norm...

  12. Hormonal regulation of AMPA receptor trafficking and memory formation

    Harmen J Krugers


    Full Text Available Humans and rodents retain memories for stressful events very well. The facilitated retention of these memories is normally very useful. However, in susceptible individuals a variety of pathological conditions may develop in which memories related to stressful events remain inappropriately present, such as in post-traumatic stress disorder. The memory enhancing effects of stress are mediated by hormones, such as norepinephrine and glucocorticoids which are released during stressful experiences. Here we review recently identified molecular mechanisms that underlie the effects of stress hormones on synaptic efficacy and learning and memory. We discuss AMPA receptors as major target for stress hormones and describe a model in which norepinephrine and glucocorticoids are able to strengthen and prolong different phases of stressful memories.

  13. Affinity labeling of rat liver thyroid hormone nuclear receptor.

    Nikodem, V M; Cheng, S Y; Rall, J. E.


    The thyroid hormone receptor from rat liver nuclei has been covalently labeled with the N-bromoacetyl derivatives of L-thyroxine (T4) and 3,3',5-triiodo-L-thyronine (T3). Displacement binding studies showed that, in the presence of 100-fold molar excess of unlabeled N-bromoacetyl-T3 or T4, binding of [125I]T3 or [125I]T4 was nearly totally inhibited. Heat inactivation of the receptor (55 degrees C for 15 min) resulted in parallel losses in the binding of T3 (95%) and N-bromoacetyl-T3 (93%). T...

  14. Estrogen and Progesterone hormone receptor expression in oral cavity cancer

    Biegner, Thorsten; Teriete, Peter; Hoefert, Sebastian; Krimmel, Michael; Munz, Adelheid; Reinert, Siegmar


    Background Recent studies have shown an increase in the incidence of oral squamous cell carcinoma (OSCC) in younger patients. The hypothesis that tumors could be hormonally induced during pregnancy or in young female patients without the well-known risk factors alcohol or tobacco abuse seems to be plausible. Material and Methods Estrogen Receptor alpha (ERα) and Progesterone Receptor (PR) expression were analyzed in normal oral mucosa (n=5), oral precursor lesions (simple hyperplasia, n=11; squamous intraepithelial neoplasia, SIN I-III, n=35), and OSCC specimen. OSCCs were stratified in a young female (n=7) study cohort and older patients (n=46). In the young female study cohort three patients (n=3/7) developed OSCC during or shortly after pregnancy. Breast cancer tissues were used as positive control for ERα and PR expression. Results ERα expression was found in four oral precursor lesions (squamous intraepithelial neoplasia, SIN I-III, n=4/35, 11%) and in five OSCC specimen (n=5/46, 11%). The five ERα positive OSCC samples were older male patients. All patients within the young female study cohort were negatively stained for both ERα and PR. Conclusions ER expression could be regarded as a seldom risk factor for OSCC. PR expression seems to be not relevant for the development of OSCC. Key words:Oral squamous cell carcinoma, estrogen receptor, progesterone receptor, hormone receptor. PMID:27475696

  15. Regulation of growth hormone secretion by (pro)renin receptor

    Tani, Yuji; Yamada, Shozo; Inoshita, Naoko; Hirata, Yukio; SHICHIRI, MASAYOSHI


    (Pro)renin receptor (PRR) has a single transmembrane domain that co-purifies with the vacuolar H+-ATPase (V-ATPase). In addition to its role in cellular acidification, V-ATPase has been implicated in membrane fusion and exocytosis via its Vo domain. Results from the present study show that PRR is expressed in pituitary adenoma cells and regulates growth hormone (GH) release via V-ATPase-induced cellular acidification. Positive PRR immunoreactivity was detected more often in surgically resecte...

  16. Steroid/thyroid hormone receptor genes in Caenorhabditis elegans.

    Kostrouch, Z; Kostrouchova, M; Rall, J. E.


    The large family of steroid/thyroid hormone receptor (STR) genes has been extensively studied in vertebrates and insects but little information is available on it in more primitive organisms. All members possess a DNA binding domain of zinc fingers of the C2, C2 type. We have used the polymerase chain reaction with degenerate oligonucleotide primers covering this region to clone three distinct members of this family from the nematode Caenorhabditis elegans. All three belong to the retinoic ac...

  17. Radioreceptor assay for detergent-solubilized rat insulinoma growth hormone receptors

    Growth hormone receptors from a rat insulinoma cell line, RIN-5AH were solubilized in the non-ionic detergent Triton X-100. A radioreceptor assay based on polyethylene glycol precipitation of the growth hormone: receptor complex showed time-dependent and saturable hormone binding. The affinity in detergent solution for biosynthetic human growth hormone of approx. 6 ng/ml was found similar to that of intact RIN cells. The solubilization and receptor assay conditions described are useful for further characterization and purification of RIN cell growth hormone receptors, which might provide an initial insight into the molecular mechanism of the growth effects on islet β-cells. (author)

  18. Radioiodination of chicken luteinizing hormone without affecting receptor binding potency

    By improving the currently used lactoperoxidase method, we were able to obtain radioiodinated chicken luteinizing hormone (LH) that shows high specific binding and low nonspecific binding to a crude plasma membrane fraction of testicular cells of the domestic fowl and the Japanese quail, and to the ovarian granulosa cells of the Japanese quail. The change we made from the original method consisted of (1) using chicken LH for radioiodination that was not only highly purified but also retained a high receptor binding potency; (2) controlling the level of incorporation of radioiodine into chicken LH molecules by employing a short reaction time and low temperature; and (3) fractionating radioiodinated chicken LH further by gel filtration using high-performance liquid chromatography. Specific radioactivity of the final 125I-labeled chicken LH preparation was 14 microCi/micrograms. When specific binding was 12-16%, nonspecific binding was as low as 2-4% in the gonadal receptors. 125I-Labeled chicken LH was displaced by chicken LH and ovine LH but not by chicken follicle-stimulating hormone. The equilibrium association constant of quail testicular receptor was 3.6 x 10(9) M-1. We concluded that chicken LH radioiodinated by the present method is useful for studies of avian LH receptors

  19. Growth hormone-dependent phosphorylation of tyrosine 333 and/or 338 of the growth hormone receptor

    VanderKuur, J A; Wang, X; Zhang, L;


    Many signaling pathways initiated by ligands that activate receptor tyrosine kinases have been shown to involve the binding of SH2 domain-containing proteins to specific phosphorylated tyrosines in the receptor. Although the receptor for growth hormone (GH) does not contain intrinsic tyrosine...

  20. Evolution of gonadotropin-inhibitory hormone receptor and its ligand.

    Ubuka, Takayoshi; Tsutsui, Kazuyoshi


    Gonadotropin-inhibitory hormone (GnIH) is a neuropeptide inhibitor of gonadotropin secretion, which was first identified in the Japanese quail hypothalamus. GnIH peptides share a C-terminal LPXRFamide (X=L or Q) motif in most vertebrates. The receptor for GnIH (GnIHR) is the seven-transmembrane G protein-coupled receptor 147 (GPR147) that inhibits cAMP production. GPR147 is also named neuropeptide FF (NPFF) receptor 1 (NPFFR1), because it also binds NPFF that has a C-terminal PQRFamide motif. To understand the evolutionary history of the GnIH system in the animal kingdom, we searched for receptors structurally similar to GnIHR in the genome of six mammals (human, mouse, rat, cattle, cat, and rabbit), five birds (pigeon, chicken, turkey, budgerigar, and zebra finch), one reptile (green anole), one amphibian (Western clawed flog), six fishes (zebrafish, Nile tilapia, Fugu, coelacanth, spotted gar, and lamprey), one hemichordate (acorn worm), one echinoderm (purple sea urchin), one mollusk (California sea hare), seven insects (pea aphid, African malaria mosquito, honey bee, buff-tailed bumblebee, fruit fly, jewel wasp, and red flour beetle), one cnidarian (hydra), and constructed phylogenetic trees by neighbor joining (NJ) and maximum likelihood (ML) methods. A multiple sequence alignment of the receptors showed highly conserved seven-transmembrane domains as well as disulfide bridge sites between the first and second extracellular loops, including the receptor of hydra. Both NJ and ML analyses grouped the receptors of vertebrates into NPFFR1 and NPFFR2 (GPR74), and the receptors of insects into the receptor for SIFamide peptides that share a C-terminal YRKPPFNGSIFamide motif. Although human, quail and zebrafish GnIHR (NPFFR1) were most structurally similar to SIFamide receptor of fruit fly in the Famide peptide (FMRFamide, neuropeptide F, short neuropeptide F, drosulfakinin, myosuppressin, SIFamide) receptor families, the amino acid sequences and the peptide coding

  1. Characterization of a thyroid hormone receptor expressed in human kidney and other tissues

    A cDNA encoding a specific form of thyroid hormone receptor expressed in human liver, kidney, placenta, and brain was isolated from a human kidney library. Identical clones were found in human placenta and HepG2 cDNA libraries. The cDNA encodes a 490-amino acid protein. When expressed and translated in vitro, the protein products binds triiodothyronine with K/sub a/ of 2.3 /times/ 109 M/sup /minus/1/. This protein, designated human thyroid hormone receptor type α2 (hTRα2), has the same domain structure as other members of the v-erbA-related superfamily of receptor genes. It is similar to thyroid hormone receptor type α described in chicken and rat and less similar to human thyroid hormone receptor type β (formerly referred to as c-erbAβ) from placenta. However, it is distinguished from these receptors by an extension of the C-terminal hormone binding domain making it 80 amino acids longer than rat thyroid hormone receptor type α1. Different sizes of mRNA found in liver and kidney suggest that there may be tissue-specific processing of the primary transcript of this gene. Identification of human thyroid hormone receptor type α2 indicates that two or more forms of thyroid hormone receptor exist in human tissues and may explain the normal variation in thyroid hormone responsiveness of various organs and the selective tissue abnormalities found in the thyroid hormone resistance syndromes

  2. RXR alpha, a promiscuous partner of retinoic acid and thyroid hormone receptors.

    Bugge, T H; Pohl, J.; Lonnoy, O; Stunnenberg, H G


    Retinoic acid receptor (RAR), thyroid hormone receptor (T3R) and vitamin D3 receptor (VD3R) differ from steroid hormone receptors in that they bind and transactivate through responsive elements organized as direct rather than inverted repeats. We now show that recombinant RAR and T3R are monomers in solution and cannot form stable homodimeric complexes on their responsive elements. Stable binding of the receptors to their responsive elements requires heterodimerization with a nuclear factor. ...

  3. Receptor guanylyl cyclases in Inka cells targeted by eclosion hormone.

    Chang, Jer-Cherng; Yang, Ruey-Bing; Adams, Michael E; Lu, Kuang-Hui


    A signature of eclosion hormone (EH) action in insect ecdysis is elevation of cGMP in Inka cells, leading to massive release of ecdysis triggering hormone (ETH) and ecdysis initiation. Although this aspect of EH-induced signal transduction is well known, the receptor mediating this process has not been identified. Here, we describe a receptor guanylyl cyclase BdmGC-1 and its isoform BdmGC-1B in the Oriental fruit fly Bactrocera dorsalis that are activated by EH. The B form exhibits the conserved domains and putative N-glycosylation sites found in BdmGC-1, but possesses an additional 46-amino acid insertion in the extracellular domain and lacks the C-terminal tail of BdmGC-1. Combined immunolabeling and in situ hybridization reveal that BdmGC-1 is expressed in Inka cells. Heterologous expression of BdmGC-1 in HEK cells leads to robust increases in cGMP following exposure to low picomolar concentrations of EH. The B-isoform responds only to higher EH concentrations, suggesting different physiological roles of these cyclases. We propose that BdmGC-1 and BdmGC-1B are high- and low-affinity EH receptors, respectively. PMID:19666575

  4. Critical role for thyroid hormone receptor β2 in the regulation of paraventricular thyrotropin-releasing hormone neurons

    Abel, E. Dale; Ahima, Rexford S.; Boers, Mary-Ellen; Elmquist, Joel K.; Wondisford, Fredric E.


    Thyroid hormone thyroxine (T4) and tri-iodothyronine (T3) production is regulated by feedback inhibition of thyrotropin (TSH) and thyrotropin-releasing hormone (TRH) synthesis in the pituitary and hypothalamus when T3 binds to thyroid hormone receptors (TRs) interacting with the promoters of the genes for the TSH subunit and TRH. All of the TR isoforms likely participate in the negative regulation of TSH production in vivo, but the identity of the specific TR isoforms that negatively regulate...

  5. Detection of two growth hormone receptor mRNAs and primary translation products in the mouse

    Smith, W.C.; Linzer, D I; Talamantes, F


    Two mouse growth hormone-receptor primary translation products of Mr 95,900 and 31,800 were identified from in vitro-translated late pregnant mouse liver mRNA. RNA isolated from mouse liver was translated in a rabbit reticulocyte lysate system containing [35S]methionine, and the growth hormone receptor primary translation products were identified by immunoprecipitation with anti-mouse growth hormone receptor antiserum followed by sodium dodecyl sulfate/PAGE and fluorography. Detectable amount...

  6. Luteinizing hormone-releasing hormone receptor-mediated delivery of mitoxantrone using LHRH analogs modified with PEGylated liposomes

    Sun, Hongfan


    Yingna He, Linhua Zhang, Cunxian SongKey Laboratory of Biomedical Material of Tianjin, Institute of Biomedical Engineering, Peking Union Medical College and Chinese Academy of Medical Sciences, Tianjin, ChinaAbstract: A sterically stabilized, mitoxantrone-loaded liposome, tailored to target luteinizing hormone-releasing hormone (LHRH) receptor overexpressing cells, was developed to promote the efficiency of intracellular delivery of mitoxantrone through receptor-mediated endocytosis. Liposome...

  7. Cell Cycle-dependent Expression of Thyroid Hormone Receptor-β Is a Mechanism for Variable Hormone SensitivityD⃞

    Maruvada, Padma; Dmitrieva, Natalia I.; East-Palmer, Joyce; Yen, Paul M.


    Thyroid hormone receptors (TRs) are ligand-regulatable transcription factors. Currently, little is known about the expression of TRs or other nuclear hormone receptors during the cell cycle. We thus developed a stable expression system to express green fluorescent protein-TRβ in HeLa cells under tetracycline regulation, and studied TR expression during the cell cycle by laser scanning cytometry. Only ∼9-15% of the nonsynchronized cell population expressed TR because the majority of cells were...

  8. The liver taxis of receptor mediated lactosaminated human growth hormone

    Radiography imaging is used to assess liver taxis mechanism of anti-dwarfism drug lactosaminated human growth hormone (L-rhGH). Both L-rhGH and rhGH labelled with 131I are used to study their biodistribution in animals (including rabbits, cocks and rats). The results show that L-rhGH is of specific hepatic targeting property, and the maximum hepatic concentration rate is 76.8%, which is two times of rhGH. Its hepatic binding is receptor mediated

  9. Introduction of exogenous growth hormone receptors augments growth hormone-responsive insulin biosynthesis in rat insulinoma cells.

    Billestrup, N; Møldrup, A; Serup, P.; Mathews, L S; Norstedt, G; Nielsen, J H


    The stimulation of insulin biosynthesis in the pancreatic insulinoma cell line RIN5-AH by growth hormone (GH) is initiated by GH binding to specific receptors. To determine whether the recently cloned rat hepatic GH receptor is able to mediate the insulinotropic effect of GH, we have transfected a GH receptor cDNA under the transcriptional control of the human metallothionein promoter into RIN5-AH cells. The transfected cells were found to exhibit an increased expression of GH receptors and t...

  10. Growth hormone action in rat insulinoma cells expressing truncated growth hormone receptors

    Møldrup, Annette; Allevato, G; Dyrberg, Thomas;


    Transfection of the insulin-producing rat islet tumor cell line RIN-5AH with a full length cDNA of the rat hepatic growth hormone (GH) receptor (GH-R1-638) augments the GH-responsive insulin synthesis in these cells. Using this functional system we analyzed the effect of COOH-terminal truncation of...... the GH receptor. Two mutated cDNAs encoding truncated GH receptors, GH-R1-294 and GH-R1-454, respectively, were generated by site-directed mutagenesis and transfected into the RIN cells. Both receptor mutants were expressed on the cell surface and displayed normal GH binding affinity. Whereas GH-R1......-638 had a molecular mass of about 110 kDa, GH-R1-294 and GH-R1-454 showed molecular masses of 49 and 80 kDa, respectively. Cells expressing GH-R1-454 internalized GH to a similar extent as cells transfected with the full length receptor and the parent cell line, but GH-R1-294-expressing cells showed a...

  11. The androgen receptor in hormone-refractory prostate cancer

    Hai-Lei Mao; Zhi-Qi Zhu; Charlie Degui Chen


    Advanced prostate cancer is responsive to hormone therapy that interferes with androgen receptor (AR) signalling.However,the effect is short-lived,as nearly all tumours progress to a hormone-refractory (HR) state,a lethal stage of the disease.Intuitively,the AR should not be involved because hormone therapy that blocks or reduces AR activity is not effective in treating HR turnouts.However,there is still a consensus that AR plays an essential role in HR prostate cancer (HRPC) because AR signalling is still functional in HR tumours.AR signalling can be activated in HR turnouts through several mechanisms.First,activation of intracellular signal transduction pathways can sensitize the AR to castrate levels of androgens.Also,mutations in the AR can change AR ligand specificity,thereby allowing it to be activated by non-steroids or anti-androgens.Finally,overexpression of the wild-type AR sensitizes itself to low concentrations of androgens.Therefore,drugs targeting AR signalling could still be effective in treating HRPC.

  12. Binding of 125I-human growth hormone to specific receptors in human cultured lymphocytes

    The interaction of human growth hormone with human lymphocytes from an established culture (IM-9) was studied using 125I- human growth hormone. The binding of 125I-human growth hormone was rapid; with human growth hormone at 0.1 nM a steady state was observed in 90 min at 300. Bound labeled human growth hormone was dissociated rapidly by addition of excess unlabeled human growth hormone. Binding of 125I-human growth hormone to cultured lymphocytes was relatively insensitive to alterations in the pH and in the concentrations of Ca2+, Mg2+, EDTA. At 800 there was very little degradation of labeled human growth hormone or of the specific receptor sites. Tryptic digestion destroyed the capacity of cells to bind human growth hormone. The IM-9 cells bound all human growth hormone preparations but not unrelated hormones or nonprimate growth hormones. The binding of 125I-human growth hormone was inhibited 10 to 14 percent with 1 to 2 ng per ml of unlabeled human growth hormone and 50 percent with 30 to 40 ng per ml, well within the range of hormone concentrations in vivo. Analysis of steady state data revealed a single order of binding sites with an affinity constant of 1.3 x 109 M-1 and about 4000 binding sites per cell. Numerous human growth hormone preparations were assayed by use of this receptor system as well as by immunoassay and by bioassay in vivo. The po

  13. The thyroid hormone receptors modulate the skin response to retinoids.

    Laura García-Serrano

    Full Text Available BACKGROUND: Retinoids play an important role in skin homeostasis and when administered topically cause skin hyperplasia, abnormal epidermal differentiation and inflammation. Thyroidal status in humans also influences skin morphology and function and we have recently shown that the thyroid hormone receptors (TRs are required for a normal proliferative response to 12-O-tetradecanolyphorbol-13-acetate (TPA in mice. METHODOLOGY/PRINCIPAL FINDINGS: We have compared the epidermal response of mice lacking the thyroid hormone receptor binding isoforms TRα1 and TRβ to retinoids and TPA. Reduced hyperplasia and a decreased number of proliferating cells in the basal layer in response to 9-cis-RA and TPA were found in the epidermis of TR-deficient mice. Nuclear levels of proteins important for cell proliferation were altered, and expression of keratins 5 and 6 was also reduced, concomitantly with the decreased number of epidermal cell layers. In control mice the retinoid (but not TPA induced parakeratosis and diminished expression of keratin 10 and loricrin, markers of early and terminal epidermal differentiation, respectively. This reduction was more accentuated in the TR deficient animals, whereas they did not present parakeratosis. Therefore, TRs modulate both the proliferative response to retinoids and their inhibitory effects on skin differentiation. Reduced proliferation, which was reversed upon thyroxine treatment, was also found in hypothyroid mice, demonstrating that thyroid hormone binding to TRs is required for the normal response to retinoids. In addition, the mRNA levels of the pro-inflammatory cytokines TNFα and IL-6 and the chemotactic proteins S1008A and S1008B were significantly elevated in the skin of TR knock-out mice after TPA or 9-cis-RA treatment and immune cell infiltration was also enhanced. CONCLUSIONS/SIGNIFICANCE: Since retinoids are commonly used for the treatment of skin disorders, these results demonstrating that TRs

  14. The Neuroendocrine Functions of the Parathyroid Hormone 2 Receptor

    Arpad eDobolyi


    Full Text Available The G-protein coupled parathyroid hormone 2 receptor (PTH2R is concentrated in endocrine and limbic regions in the forebrain. Its endogenous ligand,tuberoinfundibular peptide of 39 residues (TIP39, is synthesized in only 2 brain regions, within the posterior thalamus and the lateral pons. TIP39-expressing neurons have a widespread projection pattern, which matches the PTH2R distribution in the brain. Neuroendocrine centers including the preoptic area, the periventricular, paraventricular, and arcuate nuclei contain the highest density of PTH2R-positive networks. The administration of TIP39 and an antagonist of the PTH2R as well as the investigation of mice that lack functional TIP39 and PTH2R revealed the involvement of the PTH2R in a variety of neural and neuroendocrine functions. TIP39 acting via the PTH2R modulates several aspects of the stress response. It evokes corticosterone release by activating corticotropin-releasing hormone-containing neurons in the hypothalamic paraventricular nucleus. Block of TIP39 signaling elevates the anxiety state of animals and their fear response, and increases stress-induced analgesia. TIP39 has also been suggested to affect the release of additional pituitary hormones including arginine vasopressin and growth hormone. A role of the TIP39-PTH2R system in thermoregulation was also identified. TIP39 may play a role in maintaining body temperature in a cold environment via descending excitatory pathways from the preoptic area. Anatomical and functional studies also implicated the TIP39-PTH2R system in nociceptive information processing. Finally, TIP39 induced in postpartum dams may play a role in the release of prolactin during lactation. Potential mechanisms leading to the activation of TIP39 neurons and how they influence the neuroendocrine system are also described. The unique TIP39-PTH2R neuromodulator system provides the possibility for developing drugs with a novel mechanism of action to control

  15. Introduction of exogenous growth hormone receptors augments growth hormone-responsive insulin biosynthesis in rat insulinoma cells

    Billestrup, N; Møldrup, A; Serup, P;


    The stimulation of insulin biosynthesis in the pancreatic insulinoma cell line RIN5-AH by growth hormone (GH) is initiated by GH binding to specific receptors. To determine whether the recently cloned rat hepatic GH receptor is able to mediate the insulinotropic effect of GH, we have transfected ...

  16. The Role of the Enterohepatic Circulation of Bile Salts and Nuclear Hormone Receptors in the Regulation of Cholesterol Homeostasis: Bile Salts as Ligands for Nuclear Hormone Receptors

    Redinger, Richard N.


    The coordinated effect of lipid activated nuclear hormone receptors; liver X receptor (LXR), bound by oxysterol ligands and farnesoid X receptor (FXR), bound by bile acid ligands, act as genetic transcription factors to cause feed-forward cholesterol catabolism to bile acids and feedback repression of bile acid synthesis, respectively. It is the coordinated action of LXR and FXR, each dimerized to retinoid X receptor, that signal nuclear DNA response elements to encode proteins that prevent e...

