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Xu Y, Li W, Shi M, Xu X, Guo D, Liu Z, Chen L, Zhong X, Cao W. Systemic treatment with GnRH agonist produces antidepressant-like effects in LPS induced depression male mouse model. Neuropharmacology 2023; 233:109560. [PMID: 37094770 DOI: 10.1016/j.neuropharm.2023.109560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/18/2023] [Accepted: 04/20/2023] [Indexed: 04/26/2023]
Abstract
Gonadotropin-releasing hormone (GnRH) is at the head of the neuroendocrine reproductive axis. However, the non-reproductive functions of GnRH expressed in various tissues, including hippocampus, are still not known. Here, we unveil a previously unknown effect of GnRH, which mediates depression-like behaviors through the modulation of microglia function during immune challenge. Specifically, we found that either systemic treatment with GnRH agonist or over-expression of endogenous hippocampal GnRH via viral tool abolished the depression-like behavior after LPS challenges in mice. And the anti-depressant of GnRH was dependent on the hippocampal GnRHR signaling, since antagonizing GnRHR by drug treatment or by hippocampal GnRHR knockdown could block the antidepressant-effect of GnRH agonist. Interestingly, we found that the peripheral GnRH treatment prevented the microglia activation mediated inflammation in the hippocampus of mice. In light of the research findings presented here, we propose that, at least in the hippocampus, GnRH appears to act on GnRHR to regulate higher order non-reproductive functions associated with the microglia mediated neuroinflammation. These findings also provide insights into the function and cross-talk of GnRH, a known neuropeptide hormone, in neuro-immune response.
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Affiliation(s)
- Yang Xu
- Institute of Neuroscience, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Wei Li
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Mengmeng Shi
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Xiaofan Xu
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Dongmin Guo
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Zhenghai Liu
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Ling Chen
- Department of Metabolism and Endocrinology, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Xiaolin Zhong
- Department of Metabolism and Endocrinology, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China.
| | - Wenyu Cao
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China.
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Gautam P, Ajit K, Das M, Taliyan R, Roy R, Banerjee A. Age-related changes in gonadotropin-releasing hormone (GnRH) splice variants in mouse brain. J Exp Zool A Ecol Integr Physiol 2023; 339:193-209. [PMID: 36336790 DOI: 10.1002/jez.2671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 09/07/2022] [Accepted: 10/07/2022] [Indexed: 11/09/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) is the primary regulator of the mammalian reproductive axis. We investigated the spatiotemporal expression of GnRH splice variants (V1, V2, and V3) and splicing factors (Srsf7, Srsf9, and Tra-2) in the male mice brain. Further, using in silico tools, we predicted protein structure and the reason for the low translational efficiency of V2 and V3. Messenger RNA levels of GnRH variants and splicing factors were quantified using real-time reverse transcription-polymerase chain reaction at different age groups. Our data show that expression of almost all the variants alters with aging in all the brain regions studied; even in comparison to the hypothalamus, several brain areas were found to have higher expression of these variants. Hypothalamic expression of splicing factors such as Srsf7, Srsf9, and Tra-2 also change with aging. Computational studies have translation repressors site on the V3, which probably reduces its translation efficiency. Also, V2 is an intrinsically disordered protein that might have a regulatory or signaling function. In conclusion, this study provides novel crucial information and multiple starting points for future analysis of GnRH splice variants in the brain.
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Affiliation(s)
- Pooja Gautam
- Department of Biological Sciences, BITS Pilani, KK Birla, Goa Campus, Goa, India
| | - Kamal Ajit
- Department of Biological Sciences, BITS Pilani, KK Birla, Goa Campus, Goa, India
| | - Moitreyi Das
- Department of Zoology, Goa University, Goa, India
| | - Rajeev Taliyan
- Department of Pharmacy, BITS Pilani, Pilani Campus, Rajasthan, India
| | | | - Arnab Banerjee
- Department of Biological Sciences, BITS Pilani, KK Birla, Goa Campus, Goa, India
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3
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Duittoz AH, Forni PE, Giacobini P, Golan M, Mollard P, Negrón AL, Radovick S, Wray S. Development of the gonadotropin-releasing hormone system. J Neuroendocrinol 2022; 34:e13087. [PMID: 35067985 PMCID: PMC9286803 DOI: 10.1111/jne.13087] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 12/02/2021] [Accepted: 12/22/2021] [Indexed: 11/29/2022]
Abstract
This review summarizes the current understanding of the development of the neuroendocrine gonadotropin-releasing hormone (GnRH) system, including discussion on open questions regarding (1) transcriptional regulation of the Gnrh1 gene; (2) prenatal development of the GnRH1 system in rodents and humans; and (3) paracrine and synaptic communication during migration of the GnRH cells.
