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Proteomic Analysis of Brain Region and Sex-Specific Synaptic Protein Expression in the Adult Mouse Brain. Cells 2020; 9:cells9020313. [PMID: 32012899 PMCID: PMC7072627 DOI: 10.3390/cells9020313] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 12/19/2022] Open
Abstract
Genetic disruption of synaptic proteins results in a whole variety of human neuropsychiatric disorders including intellectual disability, schizophrenia or autism spectrum disorder (ASD). In a wide range of these so-called synaptopathies a sex bias in prevalence and clinical course has been reported. Using an unbiased proteomic approach, we analyzed the proteome at the interaction site of the pre- and postsynaptic compartment, in the prefrontal cortex, hippocampus, striatum and cerebellum of male and female adult C57BL/6J mice. We were able to reveal a specific repertoire of synaptic proteins in different brain areas as it has been implied before. Additionally, we found a region-specific set of novel synaptic proteins differentially expressed between male and female individuals including the strong ASD candidates DDX3X, KMT2C, MYH10 and SET. Being the first comprehensive analysis of brain region-specific synaptic proteomes from male and female mice, our study provides crucial information on sex-specific differences in the molecular anatomy of the synapse. Our efforts should serve as a neurobiological framework to better understand the influence of sex on synapse biology in both health and disease.
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Kotarba G, Zielinska-Gorska M, Biernacka K, Gajewska A. Gonadotropin-releasing hormone-Cu complex (Cu-GnRH) transcriptional activity in vivo in the female rat anterior pituitary gland. Brain Res Bull 2020; 156:67-75. [PMID: 31931118 DOI: 10.1016/j.brainresbull.2020.01.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 12/23/2019] [Accepted: 01/03/2020] [Indexed: 12/01/2022]
Abstract
Unlike gonadotropin-releasing hormone (GnRH) analogues characterized by amino acid replacement in decapeptide primary structure, Cu-GnRH molecule preserves the native sequence but contains a Cu2+ ion stably bound to the nitrogen atoms including that of the imidazole ring of His2. Cu-GnRH can operate via cAMP/PKA signalling in anterior pituitary cells, suggesting that it may affect selected gonadotropic network gene transcription in vivo. We analysed pituitary mRNA expression of Egr-1, Nr5a1, and Lhb based on their role in luteinizing hormone (LH) synthesis; and Nos1, Adcyap1, and Prkaca due to their dependence on cAMP/PKA activity. In two independent experiments, ovariectomized rats received intracerebroventricular pulsatile (one pulse/h or two pulses/h over 5 h) microinjections of 2 nM Cu-GnRH; 2 nM antide (GnRH antagonist) + 2 nM Cu-GnRH; 100 nM PACAP6-38 (PACAP receptor antagonist) + 2 nM Cu-GnRH. Relative expression of selected mRNAs was determined by qRT-PCR. LH serum concentration was examined according to RIA. All examined genes responded to Cu-GnRH stimulation with increased transcriptional activity in a manner dependent on pulse frequency pattern. Increased expression of Nr5a1, Lhb, Nos1, Adcyap1, and Prkaca mRNA was observed solely in rats receiving the complex with frequency of two pulses/h over 5 h. Egr-1 transcription was up-regulated for both applied Cu-GnRH pulsatile patterns. The stimulatory effect of Cu-GnRH on gene transcription was dependent on both GnRH receptor and PAC-1 activation. In conclusion, obtained results indicate that Cu-GnRH complex is a GnRH analogue able to induce both IP3/PKC and cAMP/PKA-dependent gonadotrope network gene transcription in vivo.
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Affiliation(s)
- Grzegorz Kotarba
- Department of Animal Physiology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 3 Instytucka St., 05-110 Jablonna, Poland.
| | - Marlena Zielinska-Gorska
- Department of Animal Physiology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 3 Instytucka St., 05-110 Jablonna, Poland.
| | - Katarzyna Biernacka
- Department of Animal Physiology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 3 Instytucka St., 05-110 Jablonna, Poland
| | - Alina Gajewska
- Department of Animal Physiology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 3 Instytucka St., 05-110 Jablonna, Poland.