  17. Evidence for association of the cloned liver growth hormone receptor with a tyrosine kinase

    Wang, X; Uhler, M D; Billestrup, N;


    The ability of the cloned liver growth hormone (GH) receptor, when expressed in mammalian cell lines, to copurify with tyrosine kinase activity and be tyrosyl phosphorylated was examined. 125I-human growth hormone-GH receptor complexes isolated from COS-7 cells transiently expressing high levels...

  18. Direct and in vitro observation of growth hormone receptor molecules in A549 human lung epithelial cells by nanodiamond labeling

    Cheng, C.-Y.; Perevedentseva, E.; Tu, J.-S.; Chung, P.-H.; Cheng, C.-L.; Liu, K.-K.; Chao, J.-I.; Chen, P.-H.; Chang, C.-C.


    This letter presents direct observation of growth hormone receptor in one single cancer cell using nanodiamond-growth hormone complex as a specific probe. The interaction of surface growth hormone receptor of A549 human lung epithelial cells with growth hormone was observed using nanodiamond's unique spectroscopic signal via confocal Raman mapping. The growth hormone molecules were covalent conjugated to 100nm diameter carboxylated nanodiamonds, which can be recognized specifically by the growth hormone receptors of A549 cell. The Raman spectroscopic signal of diamond provides direct and in vitro observation of growth hormone receptors in physiology condition in a single cell level.

  19. Rapid signaling at the plasma membrane by a nuclear receptor for thyroid hormone

    Storey, Nina M.; Gentile, Saverio; Ullah, Hemayet; Russo, Angela; Muessel, Michelle; Erxleben, Christian; Armstrong, David L.


    Many nuclear hormones have physiological effects that are too rapid to be explained by changes in gene expression and are often attributed to unidentified or novel G protein-coupled receptors. Thyroid hormone is essential for normal human brain development, but the molecular mechanisms responsible for its effects remain to be identified. Here, we present direct molecular evidence for potassium channel stimulation in a rat pituitary cell line (GH4C1) by a nuclear receptor for thyroid hormone, ...

  20. Analysis of estrogen receptor transcriptional enhancement by a nuclear hormone receptor coactivator.

    McInerney, E M; Tsai, M J; O'Malley, B W; Katzenellenbogen, B S


    The estrogen receptor (ER), a member of a large superfamily of nuclear hormone receptors, is a ligand-inducible transcription factor that regulates the expression of estrogen-responsive genes. The ER, in common with other members of this superfamily, contains two transcription activation functions (AFs)--one located in the amino-terminal region (AF-1) and the second located in the carboxyl-terminal region (AF-2). In most cell contexts, the synergistic activity of AF-1 and AF-2 is required for...

  1. Retinoid X Receptor Regulates Nur77/Thyroid Hormone Receptor 3-Dependent Apoptosis by Modulating Its Nuclear Export and Mitochondrial Targeting

    Cao, Xihua; Liu, Wen; Lin, Feng; Li, Hui; Kolluri, Siva Kumar; Lin, Bingzhen; Han, Young-Hoon; Dawson, Marcia I.; Zhang, Xiao-kun


    Retinoid X receptor (RXR) plays a central role in the regulation of intracellular receptor signaling pathways by acting as a ubiquitous heterodimerization partner of many nuclear receptors, including the orphan receptor Nur77 (also known as thyroid hormone receptor 3 or NGFI-B), which translocates from the nucleus to mitochondria, where it interacts with Bcl-2 to induce apoptosis. Here, we report that RXRα is required for nuclear export and mitochondrial targeting of Nur77 through their uniqu...

  2. Thyrotropin-luteinizing hormone/chorionic gonadotropin receptor extracellular domain chimeras as probes for thyrotropin receptor function.

    Nagayama, Y; Wadsworth, H L; Chazenbalk, G D; Russo, D.; Seto, P; Rapoport, B


    To define the sites in the extracellular domain of the human thyrotropin (TSH) receptor that are involved in TSH binding and signal transduction we constructed chimeric thyrotropin-luteinizing hormone/chorionic gonadotropin (TSH-LH/CG) receptors. The extracellular domain of the human TSH receptor was divided into five regions that were replaced, either singly or in various combinations, with homologous regions of the rat LH/CG receptor. The chimeric receptors were stably expressed in Chinese ...

  3. Resistance to thyroid hormone due to defective thyroid receptor alpha.

    Moran, Carla; Chatterjee, Krishna


    Thyroid hormones act via nuclear receptors (TRα1, TRβ1, TRβ2) with differing tissue distribution; the role of α2 protein, derived from the same gene locus as TRα1, is unclear. Resistance to thyroid hormone alpha (RTHα) is characterised by tissue-specific hypothyroidism associated with near-normal thyroid function tests. Clinical features include dysmorphic facies, skeletal dysplasia (macrocephaly, epiphyseal dysgenesis), growth retardation, constipation, dyspraxia and intellectual deficit. Biochemical abnormalities include low/low-normal T4 and high/high-normal T3 concentrations, a subnormal T4/T3 ratio, variably reduced reverse T3, raised muscle creatine kinase and mild anaemia. The disorder is mediated by heterozygous, loss-of-function, mutations involving either TRα1 alone or both TRα1 and α2, with no discernible phenotype attributable to defective α2. Whole exome sequencing and diagnostic biomarkers may enable greater ascertainment of RTHα, which is important as thyroxine therapy reverses some metabolic abnormalities and improves growth, constipation, dyspraxia and wellbeing. The genetic and phenotypic heterogeneity of RTHα and its optimal management remain to be elucidated. PMID:26303090

  4. Gene specific actions of thyroid hormone receptor subtypes.

    Jean Z Lin

    Full Text Available There are two homologous thyroid hormone (TH receptors (TRs α and β, which are members of the nuclear hormone receptor (NR family. While TRs regulate different processes in vivo and other highly related NRs regulate distinct gene sets, initial studies of TR action revealed near complete overlaps in their actions at the level of individual genes. Here, we assessed the extent that TRα and TRβ differ in target gene regulation by comparing effects of equal levels of stably expressed exogenous TRs +/- T(3 in two cell backgrounds (HepG2 and HeLa. We find that hundreds of genes respond to T(3 or to unliganded TRs in both cell types, but were not able to detect verifiable examples of completely TR subtype-specific gene regulation. TR actions are, however, far from identical and we detect TR subtype-specific effects on global T(3 response kinetics in HepG2 cells and many examples of TR subtype specificity at the level of individual genes, including effects on magnitude of response to TR +/- T(3, TR regulation patterns and T(3 dose response. Cycloheximide (CHX treatment confirms that at least some differential effects involve verifiable direct TR target genes. TR subtype/gene-specific effects emerge in the context of widespread variation in target gene response and we suggest that gene-selective effects on mechanism of TR action highlight differences in TR subtype function that emerge in the environment of specific genes. We propose that differential TR actions could influence physiologic and pharmacologic responses to THs and selective TR modulators (STRMs.

  5. Role of the extracellular and intracellular loops of follicle stimulating hormone receptor in its function

    Antara A Banerjee


    Full Text Available Follicle stimulating hormone receptor (FSHR is a leucine rich repeat containing class A G-protein coupled receptor belonging to the subfamily of glycoprotein hormone receptors, which includes luteinizing hormone/choriogonadotropin receptor (LH/CGR and thyroid stimulating hormone receptor (TSHR. Its cognate ligand, follicle stimulating hormone (FSH binds to and activates FSHR expressed on the surface of granulosa cells of the ovary, in females, and Sertoli cells of the testis, in males, to bring about folliculogenesis and spermatogenesis, respectively. FSHR contains a large extracellular domain (ECD consisting of leucine rich repeats at the N-terminal end and a hinge region at the C-terminus that connects the ECD to the membrane spanning transmembrane domain (TMD. The TMD consists of seven α-helices that are connected to each other by means of three extracellular loops (ELs and three intracellular loops (ILs and ends in a short cytoplasmic tail. It is well established that the extracellular domain (ECD is the primary hormone binding domain, whereas the TMD is the signal transducing domain. However, several studies on the ELs and ILs employing site directed mutagenesis, generation of chimeric receptors and in vitro characterization of naturally occurring mutations have proven their indispensable role in FSHR function. Their role in every phase of the life cycle of the receptor like post translational modifications, cell surface trafficking, hormone binding, activation of downstream signaling, receptor phosphorylation, hormone-receptor internalization, recycling of hormone receptor complex have been documented. Mutations in the loops causing dysregulation of these processes lead to pathophysiological conditions. In other GPHRs as well, the loops have been convincingly shown to contribute to various aspects of receptor function. This review article attempts to summarize the extensive contributions of FSHR loops and C-terminal tail to its function.

  6. (−) Arctigenin and (+) Pinoresinol Are Antagonists of the Human Thyroid Hormone Receptor β

    Ogungbe, Ifedayo Victor; Crouch, Rebecca A.; Demeritte, Teresa


    Lignans are important biologically active dietary polyphenolic compounds. Consumption of foods that are rich in lignans is associated with positive health effects. Using modeling tools to probe the ligand-binding pockets of molecular receptors, we found that lignans have high docking affinity for the human thyroid hormone receptor β. Follow-up experimental results show that lignans (−) arctigenin and (+) pinoresinol are antagonists of the human thyroid hormone receptor β. The modeled complexe...

  7. Sex Steroid Hormone Receptor Expression Affects Ovarian Cancer Survival

    Jenny-Maria Jönsson


    Full Text Available Background and Aims: Although most ovarian cancers express estrogen (ER, progesterone (PR, and androgen (AR receptors, they are currently not applied in clinical decision making. We explored the prognostic impact of sex steroid hormone receptor protein and mRNA expression on survival in epithelial ovarian cancer. Methods: Immunohistochemical stainings for ERα, ERβ, PR, and AR were assessed in relation to survival in 118 serous and endometrioid ovarian cancers. Expression of the genes encoding the four receptors was studied in relation to prognosis in the molecular subtypes of ovarian cancer in an independent data set, hypothesizing that the expression levels and prognostic impact may differ between the subtypes. Results: Expression of PR or AR protein was associated with improved 5-year progression-free (P = .001 for both and overall survival (P < .001 for both, log-rank test. ERα and ERβ did not provide prognostic information. Patients whose tumors coexpressed PR and AR had the most favorable prognosis, and this effect was retained in multivariable analyses. Analyses of the corresponding genes using an independent data set revealed differences among the molecular subtypes, but no clear relationship between high coexpression of PGR and AR and prognosis. Conclusions: A favorable outcome was seen for patients whose tumors coexpressed PR and AR. Gene expression data suggested variable effects in the different molecular subtypes. These findings demonstrate a prognostic role for PR and AR in ovarian cancer and support that tumors should be stratified based on molecular as well as histological subtypes in future studies investigating the role of endocrine treatment in ovarian cancer.

  8. CHHBP: a newly identified receptor of crustacean hyperglycemic hormone.

    Li, Ran; Tian, Jin-Ze; Zhuang, Cui-Heng; Zhang, Yi-Chen; Geng, Xu-Yun; Zhu, Li-Na; Sun, Jin-Sheng


    Crustacean hyperglycemic hormone (CHH) is a neurohormone found only in arthropods that plays a pivotal role in the regulation of hemolymph glucose levels, molting and stress responses. Although it was determined that a membrane guanylyl cyclase (GC) acts as the CHH receptor in the Y-organ during ecdysteroidogenesis, the identity of the CHH receptor in the hepatopancreas has not been established. In this study, we identified CHH binding protein (CHHBP), as a potential receptor by screening the annotated unigenes from the transcriptome of ITALIC! Eriocheir sinensis, after removal of the eyestalk. Analysis of the binding affinity between CHH and CHHBP provided direct evidence that CHH interacts with CHHBP in a specific binding mode. Subsequent analysis showed that CHHBP is expressed primarily in the hepatopancreas where it localizes to the cell membrane. In addition, real-time PCR analysis showed that ITALIC! CHHBPtranscript levels gradually increase in the hepatopancreas following eyestalk ablation. RNAi-mediated suppression of ITALIC! CHHBPexpression resulted in decreased glucose levels. Furthermore, the reduction of blood glucose induced by ITALIC! CHHBPRNAi reached the same level as that observed in the eyestalk ablation group, suggesting that CHHBP is involved in glucose metabolism regulated by CHH. In addition, compared with the control group, injection of CHH was unable to rescue the decreased glucose levels in ITALIC! CHHBPRNAi crabs. CHH induced transport of 2-NBDG to the outside of cells, with indispensable assistance from CHHBP. Taken together, these findings suggest that CHHBP acts as one type of the primary signal processor of CHH-mediated regulation of cellular glucose metabolism. PMID:26896539

  9. Genomic organization of the human thyroid hormone receptor alpha (c-erbA-1) gene.

    Laudet, V; Begue, A; Henry-Duthoit, C; Joubel, A; P. Martin; Stehelin, D.; Saule, S.


    The thyroid hormone receptor alpha (THRA or c-erbA-1) gene belongs to a family of genes which encode nuclear receptors for various hydrophobic ligands such as steroids, vitamin D, retinoic acid and thyroid hormones. These receptors are composed of several domains important for hormone-binding, DNA-binding, dimerization and activation of transcription. We show here that the human THRA gene is organized in 10 exons distributed along 27 kbp of genomic DNA on chromosome 17. The position of the in...

  10. Alien, a Highly Conserved Protein with Characteristics of a Corepressor for Members of the Nuclear Hormone Receptor Superfamily

    Dressel, Uwe; Thormeyer, Dorit; Altincicek, Boran; Paululat, Achim; Eggert, Martin; Schneider, Sandra; Tenbaum, Stephan P.; Renkawitz, Rainer; Baniahmad, Aria


    Some members of nuclear hormone receptors, such as the thyroid hormone receptor (TR), silence gene expression in the absence of the hormone. Corepressors, which bind to the receptor’s silencing domain, are involved in this repression. Hormone binding leads to dissociation of corepressors and binding of coactivators, which in turn mediate gene activation. Here, we describe the characteristics of Alien, a novel corepressor. Alien interacts with TR only in the absence of hormone. Addition of thy...

  11. Impaired hair growth and wound healing in mice lacking thyroid hormone receptors

    Contreras-Jurado, Constanza; García-Serrano, Laura; Martínez-Fernández, Mónica; Ruiz-Llorente, Lidia; Paramio, Jesús M.; Aranda, Ana


    Both clinical and experimental observations show that the skin is affected by the thyroidal status. In hypothyroid patients the epidermis is thin and alopecia is common, indicating that thyroidal status might influence not only skin proliferation but also hair growth. We demonstrate here that the thyroid hormone receptors (TRs) mediate these effects of the thyroid hormones on the skin. Mice lacking TRα1 and TRβ (the main thyroid hormone binding isoforms) display impaired hair cycling associat...

  12. Analysis of the hormone-binding domain of steroid receptors using chimeras generated by homologous recombination

    The glucocorticoid receptor and the mineralocorticoid receptor are members of the steroid receptor family that exhibit ligand cross-reactivity. Specificity of steroid receptor action is investigated in the present work by the construction and characterization of chimeras between the glucocorticoid receptor and the mineralocorticoid receptor. We used an innovative approach to make novel steroid receptor proteins in vivo that in general, contrary to our expectations, show increased ligand specificity compared to the parental receptors. We describe a receptor that is specific for the potent synthetic glucocorticoid triamcinolone acetonide and does not bind aldosterone. A further set of chimeras has an increased ability to discriminate between ligands, responding potently to mineralocorticoids and only very weakly to synthetic glucocorticoids. A chimera with the fusion site in the hinge highlights the importance of the region between the DNA-binding and the hormone-binding domains since, unlike both the glucocorticoid and mineralocorticoid receptors, it only responds to mineralocorticoids. One chimera has reduced specificity in that it acts as a general corticoid receptor, responding to glucocorticoids and mineralocorticoids with similar potency and efficacy. Our data suggest that regions of the glucocorticoid and mineralocorticoid receptor hormone-binding domains are functionally non-reciprocal. We present transcriptional, hormone-binding, and structure-modeling evidence that suggests that receptor-specific interactions within and across domains mediate aspects of specificity in transcriptional responses to steroids

  13. Detection of thyroid hormone receptor disruptors by a novel stable in vitro reporter gene assay

    Freitas, de J.; Cano, P.; Craig-Veit, C.; Goodson, M.L.; Furlow, J.D.; Murk, A.J.


    A stable luciferase reporter gene assay was developed based on the thyroid hormone responsive rat pituitary tumor GH3 cell line that constitutively expresses both thyroid hormone receptor isoforms. Stable transfection of the pGL4CP-SV40-2xtaDR4 construct into the GH3 cells resulted in a highly sensi

  14. Molecular cloning and functional characterization of the diapause hormone receptor in the corn earworm Helicoverpa zea

    The diapause hormone (DH) in the heliothine moth has shown its activity in termination of pupal diapause, while the orthology in the silkworm is known to induce embryonic diapause. In the current study, we cloned the diapause hormone receptor from the corn earworm Helicoverpa zea (HzDHr) and tested ...

  15. Expression of Growth Hormone Receptors by Lymphocyte subpopulations in the Human tonsil

    Olivier Thellin; Bernard Coumans; Willy Zorzi; Ross Barnard; Georges Hennen; Ernst Heinen; Ahmed Igout


    The ability of human tonsillar lymphoid cells to express growth hormone receptor (hGH-N-R) was analyzed by flow cytometry. FITC-coupled recombinant human growth hormone (hGH-N) was used to reveal the receptors, in combination with phenotype markers. Unlike T cells, tonsillar B cells constitutively express the hGH-N receptor. Quiescent cells separated from activated cells by Percoll-gradient centrifugation bear fewer receptors than activated ones. Activated T cells express hGH-N-R, but the typ...

  16. (−) Arctigenin and (+) Pinoresinol Are Antagonists of the Human Thyroid Hormone Receptor β


    Lignans are important biologically active dietary polyphenolic compounds. Consumption of foods that are rich in lignans is associated with positive health effects. Using modeling tools to probe the ligand-binding pockets of molecular receptors, we found that lignans have high docking affinity for the human thyroid hormone receptor β. Follow-up experimental results show that lignans (−) arctigenin and (+) pinoresinol are antagonists of the human thyroid hormone receptor β. The modeled complexes show key plausible interactions between the two ligands and important amino acid residues of the receptor. PMID:25383984

  17. (-) Arctigenin and (+) pinoresinol are antagonists of the human thyroid hormone receptor β.

    Ogungbe, Ifedayo Victor; Crouch, Rebecca A; Demeritte, Teresa


    Lignans are important biologically active dietary polyphenolic compounds. Consumption of foods that are rich in lignans is associated with positive health effects. Using modeling tools to probe the ligand-binding pockets of molecular receptors, we found that lignans have high docking affinity for the human thyroid hormone receptor β. Follow-up experimental results show that lignans (-) arctigenin and (+) pinoresinol are antagonists of the human thyroid hormone receptor β. The modeled complexes show key plausible interactions between the two ligands and important amino acid residues of the receptor. PMID:25383984

  18. Short-term outcome of primary operated early breast cancer by hormone and HER-2 receptors


    Abstract Introduction Prognostic subgroup classification of operable breast cancers using cDNA clustering of breast cancer-related genes resembles the classification based on the combined immunohistochemical (IHC) expression of the hormone and HER-2 receptors. We here report the short-term disease-free interval (DFI) of operable breast cancers by their joint hormone receptor/HER-2 phenotype. Patients and methods Short-term follow-up (FU) of ...


    Nigel Bennett; Retnagowri Rajandram; Keng Lim Ng; Gobe, Glenda C


    Steroid hormones and their receptors have important roles in normal kidney biology, and alterations in their expression and function help explain the differences in development of kidney diseases, such as nephrotic syndrome and chronic kidney disease. The distinct gender difference in incidence of renal cell carcinoma (RCC), with males having almost twice the incidence as females globally, also suggests a role for sex hormones or their receptors in RCC development and progression. There was a...

  20. Proteolytic activity of the purified hormone-binding subunit in the estrogen receptor.

    Molinari, A M; Abbondanza, C; Armetta, I.; Medici, N; Minucci, S; Moncharmont, B; Nigro, V; Puca, G A


    The hormone-binding subunit of the calf uterus estradiol receptor was purified as a hormone-free molecule. Immunoaffinity chromatography with a specific monoclonal antibody was used as the final step. The purified subunit was specifically labeled by radioactive diisopropyl fluorophosphate. The diisopropyl fluorophosphate-labeled amino acid was serine. The purified receptor was able to release the fluorogenic or chromogenic group from synthetic peptides containing phenylalanine at the carboxyl...

  1. Amphioxus: beginning of vertebrate and end of invertebrate type GnRH receptor lineage.

    Tello, Javier A; Sherwood, Nancy M


    In vertebrates, activation of the GnRH receptor is necessary to initiate the reproductive cascade. However, little is known about the characteristics of GnRH receptors before the vertebrates evolved. Recently genome sequencing was completed for amphioxus, Branchiostoma floridae. To understand the GnRH receptors (GnRHR) from this most basal chordate, which is also classified as an invertebrate, we cloned and characterized four GnRHR cDNAs encoded in the amphioxus genome. We found that incubation of GnRH1 (mammalian GnRH) and GnRH2 (chicken GnRH II) with COS7 cells heterologously expressing the amphioxus GnRHRs caused potent intracellular inositol phosphate turnover in two of the receptors. One of the two receptors displayed a clear preference for GnRH1 over GnRH2, a characteristic not previously seen outside the type I mammalian GnRHRs. Phylogenetic analysis grouped the four receptors into two paralogous pairs, with one pair grouping basally with the vertebrate GnRH receptors and the other grouping with the octopus GnRHR-like sequence and the related receptor for insect adipokinetic hormone. Pharmacological studies showed that octopus GnRH-like peptide and adipokinetic hormone induced potent inositol phosphate turnover in one of these other two amphioxus receptors. These data demonstrate the functional conservation of two distinct types of GnRH receptors at the base of chordates. We propose that one receptor type led to vertebrate GnRHRs, whereas the other type, related to the mollusk GnRHR-like receptor, was lost in the vertebrate lineage. This is the first report to suggest that distinct invertebrate and vertebrate GnRHRs are present simultaneously in a basal chordate, amphioxus. PMID:19264870

  2. Signaling by Tyrosine Kinases Negatively Regulates the Interaction between Transcription Factors and SMRT (Silencing Mediator of Retinoic Acid and Thyroid Hormone Receptor) Corepressor

    Hong, Suk-Hyun; Wong, Chi-Wai; Privalsky, Martin L.


    Nuclear hormone receptors are hormone-regulated transcription factors that bind to specific sites on DNA and modulate the expression of adjacent target genes. Many nuclear hormone receptors display bimodal transcriptional properties; thyroid hormone receptors, for example, typically repress target gene expression in the absence of hormone, but activate target gene expression in the presence of hormone. The ability to repress is closely linked to the ability of the apo-receptor to physically b...

  3. Bioluminescent Ligand-Receptor Binding Assays for Protein or Peptide Hormones.

    Liu, Ya-Li; Guo, Zhan-Yun


    Bioluminescence has been widely used in biomedical research due to its high sensitivity, low background, and broad linear range. In recent studies, we applied bioluminescence to ligand-receptor binding assays for some protein or peptide hormones based on a newly developed small monomeric Nanoluciferase (NanoLuc) reporter that has the so far brightest bioluminescence. The conventional ligand-receptor binding assays rely on radioligands that have drawbacks, such as radioactive hazards and short shelf lives. In contrast, the novel bioluminescent binding assays use the NanoLuc-based protein or peptide tracers that are safe, stable, and ultrasensitive. Thus, the novel bioluminescent ligand-receptor binding assay would be applied to more and more protein or peptide hormones for ligand-receptor interaction studies in future. In the present article, we provided detailed protocols for setting up the novel bioluminescent ligand-receptor binding assays using two representative protein hormones as examples. PMID:27424896

  4. Localization and synthesis of the hormone-binding regions of the human thyrotropin receptor.

    Atassi, M Z; Manshouri, T; Sakata, S.