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Affiliation(s)
| | - Paolo E. Forni
- Department of Biological SciencesUniversity at AlbanyAlbanyNYUSA
- The RNA InstituteUniversity at AlbanyAlbanyNYUSA
| | - Paolo Giacobini
- Laboratory of Development and Plasticity of the Postnatal BrainLille Neuroscience & Cognition, UMR‐S1172, Inserm, CHU LilleUniversity of LilleLilleFrance
| | - Matan Golan
- Institute of Animal SciencesAgricultural Research Organization – Volcani CenterRishon LetziyonIsrael
| | - Patrice Mollard
- Institute of Functional GenomicsCNRS, InsermMontpellier UniversityMontpellierFrance
| | - Ariel L. Negrón
- Clinical and Translational ResearchRutgers Robert Wood Johnson Medical SchoolNew BrunswickNJUSA
| | - Sally Radovick
- Clinical and Translational ResearchRutgers Robert Wood Johnson Medical SchoolNew BrunswickNJUSA
| | - Susan Wray
- Cellular and Developmental Neurobiology SectionNational Institute of Neurological Disorders and Stroke/National Institutes of HealthBethesdaMDUSA
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Kurian JR, Louis S, Keen KL, Wolfe A, Terasawa E, Levine JE. The Methylcytosine Dioxygenase Ten-Eleven Translocase-2 (tet2) Enables Elevated GnRH Gene Expression and Maintenance of Male Reproductive Function. Endocrinology 2016; 157:3588-603. [PMID: 27384303 PMCID: PMC5007894 DOI: 10.1210/en.2016-1087] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Reproduction depends on the establishment and maintenance of elevated GnRH neurosecretion. The elevation of primate GnRH release is accompanied by epigenetic changes. Specifically, cytosine residues within the GnRH gene promoter are actively demethylated, whereas GnRH mRNA levels and peptide release rise. Whether active DNA demethylation has an impact on GnRH neuron development and consequently reproductive function remains unknown. In this study, we investigated whether ten-eleven translocation (tet) enzymes, which initiate the process of active DNA demethylation, influence neuronal function and reproduction. We found that tet2 expression increases with age in the developing mouse preoptic area-hypothalamus and is substantially higher in a mature (GT1-7) than an immature (GN11) GnRH cell line. GnRH mRNA levels and mean GnRH peptide release elevated after overexpression of tet2 in GN11 cells, whereas CRISPR/cas9-mediated knockdown of tet2 in GT1-7 cells led to a significant decline in GnRH expression. Manipulations of tet2 expression altered tet2 genome binding and histone 3 lysine 4 trimethylation abundance at the GnRH promoter. Mice with selective disruption of tet2 in GnRH neurons (GnRH-specific tet2 knockout mice) exhibited no sign of altered pubertal timing in either sex, although plasma LH levels were significantly lower, and fecundity was altered specifically in adult male GnRH-specific tet2 knockout animals, indicating that tet2 may participate in the maintenance GnRH neuronal function. Exposure to bisphenol A, an environmental contaminant that alters GnRH neuron activity, caused a shift in tet2 subcellular localization and a decrease in histone 3 lysine 4 trimethylation abundance at the GnRH promoter. Finally, evaluation of tet2 protein interactions in GT1-7 cells suggests that the influence of tet2 on neuronal function are not limited to nuclear mechanisms but could depend on mitochondrial function, and RNA metabolism. Together, these studies implicate tet2 in the maintenance of GnRH neuronal function and neuroendocrine control of male reproduction.
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Affiliation(s)
- Joseph R Kurian
- Department of Obstetrics and Gynecology (J.R.K., S.L.), Southern Illinois University School of Medicine, Springfield, Illinois 62794; St. John's Hospital Carol Jo Vecchie Women and Children's Center (J.R.K.), Springfield, Illinois 62769; Wisconsin National Primate Research Center (K.L.K., E.T., J.E.L.), Madison, Wisconsin 53705; Department of Pediatrics and Physiology (A.W.), The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287; and Departments of Pediatrics (E.T.) and Neuroscience (J.E.L.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706
| | - Somaja Louis
- Department of Obstetrics and Gynecology (J.R.K., S.L.), Southern Illinois University School of Medicine, Springfield, Illinois 62794; St. John's Hospital Carol Jo Vecchie Women and Children's Center (J.R.K.), Springfield, Illinois 62769; Wisconsin National Primate Research Center (K.L.K., E.T., J.E.L.), Madison, Wisconsin 53705; Department of Pediatrics and Physiology (A.W.), The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287; and Departments of Pediatrics (E.T.) and Neuroscience (J.E.L.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706
| | - Kim L Keen