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3
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Murányi J, Varga A, Gyulavári P, Pénzes K, Németh CE, Csala M, Pethő L, Csámpai A, Halmos G, Peták I, Vályi-Nagy I. Novel Crizotinib-GnRH Conjugates Revealed the Significance of Lysosomal Trapping in GnRH-Based Drug Delivery Systems. Int J Mol Sci 2019; 20:ijms20225590. [PMID: 31717403 PMCID: PMC6888004 DOI: 10.3390/ijms20225590] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 11/06/2019] [Indexed: 12/11/2022] Open
Abstract
Several promising anti-cancer drug–GnRH (gonadotropin-releasing hormone) conjugates have been developed in the last two decades, although none of them have been approved for clinical use yet. Crizotinib is an effective multi-target kinase inhibitor, approved against anaplastic lymphoma kinase (ALK)- or ROS proto-oncogene 1 (ROS-1)-positive non-small cell lung carcinoma (NSCLC); however, its application is accompanied by serious side effects. In order to deliver crizotinib selectively into the tumor cells, we synthesized novel crizotinib analogues and conjugated them to a [d-Lys6]–GnRH-I targeting peptide. Our most prominent crizotinib–GnRH conjugates, the amide-bond-containing [d-Lys6(crizotinib*)]–GnRH-I and the ester-bond-containing [d-Lys6(MJ55*)]–GnRH-I, were able to bind to GnRH-receptor (GnRHR) and exert a potent c-Met kinase inhibitory effect. The efficacy of compounds was tested on the MET-amplified and GnRHR-expressing EBC-1 NSCLC cells. In vitro pharmacological profiling led to the conclusion that that crizotinib–GnRH conjugates are transported directly into lysosomes, where the membrane permeability of crizotinib is diminished. As a consequence of GnRHR-mediated endocytosis, GnRH-conjugated crizotinib bypasses its molecular targets—the ATP-binding site of RTKs— and is sequestered in the lysosomes. These results explained the lower efficacy of crizotinib–GnRH conjugates in EBC-1 cells, and led to the conclusion that drug escape from the lysosomes is a major challenge in the development of clinically relevant anti-cancer drug–GnRH conjugates.
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Affiliation(s)
- József Murányi
- MTA-SE Pathobiochemistry Research Group, Tűzoltó St. 37-47, H1094 Budapest, Hungary; (A.V.); (P.G.); (K.P.)
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, H1094 Budapest, Hungary; (C.E.N.); (M.C.)
- Correspondence:
| | - Attila Varga
- MTA-SE Pathobiochemistry Research Group, Tűzoltó St. 37-47, H1094 Budapest, Hungary; (A.V.); (P.G.); (K.P.)
| | - Pál Gyulavári
- MTA-SE Pathobiochemistry Research Group, Tűzoltó St. 37-47, H1094 Budapest, Hungary; (A.V.); (P.G.); (K.P.)
| | - Kinga Pénzes
- MTA-SE Pathobiochemistry Research Group, Tűzoltó St. 37-47, H1094 Budapest, Hungary; (A.V.); (P.G.); (K.P.)
| | - Csilla E. Németh
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, H1094 Budapest, Hungary; (C.E.N.); (M.C.)
| | - Miklós Csala
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, H1094 Budapest, Hungary; (C.E.N.); (M.C.)