    Two regions of human thyrotropin (thyroid-stimulating hormone, TSH) receptor (TSHR) (residues 12-44 and 308-364) were selected on the basis that they exhibit no sequence resemblance to luteinizing hormone/chorionic gonadotropin receptor. Five synthetic overlapping peptides (12-30, 24-44, 308-328, 324-344, and 339-364) were studied for their ability to bind 125I-labeled human TSH (hTSH), its isolated alpha and beta subunits, bovine TSH, ovine TSH, human luteinizing hormone, and human follicle-...

  5. Luteinizing hormone-releasing hormone receptor-mediated delivery of mitoxantrone using LHRH analogs modified with PEGylated liposomes

    Yingna He


    Full Text Available Yingna He, Linhua Zhang, Cunxian SongKey Laboratory of Biomedical Material of Tianjin, Institute of Biomedical Engineering, Peking Union Medical College and Chinese Academy of Medical Sciences, Tianjin, ChinaAbstract: A sterically stabilized, mitoxantrone-loaded liposome, tailored to target luteinizing hormone-releasing hormone (LHRH receptor overexpressing cells, was developed to promote the efficiency of intracellular delivery of mitoxantrone through receptor-mediated endocytosis. Liposomes were prepared by lipid film hydration and an ultrasound dispersion process. Thiolated gonadorelin with affinity for the LHRH receptor was chemically coupled to N-[(3-maleimide-1-oxopropyl aminopropyl polyethylene glycol-carbamyl] distearoyl-l-phosphatidyl-ethanolamine via a thioether bond and subsequently inserted into polyethylene glycol-grafted liposomes. The liposome was characterized in terms of its size, ligand density, drug loading, and leakage properties. The targeting nature and antitumor effects of the liposomes were evaluated in vitro using cultured MCF-7 breast cancer cells. A protein assay of ligand coupling to the liposomal surface indicated that more than 60% of the LHRH peptides were inserted into the liposome bilayer. Up to 1.0 mg/mL of stable liposomal mitoxantrone loading was achieved, with approximately 98% of this being entrapped within the liposomes. In vitro cell culture studies revealed that the gonadorelin-modified liposomes bound to their target cells had significantly higher affinity and better antitumor efficiency than generic drug-loaded liposomes. These events were presumed to occur through specific interactions of the LHRH with its cognate receptors on the cell surface. It was concluded that the targeting properties of the delivery system would potentially improve the therapeutic benefits of mitoxantrone, as compared with nontargeted liposomes.Keywords: mitoxantrone, liposome, luteinizing hormone-releasing hormone receptor

  6. Pentadecapeptide BPC 157 Enhances the Growth Hormone Receptor Expression in Tendon Fibroblasts

    Chung-Hsun Chang


    Full Text Available BPC 157, a pentadecapeptide derived from human gastric juice, has been demonstrated to promote the healing of different tissues, including skin, muscle, bone, ligament and tendon in many animal studies. However, the underlying mechanism has not been fully clarified. The present study aimed to explore the effect of BPC 157 on tendon fibroblasts isolated from Achilles tendon of male Sprague-Dawley rat. From the result of cDNA microarray analysis, growth hormone receptor was revealed as one of the most abundantly up-regulated genes in tendon fibroblasts by BPC 157. BPC 157 dose- and time-dependently increased the expression of growth hormone receptor in tendon fibroblasts at both the mRNA and protein levels as measured by RT/real-time PCR and Western blot, respectively. The addition of growth hormone to BPC 157-treated tendon fibroblasts dose- and time-dependently increased the cell proliferation as determined by MTT assay and PCNA expression by RT/real-time PCR. Janus kinase 2, the downstream signal pathway of growth hormone receptor, was activated time-dependently by stimulating the BPC 157-treated tendon fibroblasts with growth hormone. In conclusion, the BPC 157-induced increase of growth hormone receptor in tendon fibroblasts may potentiate the proliferation-promoting effect of growth hormone and contribute to the healing of tendon.

  7. Steroid hormone receptors in prostatic hyperplasia and prostatic carcinoma.

    Khalid, B A; Nurshireen, A; Rashidah, M; Zainal, B Y; Roslan, B A; Mahamooth, Z


    One hundred and six prostatic tissue samples obtained from transurethral resection were analysed for androgen and estrogen receptors. In 62 of these, progesterone and glucocorticoid receptors were also assayed. Steroid receptors were assayed using single saturation dose 3H-labelled ligand assays. Ninety percent of the 97 prostatic hyperplasia tissues and six of the nine prostatic carcinoma tissues were positive for androgen receptors. Estrogen receptors were only present in 19% and 33% respectively. Progesterone receptors were present in 70% of the tissues, but glucocorticoid receptors were present in only 16% of prostatic hyperplasia and none in prostatic carcinoma. PMID:1725553

  8. Growth hormone promoted tyrosyl phosphorylation of growth hormone receptors in murine 3T3-F442A fibroblasts and adipocytes

    Foster, C.M.; Shafer, J.A.; Rozsa, F.W.; Wang, X.; Lewis, S.D.; Renken, D.A.; Natale, J.E.; Schwartz, J.; Carter-Su, C.


    Because many growth factor receptors are ligand-activated tyrosine protein kinases, the possibility that growth hormone (GH), a hormone implicated in human growth, promotes tyrosyl phosphorylation of its receptor was investigated. /sup 125/I-Labeled human GH was covalently cross-linked to receptors in intact 3T3-F442A fibroblasts, a cell line which differentiates into adipocytes in response to GH. The cross-linked cells were solubilized and passed over a column of phosphotyrosyl binding antibody immobilized on protein A-Sepharose. Immunoadsorbed proteins were eluted with a hapten (p-nitrophenyl phosphate) and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. The eluate from the antibody column contained in M/sub r/ 134,000 /sup 125/I-GH-receptor complex. A similar result was obtained when the adipocyte form of 3T3-F442A cells was used in place of fibroblast form. O-Phosphotyrosine prevented /sup 125/I-GH-receptor complexes from binding to the antibody column, whereas O-phosphoserine and O-phosphothreonine did not. In studies of GH-promoted phosphorylation in 3T3-F442A fibroblasts labeled metabolically with (/sup 32/P)P/sub i/, GH was shown to stimulate formation of a /sup 32/P-labeled protein which bound to immobilized phosphotyrosyl binding antibodies. The molecular weight of 114,000 obtained for this protein is similar to that expected for non-cross-linked GH receptor. These observations provide strong evidence that binding of GH to its receptor stimulates phosphorylation of tyrosyl residues in the GH receptor.

  9. Growth hormone promoted tyrosyl phosphorylation of growth hormone receptors in murine 3T3-F442A fibroblasts and adipocytes

    Because many growth factor receptors are ligand-activated tyrosine protein kinases, the possibility that growth hormone (GH), a hormone implicated in human growth, promotes tyrosyl phosphorylation of its receptor was investigated. 125I-Labeled human GH was covalently cross-linked to receptors in intact 3T3-F442A fibroblasts, a cell line which differentiates into adipocytes in response to GH. The cross-linked cells were solubilized and passed over a column of phosphotyrosyl binding antibody immobilized on protein A-Sepharose. Immunoadsorbed proteins were eluted with a hapten (p-nitrophenyl phosphate) and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. The eluate from the antibody column contained in M/sub r/ 134,000 125I-GH-receptor complex. A similar result was obtained when the adipocyte form of 3T3-F442A cells was used in place of fibroblast form. O-Phosphotyrosine prevented 125I-GH-receptor complexes from binding to the antibody column, whereas O-phosphoserine and O-phosphothreonine did not. In studies of GH-promoted phosphorylation in 3T3-F442A fibroblasts labeled metabolically with [32P]P/sub i/, GH was shown to stimulate formation of a 32P-labeled protein which bound to immobilized phosphotyrosyl binding antibodies. The molecular weight of 114,000 obtained for this protein is similar to that expected for non-cross-linked GH receptor. These observations provide strong evidence that binding of GH to its receptor stimulates phosphorylation of tyrosyl residues in the GH receptor

  10. Characterization of the ligand-dependent transactivation domain of thyroid hormone receptor.

    Barettino, D; Vivanco Ruiz, M M; Stunnenberg, H.G.


    Transcriptional activation by nuclear receptors is achieved through autonomous activation functions (AFs), a constitutive N-terminal AF-1 and a C-terminal, ligand-dependent AF-2 that comprises a motif conserved between nuclear receptors. We have performed an extensive mutational analysis of the putative AF-2 domain of chicken thyroid hormone receptor alpha (cT3R alpha). We show that the AF-2 region mediates transactivation as well as transcriptional interference (squelching), not only between...

  11. Hormone-receptor expression and ovarian cancer survival

    Sieh, Weiva; Köbel, Martin; Longacre, Teri A;


    Few biomarkers of ovarian cancer prognosis have been established, partly because subtype-specific associations might be obscured in studies combining all histopathological subtypes. We examined whether tumour expression of the progesterone receptor (PR) and oestrogen receptor (ER) was associated ...

  12. Impaired hair growth and wound healing in mice lacking thyroid hormone receptors.

    Constanza Contreras-Jurado

    Full Text Available Both clinical and experimental observations show that the skin is affected by the thyroidal status. In hypothyroid patients the epidermis is thin and alopecia is common, indicating that thyroidal status might influence not only skin proliferation but also hair growth. We demonstrate here that the thyroid hormone receptors (TRs mediate these effects of the thyroid hormones on the skin. Mice lacking TRα1 and TRβ (the main thyroid hormone binding isoforms display impaired hair cycling associated to a decrease in follicular hair cell proliferation. This was also observed in hypothyroid mice, indicating the important role of the hormone-bound receptors in hair growth. In contrast, the individual deletion of either TRα1 or TRβ did not impair hair cycling, revealing an overlapping or compensatory role of the receptors in follicular cell proliferation. In support of the role of the receptors in hair growth, TRα1/TRβ-deficient mice developed alopecia after serial depilation. These mice also presented a wound-healing defect, with retarded re-epithelialization and wound gaping, associated to impaired keratinocyte proliferation. These results reinforce the idea that the thyroid hormone nuclear receptors play an important role on skin homeostasis and suggest that they could be targets for the treatment of cutaneous pathologies.

  13. Novel bioluminescent binding assays for interaction studies of protein/peptide hormones with their receptors.

    Liu, Ya-Li; Guo, Zhan-Yun


    Protein/peptide hormones are the largest group of endogenous signaling molecules and exert various biological functions by binding to specific cell membrane receptors. To study the interactions between these hormones and their receptors, quantitative ligand-receptor binding assays have been widely used for decades. However, the assays conventionally relied on the use of radioligands, which have some major drawbacks and can only be used in laboratories with a radioactive material license. We recently developed novel bioluminescent binding assays for several protein/peptide hormones using the brightest bioluminescent reporter known to date, nanoluciferase (NanoLuc). The NanoLuc reporter can be either chemically conjugated to an appropriate position, or genetically fused at one terminus, of protein/peptide hormones. Compared to conventional radioligands, these bioluminescent ligands have higher sensitivity, better safety, and longer shelf lives, and thus, represent a novel class of non-radioactive tracers for quantitative receptor binding assays. In the present review, we provide some general considerations and specific examples for setting up the bioluminescent binding assays. Such techniques can be applied to other protein/peptide hormones in future to facilitate their interaction studies with their receptors. PMID:27020777

  14. Introduction of exogenous growth hormone receptors augments growth hormone-responsive insulin biosynthesis in rat insulinoma cells

    The stimulation of insulin biosynthesis in the pancreatic insulinoma cell line RIN5-AH by growth hormone (GH) is initiated by GH binding to specific receptors. To determine whether the recently cloned rat hepatic GH receptor is able to mediate the insulinotropic effect of GH, the authors have transfected a GH receptor cDNA under the transcriptional control of the human metallothionein promoter into RIN5-AH cells. The transfected cells were found to exhibit an increased expression of GH receptors and to contain a specific GH receptor mRNA that was not expressed in the parent cell line. The expression of GH receptors in one clone (1.24) selected for detailed analysis was increased 2.6-fold compared to untransfected cells. The increased GH receptor expression was accompanied by an increased responsiveness to GH. Thus, the maximal GH-stimulated increase of insulin biosynthesis was 4.1-fold in 1.24 cells compared to 1.9-fold in the nontransfected RIN5-AH cells. The expression of the transfected receptor was stimulated 1.6- and 2.3-fold when cells were cultured in the presence of 25 or 50 μM Zn2+ was associated with an increased magnitude of GH-stimulated insulin biosynthesis. A close stoichiometric relationship between the level of receptor expression and the level of GH-stimulated insulin biosynthesis was observed. They conclude from these results that the hepatic GH receptor is able to mediate the effect of GH on insulin biosynthesis in RIN5-AH cells

  15. Distinct RNA motifs are important for coactivation of steroid hormone receptors by steroid receptor RNA activator (SRA)

    Lanz, Rainer B.; Razani, Bahram; Goldberg, Aaron D.; O'Malley, Bert W.


    Steroid receptor RNA activator (SRA) is an RNA transcript that functions as a eukaryotic transcriptional coactivator for steroid hormone receptors. We report here the isolation and functional characterization of distinct RNA substructures within the SRA molecule that constitute its coactivation function. We used comparative sequence analysis and free energy calculations to systematically study SRA RNA subdomains for identification of structured regions and base pairings, and we used site-dire...

  16. Hormones

    Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. They work ... glands, which are special groups of cells, make hormones. The major endocrine glands are the pituitary, pineal, ...

  17. The role of melanin-concentrating hormone and its receptors in energy homeostasis



    Extensive studies in rodents with melanin-concentrating hormone (MCH) have demonstrated that the neuropeptide hormone is a potent orexigen. Acutely, MCH causes an increase in food intake, while chronically it leads to increased weight gain, primarily as an increase in fat mass. Multiple knockout mice models have confirmed the importance of MCH in modulating energy homeostasis. Animals lacking MCH, MCH-containing neurons, or the MCH receptor all are resistant to diet-induced obesity. These gen...

  18. Complex Actions of Thyroid Hormone Receptor Antagonist NH-3 on Gene Promoters in Different Cell Lines

    Shah, Vanya; Nguyen, Van Phuong; Nguyen, Ngoc-Ha; Togashi, Marie; Scanlan, Thomas S.; Baxter, John D.; Webb, Paul


    It is desirable to obtain new antagonists for thyroid hormone (TRs) and other nuclear receptors (NRs). We previously used X-ray structural models of TR ligand binding domains (LBDs) to design compounds, such as NH-3, that impair coactivator binding to activation function 2 (AF-2) and block thyroid hormone (triiodothyronine, T3) actions. However, TRs bind DNA and are transcriptionally active without ligand. Thus, NH-3 could modulate TR activity via effects on other coregulator interaction surf...

  19. Identification and optimization of small-molecule agonists of the human relaxin hormone receptor RXFP1

    Xiao, Jingbo; Huang, Zaohua; Chen, Catherine Z.; Agoulnik, Irina U; Southall, Noel; Hu, Xin; Jones, Raisa E.; Ferrer, Marc; Zheng, Wei; Agoulnik, Alexander I.; Marugan, Juan J


    The anti-fibrotic, vasodilatory, and pro-angiogenic therapeutic properties of recombinant relaxin peptide hormone have been investigated in several diseases and recent clinical trial data has shown benefit in treating acute heart failure. However, the remodeling capacity of these peptide hormones is difficult to study in chronic settings due to their short half-life and the need for intravenous administration. Here we present the first small-molecule series of human relaxin receptor 1 (RXFP1)...

  20. The glucocorticoid receptor hormone binding domain mediates transcriptional activation in vitro in the absence of ligand.

    Schmitt, J.; Stunnenberg, H G


    We show that recombinant rat glucocorticoid receptor (vvGR) expressed using vaccinia virus is indistinguishable from authentic GR with respect to DNA and hormone binding. In the absence of hormone, vvGR is mainly found in the cytoplasm in a complex with heat shock protein 90. Upon incubation with ligand, vvGR is released from this complex and translocated to the nucleus. Thus, the ligand binding domain displays the known biochemical properties. However, in vitro, transcription from a syntheti...

  1. Analysis of Paired Primary-Metastatic Hormone-Receptor Positive Breast Tumors (HRPBC Uncovers Potential Novel Drivers of Hormonal Resistance.

    Luis Manso

    Full Text Available We sought to identify genetic variants associated with disease relapse and failure to hormonal treatment in hormone-receptor positive breast cancer (HRPBC. We analyzed a series of HRPBC with distant relapse, by sequencing pairs (n = 11 of tumors (primary and metastases at >800X. Comparative genomic hybridization was performed as well. Top hits, based on the frequency of alteration and severity of the changes, were tested in the TCGA series. Genes determining the most parsimonious prognostic signature were studied for their functional role in vitro, by performing cell growth assays in hormonal-deprivation conditions, a setting that mimics treatment with aromatase inhibitors. Severe alterations were recurrently found in 18 genes in the pairs. However, only MYC, DNAH5, CSFR1, EPHA7, ARID1B, and KMT2C preserved an independent prognosis impact and/or showed a significantly different incidence of alterations between relapsed and non-relapsed cases in the TCGA series. The signature composed of MYC, KMT2C, and EPHA7 best discriminated the clinical course, (overall survival 90,7 vs. 144,5 months; p = 0.0001. Having an alteration in any of the genes of the signature implied a hazard ratio of death of 3.25 (p<0.0001, and early relapse during the adjuvant hormonal treatment. The presence of the D348N mutation in KMT2C and/or the T666I mutation in the kinase domain of EPHA7 conferred hormonal resistance in vitro. Novel inactivating mutations in KMT2C and EPHA7, which confer hormonal resistance, are linked to adverse clinical course in HRPBC.

  2. Analysis of Paired Primary-Metastatic Hormone-Receptor Positive Breast Tumors (HRPBC) Uncovers Potential Novel Drivers of Hormonal Resistance.

    Manso, Luis; Mourón, Silvana; Tress, Michael; Gómez-López, Gonzalo; Morente, Manuel; Ciruelos, Eva; Rubio-Camarillo, Miriam; Rodriguez-Peralto, Jose Luis; Pujana, Miguel A; Pisano, David G; Quintela-Fandino, Miguel


    We sought to identify genetic variants associated with disease relapse and failure to hormonal treatment in hormone-receptor positive breast cancer (HRPBC). We analyzed a series of HRPBC with distant relapse, by sequencing pairs (n = 11) of tumors (primary and metastases) at >800X. Comparative genomic hybridization was performed as well. Top hits, based on the frequency of alteration and severity of the changes, were tested in the TCGA series. Genes determining the most parsimonious prognostic signature were studied for their functional role in vitro, by performing cell growth assays in hormonal-deprivation conditions, a setting that mimics treatment with aromatase inhibitors. Severe alterations were recurrently found in 18 genes in the pairs. However, only MYC, DNAH5, CSFR1, EPHA7, ARID1B, and KMT2C preserved an independent prognosis impact and/or showed a significantly different incidence of alterations between relapsed and non-relapsed cases in the TCGA series. The signature composed of MYC, KMT2C, and EPHA7 best discriminated the clinical course, (overall survival 90,7 vs. 144,5 months; p = 0.0001). Having an alteration in any of the genes of the signature implied a hazard ratio of death of 3.25 (p<0.0001), and early relapse during the adjuvant hormonal treatment. The presence of the D348N mutation in KMT2C and/or the T666I mutation in the kinase domain of EPHA7 conferred hormonal resistance in vitro. Novel inactivating mutations in KMT2C and EPHA7, which confer hormonal resistance, are linked to adverse clinical course in HRPBC. PMID:27195705

  3. Presence of a putative steroidal allosteric site on glycoprotein hormone receptors.

    Rossi, Mario; Dimida, Antonio; Ferrarini, Eleonora; Silvano, Elena; De Marco, Giuseppina; Agretti, Patrizia; Aloisi, Gabriella; Simoncini, Tommaso; Di Bari, Lorenzo; Tonacchera, Massimo; Giorgi, Franco; Maggio, Roberto


    In a previous work we found that the insecticide 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), inhibits the accumulation of cAMP as induced by the bovine thyroid stimulating hormone (bTSH) in cells transfected with the TSH receptor. In this work, we demonstrate that the DDT molecular analogues, diethylstilbestrol and quercetine, are more potent inhibitors of the TSH receptor activity than DDT itself. The notion that all these compounds interfere with nuclear estrogen receptors, as either agonists (DDT and diethylstilbestrol) or antagonists (quercetin), prompted us to test the ability of the steroid hormone 17-beta-estradiol to inhibit the TSH receptor activity. We found that estrogen exposure causes a modest but significant inhibition of the bTSH induced cAMP accumulation both in transfected CHO-TSH receptor and Fischer Rat Thyroid Low Serum 5% (FRTL-5) cells. When applied to CHO cells transfected with the luteinizing hormone receptor, 17-beta-estradiol proved capable of inhibiting the hCG induced cAMP accumulation at a concentration as low as 10nM, though the effect was not greater than 35%. The effect of 17-beta-estradiol was not estrogen receptors mediated, as co-transfection of the estrogen receptor alpha and beta subunits with LH receptor caused cAMP to increase above the level attained by the sole hCG stimulation, and not to decrease it as expected. These data suggest the presence of a steroidal-like allosteric binding site on glycoprotein hormone receptors. PMID:19766106

  4. Identification and optimization of small-molecule agonists of the human relaxin hormone receptor RXFP1.

    Xiao, Jingbo; Huang, Zaohua; Chen, Catherine Z; Agoulnik, Irina U; Southall, Noel; Hu, Xin; Jones, Raisa E; Ferrer, Marc; Zheng, Wei; Agoulnik, Alexander I; Marugan, Juan J


    The anti-fibrotic, vasodilatory and pro-angiogenic therapeutic properties of recombinant relaxin peptide hormone have been investigated in several diseases, and recent clinical trial data has shown benefit in treating acute heart failure. However, the remodelling capacity of these peptide hormones is difficult to study in chronic settings because of their short half-life and the need for intravenous administration. Here we present the first small-molecule series of human relaxin/insulin-like family peptide receptor 1 agonists. These molecules display similar efficacy as the natural hormone in several functional assays. Mutagenesis studies indicate that the small molecules activate relaxin receptor through an allosteric site. These compounds have excellent physical and in vivo pharmacokinetic properties to support further investigation of relaxin biology and animal efficacy studies of the therapeutic benefits of relaxin/insulin-like family peptide receptor 1 activation. PMID:23764525

  5. Proteolytic activity of the purified hormone-binding subunit in the estrogen receptor.

    Molinari, A M; Abbondanza, C; Armetta, I; Medici, N; Minucci, S; Moncharmont, B; Nigro, V; Puca, G A


    The hormone-binding subunit of the calf uterus estradiol receptor was purified as a hormone-free molecule. Immunoaffinity chromatography with a specific monoclonal antibody was used as the final step. The purified subunit was specifically labeled by radioactive diisopropyl fluorophosphate. The diisopropyl fluorophosphate-labeled amino acid was serine. The purified receptor was able to release the fluorogenic or chromogenic group from synthetic peptides containing phenylalanine at the carboxyl terminus. This occurred only in the presence of estradiol and was hampered by aprotinin and diisopropyl fluorophosphate. Estradiol-dependent hydrolytic activity was also found in the eluate from gel slices after SDS/PAGE of purified receptor. This activity comigrated with the renaturable estradiol-binding activity. The estradiol antagonists 4-hydroxytamoxifen and ICI 164,384 as well as other steroid hormones were unable to activate this hydrolytic activity. PMID:1709742

  6. In silico modelling of prostacyclin and other lipid mediators to nuclear receptors reveal novel thyroid hormone receptor antagonist properties.