- Department of Obstetrics and Gynecology (J.R.K., S.L.), Southern Illinois University School of Medicine, Springfield, Illinois 62794; St. John's Hospital Carol Jo Vecchie Women and Children's Center (J.R.K.), Springfield, Illinois 62769; Wisconsin National Primate Research Center (K.L.K., E.T., J.E.L.), Madison, Wisconsin 53705; Department of Pediatrics and Physiology (A.W.), The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287; and Departments of Pediatrics (E.T.) and Neuroscience (J.E.L.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706
| | - Andrew Wolfe
- Department of Obstetrics and Gynecology (J.R.K., S.L.), Southern Illinois University School of Medicine, Springfield, Illinois 62794; St. John's Hospital Carol Jo Vecchie Women and Children's Center (J.R.K.), Springfield, Illinois 62769; Wisconsin National Primate Research Center (K.L.K., E.T., J.E.L.), Madison, Wisconsin 53705; Department of Pediatrics and Physiology (A.W.), The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287; and Departments of Pediatrics (E.T.) and Neuroscience (J.E.L.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706
| | - Ei Terasawa
- Department of Obstetrics and Gynecology (J.R.K., S.L.), Southern Illinois University School of Medicine, Springfield, Illinois 62794; St. John's Hospital Carol Jo Vecchie Women and Children's Center (J.R.K.), Springfield, Illinois 62769; Wisconsin National Primate Research Center (K.L.K., E.T., J.E.L.), Madison, Wisconsin 53705; Department of Pediatrics and Physiology (A.W.), The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287; and Departments of Pediatrics (E.T.) and Neuroscience (J.E.L.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706
| | - Jon E Levine
- Department of Obstetrics and Gynecology (J.R.K., S.L.), Southern Illinois University School of Medicine, Springfield, Illinois 62794; St. John's Hospital Carol Jo Vecchie Women and Children's Center (J.R.K.), Springfield, Illinois 62769; Wisconsin National Primate Research Center (K.L.K., E.T., J.E.L.), Madison, Wisconsin 53705; Department of Pediatrics and Physiology (A.W.), The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287; and Departments of Pediatrics (E.T.) and Neuroscience (J.E.L.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706
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Lunghi M, Galizi R, Magini A, Carruthers VB, Di Cristina M. Expression of the glycolytic enzymes enolase and lactate dehydrogenase during the early phase ofToxoplasmadifferentiation is regulated by an intron retention mechanism. Mol Microbiol 2015; 96:1159-75. [DOI: 10.1111/mmi.12999] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2015] [Indexed: 01/12/2023]
Affiliation(s)
- Matteo Lunghi
- Department of Chemistry, Biology and Biotechnology; University of Perugia; Perugia Italy
| | - Roberto Galizi
- Department of Experimental Medicine; University of Perugia; Perugia Italy
| | - Alessandro Magini
- Department of Chemistry, Biology and Biotechnology; University of Perugia; Perugia Italy
| | - Vern B. Carruthers
- Department of Microbiology and Immunology; University of Michigan Medical School; Ann Arbor MI USA
| | - Manlio Di Cristina
- Department of Chemistry, Biology and Biotechnology; University of Perugia; Perugia Italy
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Zhao S, Lu X, Zhang Y, Zhao X, Zhong M, Li S, Lun J. Identification of a novel alternative splicing variant of hemocyanin from shrimp Litopenaeus vannamei. Immunol Lett 2013; 154:1-6. [PMID: 23954808 DOI: 10.1016/j.imlet.2013.08.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Revised: 07/28/2013] [Accepted: 08/06/2013] [Indexed: 10/26/2022]
Abstract
Recent evidences suggest that invertebrates express families of immune molecules with high levels of sequence diversity. Hemocyanin is an important non-specific immune molecule present in the hemolymph of both mollusks and arthropods. In the present study, we characterized a novel alternative splicing variant of hemocyanin (cHE1) from Litopenaeus vannamei that produced mRNA transcript of 2579 bp in length. The isoform contained two additional sequences of 296 and 267 bp in the 5'- and 3'-terminus respectively, in comparison to that of wild type hemocyanin (cHE). Sequence of cHE1 shows 100% identity to that of hemocyanin genomic DNA (HE, which does not form an open reading frame), suggesting that cHE1 might be an alternative splicing variant due to intron retention. Moreover, cHE1 could be detected by RT-PCR from five tissues (heart, gill, stomach, intestine and brain), and from shrimps at stages from nauplius to mysis larva. Further, cHE1 mRNA transcripts were significantly increased in hearts after 12h of infection with Vibrio parahemolyticus or poly I: C, while no significant difference in the transcript levels of hepatopancreas cHE was detected in the pathogen-treated shrimps during the period. In summary, these studies suggested a novel splicing variant of hemocyanin in shrimp, which might be involved in shrimp resistance to pathogenic infection.