| | - Lilla Pethő
- MTA-ELTE Research Group of Peptide Chemistry, Eötvös Loránd University, H1117 Budapest, Hungary
| | - Antal Csámpai
- Institute of Chemistry, Eötvös Loránd University, H1117 Budapest, Hungary;
| | - Gábor Halmos
- Department of Biopharmacy, Faculty of Pharmacy, University of Debrecen, H4032 Debrecen, Hungary;
| | - István Peták
- Oncompass Medicine Hungary Ltd., H1024 Budapest, Hungary;
| | - István Vályi-Nagy
- Central Hospital of Southern Pest National Institute of Hematology and Infectious Diseases, H1097 Budapest, Hungary;
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GnRH Antagonists Produce Differential Modulation of the Signaling Pathways Mediated by GnRH Receptors. Int J Mol Sci 2019; 20:ijms20225548. [PMID: 31703269 PMCID: PMC6888270 DOI: 10.3390/ijms20225548] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/29/2019] [Accepted: 11/04/2019] [Indexed: 12/13/2022] Open
Abstract
Commercial gonadotropin-releasing hormone (GnRH) antagonists differ by 1-2 amino acids and are used to inhibit gonadotropin production during assisted reproduction technologies (ART). In this study, potencies of three GnRH antagonists, Cetrorelix, Ganirelix and Teverelix, in inhibiting GnRH-mediated intracellular signaling, were compared in vitro. GnRH receptor (GnRHR)-transfected HEK293 and neuroblastoma-derived SH-SY5Y cell lines, as well as mouse pituitary LβT2 cells endogenously expressing the murine GnRHR, were treated with GnRH in the presence or absence of the antagonist. We evaluated intracellular calcium (Ca2+) and cAMP increases, cAMP-responsive element binding-protein (CREB) and extracellular-regulated kinase 1 and 2 (ERK1/2) phosphorylation, β-catenin activation and mouse luteinizing-hormone β-encoding gene (Lhb) transcription by bioluminescence resonance energy transfer (BRET), Western blotting, immunostaining and real-time PCR as appropriate. The kinetics of GnRH-induced Ca2+ rapid increase revealed dose-response accumulation with potency (EC50) of 23 nM in transfected HEK293 cells, transfected SH-SY5Y and LβT2 cells. Cetrorelix inhibited the 3 × EC50 GnRH-activated calcium signaling at concentrations of 1 nM-1 µM, demonstrating higher potency than Ganirelix and Teverelix, whose inhibitory doses fell within the 100 nM-1 µM range in both transfected HEK293 and SH-SY5Y cells in vitro. In transfected SH-SY5Y, Cetrorelix was also significantly more potent than other antagonists in reducing GnRH-mediated cAMP accumulation. All antagonists inhibited pERK1/2 and pCREB activation at similar doses, in LβT2 and transfected HEK293 cells treated with 100 nM GnRH. Although immunostainings suggested that Teverelix could be less effective than Cetrorelix and Ganirelix in inhibiting 1 µM GnRH-induced β-catenin activation, Lhb gene expression increase occurring upon LβT2 cell treatment by 1 µM GnRH was similarly inhibited by all antagonists. To conclude, this study has demonstrated Cetrorelix-, Ganirelix- and Teverelix-specific biased effects at the intracellular level, not affecting the efficacy of antagonists in inhibiting Lhb gene transcription.
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Avet C, Denoyelle C, L'Hôte D, Petit F, Guigon CJ, Cohen-Tannoudji J, Simon V. GnRH regulates the expression of its receptor accessory protein SET in pituitary gonadotropes. PLoS One 2018; 13:e0201494. [PMID: 30052687 PMCID: PMC6063425 DOI: 10.1371/journal.pone.0201494] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 07/16/2018] [Indexed: 01/26/2023] Open
Abstract
Reproductive function is under the control of the neurohormone GnRH, which activates a G-protein-coupled receptor (GnRHR) expressed in pituitary gonadotrope cells. GnRHR activates a complex signaling network to regulate synthesis and secretion of the two gonadotropin hormones, luteinizing hormone and follicle-stimulating hormone, both regulating gametogenesis and steroidogenesis in gonads. Recently, in an attempt to identify the mechanisms underlying GnRHR signaling plasticity, we identified the first interacting partner of GnRHR, the proto-oncogene SET. We showed that SET binds to intracellular domains of GnRHR to enhance its coupling to cAMP pathway in αT3-1 gonadotrope cells. Here, we demonstrate that SET protein is rapidly regulated by GnRH, which increases SET phosphorylation state and decreases dose-dependently SET protein level. Our results highlight a post-translational regulation of SET protein involving the proteasome pathway. We determined that SET phosphorylation upon GnRH stimulation is mediated by PKC and that PKC mediates GnRH-induced SET down-regulation. Phosphorylation on serine 9 targets SET for degradation into the proteasome. Furthermore, a non-phosphorylatable SET mutant on serine 9 is resistant to GnRH-induced down-regulation. Altogether, these data suggest that GnRH-induced SET phosphorylation on serine 9 mediates SET protein down-regulation through the proteasome pathway. Noteworthy, SET down-regulation was also observed in response to pulsatile GnRH stimulation in LβT2 gonadotrope cells as well as in vivo in prepubertal female mice supporting its physiological relevance. In conclusion, this study highlights a regulation of SET protein by the neurohormone GnRH and identifies some of the mechanisms involved.