    Perez Diaz, Noelia; Zloh, Mire; Patel, Pryank; Mackenzie, Louise S


    Prostacyclin (PGI2) is a key mediator involved in cardiovascular homeostasis, acting predominantly on two receptor types; cell surface IP receptor and cytosolic peroxisome proliferator activated receptor (PPAR) β/δ. Having a very short half-life, direct methods to determine its long term effects on cells is difficult, and little is known of its interactions with nuclear receptors. Here we used computational chemistry methods to investigate the potential for PGI2, beraprost (IP receptor agonist), and GW0742 (PPARβ/δ agonist), to bind to nuclear receptors, confirmed with pharmacological methods. In silico screening predicted that PGI2, beraprost, and GW0742 have the potential to bind to different nuclear receptors, in particular thyroid hormone β receptor (TRβ) and thyroid hormone α receptor (TRα). Docking analysis predicts a binding profile to residues thought to have allosteric control on the TR ligand binding site. Luciferase reporter assays confirmed that beraprost and GW0742 display TRβ and TRα antagonistic properties; beraprost IC50 6.3×10(-5)mol/L and GW0742 IC50 4.9×10(-6)mol/L. Changes to triiodothyronine (T3) induced vasodilation of rat mesenteric arteries measured on the wire myograph were measured in the presence of the TR antagonist MLS000389544 (10(-5)mol/L), beraprost (10(-5)mol/L) and GW0742 (10(-5)mol/L); all significantly inhibited T3 induced vasodilation compared to controls. We have shown that both beraprost and GW0742 exhibit TRβ and TRα antagonist behaviour, and suggests that PGI2 has the ability to affect the long term function of cells through binding to and inactivating thyroid hormone receptors. PMID:26686607

  7. Association of the thyroid stimulating hormone receptor gene (TSHR) with Graves' disease

    Brand, Oliver J; Barrett, Jeffrey C; Simmonds, Matthew J;


    Graves' disease (GD) is a common autoimmune disease (AID) that shares many of its susceptibility loci with other AIDs. The thyroid stimulating hormone receptor (TSHR) represents the primary autoantigen in GD, in which autoantibodies bind to the receptor and mimic its ligand, thyroid stimulating...... hormone, causing the characteristic clinical phenotype. Although early studies investigating the TSHR and GD proved inconclusive, more recently we provided convincing evidence for association of the TSHR region with disease. In the current study, we investigated a combined panel of 98 SNPs, including 70...

  8. Estrogen receptor isoforms and progestin hormone dependence in a mouse mammary tumor model.

    Actis, A M; Caruso, S P; Levin, E


    The close interaction between receptors and other transcription factors suggests that their corresponding transducing signals can trigger functional and structural changes in other related molecules. The effect of a progestinic agent, medroxyprogesterone acetate (MPA), on some of the estrogen-receptor (ER) parameters was studied in 2 murine mammary tumor sublines with different progestin hormone dependence for their respective growth. The relative binding affinity of estradiol and tamoxifen for the ER, the receptor content and the ER isoforms studied by HPLC were determined in the hormone-autonomous (HA) and the hormone-dependent (HD) tumor sublines. In the HA subline administration of MPA did not modify the tumor growth rate, whereas this was accelerated in the HD subline. The ER content was clearly increased in the HD tumor subline, but not in the HA subline, compared with the untreated controls. In contrast, the E2 and tamoxifen relative binding affinity for the ER and the isoform profiles were affected by MPA treatment in the HA, but not in the HD tumor subline. The functional change (decrease in relative binding affinity) can be attributed to the appearance of a lower-molecular-size ER isoform under the progestinic treatment. Modifications in one receptor molecule by the action of ligands corresponding to another type of receptor show the interconection between transcription factors and the necessity of broadening conventional concepts regarding hormone dependence in mammary tumorigenesis. PMID:8077051


    Nigel Bennett


    Full Text Available Steroid hormones and their receptors have important roles in normal kidney biology, and alterations in their expression and function help explain the differences in development of kidney diseases, such as nephrotic syndrome and chronic kidney disease. The distinct gender difference in incidence of renal cell carcinoma (RCC, with males having almost twice the incidence as females globally, also suggests a role for sex hormones or their receptors in RCC development and progression. There was a peak in interest in evaluating the roles of androgen and estrogen receptors in RCC pathogenesis in the late 20th century, with some positive outcomes for RCC therapy that targeted estrogen receptors, especially for metastatic disease. Since that time, however, there have been few studies that look at use of steroid hormone modulators for RCC, especially in the light of new therapies such as the tyrosine kinase inhibitors and new immune therapies, which are having some success for treatment of metastatic RCC. This review summarises past and current literature and attempts to stimulate renewed interest in research into the steroid hormones and their receptors, which might be used to effect, for example, in combination with the other newer targeted therapies for RCC.

  10. Growth Hormone (GH1) Gene Variation, the Growth Hormone Receptor (GHR) Exon 3 Deletion Polymorphism in a West-African Population

    Millar, David S.; Lewis, Mark D.; Horan, Martin; Newsway, Vicky; Rees, D Aled; Easter, Tammy E.; Pepe, Guglielmina; Rickards, Olga; Norin, Martin; Scanlon, Maurice F.; Krawczak, Michael; Cooper, David N.


    Growth Hormone (GH1) Gene Variation, the Growth Hormone Receptor (GHR) Exon 3 Deletion Polymorphism in a West-African Population UNITED KINGDOM (Millar, David S.) UNITED KINGDOM Received: 2008-05-29 Revised: 2008-08-21 Accepted: 2008-09-22

  11. Expression profile and prognostic role of sex hormone receptors in gastric cancer

    Increasing interest has been devoted to the expression and possible role of sex hormone receptors in gastric cancer, but most of these findings are controversial. In the present study, the expression profile of sex hormone receptors in gastric cancer and their clinicopathological and prognostic value were determined in a large Chinese cohort. The mRNA and protein expression of estrogen receptor alpha (ERα), estrogen receptor beta (ERβ), progesterone receptor (PR), and androgen receptor (AR) in primary gastric tumors and corresponding adjacent normal tissues from 60 and 866 Chinese gastric cancer patients was detected by real-time quantitative PCR and immunohistochemistry method, respectively. The expression profile of the four receptors was compared and their associations with clinicopathological characteristics were assessed by using Chi-square test. The prognostic value of the four receptors in gastric cancer was evaluated by using univariate and multivariate Cox regression analysis. The presence of ERα, ERβ, PR, and AR in both gastric tumors and normal tissues was confirmed but their expression levels were extremely low except for the predominance of ERβ. The four receptors were expressed independently and showed a decreased expression pattern in gastric tumors compared to adjacent normal tissues. The positive expression of the four receptors all correlated with high tumor grade and intestinal type, and ERα and AR were also associated with early TNM stage and thereby a favorable outcome. However, ERα and AR were not independent prognostic factors for gastric cancer when multivariate survival analysis was performed. Our findings indicate that the sex hormone receptors may be partly involved in gastric carcinogenesis but their clinicopathological and prognostic significance in gastric cancer appears to be limited

  12. Ability of luteinizing hormone releasing hormone-Pseudomonas aeruginosa exotoxin 40 binding to LHRH receptor on human liver cancer cells

    Shou-Liang Gong; Gang Zhao; Hong-Guang Zhao; Wen-Tian Lü; Guang-Wei Liu; Ping Zhu


    AIM: To explore the ability of recombinant toxin luteinizing hormone releasing hormone-Pseudomonas aeruginosa exotoxin 40 (LHRH-PE40) anH binding to LHRH receptor(LHRHR) on the membrane surfa ogf hman liver cancer HEPG cells.METHODS: LHRH was beled by using 125I with enzymatic reaction. The affinity and receptor volume of LHRH-PE40and LHRH binding to LHRHR on the membrane surface of human liver cancer cells were measured with radioligand receptor assay.RESULTS:The specific activity of LHRH labeled with 125I was 2.7×104 kBq/μL, and its radiochemical purity reached to 99.2-99.7%. The binding of 125I to LHRH was maximal for 240 min in the warm cultivation, and this binding was stabilized. The inhibiting rates of 125I-LHRH and LHRH on the proliferation of human liver cancer HEPG cells were not significantly different. On the basis of the saturation curve of 125I-LHRH binding to the membrane LHRHR of HEPG cells, 125I-LHRH of 1×105 cpm was selected for radioligand receptor assay. The affinity constants (Kd) of LHRH-PE40and LHRH bively,and their receptor volumes were 0.37±0.15 μmol/g and0.42±0.13 μmol/g, respectively. The binding of LHRH-PE40to the membrane proteinof normal liver cells was not observed.CONCLUSION: The recombinant toxin LHRH-PE40 binding to the membrane surface of LHRHR of human liver cancer HEPG cells was very strong, while the specific binding of it to normal liver cells was not observed. The results provide an important experimental basis for the clinical application of LHRH-PE.

  13. A new mutation in the thyroid hormone receptor gene of a Chinese family with resistance to thyroid hormone

    DONG Qian; GONG Chun-xiu; GU Yi; SU Chang


    Background Resistance to thyroid hormone (RTH) is a dominant inherited syndrome of reduced tissue responsiveness to thyroid hormone. It is usually due to mutations located at the ligand-binding domain and adjacent hinge region of the thyroid hormone receptor β(TRβ). We report the clinical and laboratory characteristics and the genetic analysis of a patient with this rare disorder and his family members.Methods The clinical presentations and changes of thyroid function tests (TFTs) including magnetic resonance imaging (MRI) of pituitary and other laboratory tests were analysed. TFTs of his family's members were detected as well. Direct DNA sequencing of the TRβ gene was done for those with abnormal TFTs.Results The RTH child had goiter, irritability, aggressiveness, and sudoresis. His TFTs showed high levels of circulating free thyroid hormones (FT4 and FT3) and normal thyroid-stimulating hormone (TSH) concentrations. He felt worse when treated as hyperthyroidism (Grave disease) with thiamazole and his clinical presentations got improved obviously when treated as RTH with bromocriptine without obvious advert effect. We identified a novel missense mutation, A317D, located in exon 9 of the gene of this boy and his mother. His mother had not any clinical presentation, but having abnormal TFTs results.Conclusions This patient reported here was concordant with the criteria of RTH. The feature is dysfunction of hypothalamus-pituitary-thyroid axis. A novel mutation was found in the TRβ, A317D, of this family. This research verified the phenomena that there is a clinical heterogeneity within the same mutation of different RTH patients.

  14. The mineralocorticoid hormone receptor and action in the eye.

    Mirshahi, M; Nicolas, C; Mirshahi, A; Hecquet, C; d'Hermies, F; Faure, J P; Agarwal, M K


    Immunoblotting with a polyclonal antibody, directed against the mineralocorticoid receptor protein purified from rat kidney in presence of the receptor-specific ligand RU 26752, labeled a single 98-102 kDa band in soluble extracts from bovine retina and from cultured bovine retinal pigment epithelial cells, identical to the receptor in several other tissues from the rat. The antibody also immunoprecipitated the receptor-3H-RU 26752 complex in bovine retinal extract. The growth of the isolated pigment epithelial cells was inhibited by RU 26752 and ZK91587, two ligands specific to the mineralocorticoid receptor. Successive passages in culture led to the disappearance of immunoreactivity in Western blots, concurrently with the refractoriness of the cells to growth inhibition by the two antagonists. On sections of the human eye, mineralocorticoid receptor-specific immunofluorescence was observed in retinal cone cells, pigment epithelium, epithelium of ciliary body, iris, cornea and lens. To our knowledge, this is the first ever demonstration of the mineralocorticoid receptor in ocular tissues. PMID:8619799

  15. Hormone stimulation of androgen receptor mediates dynamic changes in DNA methylation patterns at regulatory elements

    Dhiman, Vineet K; Attwood, Kristopher; Campbell, Moray J.; Smiraglia, Dominic J


    DNA methylation is an epigenetic modification that contributes to stable gene silencing by interfering with the ability of transcriptional regulators to bind to DNA. Recent findings have revealed that hormone stimulation of certain nuclear receptors induces rapid, dynamic changes in DNA methylation patterns alongside transcriptional responses at a subset of target loci, over time. However, the ability of androgen receptor (AR) to dynamically regulate gene transcription is relatively under-stu...

  16. Distinct growth hormone receptor signaling modes regulate skeletal muscle development and insulin sensitivity in mice

    Mavalli, Mahendra D.; DiGirolamo, Douglas J.; Fan, Yong; Riddle, Ryan C.; Campbell, Kenneth S.; van Groen, Thomas; Frank, Stuart J.; Sperling, Mark A.; Esser, Karyn A; Bamman, Marcas M; Clemens, Thomas L.


    Skeletal muscle development, nutrient uptake, and nutrient utilization is largely coordinated by growth hormone (GH) and its downstream effectors, in particular, IGF-1. However, it is not clear which effects of GH on skeletal muscle are direct and which are secondary to GH-induced IGF-1 expression. Thus, we generated mice lacking either GH receptor (GHR) or IGF-1 receptor (IGF-1R) specifically in skeletal muscle. Both exhibited impaired skeletal muscle development characterized by reductions ...

  17. NHERF1 Regulates Parathyroid Hormone Receptor Desensitization: Interference with β-Arrestin BindingS⃞

    Wang, Bin; Yang, Yanmei; Abou-Samra, Abdul B.; Friedman, Peter A.


    Type 1 parathyroid hormone receptor (PTH1R) activation, desensitization, internalization, and recycling proceed in a cyclical manner. The Na+/H+ exchange regulatory factor 1 (NHERF1) is a cytoplasmic adapter protein that regulates trafficking and signaling of several G protein-coupled receptors (GPCRs) including the PTH1R. The mineral ion wasting and bone phenotype of NHERF1-null mice suggests that PTH1R may interact with NHERF1. The objective of this study was to exam...

  18. Enzymatic Regulation of Steroidogenesis and Nuclear Receptor Activation : Special Focus on Vitamin D and Sex Hormones



    Enzyme-catalyzed reactions are important to regulate steroidogenesis and nuclear receptor activation. The present investigation examines the role of steroid metabolism catalyzed by CYP7B1 for regulation of hormone receptor activation and the effects of vitamin D on enzymatic regulation of steroidogenesis. The study reports data indicating that CYP7B1 can regulate estrogenic signaling by converting estrogens into inactive or less active metabolites. Similar results were obtained for CYP7B1-med...

  19. Growth hormone receptor expression and function in pituitary adenomas

    Clausen, Lene R; Kristiansen, Mikkel T; Rasmussen, Lars M;


    OBJECTIVE AND DESIGN: Hypopituitarism, in particular GH deficiency, is prevalent in patients with clinically nonfunctioning pituitary adenomas (NFPAs) both before and after surgery. The factors regulating the growth of pituitary adenomas in general and residual tumour tissue in particular are not...... transcription 5) phosphorylation was measured by Western blot analysis as an index of GHR signalling; cell proliferation was evaluated by [H3]-thymidine incorporation and glycoprotein hormone production analysed by radioimmunoassay (RIA). RESULTS: All adenomas investigated expressed the GHR, but there was no...... detection of STAT5 phosphorylation. Overall, GH and IGF-I administration did not significantly stimulate cell proliferation in vitro, although some individual adenomas exhibited a proliferative response to various extents. GH also did not significantly influence glycoprotein hormone secretion in vitro...

  20. Expression of the growth hormone receptor gene in insulin producing cells

    Møldrup, Annette; Billestrup, N; Nielsen, Jens Høiriis


    Growth hormone (GH) plays a dual role in glucose homeostasis. On the one hand, it exerts an insulin antagonistic effect on the peripheral tissue, on the other hand, it stimulates insulin biosynthesis and beta-cell proliferation. The expression of GH-receptors on the rat insulinoma cell line RIN-5...

  1. Steroid hormone receptor expression in ovarian cancer: progesterone receptor B as prognostic marker for patient survival

    There is partially conflicting evidence on the influence of the steroid hormones estrogen (E) and progesterone (P) on the development of ovarian cancer (OC). The aim of this study was to assess the expression of the receptor isoforms ER-α/-β and PR-A/-B in OC tissue and to analyze its impact on clinical and pathological features and patient outcome. 155 OC patients were included who had been diagnosed and treated between 1990 and 2002. Patient characteristics, histology and follow-up data were available. ER-α/-β and PR-A/-B expression were determined by immunohistochemistry. OC tissue was positive for ER-α/-β in 31.4% and 60.1% and PR-A/-B in 36.2% and 33.8%, respectively. We identified significant differences in ER-β expression related to the histological subtype (p=0.041), stage (p=0.002) and grade (p=0.011) as well as PR-A and tumor stage (p=0.03). Interestingly, median receptor expression for ER-α and PR-A/-B was significantly higher in G1 vs. G2 OC. Kaplan Meier analysis revealed a good prognosis for ER-α positive (p=0.039) and PR-B positive (p<0.001) OC. In contrast, ER-β negative OC had a favorable outcome (p=0.049). Besides tumor grade and stage, Cox-regression analysis showed PR-B to be an independent prognostic marker for patient survival (p=0.009, 95% CI 0.251-0.823, HR 0.455). ER-α/-β and PR-A/-B are frequently expressed in OC with a certain variability relating to histological subtype, grade and stage. Univariate analysis indicated a favorable outcome for ER-α positive and PR-B positive OC, while multivariate analysis showed PR-B to be the only independent prognostic marker for patient survival. In conclusion, ER and PR receptors may be useful targets for a more individualized OC therapy

  2. Expression of thyroid stimulating hormone receptor in differentiated thyroid carcinoma and its clinical significance



    Objective To explore the expression of thyroid stimulating hormone (TSH) receptor in differentiated thyroid carcinoma and its clinical significance.Methods Seventy-four patients with differentiated thyroid carcinoma treated in our department from January 2009 to January 2011were selected as the observation group,and 28 patients with nodular goiter were selected as the control group.Expression of TSH receptor in the two groups were detected by immunohistochemistry.Results The positive rate of TSH receptor expression in the observation group was55.4 (41/74) ,significantly lower than that of the control

  3. Dimeric Arrangement of the Parathyroid Hormone Receptor and a Structural Mechanism for Ligand-induced Dissociation

    Pioszak, Augen A.; Harikumar, Kaleeckal G.; Parker, Naomi R.; Miller, Laurence J.; Xu, H. Eric (Van Andel); (Mayo)


    The parathyroid hormone receptor (PTH1R) is a class B G protein-coupled receptor that is activated by parathyroid hormone (PTH) and PTH-related protein (PTHrP). Little is known about the oligomeric state of the receptor and its regulation by hormone. The crystal structure of the ligand-free PTH1R extracellular domain (ECD) reveals an unexpected dimer in which the C-terminal segment of both ECD protomers forms an {alpha}-helix that mimics PTH/PTHrP by occupying the peptide binding groove of the opposing protomer. ECD-mediated oligomerization of intact PTH1R was confirmed in living cells by bioluminescence and fluorescence resonance energy transfer experiments. As predicted by the structure, PTH binding disrupted receptor oligomerization. A receptor rendered monomeric by mutations in the ECD retained wild-type PTH binding and cAMP signaling ability. Our results are consistent with the hypothesis that PTH1R forms constitutive dimers that are dissociated by ligand binding and that monomeric PTH1R is capable of activating G protein.

  4. Epidermal dexamethasone receptors in dogs with confirmed hyperadrenocorticalism, hypothyroidism or undiagnosed hormonal alopecia.

    van den Broek, A H; Stafford, W L


    Low capacity, high affinity [3H] dexamethasone binding receptors were identified in cytosolic preparations of the skin (mean number 42.0 +/- 25.2 fmol mg-1 protein, apparent dissociation constant (1 nM +/- 0.23) of clinically normal dogs. No [3H] dexamethasone binding was observed in the skin of nine out of 10 dogs with confirmed spontaneous hyperadrenocorticism or in the skin of three out of six dogs with undiagnosed hormonal alopecia. A reduction was detected in the number of [3H] dexamethasone binding receptors in the skin of one dog with confirmed hypothyroidism. This study provides evidence for the susceptibility of canine glucocorticoid receptors to down regulation by imbalances of endogenous hormones, particularly increased glucocorticoid concentrations. PMID:1780592

  5. Changes in parathyroid hormone receptor binding affinity during egg laying: implications for calcium homeostasis in chicken.