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Affiliation(s)
- Shan Zhao
- Department of Biology and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
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7
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Wang L, Chadwick W, Park SS, Zhou Y, Silver N, Martin B, Maudsley S. Gonadotropin-releasing hormone receptor system: modulatory role in aging and neurodegeneration. CNS Neurol Disord Drug Targets 2010; 9:651-60. [PMID: 20632963 PMCID: PMC2967575 DOI: 10.2174/187152710793361559] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Accepted: 02/25/2010] [Indexed: 12/15/2022]
Abstract
Receptors for hormones of the hypothalamic-pituitary-gonadal axis are expressed throughout the brain. Age-related decline in gonadal reproductive hormones cause imbalances of this axis and many hormones in this axis have been functionally linked to neurodegenerative pathophysiology. Gonadotropin-releasing hormone (GnRH) plays a vital role in both central and peripheral reproductive regulation. GnRH has historically been known as a pituitary hormone; however, in the past few years, interest has been raised in GnRH actions at non-pituitary peripheral targets. GnRH ligands and receptors are found throughout the brain where they may act to control multiple higher functions such as learning and memory function and feeding behavior. The actions of GnRH in mammals are mediated by the activation of a unique rhodopsin-like G protein-coupled receptor that does not possess a cytoplasmic carboxyl terminal sequence. Activation of this receptor appears to mediate a wide variety of signaling mechanisms that show diversity in different tissues. Epidemiological support for a role of GnRH in central functions is evidenced by a reduction in neurodegenerative disease after GnRH agonist therapy. It has previously been considered that these effects were not via direct GnRH action in the brain, however recent data has pointed to a direct central action of these ligands outside the pituitary. We have therefore summarized the evidence supporting a central direct role of GnRH ligands and receptors in controlling central nervous physiology and pathophysiology.
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Affiliation(s)
- Liyun Wang
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Biomedical Research Center, 251 Bayview Boulevard, Baltimore MD 21224
| | - Wayne Chadwick
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Biomedical Research Center, 251 Bayview Boulevard, Baltimore MD 21224
| | - Soo-Sung Park
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Biomedical Research Center, 251 Bayview Boulevard, Baltimore MD 21224
| | - Yu Zhou
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Biomedical Research Center, 251 Bayview Boulevard, Baltimore MD 21224
| | - Nathan Silver
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Biomedical Research Center, 251 Bayview Boulevard, Baltimore MD 21224
| | - Bronwen Martin
- Metabolism Unit, Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Biomedical Research Center, 251 Bayview Boulevard, Baltimore MD 21224
| | - Stuart Maudsley
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Biomedical Research Center, 251 Bayview Boulevard, Baltimore MD 21224
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Park E, Lee MS, Baik SM, Cho EB, Son GH, Seong JY, Lee KH, Kim K. Nova-1 mediates glucocorticoid-induced inhibition of pre-mRNA splicing of gonadotropin-releasing hormone transcripts. J Biol Chem 2009; 284:12792-800. [PMID: 19282286 DOI: 10.1074/jbc.m807386200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glucocorticoid (GC) is known to affect the reproductive system by suppressing the gonadotropin-releasing hormone (GnRH) gene expression in the hypothalamus. However, the mechanism of this effect is poorly understood. We show here that the GC-induced reduction of GnRH mRNA is due to attenuation of a post-transcriptional process i.e. splicing of intron A. Treatment of dexamethasone (DEX), a synthetic GC, lowered GnRH mRNA transcripts and was accompanied by reduced excision of the first intron (intron A) from the GnRH pre-mRNA both in vitro and in vivo. While seeking to identify the splicing factors involved in GC-inhibited GnRH pre-mRNA splicing, we found that DEX down-regulated neuro-oncological ventral antigen-1 (Nova-1) mRNA and protein and that knockdown of Nova-1 reduced intron A excision from GnRH pre-mRNA. Nova-1 overexpression reversed the DEX-induced reduction of intron A excision. Nova-1 appears to promote intron A excision by binding to the distal region of exon 1 of the GnRH pre-mRNA. Taken together, our findings indicate that the intron A excision by Nova-1 is a target of GC for down-regulation of GnRH gene expression, and more importantly, we characterized Nova-1, a brain-enriched splicing regulator responsible for GnRH pre-mRNA splicing.
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Affiliation(s)
- Eonyoung Park
- School of Biological Sciences, Seoul National University, Seoul, Korea
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Skinner DC, Albertson AJ, Navratil A, Smith A, Mignot M, Talbott H, Scanlan-Blake N. Effects of gonadotrophin-releasing hormone outside the hypothalamic-pituitary-reproductive axis. J Neuroendocrinol 2009; 21:282-92. [PMID: 19187469 PMCID: PMC2669307 DOI: 10.1111/j.1365-2826.2009.01842.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Gonadotrophin-releasing hormone (GnRH) is a hypothalamic decapeptide with an undisputed role as a primary regulator of gonadal function. It exerts this regulation by controlling the release of gonadotrophins. However, it is becoming apparent that GnRH may have a variety of other vital roles in normal physiology. A reconsideration of the potential widespread action that this traditional reproductive hormone exerts may lead to the generation of novel therapies and provide insight into seemingly incongruent outcomes from current treatments using GnRH analogues to combat diseases such as prostate cancer.
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Affiliation(s)
- D C Skinner
- Neurobiology Program and Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA.