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Affiliation(s)
- Charlotte Avet
- Sorbonne Paris Cité, Université Paris-Diderot, CNRS UMR 8251, INSERM U1133, Biologie Fonctionnelle et Adaptative, Physiologie de l'axe gonadotrope, Paris, France
| | - Chantal Denoyelle
- Sorbonne Paris Cité, Université Paris-Diderot, CNRS UMR 8251, INSERM U1133, Biologie Fonctionnelle et Adaptative, Physiologie de l'axe gonadotrope, Paris, France
| | - David L'Hôte
- Sorbonne Paris Cité, Université Paris-Diderot, CNRS UMR 8251, INSERM U1133, Biologie Fonctionnelle et Adaptative, Physiologie de l'axe gonadotrope, Paris, France
| | - Florence Petit
- Sorbonne Paris Cité, Université Paris-Diderot, CNRS UMR 8251, INSERM U1133, Biologie Fonctionnelle et Adaptative, Physiologie de l'axe gonadotrope, Paris, France
| | - Céline J Guigon
- Sorbonne Paris Cité, Université Paris-Diderot, CNRS UMR 8251, INSERM U1133, Biologie Fonctionnelle et Adaptative, Physiologie de l'axe gonadotrope, Paris, France
| | - Joëlle Cohen-Tannoudji
- Sorbonne Paris Cité, Université Paris-Diderot, CNRS UMR 8251, INSERM U1133, Biologie Fonctionnelle et Adaptative, Physiologie de l'axe gonadotrope, Paris, France
| | - Violaine Simon
- Sorbonne Paris Cité, Université Paris-Diderot, CNRS UMR 8251, INSERM U1133, Biologie Fonctionnelle et Adaptative, Physiologie de l'axe gonadotrope, Paris, France
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Chang JP, Pemberton JG. Comparative aspects of GnRH-Stimulated signal transduction in the vertebrate pituitary - Contributions from teleost model systems. Mol Cell Endocrinol 2018; 463:142-167. [PMID: 28587765 DOI: 10.1016/j.mce.2017.06.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/31/2017] [Accepted: 06/01/2017] [Indexed: 02/07/2023]
Abstract
Gonadotropin-releasing hormone (GnRH) is a major regulator of reproduction through actions on pituitary gonadotropin release and synthesis. Although it is often thought that pituitary cells are exposed to only one GnRH, multiple GnRH forms are delivered to the pituitary of teleost fishes; interestingly this can include the cGnRH-II form usually thought to be non-hypophysiotropic. GnRHs can regulate other pituitary cell-types, both directly as well as indirectly, and multiple GnRH receptors (GnRHRs) may also be expressed in the pituitary, and even within a single pituitary cell-type. Literature on the differential actions of native GnRH isoforms in primary pituitary cells is largely derived from teleost fishes. This review will outline the diversity and complexity of GnRH-GnRHR signal transduction found within vertebrate gonadotropes as well as extra-gonadotropic sites with special emphasis on comparative studies from fish models. The implications that GnRHR transduction mechanisms are GnRH isoform-, function-, and cell-specific are also discussed.
