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Payankaulam S, Raicu AM, Arnosti DN. Transcriptional Regulation of INSR, the Insulin Receptor Gene. Genes (Basel) 2019; 10:genes10120984. [PMID: 31795422 PMCID: PMC6947883 DOI: 10.3390/genes10120984] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 11/19/2019] [Accepted: 11/23/2019] [Indexed: 01/19/2023] Open
Abstract
The insulin receptor gene encodes an evolutionarily conserved signaling protein with a wide spectrum of functions in metazoan development. The insulin signaling pathway plays key roles in processes such as metabolic regulation, growth control, and neuronal function. Misregulation of the pathway features in diabetes, cancer, and neurodegenerative diseases, making it an important target for clinical interventions. While much attention has been focused on differential pathway activation through ligand availability, sensitization of overall signaling may also be mediated by differential expression of the insulin receptor itself. Although first characterized as a “housekeeping” gene with stable expression, comparative studies have shown that expression levels of the human INSR mRNA differ by tissue and in response to environmental signals. Our recent analysis of the transcriptional controls affecting expression of the Drosophila insulin receptor gene indicates that a remarkable amount of DNA is dedicated to encoding sophisticated feedback and feed forward signals. The human INSR gene is likely to contain a similar level of transcriptional complexity; here, we summarize over three decades of molecular biology and genetic research that points to a still incompletely understood regulatory control system. Further elucidation of transcriptional controls of INSR will provide the basis for understanding human genetic variation that underlies population-level physiological differences and disease.
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Affiliation(s)
- Sandhya Payankaulam
- Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Rd. 413 Biochemistry, East Lansing, MI 48824, USA;
| | - Ana-Maria Raicu
- Cell and Molecular Biology Program, Michigan State University, 603 Wilson Rd. 413 Biochemistry, East Lansing, MI 48824, USA;
| | - David N. Arnosti
- Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Rd. 413 Biochemistry, East Lansing, MI 48824, USA;
- Cell and Molecular Biology Program, Michigan State University, 603 Wilson Rd. 413 Biochemistry, East Lansing, MI 48824, USA;
- Correspondence: ; Tel.: +1-(517)-432-5504
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Mehdad A, Campos NA, Arruda SF, Siqueira EMDA. Iron Deprivation May Enhance Insulin Receptor and Glut4 Transcription in Skeletal Muscle of Adult Rats. J Nutr Health Aging 2015; 19:846-54. [PMID: 26412289 DOI: 10.1007/s12603-015-0541-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVES Considering that phenotype related to iron overload associated with pathological conditions differs from that caused by dietary iron excess, our study set out to evaluate the impact of dietary iron restriction and dietary iron supplementation on oxidative stress and functional outcome in adult, healthy rats. METHODS adult rats were divided into the three groups and fed diets containing 10, 35 or 350 mg/kg iron (restricted-diet, control-diet and supplemented- diet groups, respectively) for 78 days. Hematological variables, fasting blood glucose, hepatic enzyme activity and C-reactive protein levels were analyzed. Iron and glycogen concentrations in liver and skeletal muscle were determined. The extent of tissue damage caused by either dietary iron restriction or iron supplementation was accessed by measuring malondialdehyde, carbonyl, NADPH oxidase, glutathione peroxidase, glutathione reductase and glutathione-s-transferase in various tissues. The mRNA expression levels of insulin receptor, glucose transporter 4 and p53 were also determined. RESULTS Fasting blood glucose values trended toward a decrease by dietary iron restriction, moreover, hepatic glycogen content decreased with concomitant increases in skeletal muscle. In addition, dietary iron restriction resulted in a twofold increase in mRNA expression of Insr and fourfold increase in Glut4 expression in skeletal muscle. Although the dietary iron restriction did not affect body iron status, it caused hepatic low oxidative damages. However, high liver NADPH oxidase activity and increased levels of protein oxidation in muscle were observed. Chronic feeding of high iron diet induces iron overload and resulted in elevated levels of stress markers in tissues. CONCLUSION Dietary iron deprivation may improve insulin receptor and glucose transporter transcription in muscle; however, our results show that dietary iron restriction can prevent and/or promote oxidative damage in a tissue-specific manner, emphasizing the importance of maintaining optimal iron intake.