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Yue C, Ponzio TA, Fields RL, Gainer H. Oxytocin and vasopressin gene expression and RNA splicing patterns in the rat supraoptic nucleus. Physiol Genomics 2008; 35:231-42. [PMID: 18765859 PMCID: PMC2585020 DOI: 10.1152/physiolgenomics.90218.2008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Accepted: 08/28/2008] [Indexed: 11/22/2022] Open
Abstract
In this study, we test the hypothesis that there are differential splicing patterns between the expressed oxytocin (OT) and vasopressin (VP) genes in the rat supraoptic nucleus (SON). We quantify the low abundance, intron-containing heteronuclear RNAs (hnRNAs) and the higher abundance mRNAs in the SON using two-step, quantitative SYBR Green real-time reverse transcription (RT)-PCR and external standard curves constructed using synthetic 90 nt sense-strand oligonucleotides. The levels of OT and VP mRNA in the SON were found to be similar, approximately 10(8) copies/SON pair, whereas the copy numbers of VP hnRNAs containing intron 1 or 2 and the OT hnRNA containing intron 1 are much lower, i.e., approximately 10(2)-10(3) copies/rat SON pair. However, the estimated copy number of the intron 2-containing OT hnRNA is much larger, approximately 10(6) copies/SON pair. The relative distributions of all the OT and VP RNA species were invariant and independent of the physiological status of the rats (e.g., osmotically stimulated or lactating rats). Using intron-specific riboprobes against hnRNAs, we demonstrate by fluorescence in situ hybridization strong signals of OT hnRNA containing intron 2 predominantly in the cytoplasm, in contrast to the localization of the VP hnRNA found only in the nuclei. Taken together, these data support the view that the splicing patterns between OT and VP gene transcripts are different and show that there is a selective cytoplasmic retention of OT intron 2.
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Affiliation(s)
- Chunmei Yue
- Molecular Neuroscience Section, Laboratory of Neurochemistry, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, USA
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11
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Xu Q, Walker D, Bernardo A, Brodbeck J, Balestra ME, Huang Y. Intron-3 retention/splicing controls neuronal expression of apolipoprotein E in the CNS. J Neurosci 2008; 28:1452-9. [PMID: 18256266 DOI: 10.1523/JNEUROSCI.3253-07.2008] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Neuronal expression of apolipoprotein (apo) E4 may contribute to the pathogenesis of Alzheimer's disease (AD). In studying how apoE expression is regulated in neurons, we identified a splicing variant of apoE mRNA with intron-3 retention (apoE-I3). ApoE-I3 mRNA was detected in neuronal cell lines and primary neurons, but not in astrocytic cell lines or primary astrocytes, from humans and mice by reverse transcription (RT)-PCR. In both wild-type and human apoE knock-in mice, apoE-I3 was found predominantly in cortical and hippocampal neurons by in situ hybridization. Cell fractionation and quantitative RT-PCR revealed that over 98% of the apoE-I3 mRNA was retained in the nucleus without protein translation. In transfected primary neurons, apoE expression increased dramatically when intron-3 was deleted from a genomic DNA construct and decreased markedly when intron-3 was inserted into a cDNA construct, suggesting that intron-3 retention/splicing controls apoE expression in neurons. In response to excitotoxic challenge, the apoE-I3 mRNA was markedly increased in morphologically normal hippocampal neurons but reduced in degenerating hippocampal neurons in mice; apoE mRNA showed the opposite pattern. This apparent precursor-product relationship between apoE-I3 and apoE mRNA was supported by a transcriptional inhibition study. Thus, neuronal expression of apoE is controlled by transcription of apoE-I3 under normal conditions and by processing of apoE-I3 into mature apoE mRNA in response to injury.
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12
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Park E, Han J, Son GH, Lee MS, Chung S, Park SH, Park K, Lee KH, Choi S, Seong JY, Kim K. Cooperative actions of Tra2alpha with 9G8 and SRp30c in the RNA splicing of the gonadotropin-releasing hormone gene transcript. J Biol Chem 2005; 281:401-9. [PMID: 16249178 DOI: 10.1074/jbc.m505814200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In earlier studies, we demonstrated that excision of the first intron (intron A) from the gonadotropin-releasing hormone (GnRH) transcript is highly cell type- and developmental stage-specific. The removal of GnRH intron A requires exonic splicing enhancers on exons 3 and 4 (ESE3 and ESE4, respectively). Tra2alpha,a serine/arginine-rich (SR)-like protein, specifically binds to ESE4, although it requires additional nuclear co-factors for efficient removal of this intron. In the present study, we demonstrate the cooperative action of multiple SR proteins in the regulation of GnRH pre-mRNA splicing. SRp30c specifically binds to both ESE3 and ESE4, whereas 9G8 binds to an element in exon 3 and strongly enhances the excision of GnRH intron A in the presence of minimal amount of other nuclear components. Interestingly, Tra2alpha can interact with either 9G8 or SRp30c, whereas no interaction between 9G8 and SRp30c is observed. Tra2alpha has an additive effect on the RNA binding of these proteins. Overexpression or knock-down of these three proteins in cultured cells further suggests their essential role in intron A excision activities, and their presence in GnRH neurons of the mouse preoptic area further strengthens this possibility. Together, these results indicate that interaction of Tra2alpha with 9G8 and SRp30c appears to be crucial for ESE-dependent GnRH pre-mRNA splicing, allowing efficient generation of mature mRNA in GnRH-producing cells.