    Yasuoka, T; Kawashima, M; Takahashi, T; Iwata, A; Oka, N; Tanaka, K


    Parathyroid hormone (PTH) receptor bindings were examined in the membrane fraction of the calvaria and the kidney of the hen by the use of [125I]PTH-related protein (PTHrP) binding assays. The binding specificity, reversibility, and saturation of the receptor were demonstrated. The equilibrium dissociation constant (Kd) and the maximum binding capacity (Bmax) were obtained by Scatchard analyses. In both calvaria and kidney, Kd and Bmax values decreased at 3 h before oviposition in egg-laying hens, but not in nonlaying hens. Administration of 17 beta-estradiol or progesterone in vivo caused a decrease in the Kd and Bmax values. Ionized calcium concentrations in the blood plasma showed a decrease at 13 h before oviposition. The results suggest that the PTH receptor binding in the calvaria and the kidney is affected by ovarian steroid hormones and may play a role in maintaining the calcium homeostasis in the egg-laying hen. PMID:8970893

  6. Reconstitution of hormone-responsive detergent-solubilized follicle stimulating hormone receptors into liposomes

    An FSH receptor-enriched fraction that responds to exogenous FSH by activation of adenylate cyclase was prepared by ultrafiltration of sucrose density gradient-purified light membranes derived from bovine calf testes homogenates and solubilized with Triton X-100. To further confirm the functional nature of the detergent-solubilized FSH receptor, the extract was incorporated by lipid hydration into large multilamellar vesicles composed of dioleoyl phosphatidylcholine and cholesterol, 2:1 molar ratio. Receptor incorporation was determined by measurement of specific binding of [125I] human FSH ([125I] hFSH). Substitution of dioleoyl phosphatidylcholine with dipalmitoyl phosphatidylcholine or increasing the cholesterol concentration of the vesicles reduced specific binding of [125I]hFSH. Under conditions favoring optimal incorporation of the receptor, specific binding of [125I]hFSH was time and temperature dependent and saturable when increasing concentrations of radioligand were added to a constant amount of proteoliposomes. Reconstituted proteoliposomes bound 1600 fmol FSH/mg protein with an affinity of 3.54 x 10(9) M-1. Inhibition of [125I] hFSH binding by hFSH was comparable to that seen with the membrane-bound receptor (ED50 = 10 ng). Equilibrium binding studies with [3H]Gpp(NH)p indicated that a single class of high affinity GTP binding sites with an association constant (Ka) of 3.33 x 10(7) m-1 which bound 2.19 fmol [3H]Gpp(NH)p/mg protein had also been incorporated into the proteoliposomes. Addition of FSH induced a 2-fold stimulation of [3H]Gpp(NH)p binding, supporting our earlier studies suggesting that the detergent-solubilized FSH receptor is complexed to the G protein. Of particular significance in the present study was the observation that both NaF and FSH stimulated cAMP production in the reconstituted system

  7. Allosteric receptor activation by the plant peptide hormone phytosulfokine.

    Wang, Jizong; Li, Hongju; Han, Zhifu; Zhang, Heqiao; Wang, Tong; Lin, Guangzhong; Chang, Junbiao; Yang, Weicai; Chai, Jijie


    Phytosulfokine (PSK) is a disulfated pentapeptide that has a ubiquitous role in plant growth and development. PSK is perceived by its receptor PSKR, a leucine-rich repeat receptor kinase (LRR-RK). The mechanisms underlying the recognition of PSK, the activation of PSKR and the identity of the components downstream of the initial binding remain elusive. Here we report the crystal structures of the extracellular LRR domain of PSKR in free, PSK- and co-receptor-bound forms. The structures reveal that PSK interacts mainly with a β-strand from the island domain of PSKR, forming an anti-β-sheet. The two sulfate moieties of PSK interact directly with PSKR, sensitizing PSKR recognition of PSK. Supported by biochemical, structural and genetic evidence, PSK binding enhances PSKR heterodimerization with the somatic embryogenesis receptor-like kinases (SERKs). However, PSK is not directly involved in PSKR-SERK interaction but stabilizes PSKR island domain for recruitment of a SERK. Our data reveal the structural basis for PSKR recognition of PSK and allosteric activation of PSKR by PSK, opening up new avenues for the design of PSKR-specific small molecules. PMID:26308901

  8. A 67 kDa non-hormone binding estradiol receptor is present in human mammary cancers.

    Castoria, G; Migliaccio, A; Bilancio, A; Pagano, M; Abbondanza, C; Auricchio, F


    The presence of large amounts of a 67 kDa estradiol receptor that does not bind hormone was observed in 8 to 37 human mammary tumors (34 malignant and 3 benign). This form of receptor was detected by its conversion to hormone binding receptor by an endogenous tyrosine kinase in vitro. All 8 tumors were malignant. In these, the incubation of cytosol with ATP was seen to cause a 1- to 5-fold increase in estradiol-specific binding sites. These sites bound estradiol with physiological affinity, and their appearance was associated with tyrosine phosphorylation of estradiol receptor. The enzyme converting the non-hormone binding receptor into the hormone binding receptor is largely present in cytosol and scarce in membranes. It has been extensively purified. It is a 67 kDa protein under denaturating conditions, binds calmodulin-Sepharose in a Ca2+-dependent manner, is stimulated by Ca2+ and calmodulin, phosphorylates exogenous actin, is activated by the estradiol-receptor complex. The enzyme interacts with antibodies directed against the carboxy-terminal and catalytic domains of c-src. Therefore, it is a putative new member of the large c-src-related kinase family. Human mammary cancers with significant amounts of 67 kDa non-hormone binding receptor show relatively low levels of hormone binding estradiol receptor. The presence of non-hormone binding receptor that can be activated by in vitro tyrosine phosphorylation suggests that functional interaction of estradiol receptor with tyrosine kinases is altered in malignant tumors and has bearing on loss of hormone dependence and progression of the mammary cancer malignancy. PMID:8598306

  9. Development of GR/MR Chimeric Receptors and Their Response to Steroid Hormones


    We have established an effective and reliable technique of developing GR/MR chimeric receptors by DNA homologous recombination. To develop the method we transformed several different E. coli strains with a linearized plasmid containing full length of mGR(mouse GR) and hormone binding domain(HBD) of rMR(rat MR), the linear DNA undergoes recombination due to the homology of the mGR and the rMR and recircularize , and propagation in E. coli. PCR was performed to screen correct construction in which fusion between GR and MR took place. The constructs were digested with appropriate restriction endonucleases to test probable fusion sites of GR and HBD of MR. Precise fusion sites of GR and MR for constructs AB1157 # 2 , AB1157 # 18, AB 1157 # 22, AB1157 # 32, CMK603 # 6 were verified by DNA sequencing. Trans fection of COS- 7 cells with the constructs and subsequent treatment of transfected COS-7 cells with steroid hormones were carried out, the results showed that the constructs gave response to tested hormones. The study suggested that the GR/MR chimeric receptors can give rise to fusion proteins and their interactive function between hormone and receptor.

  10. Correlation between hormone dependency and the regulation of epidermal growth factor receptor by tumor promoters in human mammary carcinoma cells

    The effects of the tumor promoter phorbol 12-tetradecanoate 13-acetate (TPA) on the epidermal growth factor (EGF) receptor levels were investigated in hormone-dependent (MCF-7, T-47-D, and ZR-75-1) and hormone-independent (MDA-MB-231, HBL-100, and BT-20) human mammary carcinoma cell lines. In the absence of TPA, hormone-independent cell lines contained high concentrations of low-affinity EGF receptors, whereas hormone-dependent cell lines exhibited low concentrations of high-affinity receptors. TPA causes a change of the receptor from a high- to the low-affinity state in hormone-dependent cell lines, as well as in the hormone-independent HBL-100, whereas the affinity remained unchanged in MDA-MB-231 and BT-20 cells. Tumor promoters such as TPA or teleocidin inhibited the proliferation of these cell lines at concentrations above 10 μM with the exception of the T-47-D cells. Evaluation of different TPA analogs indicated a positive correlation between the growth-inhibitory effects and their ability to stimulate the subcellular redistribution of protein kinase C activity in MCF-7 cells. These data suggest a protein kinase C-mediated down-regulation of the progesterone receptor concentration and of the EGF receptor affinity, which is supposed to mediate the mitogenic response. Furthermore, these results support the hypothesis that the tumor-derived growth factors induced by estradiol act via the EGF receptor in hormone-dependent mammary carcinoma cells

  11. Rational Design of Potent Antagonists to the Human Growth Hormone Receptor

    Fuh, Germaine; Cunningham, Brian C.; Fukunaga, Rikiro; Nagata, Shigekazu; Goeddel, David V.; Wells, James A.


    A hybrid receptor was constructed that contained the extracellular binding domain of the human growth hormone (hGH) receptor linked to the transmembrane and intracellular domains of the murine granulocyte colony-stimulating factor receptor. Addition of hGH to a myeloid leukemia cell line (FDC-P1) that expressed the hybrid receptor caused proliferation of these cells. The mechanism for signal transduction of the hybrid receptor required dimerization because monoclonal antibodies to the hGH receptor were agonists whereas their monovalent fragments were not. Receptor dimerization occurs sequentially-a receptor binds to site 1 on hGH, and then a second receptor molecule binds to site 2 on hGH. On the basis of this sequential mechanism, which may occur in many other cytokine receptors, inactive hGH analogs were designed that were potent antagonists to hGH-induced cell proliferation. Such antagonists could be useful for treating clinical conditions of hGH excess, such as acromegaly.

  12. Evidence That the Thyroid-stimulating Hormone (TSH) Receptor Transmembrane Domain Influences Kinetics of TSH Binding to the Receptor Ectodomain*

    Chen, Chun-Rong; McLachlan, Sandra M.; Rapoport, Basil


    Thyroid-stimulating hormone (TSH)-induced reduction in ligand binding affinity (negative cooperativity) requires TSH receptor (TSHR) homodimerization, the latter involving primarily the transmembrane domain (TMD) but with the extracellular domain (ECD) also contributing to this association. To test the role of the TMD in negative cooperativity, we studied the TSHR ECD tethered to the cell surface by a glycosylphosphatidylinositol (GPI) anchor that multimerizes despite the absence of the TMD. ...

  13. Disruption of parathyroid hormone and parathyroid hormone-related peptide receptor phosphorylation prolongs ERK1/2 MAPK activation and enhances c-fos expression

    Tawfeek, Hesham A.; Abou-Samra, Abdul B.


    Previous studies have demonstrated that parathyroid hormone (PTH) binding to the PTH/PTH-related peptide receptor (PPR) stimulates G protein coupling, receptor phosphorylation, β-arrestin translocation, and internalization of the ligand/receptor complex. The extracellular signal-regulated mitogen-activated protein kinases 1/2 (ERK1/2 MAPK) are downstream effectors of PPR. In the current study, we investigated the role of PPR phosphorylation in the PTH regulation of the ERK1/2 MAPK pathway. Sh...

  14. Molecular identification of the first insect ecdysis triggering hormone receptors

    Iversen, Annette; Cazzamali, Giuseppe; Williamson, Michael;


    The Drosophila Genome Project website ( contains an annotated gene sequence (CG5911), coding for a G protein-coupled receptor. We cloned the cDNA corresponding to this sequence and found that the gene has not been correctly predicted. The corrected gene CG5911 has five introns and...... six exons (1-6). Alternative splicing yields two cDNAs called A (containing exons 1-5) and B (containing exons 1-4, 6). We expressed these splicing variants in Chinese hamster ovary cells and found that the corrected CG5911-A and -B cDNAs coded for two different G protein-coupled receptors that could...

  15. Polymorphism of growth hormone receptor (GHR gene in Holstein Friesian dairy cattle

    Restu Misrianti


    Full Text Available Growth hormone gene have a critical role in the regulation of lactation, mammary gland development and growth process through its interaction with a specific receptor. Growth hormone (GH is an anabolic hormone which is synthesized and secreted by somatotrop cell in pituitary anterior lobe, and interacts with a specific receptor on the surface of the target cells. Growth hormone receptor (GHR has been suggested as candidate gene for traits related to milk production in Bovidae. The purpose of this study was to identify genetic polymorphism of the Growth Hormone Receptor (GHR genes in Holstein Friesian (HF cattle. Total of 353 blood samples were collected from five populations belonging to Cikole Dairy Cattle Breeding Station (BPPT-SP Cikole (88 samples, Pasir Kemis (95 samples, Cilumber (98 samples, Cipelang Livestock Embryo Center (BET Cipelang (40 samples, Singosari National Artificial Insemination Centre (BBIB Singosari (32 samples and 17 frozen semen samples from Lembang Artificial Insemination Center (BIB Lembang. Genomic DNAs were extracted by a standard phenol-chloroform protocol and amplified by a polymerase chain reaction (PCR techniques then PCR products were genotyped by the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP methods. There were two allele dan three genotypes were found namely: allele A and G, Genotype AA, AG and GG repectively. Allele A frequency (0.70-0.82 relatively higher than allele G frequency (0.18-0.30. Chi square test show that on group of BET Cipelang, BIB Lembang and BBIB Singosari population were not significantly different (0.00-0.93, while on group of BET Cipelang, BIB Lembang dan BBIB Singosari population were significantly different (6.02-11.13. Degree of observed heterozygosity (Ho ranged from 0.13-0.42 and expected heterozygosity (He ranged from 0.29-0.42.

  16. Gonadotropin-inhibitory hormone receptor signaling and its impact on reproduction in chickens.

    Bédécarrats, Grégoy Y; McFarlane, Heather; Maddineni, Sreenivasa R; Ramachandran, Ramesh


    In birds, as in other vertebrates, reproduction is controlled by the hypothalamo-pituitary-gonadal axis with each component secreting specific neuropeptides or hormones. Until recently, it was believed this axis is exclusively under the stimulatory control of hypothalamic gonadotropin-releasing hormone I (GnRH-I) which in turn, stimulates luteinizing hormone (LH) and follicle stimulating hormone (FSH) secretion from the pituitary gland. However, the discovery of a novel inhibitory hypothalamic peptide able to reduce LH secretion (gonadotropin-inhibitory hormone: GnIH) challenged this dogma. Furthermore, with the characterization of its specific receptor (GnIHR), progress has been made to clarify the physiological relevance of GnIH in birds. This short review discusses the recent advances in GnIHR signaling at the level of the pituitary gland and the gonads. GnIHR is a member of the G-protein coupled receptor (GPCR) family which couples to G(alphai) and, upon activation inhibits adenylyl cyclase (AC) activity, thus reducing intracellular cAMP levels. This implies that GnIH interferes with signaling of any GPCR coupled to G(alphas), including GnRH, LH and FSH receptors. In the chicken pituitary gland, the GnRHR-II/GnIHR ratio changes during sexual maturation in favor of GnRHR-II that appears to result in hypothalamic control of gonadotropin secretion shifting from inhibitory to stimulatory, with corresponding changes in GnRH-induced cAMP levels. Within the gonads, GnIH and its receptor may act in an autocrine/paracrine manner and may interfere with LH and FSH signaling to influence ovarian follicular maturation and recruitment, as well as spermatogenesis. PMID:19332068

  17. Transcriptional activation by the thyroid hormone receptor through ligand-dependent receptor recruitment and chromatin remodelling

    Grøntved, Lars; Waterfall, Joshua J; Kim, Dong Wook;


    facilitates recruitment of co-activators to activate transcription. Here we show that in addition to hormone-independent TR occupancy, ChIP-seq against endogenous TR in mouse liver tissue demonstrates considerable hormone-induced TR recruitment to chromatin associated with chromatin remodelling and activated...

  18. Hormone receptor and ERBB2 status in gene expression profiles of human breast tumor samples.

    Anna Dvorkin-Gheva

    Full Text Available The occurrence of large publically available repositories of human breast tumor gene expression profiles provides an important resource to discover new breast cancer biomarkers and therapeutic targets. For example, knowledge of the expression of the estrogen and progesterone hormone receptors (ER and PR, and that of the ERBB2 in breast tumor samples enables choice of therapies for the breast cancer patients that express these proteins. Identifying new biomarkers and therapeutic agents affecting the activity of signaling pathways regulated by the hormone receptors or ERBB2 might be accelerated by knowledge of their expression levels in large gene expression profiling data sets. Unfortunately, the status of these receptors is not invariably reported in public databases of breast tumor gene expression profiles. Attempts have been made to employ a single probe set to identify ER, PR and ERBB2 status, but the specificity or sensitivity of their prediction is low. We enquired whether estimation of ER, PR and ERBB2 status of profiled tumor samples could be improved by using multiple probe sets representing these three genes and others with related expression.We used 8 independent datasets of human breast tumor samples to define gene expression signatures comprising 24, 51 and 14 genes predictive of ER, PR and ERBB2 status respectively. These signatures, as demonstrated by sensitivity and specificity measures, reliably identified hormone receptor and ERBB2 expression in breast tumors that had been previously determined using protein and DNA based assays. Our findings demonstrate that gene signatures can be identified which reliably predict the expression status of the estrogen and progesterone hormone receptors and that of ERBB2 in publically available gene expression profiles of breast tumor samples. Using these signatures to query transcript profiles of breast tumor specimens may enable discovery of new biomarkers and therapeutic targets for

  19. High expression of follicle stimulating hormone receptor in testicular tissue of idiopathic azoospermic patients with severe spermatogenic defects

    Wang Liquan; Huang Hefeng; Jin Fan; Zhou Caiyun; Qian Yuli; Chen Jianhua


    Background Follicle stimulating hormone is necessary for normal reproduction in men.The biochemical actions of follicle stimulating hormone result from binding to the follicle stimulating hormone receptor in the plasma membrane of Sertoli cells.Here,we investigated the expression of the follicle stimulating hormone receptor in different testicular histological phenotypes of patients with idiopathic azoospermia.Methods Fifty-seven cases of idiopathic azoospermia were classified into three groups according to the results of testicular biopsy:patients with hypospermatogenesis,patients with maturation arrest,and patients with Sertoli cell-only syndrome.Thirteen azoospermic patients identified by testicular biopsy as being capable of completing spermatogenesis acted as the control group.Immunohistochemistry and real-time quantitative reverse-transcriptase polymerase chain reaction were performed in each case,and the serum hormone level was also measured in all patients.Results The serum follicle stimulating hormone level in patients with Sertoli cell-only syndrome was significantly higher than in patients with hypospermatogenesis,maturation arrest,and complete spermatogenesis (P<0.01).The serum follicle stimulating hormone level in patients with maturation arrest was significantly higher than in patients with hypospermatogenesis and complete spermatogenesis (P<0.05).There was no difference in serum follicle stimulating hormone levels in patients with hypospermatogenesis and complete spermatogenesis.The follicle stimulating hormone receptor expression level of testicular samples with Sertoli cell-only syndrome was significantly higher than in those with hypospermatogenesis,maturation arrest,and complete spermatogenesis (P<0.05),but no significant difference was observed among hypospermatogenesis,maturation arrest,and complete spermatogenesis testicular samples.Conclusions Different serum follicle stimulating hormone levels and follicle stimulating hormone receptor

  20. Analysis of photoaffinity label derivatives to probe thyroid hormone receptor in human fibroblasts, GH1 cells, and soluble receptor preparations

    The regulation of growth hormone gene expression by thyroid hormone in cultured GH1 cells is mediated by a chromatin-associated receptor. We have previously described a photoaffinity label derivative of 3,5,3'-triiodo-L-thyronine (L-T3) in which the alanine side chain was modified to form N-2-diazo-3,3,3-trifluoropropionyl-L-T3 (L-[125I]T3-PAL). On exposure to 254 nm UV light, L-[125I]T3-PAL generates a carbene which covalently modifies two thyroid hormone receptor forms in intact GH1 cells; an abundant 47,000 Mr species and a less abundant 57,000 Mr form. We have now synthesized similar photoaffinity label derivatives of 3,5,3',5'-tetraiodo-L-thyronine (L-T4) and 3,3',5'-triiodo-L-thyronine (L-rT3). Both compounds identify the same receptor forms in intact cells and in nuclear extracts in vitro as L-[125I]T3-PAL. Labeling by L-[125I]rT3-PAL was low and consistent with the very low occupancy of receptor by L-rT3. Underivatized L-[125I]T3 and L-[125I]T4 labeled the same receptor forms at 254 nm but at a markedly lower efficiency than their PAL derivatives. In contrast, N-bromoacetyl-L-[125I]T3, a chemical affinity labeling agent, did not derivatize either receptor form in vitro. The relative efficiency of coupling to receptor at 254 nm was L-[125I]T4-PAL greater than L-[125I]T3-PAL greater than L-[125I]T4 greater than L-[125I]T3. Although L-[125I]T4-PAL has a lower affinity for receptor than L-[125I]T3-PAL, its coupling efficiency was 5-10-fold higher. This suggests that the alanine side chain of L-[125I]T4-PAL is positioned in the ligand binding region near a residue which is efficiently modified by photoactivation. With L-[125I]T4-PAL we were able to identify three different molecular weight receptor species in human fibroblast nuclei

  1. Parathyroid hormone decreases renal vitamin D receptor expression in vivo

    Healy, Kevin D.; Vanhooke, Janeen L.; Prahl, Jean M.; DeLuca, Hector F.


    The vitamin D receptor (VDR) is a nuclear transcription factor responsible for mediating the biological activities of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. Renal and parathyroid gland VDR content is an important factor in calcium homeostasis, vitamin D metabolism, and the treatment of secondary hyperparathyroidism and renal osteodystrophy. In these tissues, VDR expression is highly regulated by the calcium and vitamin D status. Although 1,25(OH)2D3 up-regulates VDR expression, hypocalcemia ...

  2. Osteopontin deficiency enhances parathyroid hormone/ parathyroid hormone related peptide receptor (PPR) signaling-induced alteration in tooth formation and odontoblastic morphology

    Morishita, Maki; Ono, Noriaki; Miyai, Kentano; Nakagawa, Tomomi; Hanyu, Ryo; Nagao, Masashi; Kamolratanakul, Paksinee; Notomi, Takuya; Rittling, Susan R; Denhardt, David T.; Kronenberg, Henry M.; Ezura, Yoichi; Hayata, Tadayoshi; Nakamoto, Tetsuya; Noda, Masaki


    Parathyroid hormone/parathyroid hormone-related protein receptor (PPR) signaling is known to be involved in tooth development. In bone, extracellular matrix protein osteopontin (OPN) is a negative regulator of PPR signaling in bone formation. However, the role of OPN in modulation of PPR action in tooth development is not understood. Therefore, we examined the tooth in double mutant mice. Constitutively active PPR was expressed specifically in the odontoblasts and osteoblasts (caPPR-tg) in th...

  3. Selective induction of apoptosis by the cytotoxic analog AN-207 in cells expressing recombinant receptor for luteinizing hormone-releasing hormone

    Danila, Daniel C; Schally, Andrew V.; Nagy, Attila; Alexander, Joseph M


    The selectivity of ligands specific for certain cells can be used to preferentially target chemotherapeutic compounds to neoplastic cells. Human breast, ovarian, endometrial, and prostatic cancers express receptors that can mediate the delivery of targeted cytotoxic compounds to neoplastic cells. Recently, a potent derivative of 2-pyrrolinodoxorubicin (AN-201) conjugated to [d-Lys6] luteinizing hormone-releasing hormone (LH-RH) (AN-207), was demonstrated to be less toxic than the nonconjugate...

  4. Study of change of sex hormone receptors in diabetic impotent patients

    To study the relationship between diabetic impotence and sex hormones as well as sex hormone receptors. 32 diabetic impotent patients, 32 diabetic patients with normal sex function, 32 impotent patients without diabetes, and 40 healthy men were enrolled. The plasma sex hormone levels were examined by radioimmunoassay, and sex hormone receptors in white blood cells by radioreceptor assay. Compared with healthy men and impotent patients without diabetes, PRL levels in both diabetic impotent patients and diabetic patients with normal sex function increased markedly, T and AR levels decreased, and the ratio of E2/T and ER/AR increased. Compared with diabetic patients with normal sex function, while there was no significant difference in PRL, T and E2/T ratio, the AR level of diabetic impotent patients further decreased, and the ER/AR ratio further increased. Negative correlation was found between age and AR as well as T. The decline of AR and the increase of ER/AR ratio might be one main cause of diabetic impotence. And the decline of T and AR might be an important cause of the increase of diabetic impotence incidence with age

  5. Identification of intracellular domains in the growth hormone receptor involved in signal transduction

    Billestrup, N.; Allevato, G.; Moldrup, A. [Hagedorn Research Lab., Gentofte (Denmark)] [and others


    The growth hormone (GH) receptor belongs to the GH/prolactin/cytokine super-family of receptors. The signal transduction mechanism utilized by this class of receptors remains largely unknown. In order to identify functional domains in the intracellular region of the GH receptor we generated a number of GH receptor mutants and analyzed their function after transfection into various cell lines. A truncated GH receptor missing 184 amino acids at the C-terminus was unable to medite GH effects on transcription of the Spi 2.1 and insulin genes. However, this mutant was fully active in mediating GH-stimulated metabolic effects such as protein synthesis and lipolysis. Furthermore, this mutant GH receptor internalized rapidly following GH binding. Another truncated GH receptor lacking all but five amino acids of the cytoplasmic domain could not mediate any effects of GH nor did it internalize. Deletion of the proline-rich region or changing the four prolines to alanines also resulted in a GH receptor deficient in signaling. Mutation of phenylalanine 346 to alanine resulted in a GH receptor which did not internalize rapidly; however, this mutant GH receptor was capable of mediating GH-stimulated transcription as well as metabolic effects. These results indicate that the intracellular part of the GH receptor can be divided into at least three functional domains: (1) for transcriptional activity, two domains are involved, one located in the C-terminal 184 amino acids and the other in the proline-rich domain; (2) for metabolic effects, a domain located in or near the proline-rich region is of importance; and (3) for internalization, phenylalanine 346 is necessary. 28 refs., 1 fig.

  6. Expression of anti-Mullerian hormone receptor on the appendix testis in connection with urological disorders

    Kornél Kistamás; Olga Ruzsnavszky; Andrea Telek; Lívia Kosztka; Ilona Kovács; Beatrix Dienes; László Csernoch


    The female internal sex organs develop from the paramesonephric (Mullerian) duct.In male embryos,the regression of the Mullerian duct is caused by the anti-Mullerian hormone (AMH),which plays an important role in the process of testicular descent.The physiological remnant of the Mullerian duct in males is the appendix testis (AT).In our previous study,we presented evidence for the decreased incidence of AT in cryptorchidism with intraoperative surgery.In this report,the expression of the anti-Mullerian hormone receptor type 2 (AMHR2),the specific receptor of AMH,on the AT was investigated in connection with different urological disorders,such as hernia inguinalis,torsion of AT,cysta epididymis,varicocele,hydrocele testis and various forms of undescended testis.The correlation between the age of the patients and the expression of the AMHR2 was also examined.Reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry were used to detect the receptor's mRNA and protein levels,respectively.We demonstrate that AMHR2 is expressed in the ATs.Additionally,the presence of this receptor was proven at the mRNA and protein levels.The expression pattern of the receptor correlated with neither the examined urological disorders nor the age of the patients;therefore,the function of the AT remains obscure.