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Affiliation(s)
- John P Chang
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
| | - Joshua G Pemberton
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
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7
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Stamatiades GA, Kaiser UB. Gonadotropin regulation by pulsatile GnRH: Signaling and gene expression. Mol Cell Endocrinol 2018; 463:131-141. [PMID: 29102564 PMCID: PMC5812824 DOI: 10.1016/j.mce.2017.10.015] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/27/2017] [Accepted: 10/27/2017] [Indexed: 12/12/2022]
Abstract
The precise orchestration of hormonal regulation at all levels of the hypothalamic-pituitary-gonadal axis is essential for normal reproductive function and fertility. The pulsatile secretion of hypothalamic gonadotropin-releasing hormone (GnRH) stimulates the synthesis and release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) by pituitary gonadotropes. GnRH acts by binding to its high affinity seven-transmembrane receptor (GnRHR) on the cell surface of anterior pituitary gonadotropes. Different signaling cascades and transcriptional mechanisms are activated, depending on the variation in GnRH pulse frequency, to stimulate the synthesis and release of FSH and LH. While changes in GnRH pulse frequency may explain some of the differential regulation of FSH and LH, other factors, such as activin, inhibin and sex steroids, also contribute to gonadotropin production. In this review, we focus on the transcriptional regulation of the gonadotropin subunit genes and the signaling pathways activated by pulsatile GnRH.
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Affiliation(s)
- George A Stamatiades
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, United States
| | - Ursula B Kaiser
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, United States.
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8
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Liu H, Gu Y, Wang H, Yin J, Zheng G, Zhang Z, Lu M, Wang C, He Z. Overexpression of PP2A inhibitor SET oncoprotein is associated with tumor progression and poor prognosis in human non-small cell lung cancer. Oncotarget 2016; 6:14913-25. [PMID: 25945834 PMCID: PMC4558125 DOI: 10.18632/oncotarget.3818] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 03/29/2015] [Indexed: 01/09/2023] Open
Abstract
SET oncoprotein is an endogenous inhibitor of protein phosphatase 2A (PP2A), and SET-mediated PP2A inhibition is an important regulatory mechanism for promoting cancer initiation and progression of several types of human leukemia disease. However, its potential relevance in solid tumors as non-small cell lung cancer (NSCLC) remains mostly unknown. In this study, we showed that SET was evidently overexpressed in human NSCLC cell lines and NSCLC tissues. Clinicopathologic analysis showed that SET expression was significantly correlated with clinical stage (p < 0.001), and lymph node metastasis (p < 0.05). Kaplan-Meier analysis revealed that patients with high SET expression had poorer overall survival rates than those with low SET expression. Moreover, knockdown of SET in NSCLC cells resulted in attenuated proliferative and invasive abilities. The biological effect of SET on proliferation and invasion was mediated by the inhibition of the PP2A, which in turn, activation of AKT and ERK, increased the expression of cyclin D1 and MMP9, and decreased the expression of p27. Furthermore, we observed that restoration of PP2A using SET antagonist FTY720 impaired proliferative and invasive potential in vitro, as well as inhibited tumor growth in vivo of NSCLC cells. Taken together, SET oncoprotein plays an important role in NSCLC progression, which could serve as a potential prognosis marker and a novel therapeutic target for NSCLC patients.