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Affiliation(s)
- Eonyoung Park
- School of Biological Sciences, Seoul National University, Seoul 151-742, Korea
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Son GH, Park E, Jung H, Han J, Lee KH, Seong JY, Kim K. GnRH pre-mRNA splicing: solving the mystery of a nature's knockout, hpg mouse. Biochem Biophys Res Commun 2005; 326:261-7. [PMID: 15582572 DOI: 10.1016/j.bbrc.2004.10.207] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2004] [Indexed: 10/26/2022]
Abstract
The hypogonadal (hpg) mouse represents a unique animal model for hypogonadism. In this mutant the truncation of the gene encoding gonadotropin-releasing hormone (GnRH) leads to drastically lowered gonadotropin levels and prepubertal gonads. The deletional mutation encompasses only the distal half of the gene leaving the region encoding GnRH decapeptide intact. The partially deleted gene is transcriptionally active, but translationally inactive. Even though several aspects have been considered to account for the phenomenon, there is no satisfactory explanation so far. Recent reports showed that excision of the GnRH first intron is delicately regulated in a cell type- and developmental stage-specific manner mediated by putative-specific splicing factors acting on cis-acting elements located in exon 3 and 4, and is significantly decreased in hpg mouse whose exonic splicing enhancers are absent. Furthermore, the suppressing effect of intron A retention on the translational activity of downstream open reading frame was reported, giving an insight into the understanding the mystery of hpg mice.
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Affiliation(s)
- Gi Hoon Son
- School of Biological Sciences, Seoul National University, Seoul 151-742, Republic of Korea
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14
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Lee KH, Park JY, Kim K. NMDA receptor-mediated calcium influx plays an essential role in myoblast fusion. FEBS Lett 2004; 578:47-52. [PMID: 15581614 DOI: 10.1016/j.febslet.2004.10.076] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2004] [Revised: 10/21/2004] [Accepted: 10/22/2004] [Indexed: 11/25/2022]
Abstract
Ca2+ influx is known to be prerequisite for myoblast fusion during skeletal muscle differentiation. Here, we show that the N-methyl-D-aspartate (NMDA) receptor is involved in the Ca2+ influx of C2C12 myoblasts. NMDA receptor (NR) 1 and NR2D were expressed in the myoblasts during muscle differentiation. Using Ca2+ imaging analysis, Ca2+ influx through NRs was directly measured at a single-cell level. l-Glutamate increased myoblast fusion as well as intracellular Ca2+ levels, and both effects were completely blocked by MK801, a selective antagonist of NRs. Furthermore, treatment with the Ca2+ ionophore A23187 recovered MK801-mediated inhibition of myoblast fusion. These results suggest that the NRs may play an important role in myoblast fusion by mediating Ca2+ influx.
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Affiliation(s)
- Kun Ho Lee
- School of Biological Sciences, Seoul National University, Seoul, 151-742, Republic of Korea
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15
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Affiliation(s)
- D L Black
- Howard Hughes Medical Institute, University of California, Los Angeles, MRL 5-748, 675 Charles E. Young Dr. South, Los Angeles, California 90095, USA
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16
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Son GH, Jung H, Seong JY, Choe Y, Geum D, Kim K. Excision of the first intron from the gonadotropin-releasing hormone (GnRH) transcript serves as a key regulatory step for GnRH biosynthesis. J Biol Chem 2003; 278:18037-44. [PMID: 12639969 DOI: 10.1074/jbc.m209850200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The mammalian gonadotropin-releasing hormone (GnRH) gene consists of four short exons (denoted as 1, 2, 3, and 4) and three intervening introns (A, B, and C). Recently, we demonstrated that excision of the first intron (intron A) from the GnRH transcript is regulated in a tissue- and developmental stage-specific fashion and is severely attenuated in hypogonadal (hpg) mouse because of its lack of exonic splicing enhancers (ESE) 3 and 4. In the present study, we examined the influence of intron A on translational efficiency, thereby establishing a post-transcriptional control over GnRH biosynthesis. First, we verified that an intron A-retained GnRH transcript is a splicing variant but not a splicing intermediate. Intron A-retained transcripts can be transported to the cytoplasm in contrast to intron B-containing transcripts, which are restricted to the nucleus. This result implicates the intron A-retained GnRH transcript as a splicing variant; it has a long 5'-untranslated region, as the GnRH prohormone open reading frame (ORF) begins on exon 2. We investigated whether an intron A-retained GnRH transcript can properly initiate translation at the appropriate start codon and found that intron A completely blocks the translation initiation of its downstream reporter ORF both in vivo and in vitro. The inhibition of translation initiation appears to be due to the presence of a tandem repeat of ATG sequences within intron A. Constructs bearing mutations of ATGs to AAGs restored translation initiation at the downstream start codon; the extent of this restoration correlated with the number of mutated ATGs. Besides the failure in the translation initiation of GnRH-coding region in the intron A-containing variant, the present study also suggests that the interference between mature GnRH mRNA and intron A-retained splicing variant could occur to lower the efficiency of GnRH biosynthesis in the GT1-1-immortalized GnRH-producing cell line. Therefore, our results indicate that the precise and efficient excision of intron A and the joining of adjacent exons may be a critical regulatory step for the post-transcriptional regulation of GnRH biosynthesis.
