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Menon KMJ, Menon B. Structure, function and regulation of gonadotropin receptors - a perspective. Mol Cell Endocrinol 2012; 356:88-97. [PMID: 22342845 PMCID: PMC3327826 DOI: 10.1016/j.mce.2012.01.021] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 01/13/2012] [Accepted: 01/24/2012] [Indexed: 11/19/2022]
Abstract
Luteinizing hormone receptor and follicle stimulating hormone receptor play a crucial role in female and male reproduction. Significant new information has emerged about the structure, mechanism of activation, and regulation of expression of these receptors. Here we provide an overview of the current information on those aspects with an in-depth discussion of the recent developments in the post-transcriptional mechanism of LH receptor expression mediated by a specific LH receptor mRNA binding protein, designated as LRBP. LRBP was identified by electrophoretic gel mobility shift assay using cytosolic fractions from ovaries in the down regulated state. LRBP was purified, its binding site on LH receptor mRNA was identified and characterized. During ligand-induced down regulation, LRBP expression is increased through the cAMP/PKA and ERK signaling pathway, is translocated to translating ribosomes, binds LH receptor mRNA and forms an untranslatable ribonucleoprotein complex. This complex is then routed to the mRNA degradation machinery resulting in diminished levels of both LHR mRNA and cell surface expression of LH receptor. The studies leading to these conclusions are presented.
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Affiliation(s)
- K M J Menon
- Departments of Obstetrics/Gynecology and Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109-0617, United States.
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Rocha A, Gómez A, Zanuy S, Cerdá-Reverter JM, Carrillo M. Molecular characterization of two sea bass gonadotropin receptors: cDNA cloning, expression analysis, and functional activity. Mol Cell Endocrinol 2007; 272:63-76. [PMID: 17543442 DOI: 10.1016/j.mce.2007.04.007] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Revised: 04/19/2007] [Accepted: 04/21/2007] [Indexed: 10/23/2022]
Abstract
The follicle-stimulating hormone (FSH) and the luteinizing hormone (LH) play central roles in vertebrate reproduction. They act through their cognate receptors to stimulate testicular and ovarian functions. The present study reports the cloning and characterization of two sea bass (Dicentrarchus labrax) cDNAs encoding a FSH receptor (sbsFSHR) and a LH receptor (sbsLHR). The mature proteins display typical features of the glycoprotein hormone receptor family members, but the sbsFSHR also contains some remarkable differences when compared with other fish or mammalian FSHRs. Among them, a distinct extracellular N-terminal cysteine domain as regards to its length and cysteine number, and the presence of an extra leucine-rich repeat. Expression analysis revealed that the sbsFSHR is exclusively expressed in gonadal tissues, specifically in the follicular wall of previtellogenic and early-vitellogenic follicles. On the contrary, sbsLHR mRNA was found to be widely distributed in sea bass somatic tissues. When stably expressed in mammalian cell lines, sbsFSHR was specifically stimulated by bovine FSH, while sbsLHR was activated by both bovine LH and FSH. Nevertheless, specific stimulation of the sbsLHR was observed when recombinant sea bass gonadotropins were used. The isolation of a FSHR and a LHR in sea bass opens new ways to study gonadotropin action in this species.
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Affiliation(s)
- Ana Rocha
- Department of Fish Physiology and Biotechnology, Instituto de Acuicultura de Torre la Sal, Consejo Superior de Investigaciones Cientificas, 12595 Torre la Sal, Ribera de Cabanes, Castellón, Spain
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Moyle WR, Xing Y, Lin W, Cao D, Myers RV, Kerrigan JE, Bernard MP. Model of Glycoprotein Hormone Receptor Ligand Binding and Signaling. J Biol Chem 2004; 279:44442-59. [PMID: 15304493 DOI: 10.1074/jbc.m406948200] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Studies described here were initiated to develop a model of glycoprotein hormone receptor structure and function. We found that the region that links the lutropin receptor leucine-rich repeat domain (LRD) to its transmembrane domain (TMD) has substantial roles in ligand binding and signaling, hence we term it the signaling specificity domain (SSD). Theoretical considerations indicated the short SSDs in marmoset lutropin and salmon follitropin receptors have KH domain folds. We assembled models of lutropin, follitropin, and thyrotropin receptors by aligning models of their LRD, TMD, and shortened SSD in a manner that explains how substitutions in follitropin and thyrotropin receptors distant from their apparent ligand binding sites enable them to recognize lutropins. In these models, the SSD is parallel to the concave surface of the LRD and makes extensive contacts with TMD outer loops 1 and 2. The LRD appears to contact TMD outer loop 3 and a few residues in helices 1, 5, 6, and 7. We propose that signaling results from contacts of the ligands with the SSD and LRD that alter the LRD, which then moves TMD helices 6 and 7. The positions of the LRD and SSD support the notion that the receptor can be activated by hormones that dock with these domains in either of two different orientations. This would account for the abilities of some ligands and ligand chimeras to bind multiple receptors and for some receptors to bind multiple ligands. This property of the receptor may have contributed significantly to ligand-receptor co-evolution.