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Affiliation(s)
- Hao Liu
- Cancer Hospital and Cancer Research Institute, Guangzhou Medical University, Guangzhou, PR China
| | - Yixue Gu
- Cancer Hospital and Cancer Research Institute, Guangzhou Medical University, Guangzhou, PR China
| | - Hongsheng Wang
- Department of Microbial and Biochemical Pharmacy, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, PR China
| | - Jiang Yin
- Cancer Hospital and Cancer Research Institute, Guangzhou Medical University, Guangzhou, PR China
| | - Guopei Zheng
- Cancer Hospital and Cancer Research Institute, Guangzhou Medical University, Guangzhou, PR China
| | - Zhijie Zhang
- Cancer Hospital and Cancer Research Institute, Guangzhou Medical University, Guangzhou, PR China
| | - Minyin Lu
- Cancer Hospital and Cancer Research Institute, Guangzhou Medical University, Guangzhou, PR China
| | - Chenkun Wang
- Cancer Hospital and Cancer Research Institute, Guangzhou Medical University, Guangzhou, PR China
| | - Zhimin He
- Cancer Hospital and Cancer Research Institute, Guangzhou Medical University, Guangzhou, PR China
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9
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Gajewska A, Zielinska-Gorska M, Wolinska-Witort E, Siawrys G, Baran M, Kotarba G, Biernacka K. Intracellular mechanisms involved in copper-gonadotropin-releasing hormone (Cu-GnRH) complex-induced cAMP/PKA signaling in female rat anterior pituitary cells in vitro. Brain Res Bull 2015; 120:75-82. [PMID: 26551063 DOI: 10.1016/j.brainresbull.2015.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 10/31/2015] [Accepted: 11/03/2015] [Indexed: 01/24/2023]
Abstract
The copper-gonadotropin-releasing hormone molecule (Cu-GnRH) is a GnRH analog, which preserves its amino acid sequence, but which contains a Cu(2+) ion stably bound to the nitrogen atoms including that of the imidazole ring of Histidine(2). A previous report indicated that Cu-GnRH was able to activate cAMP/PKA signaling in anterior pituitary cells in vitro, but raised the question of which intracellular mechanism(s) mediated the Cu-GnRH-induced cAMP synthesis in gonadotropes. To investigate this mechanism, in the present study, female rat anterior pituitary cells in vitro were pretreated with 0.1 μM antide, a GnRH antagonist; 0.1 μM cetrorelix, a GnRH receptor antagonist; 0.1 μM PACAP6-38, a PAC-1 receptor antagonist; 2 μM GF109203X, a protein kinase C inhibitor; 50 mM PMA, a protein kinase C activator; the protein kinase A inhibitors H89 (30 μM) and KT5720 (60 nM); factors affecting intracellular calcium activity: 2.5 mM EGTA; 2 μM thapsigargin; 5 μM A23187, a Ca(2+) ionophore; or 10 μg/ml cycloheximide, a protein synthesis inhibitor. After one of the above pretreatments, cells were incubated in the presence of 0.1 μM Cu-GnRH for 0.5, 1, and 3 h. Radioimmunoassay analysis of cAMP confirmed the functional link between Cu-GnRH stimulation and cAMP/PKA signal transduction in rat anterior pituitary cells, demonstrating increased intracellular cAMP, which was reduced in the presence of specific PKA inhibitors. The stimulatory effect of Cu-GnRH on cAMP production was partly dependent on GnRH receptor activation. In addition, an indirect and Ca(2+)-dependent mechanism might be involved in intracellular adenylate cyclase stimulation. Neither activation of protein kinase C nor new protein synthesis was involved in the Cu-GnRH-induced increase of cAMP in the rat anterior pituitary primary cultures. Presented data indicate that conformational changes of GnRH molecule resulting from cooper ion coordination affect specific pharmacological properties of Cu-GnRH molecule including specific pattern of intracellular activity induced by complex in anterior pituitary cells in vitro.