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Affiliation(s)
- Gi Hoon Son
- School of Biological Sciences, Seoul National University, Seoul 151-742, Korea
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17
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Pierantoni R, Cobellis G, Meccariello R, Fasano S. Evolutionary aspects of cellular communication in the vertebrate hypothalamo-hypophysio-gonadal axis. Int Rev Cytol 2003; 218:69-141. [PMID: 12199520 DOI: 10.1016/s0074-7696(02)18012-0] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
This review emphasizes the comparative approach for developing insight into knowledge related to cellular communications occurring in the hypothalamus-pituitary-gonadal axis. Indeed, research on adaptive phenomena leads to evolutionary tracks. Thus, going through recent results, we suggest that pheromonal communication precedes local communication which, in turn, precedes communication via the blood stream. Furthermore, the use of different routes of communication by a certain mediator leads to a conceptual change related to what hormones are. Nevertheless, endocrine communication should leave out of consideration the source (glandular or not) of mediator. Finally, we point out that the use of lower vertebrate animal models is fundamental to understanding general physiological mechanisms. In fact, different anatomical organization permits access to tissues not readily approachable in mammals.
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18
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Affiliation(s)
- Jin Han
- School of Biological Sciences, Seoul National University, Seoul 151-742, Korea
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19
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Seong JY, Han J, Park S, Wuttke W, Jarry H, Kim K. Exonic splicing enhancer-dependent splicing of the gonadotropin-releasing hormone premessenger ribonucleic acid is mediated by tra2alpha, a 40-kilodalton serine/arginine-rich protein. Mol Endocrinol 2002; 16:2426-38. [PMID: 12403832 DOI: 10.1210/me.2001-0297] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In an earlier study, we found that excision of the first intron (intron A) from the rat GnRH primary transcript is attenuated in non-GnRH-producing cells. This attenuation can be partially relieved by exonic splicing enhancers (ESEs) located in GnRH exons 3 and 4. In the present study, we confirmed that intron A of the mouse GnRH pre-mRNA was not excised in a HeLa nuclear extract (NE) in vitro or in COS-7 cells in vivo. Intron A could, however, be partially removed when exon 3 and/or 4 were linked to exon 2. In the presence of an ESE in exon 4 (ESE4), an addition of GT1 NE further increased the excision rate of intron A, whereas the addition of KK1 (a non-GnRH-producing cell) NE decreased it. To define the GnRH neuron-specific splicing activity, GT1 NE was fractionated by ultracentrifugation and ammonium sulfate precipitation. A 50-90% ammonium sulfate pellet (ASP50-90) fraction was further precipitated with 20 mM MgCl(2) to isolate a serine/arginine-rich (SR) protein fraction. Among the ASP fractions, ASP40-50 significantly increased the excision rate of intron A in the presence of HeLa NE or SR protein-rich fraction. However, the ASP40-50 fraction alone could not remove intron A. This result suggests the presence of a cofactor protein(s) in the ASP40-50 fraction that may mediate the interaction between a 3' spliceosome complex and the ESE4-SR protein complex. UV cross-linking and gel mobility shift analysis revealed that Tra2alpha but not other SR proteins tested, specifically binds to ESE4. Moreover, Tra2alpha stimulated intron A excision in a dose-dependent manner. These results imply that Tra2alpha and a cofactor protein in the ASP40-50 fraction are involved in mediating the GnRH neuron-specific excision of intron A from the GnRH primary transcript.