  7. A gate-latch-lock mechanism for hormone signalling by abscisic acid receptors

    Melcher, Karsten; Ng, Ley-Moy; Zhou, X Edward; Soon, Fen-Fen; Xu, Yong; Suino-Powell, Kelly M; Park, Sang-Youl; Weiner, Joshua J; Fujii, Hiroaki; Chinnusamy, Viswanathan; Kovach, Amanda; Li, Jun; Wang, Yonghong; Li, Jiayang; Peterson, Francis C; Jensen, Davin R; Yong, Eu-Leong; Volkman, Brian F; Cutler, Sean R; Zhu, Jian-Kang; Xu, H Eric; (NU Sinapore); (Van Andel); (MCW); (UCR); (Chinese Aca. Sci.)


    Abscisic acid (ABA) is a ubiquitous hormone that regulates plant growth, development and responses to environmental stresses. Its action is mediated by the PYR/PYL/RCAR family of START proteins, but it remains unclear how these receptors bind ABA and, in turn, how hormone binding leads to inhibition of the downstream type 2C protein phosphatase (PP2C) effectors. Here we report crystal structures of apo and ABA-bound receptors as well as a ternary PYL2-ABA-PP2C complex. The apo receptors contain an open ligand-binding pocket flanked by a gate that closes in response to ABA by way of conformational changes in two highly conserved β-loops that serve as a gate and latch. Moreover, ABA-induced closure of the gate creates a surface that enables the receptor to dock into and competitively inhibit the PP2C active site. A conserved tryptophan in the PP2C inserts directly between the gate and latch, which functions to further lock the receptor in a closed conformation. Together, our results identify a conserved gate-latch-lock mechanism underlying ABA signalling.

  8. A gate-latch-lock mechanism for hormone signalling by abscisic acid receptors

    Melcher, Karsten


    Abscisic acid (ABA) is a ubiquitous hormone that regulates plant growth, development and responses to environmental stresses. Its action is mediated by the PYR/PYL/RCAR family of START proteins, but it remains unclear how these receptors bind ABA and, in turn, how hormone binding leads to inhibition of the downstream type 2C protein phosphatase (PP2C) effectors. Here we report crystal structures of apo and ABA-bound receptors as well as a ternary PYL2-ABA-PP2C complex. The apo receptors contain an open ligand-binding pocket flanked by a gate that closes in response to ABA by way of conformational changes in two highly conserved ?-loops that serve as a gate and latch. Moreover, ABA-induced closure of the gate creates a surface that enables the receptor to dock into and competitively inhibit the PP2C active site. A conserved tryptophan in the PP2C inserts directly between the gate and latch, which functions to further lock the receptor in a closed conformation. Together, our results identify a conserved gate-latch-lock mechanism underlying ABA signalling. © 2009 Macmillan Publishers Limited. All rights reserved.

  9. Brain volumes in late life: gender, hormone treatment, and estrogen receptor variants.

    Ryan, Joanne; Artero, Sylvaine; Carrière, Isabelle; Scali, Jacqueline; Maller, Jerome; Meslin, Chantal; Ritchie, Karen; Scarabin, Pierre-Yves; Ancelin, Marie-Laure


    Structural imaging studies suggest gender differences in brain volumes; however, whether hormone treatment (HT) can protect against age-related structural changes remains unknown, and no prior neuroimaging study has investigated potential interactions between HT and estrogen receptor (ESR) polymorphisms. Magnetic resonance imaging was used to measure gray and white matter, hippocampal volume, corpus callosum, cerebrospinal fluid (CSF), total intracranial volume (ICV) and white matter lesions ...

  10. 506 Basal T Cell Subpopulations of Normal Humans Vary by Stress Hormone Receptor Polymorphisms

    Rehm, Kristina; Xiang, Lianbin; Marshall, Gailen


    Background Psychological stress has been correlated with allergy and asthma activity although there are clearly individual differences in the responses to the same stressor. These individual differences could be influenced by stress hormone receptor binding affinity, which could be altered by single nucleotide polymorphisms (SNPs). Methods We categorized differences in immunoregulatory profiles from peripheral blood mononuclear cells (PBMC) of 207 normal volunteers according to various glucoc...

  11. Hypermetabolism in mice caused by the central action of an unliganded thyroid hormone receptor α1

    Sjögren, Maria; Alkemade, Anneke; Mittag, Jens; Nordström, Kristina; Katz, Abram; Rozell, Björn; Westerblad, Håkan; Arner, Anders; Vennström, Björn


    Thyroid hormone, via its nuclear receptors TRα and TRβ, controls metabolism by acting locally in peripheral tissues and centrally by regulating sympathetic signaling. We have defined aporeceptor regulation of metabolism by using mice heterozygous for a mutant TRα1 with low affinity to T3. The animals were hypermetabolic, showing strongly reduced fat depots, hyperphagia and resistance to diet-induced obesity accompanied by induction of genes involved in glucose handling and fatty acid metaboli...

  12. The thyroid hormone receptor β induces DNA damage and premature senescence

    Zambrano, Alberto; García-Carpizo, Verónica; Gallardo, M. Esther; Villamuera, Raquel; Gómez-Ferrería, María Ana; Pascual, Ángel; Buisine, Nicolas; Sachs, Laurent M.; Garesse, Rafael; Aranda, Ana


    There is increasing evidence that the thyroid hormone (TH) receptors (THRs) can play a role in aging, cancer and degenerative diseases. In this paper, we demonstrate that binding of TH T3 (triiodothyronine) to THRB induces senescence and deoxyribonucleic acid (DNA) damage in cultured cells and in tissues of young hyperthyroid mice. T3 induces a rapid activation of ATM (ataxia telangiectasia mutated)/PRKAA (adenosine monophosphate- activated protein kinase) signal transduction and recruitment ...

  13. Nuclear receptors for retinoic acid and thyroid hormone regulate transcription of keratin genes.

    Tomic, M; Jiang, C K; Epstein, H S; Freedberg, I M; Samuels, H H; M. Blumenberg


    In the epidermis, retinoids regulate the expression of keratins, the intermediate filament proteins of epithelial cells. We have cloned the 5' regulatory regions of four human epidermal keratin genes, K#5, K#6, K#10, and K#14, and engineered constructs in which these regions drive the expression of the CAT reporter gene. By co-transfecting the constructs into epithelial cells along with the vectors expressing nuclear receptors for retinoic acid (RA) and thyroid hormone, we have demonstrated t...

  14. Modulation of interleukin 2 receptor expression on normal human lymphocytes by thymic hormones.

    Sztein, M B; Serrate, S A; Goldstein, A. L.


    The expression of interleukin 2 receptors (IL-2R) is a critical step leading to normal lymphocyte proliferation. Since thymosin fraction 5 (TF5), a thymic hormone preparation, enhances lymphoproliferative responses of human cells, we examined the effects of TF5 on the expression of IL-2R on mitogen-stimulated human lymphocytes. TF5 significantly increased the percentage and antigen density of cells expressing IL-2R after stimulation with an optimal concentration of phytohemagglutinin (PHA) wh...

  15. Key Regulators of Mitochondrial Biogenesis are Increased in Kidneys of Growth Hormone Receptor Knockout (GHRKO) Mice

    Gesing, Adam; Bartke, Andrzej; Wang, Feiya; Karbownik-Lewinska, Malgorzata; Masternak, Michal M.


    The growth hormone (GH) receptor knockout mice (GHRKO) are remarkably long-lived and highly insulin sensitive. Alterations in mitochondrial biogenesis are associated with aging and various metabolic derangements. We have previously demonstrated increased gene expression of key regulators of mitochondriogenesis in kidneys, hearts and skeletal muscles of GHRKO mice. The aim of the present study was to quantify the protein levels of the following regulators of mitochondriogenesis: peroxisome pro...

  16. Prostate-specific antigen and hormone receptor expression in male and female breast carcinoma

    Cohen Cynthia


    Full Text Available Abstract Background Prostate carcinoma is among the most common solid tumors to secondarily involve the male breast. Prostate specific antigen (PSA and prostate-specific acid phosphatase (PSAP are expressed in benign and malignant prostatic tissue, and immunohistochemical staining for these markers is often used to confirm the prostatic origin of metastatic carcinoma. PSA expression has been reported in male and female breast carcinoma and in gynecomastia, raising concerns about the utility of PSA for differentiating prostate carcinoma metastasis to the male breast from primary breast carcinoma. This study examined the frequency of PSA, PSAP, and hormone receptor expression in male breast carcinoma (MBC, female breast carcinoma (FBC, and gynecomastia. Methods Immunohistochemical staining for PSA, PSAP, AR, ER, and PR was performed on tissue microarrays representing six cases of gynecomastia, thirty MBC, and fifty-six FBC. Results PSA was positive in two of fifty-six FBC (3.7%, focally positive in one of thirty MBC (3.3%, and negative in the five examined cases of gynecomastia. PSAP expression was absent in MBC, FBC, and gynecomastia. Hormone receptor expression was similar in males and females (AR 74.1% in MBC vs. 67.9% in FBC, p = 0.62; ER 85.2% vs. 68.5%, p = 0.18; and PR 51.9% vs. 48.2%, p = 0.82. Conclusions PSA and PSAP are useful markers to distinguish primary breast carcinoma from prostate carcinoma metastatic to the male breast. Although PSA expression appeared to correlate with hormone receptor expression, the incidence of PSA expression in our population was too low to draw significant conclusions about an association between PSA expression and hormone receptor status in breast lesions.

  17. UV filters induce transcriptional changes of different hormonal receptors in Chironomus riparius embryos and larvae.

    Ozáez, Irene; Aquilino, Mónica; Morcillo, Gloria; Martínez-Guitarte, José-Luis


    Organic ultraviolet (UV) filters are emerging contaminants that are ubiquitous in fresh and marine aquatic systems due to their extensive use in cosmetics, plastics, paints, textiles, and many other industrial products. The estrogenic effects of organic UV filters have been long demonstrated in vertebrates, and other hormonal activities may be altered, according to more recent reports. The impact of UV filters on the endocrine system of invertebrates is largely unknown. We have previously reported that some UV filters may affect ecdysone-related genes in the aquatic insect Chironomus riparius, an ecotoxicologically important model organism. To further analyze other possible effects on endocrine pathways, we first characterized four pivotal genes related with hormonal pathways in insects; thereafter, these genes were assessed for alterations in transcriptional activity after exposure to 4-methylbenzylidene camphor (4MBC) or benzophenone-3 (BP-3), two extensively used sunscreens. We found that both chemicals disturbed the expression of all four genes analyzed: hormonal receptor 38 (HR38), methoprene-tolerant (Met), membrane-associate progesterone receptor (MAPR) and insulin-like receptor (INSR), measured by changes in mRNA levels by real-time PCR. An upregulatory effect at the genomic level was detected in different developmental stages. Interestingly, embryos appeared to be more sensitive to the action of the UV filters than larvae. Our results suggest that the risk of disruption through different endocrine routes is not negligible, considering the significant effects of UV filters on key hormonal receptor and regulatory genes. Further effort is needed to develop environmental risk assessment studies on these pollutants, particularly for aquatic invertebrate model organisms. PMID:27089421

  18. The Relationship Between Gene Polymorphism of Leptin and Leptin Receptor and Growth Hormone Deficiency

    He, Jinshui; Fang, Yanling; Lin, Xinfu; Zhou, Huowang; ZHU, SHAOBO; Zhang, Yugui; Yang, Huicong; Ye, Xiaoling


    Backgrounds Growth hormone deficiency (GHD) is a major cause of congenital short stature. GHD patients have significantly decreased serum leptin levels, which are regulated by gene polymorphism of leptin and leptin receptor. This study thus investigated the relationship between gene polymorphism and susceptibility to GHD. Material/Methods A case-control study was performed using 180 GHD children in addition to 160 healthy controls. After the extraction of whole genomic DNA, the genotypes of l...

  19. Antagonizing the parathyroid calcium receptor stimulates parathyroid hormone secretion and bone formation in osteopenic rats

    Gowen, Maxine; Stroup, George B.; Dodds, Robert A; James, Ian E.; Votta, Bart J.; Smith, Brian R.; Bhatnagar, Pradip K.; Lago, Amparo M.; Callahan, James F.; DelMar, Eric G.; Miller, Michael A.; Nemeth, Edward F.; Fox, John


    Parathyroid hormone (PTH) is an effective bone anabolic agent, but it must be administered parenterally. An orally active anabolic agent would provide a valuable alternative for treating osteoporosis. NPS 2143 is a novel, selective antagonist (a “calcilytic”) of the parathyroid cell Ca2+ receptor. Daily oral administration of NPS 2143 to osteopenic ovariectomized (OVX) rats caused a sustained increase in plasma PTH levels, provoking a dramatic increase in bone turnover but no net change in bo...

  20. Involvement of Ghrelin-Growth Hormone Secretagogue Receptor System in Pathoclinical Profiles of Digestive System Cancer

    Zhigang WANG; Weigang WANG; Wencai QIU; Youben FAN; Jun ZHAO; Yu WANG; Qi ZHENG


    Ghrelin receptor has been shown to be expressed along the human gastrointestinal tract.Recent studies showed that ghrelin and a synthetic ghrelin receptor agonist improved weight gain and lean body mass retention in a rat model of cancer cachexia by acting on ghrelin receptor, that is, growth hormone secretagogue receptor (GHS-R). This study aims to explore the expression and the distribution of ghrelin receptor in human gastrointestinal tract cancers and to investigate the possible involvement of the ghrelin-GHS-R system in human digestive cancers. Surgical human digestive cancer specimens were obtained from various portions of the gastrointestinal tract from different patients. The expression of ghrelin receptor in these tissues was detected by tissue microarray technique. Our results showed that ghrelin receptor was expressed in cancers throughout the gastrointestinal tract, mainly in the cytoplasm of mucosal layer cells.Its expression level possibly correlated with organ type, histological grade, tumor-nodes-metastases stage,and nutrition status (weight loss) of the patients. For the first time, we identified the distribution of ghrelin receptor in digestive system cancers. Our results implied that the ghrelin-GHS-R system might be involved in the pathoclinical profiles of digestive cancers.

  1. Receptors of Hypothalamic-Pituitary-Ovarian-Axis Hormone in Uterine Myomas

    Danuta Plewka


    Full Text Available In this study the expression of GnRH, FSH, LH, ER-α, ER-β, and PR receptors was examined in uterine myomas of women in reproductive and perimenopausal age. In cases of GnRH and tropic hormones a membranous and cytoplasmic immunohistochemical reaction was detected, in cases of ER-α and PR the reaction was located in cell nucleus, and in the case of ER-β it manifested also a cytoplasmic location. In some of the examined cases the expression was detected in endometrium, myocytes, and endothelium of blood vessels, in uterine glands and myoma cells. In myometrium the level of GnRH and LH receptors increases with age, whereas the level of progesterone and both estrogen receptors decreases. In myomas of women in reproductive age, independently of their size, expression of GnRH, FSH, and LH receptors was more pronounced than in myometrium. In women of perimenopausal age, independently of myoma size, expression of LH and estrogen α receptors was higher while expression of GnRH receptors was lower than in myometrium. FSH receptor expression was not observed. Expression of estrogen receptor β was not affected by age of the woman or size of myoma. Analysis of obtained results indicates on existing in small myomas local feedback axis between GnRH-LH-progesterone.

  2. Height, age at menarche and risk of hormone receptor-positive and -negative breast cancer: A cohort study

    Ritte, R.; Lukanova, A.; Tjonneland, A.; Olsen, A.; Overvad, K.; Mesrine, S.; Fagherazzi, G.; Dossus, L.; Teucher, B.; Duijnhoven, van F.J.B.


    Associations of breast cancer overall with indicators of exposures during puberty are reasonably well characterized; however, uncertainty remains regarding the associations of height, leg length, sitting height and menarcheal age with hormone receptor-defined malignancies. Within the European Prospe

  3. The Thyroid Hormone Receptors Inhibit Hepatic Interleukin-6 Signaling During Endotoxemia

    Contreras-Jurado, Constanza; Alonso-Merino, Elvira; Saiz-Ladera, Cristina; Valiño, Arturo José; Regadera, Javier; Alemany, Susana; Aranda, Ana


    Decreased thyroidal hormone production is found during lipopolysaccharide (LPS)-induced endotoxic shock in animals as well as in critically ill patients. Here we studied the role of the thyroid hormone receptors (TRs) in activation of STAT3, NF-κB and ERK, which play a key role in the response to inflammatory cytokines during sepsis. TR knockout mice showed down-regulation of hepatic inflammatory mediators, including interleukin 6 (IL-6) in response to LPS. Paradoxically, STAT3 and ERK activity were higher, suggesting that TRs could act as endogenous repressors of these pathways. Furthermore, hyperthyroidism increased cytokine production and mortality in response to LPS, despite decreasing hepatic STAT3 and ERK activity. This suggested that TRs could directly repress the response of the cells to inflammatory mediators. Indeed, we found that the thyroid hormone T3 suppresses IL-6 signalling in macrophages and hepatocarcinoma cells, inhibiting STAT3 activation. Consequently, the hormone strongly antagonizes IL-6-stimulated gene transcription, reducing STAT3 recruitment and histone acetylation at IL-6 target promoters. In conclusion, TRs are potent regulators of inflammatory responses and immune homeostasis during sepsis. Reduced responses to IL-6 should serve as a negative feedback mechanism for preventing deleterious effects of excessive hormone signaling during infections. PMID:27484112

  4. Growth hormone (GH)-independent dimerization of GH receptor by a leucine zipper results in constitutive activation

    Behncken, S N; Billestrup, Nils; Brown, R;


    Growth hormone initiates signaling by inducing homodimerization of two GH receptors. Here, we have sought to determine whether constitutively active receptor can be created in the absence of the extracellular domain by substituting it with high affinity leucine zippers to create dimers of the gro......Growth hormone initiates signaling by inducing homodimerization of two GH receptors. Here, we have sought to determine whether constitutively active receptor can be created in the absence of the extracellular domain by substituting it with high affinity leucine zippers to create dimers...

  5. Extended and Structurally Supported Insights into Extracellular Hormone Binding, Signal Transduction and Organization of the Thyrotropin Receptor

    Krause, Gerd; Kreuchwig, Annika; Kleinau, Gunnar


    The hormone thyrotropin (TSH) and its receptor (TSHR) are crucial for the growth and function of the thyroid gland. The TSHR is evolutionary linked with the receptors of follitropin (FSHR) and lutropin/choriogonadotropin (LHR) and their sequences and structures are similar. The extracellular region of TSHR contains more than 350 amino acids and binds hormone and antibodies. Several important questions related to functions and mechanisms of TSHR are still not comprehensively understood. One ma...

  6. Expression of growth hormone receptor and its mRNA in hepatic cirrhosis

    Hong-Tao Wang; Shuang Chen; Jie Wang; Qing-Jia Ou; Chao Liu; Shu-Sen Zheng; Mei-Hai Deng; Xiao-Ping Liu


    AIM: To investigate the expression of growth hormone receptor (GHR) and mRNA of GHR in cirrhotic livers of rats with the intension to find the basis for application of recombinant human growth hormone (rhGH) to patients with liver cirrhosis.METHODS: Hepatic cirrhosis was induced in SpragueDawley rats by administration of thioacetamide intraperitoneally for 9-12 weeks. Collagenase Ⅳ was perfused in situ for isolation of hepatocytes. The expression of GHR and its mRNA in cirrhotic livers was studied with radio-ligand binding assay, RT-PCR and digital image analysis.RESULTS: One class of specific growth hormone-binding site, GHR, was detected in hepatocytes and hepatic tissue of cirrhotic livers. The binding capacity of GHR (RT, fmol/mg protein) in rat cirrhotic liver tissue (30.8±1.9) was significantly lower than that in normal control (74.9±3.9) at the time point of the ninth week after initiation of induction of cirrhosis (n=10, P<0.05), and it decreased gradually along with the accumulation of collagen in the process of formation and development of liver cirrhosis (P<0.05). The number of binding sites (×10 4/cell) of GHR on rat cirrhotic hepatocytes (0.86±0.16) was significantly lower than that (1.28±0.24)in control (n= 10, P<0.05). The binding affinity of GHR among liver tissue, hepatocytes of various groups had no significant difference (P>0.05). The expression of GHR mRNA (riOD,pixel) in rat cirrhotic hepatic tissues (23.3±3.1) was also significantly lower than that (29.3±3.4) in normal control (n=10, P<0.05).CONCLUSION: The growth hormone receptor was expressed in a reduced level in liver tissue of cirrhotic rats,and lesser expression of growth hormone receptors was found in a later stage of cirrhosis. The reduced expression of growth hormone receptor was partly due to its decreased expression on cirrhotic hepatocytes and the reduced expression of its mRNA in cirrhotic liver tissue.