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Affiliation(s)
- William R Moyle
- Department of OB-GYN, Robert Wood Johnson (Rutgers) Medical School, Piscataway, New Jersey 08854, USA.
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Saint-Dizier M, Chopineau M, Dupont J, Combarnous Y. Expression of the full-length and alternatively spliced equine luteinizing hormone/chorionic gonadotropin receptor mRNAs in the primary corpus luteum and fetal gonads during pregnancy. Reproduction 2004; 128:219-28. [PMID: 15280561 DOI: 10.1530/rep.1.00164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The full-length equine luteinizing hormone/chorionic gonadotropin (LH/CG) receptor (eLH/CG-RA) cDNA and two alternatively spliced isoforms (eLH/CG-RB,C) were isolated from luteal tissue and characterized using a combination of reverse transcription-polymerase chain reaction (RT-PCR) and 5'-rapid amplification of cDNA ends. The 680-amino acid full sequence of eLH/CG-RA displayed 87-92% homology with other mammalian LH/CG-Rs. The eLH/CG-RB and eLH/CG-RC cDNA isoforms were truncated from the 3'-end of exon X: eLH/CG-RB spliced out of frame into the last exon whereas eLH/CG-RC contained an in-frame stop codon within a divergent sequence. Consequently, both eLH/CG-RB and eLH/CG-RC cDNA isoforms encoded putative proteins without transmembrane and intracellular domains. In order to study the responsiveness of the primary corpus luteum (CL) and fetal gonads to eCG, the expression of eLH/CG-R mRNAs was examined by RT-PCR and Northern blot analysis during early and mid-pregnancy. All three eLH/CG-R cDNA isoforms (eLH/CG-RA,B,C) were expressed from day 14 to day 83 of pregnancy in the primary CL and from day 44 to day 222 in fetal gonads. Interestingly, the primary CL at days 89 and 151 expressed only truncated eLH/CG-R cDNA isoforms. The relative values of Northern hybridized major 7, 5.7, 3.9 and 1.8 kb eLH/CG-R mRNA transcripts tended to decrease in the primary CL whereas the unique major 1.8 kb eLH/CG-R mRNA was steadily expressed in fetal gonads during pregnancy. These results show that the expression of eLH/CG-R mRNAs occurs in the fetal gonads before ceasing in the primary CL and suggest that eCG may be involved in the gradual transition from a luteal to a feto-placental output of steroids during equine pregnancy.
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Affiliation(s)
- Marie Saint-Dizier
- Unité de Physiologie de la Reproduction et des Comportements, UMR 6175 INRA-CNRS-Université F. Rabelais de Tours-Haras Nationaux, 37 380 Nouzilly, France.
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Bukovsky A, Indrapichate K, Fujiwara H, Cekanova M, Ayala ME, Dominguez R, Caudle MR, Wimalsena J, Elder RF, Copas P, Foster JS, Fernando RI, Henley DC, Upadhyaya NB. Multiple luteinizing hormone receptor (LHR) protein variants, interspecies reactivity of anti-LHR mAb clone 3B5, subcellular localization of LHR in human placenta, pelvic floor and brain, and possible role for LHR in the development of abnormal pregnancy, pelvic floor disorders and Alzheimer's disease. Reprod Biol Endocrinol 2003; 1:46. [PMID: 12816543 PMCID: PMC161821 DOI: 10.1186/1477-7827-1-46] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2003] [Accepted: 06/03/2003] [Indexed: 11/10/2022] Open
Abstract
Distinct luteinizing hormone receptor (LHR) protein variants exist due to the posttranslational modifications. Besides ovaries, LHR immunoreactivity (LHRI) was also found in other tissues, such as the brain, fallopian tube, endometrium, trophoblast and resident tissue macrophages. The 3B5 mouse monoclonal antibody was raised against purified rat LHR. In rat, porcine and human ovaries, the 3B5 identified six distinct LHR bands migrating at approximately 92, 80, 68, 59, 52 and 48 kDa. Characteristic LHRI was detected in rat, human and porcine corpora lutea. During cellular differentiation, subcellular LHR distribution changed from none to granular cytoplasmic, perinuclear, surface, nuclear and no staining. There were also differences in vascular LHR expression--lack of LHRI in ovarian vessels and strong staining of vessels in other tissues investigated. In normal human term placentae, villous LHRI was associated with blood sinusoids and cytotrophoblast cells, and rarely detected in trophoblastic syncytium. In all abnormal placentae, the LHRI of sinusoids was absent, and syncytium showed either enhanced (immature placental phenotypes) or no LHRI (aged placental phenotype). LHRI in human brain was identified in microglial cells (CD68+ resident macrophages). Protein extracts from human vaginal wall and levator ani muscle and fascia showed strong approximately 92 and 68 kDa species, and LHRI was detected in smooth muscle cells, fibroblasts, resident macrophages and nuclei of skeletal muscle fibers. Our observations indicate that, in contrast to the theory on the role of vascular hormone receptors in preferential pick up of circulating hormones, there is no need to enhance selective pick up rather only prevent LH/CG transport to inappropriate sites. Abnormal placental LHR expression may play a role in the development of abnormal pregnancy. Expression of LHR in the pelvic floor compartments suggests that high LH levels in postmenopausal women may contribute to the pelvic floor relaxation and increased incidence of pelvic floor disorders. Since chorionic gonadotropin increases secretion of a variety of cytokines by monocytes, and induces their inflammatory reaction and phagocytic activity, high LH levels in aging individuals may also activate microglia (mononuclear phagocyte system in the central nervous system) and contribute to the development of Alzheimer's disease and other inflammation-mediated neurodegenerative diseases.