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Affiliation(s)
- Jae Young Seong
- Hormone Research Center, Chonnam National University, Kwangju 500-757, Korea
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20
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Uzbekova S, Lareyre JJ, Madigou T, Davail B, Jalabert B, Breton B. Expression of prepro-GnRH and GnRH receptor messengers in rainbow trout ovary depends on the stage of ovarian follicular development. Mol Reprod Dev 2002; 62:47-56. [PMID: 11933160 DOI: 10.1002/mrd.10065] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Gonadotropin-Releasing Hormones (GnRHs) are decapeptides well known to regulate the reproductive cycle. They are expressed not only in the brain, but also in other tissues including the gonads. It is believed that they may be involved in the endocrine and paracrine regulation of the reproductive cycle. To date, two forms of GnRH have been identified in salmonids: salmon (sGnRH) and chicken II (cGnRH-II). In the present study, the temporal expression of sGnRH-1, sGnRH-2, cGnRH-II, and rtGnRH receptor genes was studied in rainbow trout ovary during the reproductive cycle according to the stages of follicular development. Using RT-PCR coupled with Southern-blot hybridization, sGnRH-1, sGnRH-2, cGnRH-II, and rtGnRH-R transcripts were detected in morphologically nondifferentiated ovaries as early as 55-65 days post-fertilization and throughout all stages of vitellogenesis. Using Northern blot analysis, cGnRH-II mRNA was detected only in immature previtellogenic ovary, whereas sGnRH mRNA was detected also during early and mid-exogenous vitellogenesis. No sGnRH mRNA was detected at the end of vitellogenesis. In maturing pre-ovulated ovary, sGnRH transiently reappeared before germinal vesicle breakdown (GVBD) and decreased thereafter. A few days after ovulation, a strong sGnRH mRNA expression was found in ovarian tissue as the eggs were kept in the body cavity of females. However, in females stripped just after ovulation, sGnRH mRNA levels remained low in ovary during several weeks. Fully spliced sGnRH-1 and sGnRH-2 messengers were mostly expressed during the reproductive cycle; however different sGnRH-1 and sGnRH-2 splicing variants containing intronic sequences were also detected. Some of these messengers may encode prepro-GnRH precursors with truncated GnRH-associated peptides. The stage-dependent expression and different cell localization of sGnRH, cGnRH-II, and rtGnRH-R transcripts suggest that GnRH-like peptides may have different roles in the paracrine regulation of ovarian follicular development.
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Affiliation(s)
- Svetlana Uzbekova
- Equipe Sexualité et Reproduction des Poissons, Institut National de la Recherche Agronomique, Station Commune de Recherche en Ichtyophysiologie, Biodiversité et Environnement, Campus de Beaulieu, 35042 Rennes Cedex, France.
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Romano M, Marcucci R, Baralle FE. Splicing of constitutive upstream introns is essential for the recognition of intra-exonic suboptimal splice sites in the thrombopoietin gene. Nucleic Acids Res 2001; 29:886-94. [PMID: 11160920 PMCID: PMC29620 DOI: 10.1093/nar/29.4.886] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The human thrombopoietin (TPO) gene, which codes for the principal cytokine involved in platelet maturation, shows a peculiar alternative splicing of its last exon, where an intra-exonic 116 nt alternative intron is spliced out in a fraction of its mRNA. To characterize the molecular mechanism underlying this alternative splicing, minigenes of TPO genomic constructs with variable exon-intron configurations or carrying exclusively the TPO cDNA were generated and transiently transfected in the Hep3B cell line. We have found that the final rate of the alternative intron splicing is determined by three elements: the presence of upstream constitutive introns, the suboptimal splice sites of the alternative intron and the length of the alternative intron itself. Our results indicate that the recognition of suboptimal intra-exonic splice junctions in the TPO gene is influenced by the assembly of the spliceosome complex on constitutive introns and by a qualitative scanning of the sequence by the transcriptional/splicing machinery complex primed by upstream splicing signals.
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Affiliation(s)
- M Romano
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34012 Trieste, Italy
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22
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Abstract
The glutamate analog N-methyl-D,L-aspartate (NMA) affects the regulation of GnRH and LH release in mammals. Several laboratories have reported a rapid and transient increase in GnRH mRNA levels of male rats after NMA injection. Studies employing the simultaneous measurements of nuclear GnRH primary transcript RNA, a reflection of gene transcription, and GnRH mRNA suggest that NMA's effect on GnRH gene expression in the rat is likely due to post-transcriptional regulation. Despite the increasingly widespread use of transgenic mice, surprisingly little is known about the regulation of GnRH gene expression in the mouse. In this study, we assessed in detail the effects of NMA on GnRH gene expression in adult male mice. In the first experiment, GnRH mRNA levels in mice killed 60-min post-NMA injection (20 mg/kg bw, ip; n=9/treatment group) were lower (P<0.05) when compared to controls (saline vehicle). In the second experiment, mice (n=7/treatment group) were administered NMA or saline vehicle and were killed at 15-, 60- and 120-min post-injection. Consistent with the first experiment, treatment with NMA resulted in a significant decrease (P<0.05) in cytoplasmic GnRH mRNA compared to control levels at 15- and 60-min but not 120-min. NMA treatment decreased the nuclear GnRH primary transcript RNA at 120-min but not at earlier time points. In summary, we have shown that regulation by NMA of GnRH gene expression in mice differs substantially from rats. This differential regulation of GnRH gene expression between rats and mice warrants further investigation.
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Affiliation(s)
- T J Wu
- Fishberg Research Center for Neurobiology, Mount Sinai School of Medicine, 1425 Madison Avenue, New York, NY, USA
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