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Affiliation(s)
- Alina Gajewska
- Department of Neuroendocrinology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jablonna n. Warsaw, Poland.
| | - Marlena Zielinska-Gorska
- Department of Neuroendocrinology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jablonna n. Warsaw, Poland
| | - Ewa Wolinska-Witort
- Neuroendocrinology Department, Medical Centre for Postgraduate Education, Marymoncka 99/103 st., 01-813 Warsaw, Poland
| | - Gabriela Siawrys
- Department of Animal Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A st. 10-719 Olsztyn, Poland
| | - Marta Baran
- Department of Neuroendocrinology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jablonna n. Warsaw, Poland
| | - Grzegorz Kotarba
- Department of Neuroendocrinology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jablonna n. Warsaw, Poland
| | - Katarzyna Biernacka
- Department of Neuroendocrinology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jablonna n. Warsaw, Poland
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10
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Berkovits BD, Mayr C. Alternative 3' UTRs act as scaffolds to regulate membrane protein localization. Nature 2015; 522:363-7. [PMID: 25896326 PMCID: PMC4697748 DOI: 10.1038/nature14321] [Citation(s) in RCA: 333] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 02/10/2015] [Indexed: 12/24/2022]
Abstract
About half of human genes use alternative cleavage and polyadenylation (ApA) to generate mRNA transcripts that differ in the length of their 3' untranslated regions (3'UTRs) while producing the same protein 1–3. Here we show in human cell lines that alternative 3' UTRs differentially regulate the localization of membrane proteins. The long 3'UTR of CD47 enables efficient cell surface expression of CD47 protein, whereas the short 3'UTR primarily localizes CD47 protein to the endoplasmic reticulum. CD47 protein localization occurs post-translationally and independently of RNA localization. In our model of 3' UTR-dependent protein localization, the long 3' UTR of CD47 acts as a scaffold to recruit a protein complex containing the RNA-binding protein HuR (also known as ELAVL1) and SET4 to the site of translation. This facilitates interaction of SET with the newly translated cytoplasmic domains of CD47 and results in subsequent translocation of CD47 to the plasma membrane via activated RAC1 5. We also show that CD47 protein has different functions depending on whether it was generated by the short or long 3'UTR isoforms. Thus, ApA contributes to the functional diversity of the proteome without changing the amino acid sequence. 3' UTR-dependent protein localization has the potential to be a widespread trafficking mechanism for membrane proteins because HuR binds to thousands of mRNAs6–9, and we show that the long 3' UTRs of CD44, ITGA1 and TNFRSF13C, which are bound by HuR, increase surface protein expression compared to their corresponding short 3' UTRs. We propose that during translation the scaffold function of 3' UTRs facilitates binding of proteins to nascent proteins to direct their transport or function—and that this role of 3' UTRs can be regulated by ApA.
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Affiliation(s)
- Binyamin D Berkovits
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, 1275 York Ave, New York, New York 10065, USA
| | - Christine Mayr
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, 1275 York Ave, New York, New York 10065, USA
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11
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Perrett RM, McArdle CA. Molecular mechanisms of gonadotropin-releasing hormone signaling: integrating cyclic nucleotides into the network. Front Endocrinol (Lausanne) 2013; 4:180. [PMID: 24312080 PMCID: PMC3834291 DOI: 10.3389/fendo.2013.00180] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 11/06/2013] [Indexed: 01/21/2023] Open
Abstract
Gonadotropin-releasing hormone (GnRH) is the primary regulator of mammalian reproductive function in both males and females. It acts via G-protein coupled receptors on gonadotropes to stimulate synthesis and secretion of the gonadotropin hormones luteinizing hormone and follicle-stimulating hormone. These receptors couple primarily via G-proteins of the Gq/ll family, driving activation of phospholipases C and mediating GnRH effects on gonadotropin synthesis and secretion. There is also good evidence that GnRH causes activation of other heterotrimeric G-proteins (Gs and Gi) with consequent effects on cyclic AMP production, as well as for effects on the soluble and particulate guanylyl cyclases that generate cGMP. Here we provide an overview of these pathways. We emphasize mechanisms underpinning pulsatile hormone signaling and the possible interplay of GnRH and autocrine or paracrine regulatory mechanisms in control of cyclic nucleotide signaling.
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Affiliation(s)
- Rebecca M. Perrett
- Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, Bristol, UK
| | - Craig A. McArdle
- Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, Bristol, UK
- *Correspondence: Craig A. McArdle, Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, 1 Whitson Street, Bristol BS1 3NY, UK e-mail:
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