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Affiliation(s)
- A Mehdad
- Azadeh Mehdad, Laboratory of Molecular biophysic, Instituto of Biology, Dep. Cellular Biology, University of Brasilia (UnB) Brazil,
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Caruso MA, Sheridan MA. The expression of insulin and insulin receptor mRNAs is regulated by nutritional state and glucose in rainbow trout (Oncorhynchus mykiss). Gen Comp Endocrinol 2012; 175:321-8. [PMID: 22154645 DOI: 10.1016/j.ygcen.2011.11.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 11/16/2011] [Accepted: 11/18/2011] [Indexed: 11/16/2022]
Abstract
Many species of fish, including rainbow trout, possess multiple INS- and IR-encoding mRNAs. In this study, rainbow trout (Oncorhynchus mykiss) were used as a model to study the regulation of INS (INS1, INS2) and IR (IR1, IR2, IR3, and IR4) mRNA expression by nutritional state and glucose. In the nutritional state study, fish were either fed continuously, fasted (4 or 6 weeks), or fasted 4 weeks, then refed for 2 weeks. Nutritional state regulated INS and IR mRNA expression in a subtype- and tissue-specific manner. A 4-week fast reduced INS1 expression in endocrine pancreas (Brockmann body) and of INS1 and INS2 in brain, whereas a 6-week fast reduced the expression of both INS1 and INS2 in pancreas but only of INS1 in brain. Refeeding only restored INS2 levels in pancreas. In adipose tissue, by contrast, a 4-week fast increased INS1 expression, and a 6-week fast increased the expression of both INS1 and INS2. Nutritional state also modulated the pattern of IR mRNA expression. Fasting for 4 weeks resulted in no significant change in IR expression. Prolonged fasting (6 weeks) increased the expression of IR4 mRNA in the pancreas, adipose tissue, cardiac muscle, and gill; however, fasting decreased expression of IR3 mRNA in liver. Refeeding restored fasting-associated increases in IR4 expression in pancreas, adipose tissue, cardiac muscle, and gill, but had no effect on the fasting-associated decrease in IR3 expression in liver. Glucose differentially regulated the expression of INS and IR mRNAs in Brockmann bodies and liver pieces incubated in vitro, respectively. Low glucose (1 mM) reduced pancreatic expression of both INS1 and INS2 mRNAs compared to levels observed at 4 or 10 mM glucose. In the liver, IR1 and IR2 mRNA expression was insensitive to glucose concentration, whereas expression of IR3 and IR4 was attenuated at 1 and 10 mM compared to 4 mM glucose. These findings indicate that the pattern of INS and IR expression in selected tissues is regulated by nutritional state and glucose.
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Affiliation(s)
- Michael A Caruso
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58108, USA
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Shiraishi JI, Yanagita K, Fukumori R, Sugino T, Fujita M, Kawakami SI, McMurtry JP, Bungo T. Comparisons of insulin related parameters in commercial-type chicks: Evidence for insulin resistance in broiler chicks. Physiol Behav 2011; 103:233-9. [PMID: 21316379 DOI: 10.1016/j.physbeh.2011.02.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 01/07/2011] [Accepted: 02/04/2011] [Indexed: 11/19/2022]
Abstract
The aim of this study is to elucidate whether insulin acts differentially within the central nervous system (CNS) of two types of commercial chicks to control ingestive behavior. Male layer and broiler chicks (4-day-old) were intracerebroventricularly (ICV) injected with saline or insulin under satiated and starved conditions. Feed intake was measured at 30, 60 and 120 min after treatment. Secondly, blood and hypothalamus were collected from both chick types under ad libitum feeding and fasting for 24 h. Plasma insulin concentration was measured by time-resolved fluoro-immunoassay. Hypothalamic insulin receptor mRNA expression levels were measured by quantitative RT-PCR. The ICV injection of insulin significantly inhibited feed consumption in layer chicks when compared with saline (P<0.05), but not broiler chicks (P>0.1). Plasma insulin concentration of both chick types significantly decreased following 24 h of fasting, while insulin concentrations in the broiler chicks were significantly higher compared to the layers fed under ad libitum conditions. Hypothalamic insulin receptor mRNA expression levels were significantly lower (P<0.05) in broiler chicks than in layer ones under ad libitum feeding. Feed deprivation significantly decreased insulin receptor mRNA levels in layer chicks (P<0.01), but not in broiler chicks (P>0.1). Moreover, plasma insulin concentrations correlated negatively with hypothalamic insulin receptor protein expression in the two types of chicks fed ad libitum (P<0.05). These results suggest that insulin resistance exists in the CNS of broiler chicks, possibly due to persistent hyperinsulinemia, which results in a down-regulation of CNS insulin receptor expression compared to that in layer chicks.