  7. Altered metabolism of growth hormone receptor mutant mice: a combined NMR metabonomics and microarray study.

    Horst Joachim Schirra

    Full Text Available BACKGROUND: Growth hormone is an important regulator of post-natal growth and metabolism. We have investigated the metabolic consequences of altered growth hormone signalling in mutant mice that have truncations at position 569 and 391 of the intracellular domain of the growth hormone receptor, and thus exhibit either low (around 30% maximum or no growth hormone-dependent STAT5 signalling respectively. These mutations result in altered liver metabolism, obesity and insulin resistance. METHODOLOGY/PRINCIPAL FINDINGS: The analysis of metabolic changes was performed using microarray analysis of liver tissue and NMR metabonomics of urine and liver tissue. Data were analyzed using multivariate statistics and Gene Ontology tools. The metabolic profiles characteristic for each of the two mutant groups and wild-type mice were identified with NMR metabonomics. We found decreased urinary levels of taurine, citrate and 2-oxoglutarate, and increased levels of trimethylamine, creatine and creatinine when compared to wild-type mice. These results indicate significant changes in lipid and choline metabolism, and were coupled with increased fat deposition, leading to obesity. The microarray analysis identified changes in expression of metabolic enzymes correlating with alterations in metabolite concentration both in urine and liver. Similarity of mutant 569 to the wild-type was seen in young mice, but the pattern of metabolites shifted to that of the 391 mutant as the 569 mice became obese after six months age. CONCLUSIONS/SIGNIFICANCE: The metabonomic observations were consistent with the parallel analysis of gene expression and pathway mapping using microarray data, identifying metabolites and gene transcripts involved in hepatic metabolism, especially for taurine, choline and creatinine metabolism. The systems biology approach applied in this study provides a coherent picture of metabolic changes resulting from impaired STAT5 signalling by the growth hormone

  8. Gonadal steroid hormone receptors and sex differences in the hypothalamo-pituitary-adrenal axis.

    Handa, R J; Burgess, L H; Kerr, J E; O'Keefe, J A


    The rapid activation of stress-responsive neuroendocrine systems is a basic reaction of animals to perturbations in their environment. One well-established response is that of the hypothalamo-pituitary-adrenal (HPA) axis. In rats, corticosterone is the major adrenal steroid secreted and is released in direct response to adrenocorticotropin (ACTH) secreted from the anterior pituitary gland. ACTH in turn is regulated by the hypothalamic factor, corticotropin-releasing hormone. A sex difference exists in the response of the HPA axis to stress, with females reacting more robustly than males. It has been demonstrated that in both sexes, products of the HPA axis inhibit reproductive function. Conversely, the sex differences in HPA function are in part due to differences in the circulating gonadal steroid hormone milieu. It appears that testosterone can act to inhibit HPA function, whereas estrogen can enhance HPA function. One mechanism by which androgens and estrogens modulate stress responses is through the binding to their cognate receptors in the central nervous system. The distribution and regulation of androgen and estrogen receptors within the CNS suggest possible sites and mechanisms by which gonadal steroid hormones can influence stress responses. In the case of androgens, data suggest that the control of the hypothalamic paraventricular nucleus is mediated trans-synaptically. For estrogen, modulation of the HPA axis may be due to changes in glucocorticoid receptor-mediated negative feedback mechanisms. The results of a variety of studies suggest that gonadal steroid hormones, particularly testosterone, modulate HPA activity in an attempt to prevent the deleterious effects of HPA activation on reproductive function. PMID:7729815

  9. Occurrence of xenobiotic ligands for retinoid X receptors and thyroid hormone receptors in the aquatic environment of Taiwan

    Highlights: • Xenobiotic RXR agonists and antagonists were found in river systems in Taiwan. • Potential TR antagonists were mainly detected in water extracts. • Samples collected near the river mouths exhibited high RXR disrupting activity. • RXR/TR antagonist activity in water became stronger after HPLC fractionation. • Bioassays are useful tools to investigate xenobiotic ligands for nuclear receptors. - Abstract: Various synthetic compounds are frequently discharged into the environment via human activities. Among them, certain contaminants may disrupt normal physiological functions of wildlife and humans via interactions with nuclear receptors. To protect human health and the environment, it is important to detect environmental ligands for human nuclear receptors. In this study, yeast-based reporter gene assays were used to investigate the occurrence of xenobiotic ligands for retinoid X receptors (RXR) and thyroid hormone receptors (TR) in the aquatic environment of Taiwan. Experimental results revealed that RXR agonist/antagonist activity was detected in river water and sediment samples. In particular, high RXR agonist/antagonist activity was found in the samples collected near river mouths. Additionally, few samples also elicited significant TR antagonist activity. Our findings show that the aquatic environment of Taiwan was contaminated with RXR and TR ligands. Further study is necessary to identify these xenobiotic RXR and TR agonists and antagonists

  10. Sex hormone receptors in the hypothalamus and their role in sexual differentiation of the male rat brain

    In this investigation, changes in the level of receptors for sex hormones in the hypothalamus and cerebral cortex of male rats were studied on the first through fifth days of postnatal life, and the results obtained were compared with the levels of luteinizing hormone and sex hormones in the peripheral blood in order to discover any correlation between these parameters. 2,4,6,7,-3H-estradiol-17β and 1,2,6,7-3H-testosterone were used as labeled hormones. The values of the association constant and concentration of specific binding sites for estradiol and testosterone in hypothalamus and cerebral cortex of male rats during neonatal development is shown. It is found that in male rats on the first day after birth, receptors for estradiol and testosterone are present and they enable the action both of the testicular hormone and that of estradiol to be realized

  11. Characterization of pituitary growth hormone and its receptor in the green iguana (Iguana iguana).

    Ávila-Mendoza, José; Carranza, Martha; Pérez-Rueda, Ernesto; Luna, Maricela; Arámburo, Carlos


    Pituitary growth hormone (GH) has been studied in most vertebrate groups; however, only a few studies have been carried out in reptiles. Little is known about pituitary hormones in the order Squamata, to which the green iguana (gi) belongs. In this work, we characterized the hypophysis of Iguana iguana morphologically. The somatotrophs (round cells of 7.6-10 μm containing 250- to 300-nm secretory granules where the giGH is stored) were found, by immunohistochemistry and in situ hybridization, exclusively in the caudal lobe of the pars distalis, whereas the lactotrophs were distributed only in the rostral lobe. A pituitary giGH-like protein was obtained by immuno-affinity chromatography employing a heterologous antibody against chicken GH. giGH showed molecular heterogeneity (22, 44, and 88 kDa by SDS-PAGE/Western blot under non-reducing conditions and at least four charge variants (pIs 6.2, 6.5, 6.9, 7.4) by isoelectric focusing. The pituitary giGH cDNA (1016 bp), amplified by PCR and RACE, encodes a pre-hormone of 218 aa, of which 190 aa correspond to the mature protein and 28 aa to the signal peptide. The giGH receptor cDNA was also partially sequenced. Phylogenetic analyses of the amino acid sequences of giGH and giGHR homologs in vertebrates suggest a parallel evolution and functional relationship between the GH and its receptor. PMID:24769041

  12. Genomics, transcriptomics, and peptidomics of Daphnia pulex neuropeptides and protein hormones

    Dircksen, Heinrich; Neupert, Susanne; Predel, Reinhard; Verleyen, Peter; Huybrechts, Jurgen; Strauss, Johannes; Hauser, Frank; Stafflinger, Elisabeth; Schneider, Martina; Pauwels, Kevin; Schoofs, Liliane; Grimmelikhuijzen, Cornelis J P


    We report 43 novel genes in the water flea Daphnia pulex encoding 73 predicted neuropeptide and protein hormones as partly confirmed by RT-PCR. MALDI-TOF mass spectrometry identified 40 neuropeptides by mass matches and 30 neuropeptides by fragmentation sequencing. Single genes encode adipokinetic...

  13. Hormone-induced rearrangement of locust haemolymph lipoproteins The involvement of glycoprotein C2

    Horst, D.J. van der; Doorn, J.M. van; Beenakkers, A.M.Th.


    Formation of lipoprotein A⁺ and elevation of lipoprotein fraction O in locust (Locusta migratoria migratorioides) haemolymph as induced by adipokinetic hormone (AKH) includes the participation of non-lipid carrying proteins (fraction C), which was examined in more detail. By using gel filtration chr

  14. Hormonal enhancement of insecticide efficacy in Tribolium castaneum: Oxidative stress and metabolic aspects

    Plavšin, Ivana; Stašková, Tereza; Šerý, Michal; Smýkal, Vlastimil; Hackenberger, B. K.; Kodrík, Dalibor


    Roč. 170, APR 07 (2015), s. 19-27. ISSN 1532-0456 R&D Projects: GA ČR GA14-07172S Institutional support: RVO:60077344 Keywords : adipokinetic hormone * insecticide * RNA interference Subject RIV: ED - Physiology Impact factor: 2.301, year: 2014

  15. Expansion of microsatellite in the thyroid hormone receptor-alpha1 gene linked to increased receptor expression and less aggressive thyroid cancer

    Onda, Masamitsu; Li, Daisy; Suzuki, Shinichi;


    PURPOSE: The purpose of this study was to determine whether the length of the THRA1 microsatellite, which resides in a noncoding portion of the thyroid hormone receptor-alpha1 gene, affects receptor expression and is linked to clinicopathological parameters in thyroid cancer. EXPERIMENTAL DESIGN:...

  16. Influence of LHRH on sex hormone receptors in the amygdala of the male rat

    Drekić Dmitar M.


    Full Text Available Autoradiography was used to localize estrogen-accumulating cells in the amygdala (AMY, of male rats. with LHRH hormones of seven adult male rats (86 days old. Seven mail rats were each treated with an injection of luteinizing hormone-releasing hormone (LHRH, 25 μg at 83 days old and 3 days later with 250 μCi 3H-estradiol (E2. A control group of male rats was also treated with 250 μCi 3H-E2, two hours before sacrifice. Both groups were sacrificed at 86 days old. In the control group of male rats, the nuclei of the AMY with the highest density of estrogen binding (receptors were nucleus medialis (NM, nucleus corticalis (NCO, nucleus centralis (NCE and massa intercalata (MI of pars corticomedialis of AMY. These nuclei belong to the phylogenetically older corticomedial part of the AMY. Light to moderate labeling was present in the phylogenetically younger nucleus basomedialis (NBM and nucleus basolateralis (NBL. Weak labeling was present in nucleus lateralis anterior (NLA and nucleus lateralis posterior (NLP both from the phylogenetically younger basolateral part of the adult male rat AMY. This distribution of estrogen receptors could be related to the biologically more significant influence of estrogen on the regions of response divergence than on regions of sensory convergence of AMY. In the male rats treated with LHRH 3H-E2, we noticed different a distribution of estrogen receptors, in the different types nuclei of neurons (nucleus of AMY. We observed a smaller number of estrogen receptors in the nucleus of pyramidal neurons, while in fusiform and stellate neurons, a similar number of receptors was present as in the control group for NM, NCO, and NCE. In massa intercalata we found a large numberof receptors in the nuclei of neurons, in the older pars AMY. In younger pars AMY, NBL and NLP, we noticed a significant decrease of receptors for estradiol in the nuclei of pyramidal and fusiform neurons.

  17. Effects of plasticizers and their mixtures on estrogen Receptor and thyroid hormone functions

    Ghisari, Mandana; Bonefeld-Jørgensen, Eva Cecilie


    Plasticizers are additives used to increase the flexibility or plasticity of the material to which they are added, normally rigid plastic and as additives in paint and adhesives. They are suspected to interfere with the endocrine system, including the estrogen and the thyroid hormone (TH) systems....... We investigated in vitro the thyroid hormone-like and estrogenic activities of a range of widely used plasticizers and phenols including benzyl butyl phthalate (BBP), dibutyl phthalate (DBP), dioctyl phthalate (DOP), diisodecyl phthalate (DIDP), diisononyl phthalate (DINP), di-2-ethyl hexyl phthalate...... estrogenic activities of the compounds were assessed in MVLN cells, stably transfected with an estrogen receptor (ER) luciferase reporter vector. Furthermore, the combined effect of a multi-components mixture of six plasticizers was evaluated for its estrogenic and TH-like activities. All the tested...

  18. Patterns of thyroid hormone receptor expression in zebrafish and generation of a novel model of resistance to thyroid hormone action.

    Marelli, Federica; Carra, Silvia; Agostini, Maura; Cotelli, Franco; Peeters, Robin; Chatterjee, Krishna; Persani, Luca


    Resistance to thyroid hormone can be due to heterozygous, dominant negative (DN) THRA (RTHα) or THRB (RTHβ) mutations, but the underlying mechanisms are incompletely understood. Here, we delineate the spatiotemporal expression of TH receptors (TRs) in zebrafish and generated morphants expressing equivalent amounts of wild-type and DN TRαs (thraa_MOs) and TRβs (thrb_MOs) in vivo. Both morphants show severe developmental abnormalities. The phenotype of thraa_MOs includes brain and cardiac defects, but normal thyroid volume and tshba expression. A combined modification of dio2 and dio3 expression can explain the high T3/T4 ratio seen in thraa_MOs, as in RTHα. Thrb_MOs show abnormal eyes and otoliths, with a typical RTHβ pattern of thyroid axis. The coexpression of wild-type, but not mutant, human TRs can rescue the phenotype in both morphants. High T3 doses can partially revert the dominant negative action of mutant TRs in morphant fish. Therefore, our morphants recapitulate the RTHα and RTHβ key manifestations representing new models in which the functional consequences of human TR mutations can be rapidly and faithfully evaluated. PMID:26802880

  19. The Arabidopsis NPR1 Protein Is a Receptor for the Plant Defense Hormone Salicylic Acid

    Yue Wu


    Full Text Available Salicylic acid (SA is an essential hormone in plant immunity, but its receptor has remained elusive for decades. The transcriptional coregulator NPR1 is central to the activation of SA-dependent defense genes, and we previously found that Cys521 and Cys529 of Arabidopsis NPR1's transactivation domain are critical for coactivator function. Here, we demonstrate that NPR1 directly binds SA, but not inactive structural analogs, with an affinity similar to that of other hormone-receptor interactions and consistent with in vivo Arabidopsis SA concentrations. Binding of SA occurs through Cys521/529 via the transition metal copper. Mechanistically, our results suggest that binding of SA causes a conformational change in NPR1 that is accompanied by the release of the C-terminal transactivation domain from the N-terminal autoinhibitory BTB/POZ domain. While NPR1 is already known as a link between the SA signaling molecule and defense-gene activation, we now show that NPR1 is the receptor for SA.

  20. Morphological and Hormonal Identiifcation of Porcine Atretic Follicles and Relationship Analysis of Hormone Receptor Levels During Granulosa Cell Apoptosis In vivo

    YU De-bing; YU Min-li; LIN Fei; JIANG Bao-chun; YANG Li-na; WANG Si-yu; ZHAO Ying; WNAG Zheng-chao


    Recent reports have demonstrated that follicular atresia is initiated or caused by granulosa cell apoptosis followed by theca cell degeneration in mammalian ovaries, but the mechanism of follicular atresia is still to be elucidated. Therefore, our present study was designed to examine our hypothesis that the changes of follicular microenvironment induce the granulosa cell apoptosis during pocrine follicular atresia in vivo. We ifrstly isolated intact porcine antral follicles and identiifed them into three groups, healthy follicles (HF), early atretic follicles (EAF) and progressed atretic follicles (PAF) through morphology and histology. To further conifrm their status, we detected hormone levels in follicular lfuids and the expression level of apoptosis gene Bax in granulosa cells. The rate of progesterone (P) and estradiol (E2) was increased with the expression of Bax, indicating hormone can be used as a marker of granulosa cell apoptosis or follicular atresia. Finally, we analyzed the expression level of hormone receptor genes in granulosa cells and their relationship with follicular atresia. In PAF, the expression of Progesterone receptor (PGR) was increased signiifcantly while estradiol receptor (ER) had no notable changes, which suggesting the increased-PGR accelerated the effect of P-stimulated granulosa cell apoptosis. The dramatic increasing of androgen receptor (AR) expression in PAF and the obvious increase of tumor necrosis factor-αreceptor (TNFR) in EAF indicated that there are different pathways regulating granulosa cell apoptosis during follicular atresia. Together, our results suggested that different pathways of granulosa cell apoptosis was induced by changing the follicular microenvironment during follicular atresia.

  1. 3,5-T2 is an alternative ligand for the thyroid hormone receptor β1.

    Mendoza, A; Navarrete-Ramírez, P; Hernández-Puga, G; Villalobos, P; Holzer, G; Renaud, J P; Laudet, V; Orozco, A


    Several liganded nuclear receptors have alternative ligands acting in a tissue-specific fashion and playing important biological roles. We present evidence that 3,5-diiodothyronine (T(2)), a naturally occurring iodothyronine that results from T(3) outer-ring deiodination, is an alternative ligand for thyroid hormone receptor β1 (TRβ1). In tilapia, 2 TRβ isoforms differing by 9 amino acids in the ligand-binding domain were cloned. Binding and transactivation studies showed that T(2) activates the human and the long tilapia TRβ1 isoform, but not the short one. A chimeric human TRβ1 (hTRβ1) that contained the 9-amino-acid insert showed no response to T(2), suggesting that the conformation of the hTRβ1 naturally allows T(2) binding and that other regions of the receptor are implicated in TR activation by T(2). Indeed, further analysis showed that the N terminus is essential for T(2)-mediated transactivation but not for that by T(3) in the long and hTRβ1, suggesting a functional interaction between the N-terminal domain and the insertion in the ligand-binding domain. To establish the functional relevance of T(2)-mediated TRβ1 binding and activation, mRNA expression and its regulation by T(2) and T(3) was evaluated for both isoforms. Our data show that long TRβ1expression is 10(6)-fold higher than that of the short isoform, and T(3) and T(2) differentially regulate the expression of these 2 TRβ1 isoforms in vivo. Taken together, our results prompted a reevaluation of the role and mechanism of action of thyroid hormone metabolites previously believed to be inactive. More generally, we propose that classical liganded receptors are only partially locked to very specific ligands and that alternative ligands may play a role in the tissue-specific action of receptors. PMID:23736295

  2. Functional heterodimerization of prolactin and growth hormone receptors by ovine placental lactogen.

    Herman, A; Bignon, C; Daniel, N; Grosclaude, J; Gertler, A; Djiane, J


    Although homo- or heterodimerization are common mechanisms for activation of cytokine receptors, cross-talk between two distinct receptors in this superfamily has been never shown. Here we show a physiologically relevant example indicating that such an interaction does occurs, thus raising the hypothesis that heterodimerization between distinct cytokine receptors may be a novel mechanism contributing to the diversity of cytokine signaling. These findings were documented using both surface plasmon resonance and gel filtration experiments and show that ovine placental lactogen (PL) heterodimerizes the extracellular domains (ECDs) of ruminant growth hormone receptor (GHR) and prolactin receptor (PRLR). We also show that PL or PL analogues that exhibit little or no activity in cells transfected with PRLRs and no activity in cells transfected with ovine GHRs exhibit largely enhanced activity in cells cotransfected with both PRLRs and GHRs. Furthermore, chimeric receptors consisting of cytosolic and transmembrane part of ovine GHR or ovine PRLR and ECDs of human granulocyte-macrophage colony-stimulating factor receptor (GM-CSFR) alpha or beta were constructed. Upon transfection into Chinese hamster ovary cells along with reporter luciferase gene and stimulation by GM-CSF, a significant increase in luciferase activity occurred when GM-CSFR-alpha-PRLR and GM-CSFR-beta-GHR or GM-CSFR-alpha-GHR and GM-CSRR-beta-PRLR were cotransfected. In conclusion, we show that ovine PL is capable of functional heterodimerization of GHR and PRLR and that when their cytosolic parts, coupled to the ECD of GM-CSF receptors, are heterodimerized by GM-CSF, they are capable of transducing biological signal. PMID:10692427

  3. Pumpkin seed extract: Cell growth inhibition of hyperplastic and cancer cells, independent of steroid hormone receptors.

    Medjakovic, Svjetlana; Hobiger, Stefanie; Ardjomand-Woelkart, Karin; Bucar, Franz; Jungbauer, Alois


    Pumpkin seeds have been known in folk medicine as remedy for kidney, bladder and prostate disorders since centuries. Nevertheless, pumpkin research provides insufficient data to back up traditional beliefs of ethnomedical practice. The bioactivity of a hydro-ethanolic extract of pumpkin seeds from the Styrian pumpkin, Cucurbita pepo L. subsp. pepo var. styriaca, was investigated. As pumpkin seed extracts are standardized to cucurbitin, this compound was also tested. Transactivational activity was evaluated for human androgen receptor, estrogen receptor and progesterone receptor with in vitro yeast assays. Cell viability tests with prostate cancer cells, breast cancer cells, colorectal adenocarcinoma cells and a hyperplastic cell line from benign prostate hyperplasia tissue were performed. As model for non-hyperplastic cells, effects on cell viability were tested with a human dermal fibroblast cell line (HDF-5). No transactivational activity was found for human androgen receptor, estrogen receptor and progesterone receptor, for both, extract and cucurbitin. A cell growth inhibition of ~40-50% was observed for all cell lines, with the exception of HDF-5, which showed with ~20% much lower cell growth inhibition. Given the receptor status of some cell lines, a steroid-hormone receptor independent growth inhibiting effect can be assumed. The cell growth inhibition for fast growing cells together with the cell growth inhibition of prostate-, breast- and colon cancer cells corroborates the ethnomedical use of pumpkin seeds for a treatment of benign prostate hyperplasia. Moreover, due to the lack of androgenic activity, pumpkin seed applications can be regarded as safe for the prostate. PMID:26976217

  4. Salt Bridges Overlapping the Gonadotropin-Releasing Hormone Receptor Agonist Binding Site Reveal a Coincidence Detector for G Protein-Coupled Receptor Activation

    Janovick, Jo Ann; Pogozheva, Irina D.; Mosberg, Henry I.; Conn, P. Michael


    G protein-coupled receptors (GPCRs) play central roles in most physiological functions, and mutations in them cause heritable diseases. Whereas crystal structures provide details about the structure of GPCRs, there is little information that identifies structural features that permit receptors to pass the cellular quality control system or are involved in transition from the ground state to the ligand-activated state. The gonadotropin-releasing hormone receptor (GnRHR), because of its small s...

  5. Receptors and effects of gut hormones in three osteoblastic cell lines

    Wilson Peter JM


    Full Text Available Abstract Background In recent years the interest on the relationship of gut hormones to bone processes has increased and represents one of the most interesting aspects in skeletal research. The proportion of bone mass to soft tissue is a relationship that seems to be controlled by delicate and subtle regulations that imply "cross-talks" between the nutrient intake and tissues like fat. Thus, recognition of the mechanisms that integrate a gastrointestinal-fat-bone axis and its application to several aspects of human health is vital for improving treatments related to bone diseases. This work analysed the effects of gut hormones in cell cultures of three osteoblastic cell lines which represent different stages in osteoblastic development. Also, this is the first time that there is a report on the direct effects of glucagon-like peptide 2, and obestatin on osteoblast-like cells. Methods mRNA expression levels of five gut hormone receptors (glucose-dependent insulinotropic peptide [GIP], glucagon-like peptide 1 [GLP-1], glucagon-like peptide 2 [GLP-2], ghrelin [GHR] and obestatin [OB] were analysed in three osteoblastic cell lines (Saos-2, TE-85 and MG-63 showing different stages of osteoblast development using reverse transcription and real time polymerase chain reaction. The responses to the gut peptides were studied using assays for cell viability, and biochemical bone markers: alkaline phosphatase (ALP, procollagen type 1 amino-terminal propeptides (P1NP, and osteocalcin production. Results The gut hormone receptor mRNA displayed the highest levels for GIP in Saos-2 and the lowest levels in MG-63, whereas GHR and GPR39 (the putative obestatin receptor expression was higher in TE-85 and MG-63 and lower in Saos-2. GLP-1 and GLP-2 were expressed only in MG-63 and TE-85. Treatment of gut hormones to cell lines showed differential responses: higher levels in cell viability in Saos-2 after GIP, in TE-85 and MG-63 after GLP-1, GLP-2, ghrelin and

  6. Diversification and coevolution of the ghrelin/growth hormone secretagogue receptor system in vertebrates.

    Tine, Mbaye; Kuhl, Heiner; Teske, Peter R; Tschöp, Matthias H; Jastroch, Martin


    The gut hormone ghrelin is involved in numerous metabolic functions, such as the stimulation of growth hormone secretion, gastric motility, and food intake. Ghrelin is modified by ghrelin O-acyltransferase (GOAT) or membrane-bound O-acyltransferase domain-containing 4 (MBOAT4) enabling action through the growth hormone secretagogue receptors (GHS-R). During the course of evolution, initially strong ligand/receptor specificities can be disrupted by genomic changes, potentially modifying physiological roles of the ligand/receptor system. Here, we investigated the coevolution of ghrelin, GOAT, and GHS-R in vertebrates. We combined similarity search, conserved synteny analyses, phylogenetic reconstructions, and protein structure comparisons to reconstruct the evolutionary history of the ghrelin system. Ghrelin remained a single-gene locus in all vertebrate species, and accordingly, a single GHS-R isoform was identified in all tetrapods. Similar patterns of the nonsynonymous (dN) and synonymous (dS) ratio (dN/dS) in the vertebrate lineage strongly suggest coevolution of the ghrelin and GHS-R genes, supporting specific functional interactions and common physiological pathways. The selection profiles do not allow confirmation as to whether ghrelin binds specifically to GOAT, but the ghrelin dN/dS patterns are more similar to those of GOAT compared to MBOAT1 and MBOAT2 isoforms. Four GHS-R isoforms were identified in teleost genomes. This diversification of GHS-R resulted from successive rounds of duplications, some of which remained specific to the teleost lineage. Coevolution signals are lost in teleosts, presumably due to the diversification of GHS-R but not the ghrelin gene. The identification of the GHS-R diversity in teleosts provides a molecular basis for comparative studies on ghrelin's physiological roles and regulation, while the comparative sequence and structure analyses will assist translational medicine to determine structure-function relationships of the

  7. Mutation of thyroid hormone receptor-β in mice predisposes to the development of mammary tumors

    Guigon, CJ; Kim, DW; Willingham, MC; Cheng, S-Y


    Correlative data suggest that thyroid hormone receptor-β (TRβ) mutations could increase the risk of mammary tumor development, but unequivocal evidence is still lacking. To explore the role of TRβ mutants in vivo in breast tumor development and progression, we took advantage of a knock-in mouse model harboring a mutation in the Thrb gene encoding TRβ (ThrbPV mouse). Although in adult nulliparous females, a single ThrbPV allele did not contribute to mammary gland abnormalities, the presence of...