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Affiliation(s)
- Antonin Bukovsky
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
| | - Korakod Indrapichate
- School of Biology, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - Hiroshi Fujiwara
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, Sakyoku, Kyoto 60601, Japan
| | - Maria Cekanova
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
| | - Maria E Ayala
- Laboratory of Biology of Reproduction, Facultad de Estudios Profesionales Zaragoza, UNAM, Mexico D.F., Mexico
| | - Roberto Dominguez
- Laboratory of Biology of Reproduction, Facultad de Estudios Profesionales Zaragoza, UNAM, Mexico D.F., Mexico
| | - Michael R Caudle
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
| | - Jay Wimalsena
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
| | - Robert F Elder
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
| | - Pleas Copas
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
| | - James S Foster
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
| | - Romaine I Fernando
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
| | - Donald C Henley
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
| | - Nirmala B Upadhyaya
- Laboratory for Development, Differentiation and Cancer, Department of Obstetrics and Gynecology, The University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN, 37920, USA
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Bozon V, Couture L, Pajot-Augy E, Richard F, Remy JJ, Salesse R. Rescue of intracellularly trapped lutropin receptor exodomain by endodomain and reconstitution of a functional membrane receptor: interaction between exo- and endodomains. Protein Expr Purif 2002; 25:114-23. [PMID: 12071706 DOI: 10.1006/prep.2002.1617] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The lutropin receptor consists of an extracellular N-terminal half and a membrane-associated C-terminal half. hCG initially binds the exodomain with a high affinity and the resulting complex is thought to interact with the endodomain through a secondary contact generating a hormonal signal. Therefore, the exodomain and endodomain are likely to associate directly or indirectly with each other, but lack of fruitful materials and technology has hampered knowledge about their physical relationship and contact sites. In this work, we engineered a double-recombinant (separate exodomain and endodomain) baculovirus system successfully expressing on the surface of insect cells high levels of split LH receptor, binding the hormone with high affinity and inducing cAMP synthesis. In contrast, the exodomain and endodomain expressed separately were mostly trapped in cells. Our data indicate that the exodomain and endodomain are disulfide linked in the split receptor. When the disulfide links were reduced, the split receptor still induced cAMP up to 60%, which raises the intriguing possibility of a residual induction activity of the endodomain in the absence of high-affinity ligand binding. Our results also underscore that the targeting and transport of the LH receptor to plasma membrane require both domains, whereas each domain is independently sufficient for folding. The expression level of functional lutropin receptors is the highest ever reported. Our system may also be useful for future studies requiring a high amount of soluble secreted exodomain.
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Affiliation(s)
- Véronique Bozon
- Laboratoire de Physiologie des Cellules Cardiaques et Vasculaires, CNRS-UMR 6542, Tours, France
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Current literature in mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2000; 35:1148-1155. [PMID: 11006610 DOI: 10.1002/1096-9888(200009)35:9<1148::aid-jms982>3.0.co;2-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of mass spectrometry. Each bibliography is divided into 11 sections: 1 Books, Reviews & Symposia; 2 Instrumental Techniques & Methods; 3 Gas Phase Ion Chemistry; 4 Biology/Biochemistry: Amino Acids, Peptides & Proteins; Carbohydrates; Lipids; Nucleic Acids; 5 Pharmacology/Toxicology; 6 Natural Products; 7 Analysis of Organic Compounds; 8 Analysis of Inorganics/Organometallics; 9 Surface Analysis; 10 Environmental Analysis; 11 Elemental Analysis. Within each section, articles are listed in alphabetical order with respect to author (3 Weeks journals - Search completed at 28th. June 2000)
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