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Affiliation(s)
- Jun-Ichi Shiraishi
- Laboratory of Animal Behavior and Physiology, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan
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Dongiovanni P, Valenti L, Ludovica Fracanzani A, Gatti S, Cairo G, Fargion S. Iron depletion by deferoxamine up-regulates glucose uptake and insulin signaling in hepatoma cells and in rat liver. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 172:738-47. [PMID: 18245813 DOI: 10.2353/ajpath.2008.070097] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Iron depletion improves insulin resistance in patients with nonalcoholic fatty liver disease and diabetes and also stabilizes the hypoxia-inducible factor (HIF)-1, resulting in increased glucose uptake in vitro. This study investigated the effect of iron depletion by deferoxamine on insulin signaling and glucose uptake in HepG2 hepatocytes and in rat liver. In HepG2 cells, deferoxamine stabilized HIF-1alpha and induced the constitutive glucose transporter Glut1 and the insulin receptor. Up-regulation of insulin receptor by deferoxamine was mimicked by the intracellular iron chelator deferasirox and the hypoxia inducer CoCl2 and required the HIF-1 obligate partner ARNT/HIF-1beta. Iron depletion increased insulin receptor activity, whereas iron supplementation had the opposite effect. Deferoxamine consistently increased the phosphorylation status of Akt/PKB and its targets FoxO1 and Gsk3beta, which mediate the effect of insulin on gluconeogenesis and glycogen synthesis, and up-regulated genes involved in glucose uptake and utilization. Iron depletion of Sprague-Dawley rats increased HIF-1alpha expression, improved glucose clearance, and was associated with up-regulation of insulin receptor and Akt/PKB levels and of glucose transport in hepatic tissue. Conversely, gluconeogenic genes were not affected. In rats with fatty liver because of a high-calorie and high-fat diet, glucose clearance was increased by iron depletion and decreased by iron supplementation. Thus, iron depletion by deferoxamine up-regulates glucose uptake, and increases insulin receptor activity and signaling in hepatocytes in vitro and in vivo.
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Affiliation(s)
- Paola Dongiovanni
- Department of Internal Medicine, Ospedale Maggiore Policlinico Mangiagalli Regina Elena Istituto Ricovero e Cura a Carattere Scientifico, Milano, Italy
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Nakamaru K, Matsumoto K, Taguchi T, Suefuji M, Murata Y, Igata M, Kawashima J, Kondo T, Motoshima H, Tsuruzoe K, Miyamura N, Toyonaga T, Araki E. AICAR, an activator of AMP-activated protein kinase, down-regulates the insulin receptor expression in HepG2 cells. Biochem Biophys Res Commun 2005; 328:449-54. [PMID: 15694368 DOI: 10.1016/j.bbrc.2005.01.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2004] [Indexed: 11/17/2022]
Abstract
The liver is one of the major target organs of insulin in which the expression of insulin receptor is abundant. We analyzed the effect of AICAR, an AMPK activator, on the expression of insulin receptor in a human hepatoma cell line, HepG2 cells. AICAR treatment for 48 h significantly decreased the expression of the insulin receptor protein in a dose-dependent manner, however, this same effect of AICAR was not observed in either 3T3-L1 adipocytes or CHO cells. The expression of insulin receptor mRNA also decreased after AICAR treatment. In addition, the transcriptional activity of the insulin receptor gene promoter investigated with a luciferase assay was down-regulated by AICAR treatment. Dipyridamole, an adenosine transporter inhibitor, and 5'-amino-5'-deoxyadenosine, an adenosine kinase inhibitor, blocked the effect of AICAR on the down-regulation of the insulin receptor protein, mRNA, and promoter activity. Our findings suggest, for the first time, that AMPK activation could reduce the expression of insulin receptor, at least in part, by a down-regulation of the transcriptional level, and this effect may be liver specific.