  8. The role of thyroid hormone nuclear receptors in the heart: evidence from pharmacological approaches

    Wiersinga, W.M.


    This review evaluates the hypothesis that the cardiac effects of amiodarone can be explained—at least partly—by the induction of a local ‘hypothyroid-like condition’ in the heart. Evidence supporting the hypothesis comprises the observation that amiodarone exerts an inhibitory effect on the binding of T3 to thyroid hormone receptors (TR) alpha-1 and beta-1 in vitro, and on the expression of particular T3-dependent genes in vivo. In the heart, amiodarone decreases heart rate and alpha myosin h...

  9. Synthesis and Evaluation of Novel Gonadotropin-Releasing Hormone Receptor-Targeting Peptides

    Guo, Haixun; Lu, Jie; Hathaway, Helen; Royce, Melanie E.; Prossnitz, Eric R.; Miao, Yubin


    The purpose of this study was to develop novel radiolabeled gonadotropin-releasing hormone (GnRH) receptor-targeting peptides for breast cancer imaging. Three novel 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-conjugated GnRH peptides were designed and synthesized. The radiometal chelator DOTA was conjugated to the epsilon or alpha amino group of D-lysine, or the epsilon amino group of L-lysine via an Ahx {aminohexanoic acid} linker to generate DOTA-Ahx-(D-Lys6-GnRH1), DOTA...

  10. A single arginine residue determines species specificity of the human growth hormone receptor.

    Souza, S C; Frick, G P; X Wang; Kopchick, J J; Lobo, R B; Goodman, H M


    Although growth hormone (GH) receptors (GHRs) in many species bind human (h) GH as well as their own GH, the hGHR only binds primate GH. Arg43 in hGHR interacts with Asp171 of hGH. Nonprimates have a His in the position equivalent to residue 171 of primate GH and a Leu in position 43 of primate GHR. To determine whether Arg43 accounts for the species specificity of the hGHR, point mutations that changed Leu43 to Arg were introduced into the cDNAs encoding the bovine (b) GHR or the rat GH bind...

  11. Melanin concentrating hormone receptor 1 (MCHR1) antagonists - Still a viable approach for obesity treatment?

    Högberg, T.; Frimurer, T.M.; Sasmal, P.K.


    Obesity is a global epidemic associated with multiple severe diseases. Several pharmacotherapies have been investigated including the melanin concentrating hormone (MCH) and its receptor 1. The development of MCHR1 antagonists are described with a specific perspective on different chemotypes...... investigated in efforts to overcome hERG liabilities while having orally active, potent and selective compounds with sufficient brain penetration. A chemometric comparison of ∼2000 diverse MCHR1 and ∼1000 diverse hERG ligands underline the structural similarities. A binding pocket analysis of a MCHR1 model...

  12. Growth Hormone Receptor Antagonist Treatment Reduces Exercise Performance in Young Males

    Goto, K.; Doessing, S.; Nielsen, R.H.; Flyvbjerg, A.; Kjaer, M.


    Context: The effects of GH on exercise performance remain unclear. Objective: The aim of the study was to examine the effects of GH receptor (GHR) antagonist treatment on exercise performance. Design: Subjects were treated with the GHR antagonist pegvisomant or placebo for 16 d. After the treatment...... period, they exercised to determine exercise performance and hormonal and metabolic responses. Participants: Twenty healthy males participated in the study. Intervention: Subjects were treated with the GHR antagonist (n = 10; 10 mg/d) or placebo (n = 10). After the treatment period, they performed a...

  13. The expression of the pituitary growth hormone-releasing hormone receptor and its splice variants in normal and neoplastic human tissues

    Havt, Alexandre; Andrew V. Schally; Varga József L.; Toller Gábor L.; Horváth Judit E. (New Orleans); Szepesházi Károly; Köster, Frank; Kovitz, Kevin; Groot, Kate; Zarándi Márta; Kanashiro, Celia A.; Halmos Gábor (1962-) (gyógyszerész, receptorfarmakológus, experimentális onkológus)


    Various attempts to detect human pituitary growth hormone-releasing hormone receptor (pGHRH-R) in neoplastic extrapituitary tissues have thus far failed. Recently, four splice variants (SVs) of GHRH-R have been described, of which SV1 has the highest structural homology to pGHRH-R and likely plays a role in tumor growth. The aim of this study was to reinvestigate whether human tumors and normal human extrapituitary tissues express the pGHRH-R and to corroborate our previous findings on its SV...

  14. Juvenile hormone receptors in insect larval epidermis: Identification by photoaffinity labeling

    Tritiated photoaffinity analogs of the natural lepidopteran juvenile hormones, JH I and II (epoxy[3H]bishomofarnesyl diazoacetate ([3H]EHDA) and epoxy[3H]homofarnesyl diazoacetate ([3H]EHDA)), and of the JH analog methoprene ([3H]methoprene diazoketone ([3H]MDK)) were synthesized and used to identify specific JH binding proteins in the larval epidermis of the tobacco hornworm (Manduca sexta). EBDA and EHDA specifically photolabeled a 29-kDa nuclear protein (pI 5.8). This protein and a second 29-kDa protein (pI 6.0) were labeled by MDK, but excess unlabeled methoprene or MDK only prevented binding to the latter. These 29-kDa proteins are also present in larval fat body but not in epidermis from either wandering stage or allatectomized larvae, which lack high-affinity JH binding sites. A 29-kDa nuclear protein with the same developmental specificity as this JH binder bound the DNA of two larval endocuticle genes. A 38-kDa cytosolic protein was also specifically photolabeled by these photoaffinity analogs. The 29-kDa nuclear protein is likely the high-affinity receptor for JH that mediates its genomic action, whereas the 38-kDa cytosolic protein may serve as an intracellular carrier for these highly lipophilic hormones and hormone analogs

  15. Calcium mobilization from fish scales is mediated by parathyroid hormone related protein via the parathyroid hormone type 1 receptor.

    Rotllant, J; Redruello, B; Guerreiro, P M; Fernandes, H; Canario, A V M; Power, D M


    The scales of bony fish represent a significant reservoir of calcium but little is known about their contribution, as well as of bone, to calcium balance and how calcium deposition and mobilization are regulated in calcified tissues. In the present study we report the action of parathyroid hormone-related protein (PTHrP) on calcium mobilization from sea bream (Sparus auratus) scales in an in vitro bioassay. Ligand binding studies of piscine 125I-(1-35(tyr))PTHrP to the membrane fraction of isolated sea bream scales revealed the existence of a single PTH receptor (PTHR) type. RT-PCR of fish scale cDNA using specific primers for two receptor types found in teleosts, PTH1R, and PTH3R, showed expression only of PTH1R. The signalling mechanisms mediating binding of the N-terminal amino acid region of PTHrP were investigated. A synthetic peptide (10(-8) M) based on the N-terminal 1-34 amino acid residues of Fugu rubripes PTHrP strongly stimulated cAMP synthesis and [3H]myo-inositol incorporation in sea bream scales. However, peptides (10(-8) M) with N-terminal deletions, such as (2-34), (3-34) and (7-34)PTHrP, were defective in stimulating cAMP production but stimulated [3H]myo-inositol incorporation. (1-34)PTHrP induced significant osteoclastic activity in scale tissue as indicated by its stimulation of tartrate-resistant acid phosphatase. In contrast, (7-34)PTHrP failed to stimulate the activity of this enzyme. This activity could also be abolished by the adenylyl cyclase inhibitor SQ-22536, but not by the phospholipase C inhibitor U-73122. The results of the study indicate that one mechanism through which N-terminal (1-34)PTHrP stimulates osteoclastic activity of sea bream scales, is through PTH1R and via the cAMP/AC intracellular signalling pathway. It appears, therefore, that fish scales can act as calcium stores and that (1-34)PTHrP regulates calcium mobilization from them; it remains to be established if this mechanism contributes to calcium homeostasis in vivo

  16. Influence of music on steroid hormones and the relationship between receptor polymorphisms and musical ability: a pilot study

    Fukui, Hajime; Toyoshima, Kumiko


    Studies have shown that music confers plasticity to the brain. In a preliminary pilot study, we examined the effect of music listening on steroid hormones and the relationship between steroid hormone receptor polymorphisms and musical ability. Twenty-one subjects (10 males and 11 females) were recruited and divided into musically talented and control groups. The subjects selected (1) music they preferred (chill-inducing music) and (2) music they did not like. Before and after the experiments,...

  17. Effect of two human growth hormone receptor antagonists on glomerulosclerosis in streptozotocin-induced diabetic rats

    Wei LI; Shui-xian SHEN; Li-hua ZHU; En-bi WANG; Zeng-can YE; Jun LIN; Li-he GUO; Fei-hong LUO; Xi-hong LIU; Xin FANG


    AIM: To explore the feasibility of human growth hormone (hGH) receptor antagonist in the treatment of end-stage diabetic renal complications. METHODS: Two hGH mutants, hGHA1 (Cys-hGH-dell-4, G120R, K168A, E174A,C182S, de1186-191) and hGHA2 (hGH-H21A, G120R, E174A) were expressed in E coli. The IC50 (Mean±SD)values for the mutants for inhibiting 125I-hGH binding to rabbit growth hormone receptor were (65±10) ng for hGHA1, (27±5.6) ng for hGHA2, and (10±0.6) ng for wild type hGH, respectively. RESULTS: After treatment for 12 weeks, the renal histology analysis showed that treatment with hGHA2 at 4 mg/kg body weight daily markedly suppressed glomerulosclerosis in streptozotocin-induced diabetic Sprague-Dawley (SD) rats; hGHA1 at the same dosage slightly increased the renal damage compared with saline; while wild type hGH at 1 U/kg body weight daily severely worsened the glomerulo-sclerosis in diabetic SD rats. CONCLUSION: The data indicated that hGHA2 inhibited the end-stage glomerulosclerosis in diabetic rats, but hGHA1 mildly increased the glomerulosclerosis.

  18. Genome inventory and analysis of nuclear hormone receptors in Tetraodon nigroviridis

    Raghu Prasad Rao Metpally; Ramakrishnan Vigneshwar; Ramanathan Sowdhamini


    Nuclear hormone receptors (NRs) form a large superfamily of ligand-activated transcription factors, which regulate genes underlying a wide range of (patho) physiological phenomena. Availability of the full genome sequence of Tetraodon nigroviridis facilitated a genome wide analysis of the NRs in fish genome. Seventy one NRs were found in Tetraodon and were compared with mammalian and fish NR family members. In general, there is a higher representation of NRs in fish genomes compared to mammalian ones. They showed high diversity across classes as observed by phylogenetic analysis. Nucleotide substitution rates show strong negative selection among fish NRs except for pregnane X receptor (PXR), estrogen receptor (ER) and liver X receptor (LXR). This may be attributed to crucial role played by them in metabolism and detoxification of xenobiotic and endobiotic compounds and might have resulted in slight positive selection. Chromosomal mapping and pairwise comparisons of NR distribution in Tetraodon and humans led to the identification of nine syntenic NR regions, of which three are common among fully sequenced vertebrate genomes. Gene structure analysis shows strong conservation of exon structures among orthologoues. Whereas paralogous members show different splicing patterns with intron gain or loss and addition or substitution of exons played a major role in evolution of NR superfamily.

  19. Host target modification as a strategy to counter pathogen hijacking of the jasmonate hormone receptor.

    Zhang, Li; Yao, Jian; Withers, John; Xin, Xiu-Fang; Banerjee, Rahul; Fariduddin, Qazi; Nakamura, Yoko; Nomura, Kinya; Howe, Gregg A; Boland, Wilhelm; Yan, Honggao; He, Sheng Yang


    In the past decade, characterization of the host targets of pathogen virulence factors took a center stage in the study of pathogenesis and disease susceptibility in plants and humans. However, the impressive knowledge of host targets has not been broadly exploited to inhibit pathogen infection. Here, we show that host target modification could be a promising new approach to "protect" the disease-vulnerable components of plants. In particular, recent studies have identified the plant hormone jasmonate (JA) receptor as one of the common targets of virulence factors from highly evolved biotrophic/hemibiotrophic pathogens. Strains of the bacterial pathogen Pseudomonas syringae, for example, produce proteinaceous effectors, as well as a JA-mimicking toxin, coronatine (COR), to activate JA signaling as a mechanism to promote disease susceptibility. Guided by the crystal structure of the JA receptor and evolutionary clues, we succeeded in modifying the JA receptor to allow for sufficient endogenous JA signaling but greatly reduced sensitivity to COR. Transgenic Arabidopsis expressing this modified receptor not only are fertile and maintain a high level of insect defense, but also gain the ability to resist COR-producing pathogens Pseudomonas syringae pv. tomato and P. syringae pv. maculicola. Our results provide a proof-of-concept demonstration that host target modification can be a promising new approach to prevent the virulence action of highly evolved pathogens. PMID:26578782

  20. The Relationship Between Gene Polymorphism of Leptin and Leptin Receptor and Growth Hormone Deficiency.

    He, Jinshui; Fang, Yanling; Lin, Xinfu; Zhou, Huowang; Zhu, Shaobo; Zhang, Yugui; Yang, Huicong; Ye, Xiaoling


    BACKGROUND Growth hormone deficiency (GHD) is a major cause of congenital short stature. GHD patients have significantly decreased serum leptin levels, which are regulated by gene polymorphism of leptin and leptin receptor. This study thus investigated the relationship between gene polymorphism and susceptibility to GHD. MATERIAL AND METHODS A case-control study was performed using 180 GHD children in addition to 160 healthy controls. After the extraction of whole genomic DNA, the genotypes of leptin and leptin receptor gene loci were analyzed by sequencing for single-nucleotide polymorphism. RESULTS The frequency distribution of all alleles identified in leptin gene (loci rs7799039) and leptin receptor gene (loci rs1137100 and rs1137101) fit Hardy-Weinberg equilibrium. There was a significant difference in allele frequency at loci rs7799039 or rs1137101, as individuals with heterozygous GA allele had lower (rs7799039) or higher (rs1137101) GHD risk. No significant difference in allele frequency was discovered at loci rs1137100 (p>0.05), which was unrelated to GHD susceptibility. CONCLUSIONS Gene polymorphism of leptin (loci rs7799039) and leptin receptor (loci rs1137101) are correlated with GHD susceptibility. PMID:26915772

  1. Pharmacologic management of bone-related complications and bone metastases in postmenopausal women with hormone receptor-positive breast cancer

    Yardley, Denise A


    There is a high risk for bone loss and skeletal-related events, including bone metastases, in postmenopausal women with hormone receptor-positive breast cancer. Both the disease itself and its therapeutic treatments can negatively impact bone, resulting in decreases in bone mineral density and increases in bone loss. These negative effects on the bone can significantly impact morbidity and mortality. Effective management and minimization of bone-related complications in postmenopausal women with hormone receptor-positive breast cancer remain essential. This review discusses the current understanding of molecular and biological mechanisms involved in bone turnover and metastases, increased risk for bone-related complications from breast cancer and breast cancer therapy, and current and emerging treatment strategies for managing bone metastases and bone turnover in postmenopausal women with hormone receptor-positive breast cancer.

  2. Monoclonal antibodies against rabbit mammary prolactin receptors. Specific antibodies to the hormone binding domain

    Three monoclonal antibodies (M110, A82, and A917) were obtained by fusing myeloma cells and spleen cells from mice immunized with partially purified rabbit mammary gland prolactin (PRL) receptors. All 3 antibodies were capable of complete inhibition of 125I-ovine prolactin (oPRL) binding to rabbit mammary PRL receptors in either particulate or soluble form. M110 showed slightly greater potency than oPRL in competing for 125I-oPRL binding. These antibodies also inhibited PRL binding to microsomal fractions from rabbit liver, kidney, adrenal, ovary, and pig mammary gland, although A82 showed poor inhibition in pig mammary gland. There was no cross-reaction of any of the 3 monoclonal antibodies (mAbs) for the other species tested: human (T-47D breast cancer cells) and rat (liver, ovary). In order to confirm that these antibodies are specific to the binding domain, antibodies were purified, iodinated, and binding characteristics were investigated. 125I-M110 and 125I-A82 binding was completely inhibited by lactogenic hormones, whereas nonlactogenic hormones did not cross-react. Competition of 125I-M110 by oPRL was comparable to that of 125I-oPRL by unlabeled oPRL, while 125I-A917 binding was only partially competed (30-60%) by lactogenic hormones. Tissue and species specificity of labeled antibody binding paralleled results of binding inhibition experiments using 125I-oPRL. In addition, A82 and A917 completely inhibited 125I-M110 binding. In contrast, 125I-A82 binding was stimulated by A917 and 125I-A917 binding was stimulated by A82

  3. An aprotinin binding site localized in the hormone binding domain of the estrogen receptor from calf uterus.

    Nigro, V; Medici, N; Abbondanza, C; Minucci, S; Moncharmont, B; Molinari, A M; Puca, G A


    It has been proposed that the estrogen receptor bears proteolytic activity responsible for its own transformation. This activity was inhibited by aprotinin. Incubation of transformed ER with aprotinin modified the proteolytic digestion of the hormone binding subunit by proteinase K. The smallest hormone-binding fragment of the ER, obtained by tryptic digestion, was still able to bind to aprotinin. These results suggest that aprotinin interacts with ER and the hormone-binding domain of ER is endowed with a specific aprotinin-binding site. PMID:1696480

  4. The N-CoR/Histone Deacetylase 3 Complex Is Required for Repression by Thyroid Hormone Receptor

    Ishizuka, Takahiro; Lazar, Mitchell A.


    Nuclear receptor corepressors (N-CoR) and silencing mediator for retinoid and thyroid receptors (SMRT) have both been implicated in thyroid hormone receptor (TR)-mediated repression. Here we show that endogenous N-CoR, TBL1, and histone deacetylase 3 (HDAC3), but not HDAC1, -2, or -4, are recruited to a stably integrated reporter gene repressed by unliganded TR as well as the orphan receptor RevErb. Unliganded TR also recruits this complex to a transiently transfected reporter, and transcript...

  5. Requirement of tyrosine residues 333 and 338 of the growth hormone (GH) receptor for selected GH-stimulated function

    Lobie, P E; Allevato, G; Norstedt, G;


    We have examined the involvement of tyrosine residues 333 and 338 of the growth hormone (GH) receptor in the cellular response to GH. Stable Chinese hamster ovary (CHO) cell clones expressing a receptor with tyrosine residues at position 333 and 338 of the receptor substituted for phenylalanine (...... acetyltransferase cDNA expression driven by the GH-responsive region of the SPI 2.1 gene) was not affected by Y333F,Y338F substitution. Thus we provide the first experimental evidence that specific tyrosine residues of the GH receptor are required for selected cellular responses to GH....

  6. Thyroid hormone regulation of gene expression in primary cerebrocortical cells: role of thyroid hormone receptor subtypes and interactions with retinoic acid and glucocorticoids

    Gil-Ibáñez, Pilar; Bernal, Juan; Morte, Beatriz


    The effects of thyroid hormone on brain development and function are largely mediated by the binding of 3,5,3′-triiodo-L-thyronine (T3) to its nuclear receptors (TR) to regulate positively or negatively gene expression. We have analyzed by quantitative polymerase chain reaction the effect of T3 on primary cultured cells from the embryonic mouse cerebral cortex, on the expression of Hr, Klf9, Shh, Dio3, Aldh1a1, and Aldh1a3. In particular we focused on T3 receptor specificity, and on the cross...

  7. Parathyroid hormone/parathyroid hormone-related protein receptor signaling is required for maintenance of the growth plate in postnatal life

    Hirai, Takao; Chagin, Andrei S; Kobayashi, Tatsuya; Mackem, Susan; Kronenberg, Henry M.


    Parathyroid hormone (PTH)-related protein (PTHrP), regulated by Indian hedgehog and acting through the PTH/PTHrP receptor (PPR), is crucial for normal cartilage development. These observations suggest a possible role of PPR signaling in the postnatal growth plate; however, the role of PPR signaling in postnatal chondrocytes is unknown. In this study, we have generated tamoxifen-inducible and cartilage-specific PPR KO mice to evaluate the physiological role of PPR signaling in postnatal chondr...

  8. Molecular and genetic studies suggest that thyroid hormone receptor is both necessary and sufficient to mediate the developmental effects of thyroid hormone

    Das, Biswajit; Matsuda, Hiroki; Fujimoto, Kenta; Sun, Guihong; Matsuura, Kazuo; Shi, Yun-Bo


    Thyroid hormone (TH) affects diverse biological processes and can exert its effects through both gene regulation via binding the nuclear TH receptors (TRs) and non-genomic actions via binding to cell surface and cytoplasmic proteins. The critical importance of TH in vertebrate development has long been established, ranging from the formation of human cretins to the blockage of frog metamorphosis due the TH deficiency. How TH affects vertebrate development has been difficult to study in mammal...

  9. Polychlorinated biphenyls (PCBs) exert thyroid hormone-like effects in the fetal rat brain but do not bind to thyroid hormone receptors.

    Gauger, Kelly J; Kato, Yoshihisa; Haraguchi, Koichi; Lehmler, Hans-Joachim; Robertson, Larry W.; Bansal, Ruby; Zoeller, R. Thomas


    Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants routinely found in human and animal tissues. Developmental exposure to PCBs is associated with neuropsychologic deficits, which may be related to effects on thyroid hormone (TH) signaling in the developing brain. However, PCBs may interfere with TH signaling solely by reducing circulating levels of TH, or they may exert direct effects on TH receptors (TRs). Therefore, we tested whether maternal exposure to a commercial...

  10. Molecular characterization of thyroid hormone receptors from the leopard gecko, and their differential expression in the skin.

    Kanaho, Yoh-Ichiro; Endo, Daisuke; Park, Min Kyun


    Thyroid hormones (THs) play crucial roles in various developmental and physiological processes in vertebrates, including squamate reptiles. The effect of THs on shedding frequency is interesting in Squamata, since the effects on lizards are quite the reverse of those in snakes: injection of thyroxine increases shedding frequency in lizards, but decreases it in snakes. However, the mechanism underlying this differential effect remains unclear. To facilitate the investigation of the molecular mechanism of the physiological functions of THs in Squamata, their two specific receptor (TRalpha and beta) cDNAs, which are members of the nuclear hormone receptor superfamily, were cloned from a lizard, the leopard gecko, Eublepharis macularius. This is the first molecular cloning of thyroid hormone receptors (TRs) from reptiles. The deduced amino acid sequences showed high identity with those of other species, especially in the C and E/F domains, which are characteristic domains in nuclear hormone receptors. Expression analysis revealed that TRs were widely expressed in many tissues and organs, as in other animals. To analyze their role in the skin, temporal expression analysis was performed by RT-PCR, revealing that the two TRs had opposing expression patterns: TRalpha was expressed more strongly after than before skin shedding, whereas TRbeta was expressed more strongly before than after skin shedding. This provides good evidence that THs play important roles in the skin, and that the roles of their two receptor isoforms are distinct from each other. PMID:16849843