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Affiliation(s)
- Kazuhiko Nakamaru
- Department of Metabolic Medicine, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan
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De La Vega LA, Stockert RJ. Regulation of the insulin and asialoglycoprotein receptors via cGMP-dependent protein kinase. Am J Physiol Cell Physiol 2000; 279:C2037-42. [PMID: 11078721 DOI: 10.1152/ajpcell.2000.279.6.c2037] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Biotin regulation of asialoglycoprotein receptor expression and insulin receptor activity has been established in two human hepatoblastoma cell lines, Hep G2 and HuH-7. Second messenger cGMP mimics the effect of biotin on asialoglycoprotein receptor expression at the translational level. Metabolic labeling and subsequent immunoprecipitation indicate that the loss of insulin receptor activity during biotin deprivation was due to suppression of receptor synthesis. Evidence for posttranscriptional regulation of insulin receptor synthesis was provided by rapid biotin induction of receptor synthesis without an increase in gene transcript number. Addition of a cGMP-dependent protein kinase (cGK) inhibitor prevented biotin induction of the insulin and asialoglycoprotein receptors, suggesting that protein phosphorylation propagates the cGMP signal transduction cascade. Coatomer protein COPI was recently identified as the trans-acting factor that regulates in vitro translation of the asialoglycoprotein receptor. Biotin repletion of the culture medium resulted in the hyperphosphorylation of alpha-COP, which was prevented by simultaneous addition of the cGK inhibitor. These findings suggest that the end point of this cGMP signal cascade is modulated by cGK and that a phosphorylation reaction governs the expression of both receptor proteins.
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Affiliation(s)
- L A De La Vega
- Marion Bessin Liver Research Center, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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Affiliation(s)
- G Desoye
- Department of Obstetrics and Gynecology, University of Graz, Austria
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cis-acting DNA elements regulating expression of the liver pyruvate kinase gene in hepatocytes and hepatoma cells. Evidence for tissue-specific activators and extinguisher. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(20)89456-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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10
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Rohilla AM, Anderson C, Wood WM, Berhanu P. Insulin downregulates the steady-state level of its receptor's messenger ribonucleic acid. Biochem Biophys Res Commun 1991; 175:520-6. [PMID: 2018500 DOI: 10.1016/0006-291x(91)91595-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of insulin on the steady-state level of human insulin receptor (hIR) mRNA were examined in the HepG2 human liver cell line using Northern blot analysis of either total cellular or poly(A)+ RNA. In control cells, up to six (4.5, 5.2, 7.4, 8.5, 9.4 and 10.8 kb) hybridizable species of hIR mRNA were identified, with the 8.5 and 10.8 kb species being most prominent. Incubation for 18 hrs with 1 microM insulin resulted in a similar decrease (to approximately 35% of control) of all the hIR mRNA species. The insulin effect was dose-dependent and was half-maximal by 2-3 hrs and maximal by 4-6 hrs of incubation at 37 degrees C. The hIR mRNA levels remained maximally insulin suppressed for up to 18 hrs but thereafter the effect became attenuated. These results indicate that insulin downregulates the level of hIR mRNA with a biphasic time-course and that this process is most likely part of the general mechanism by which insulin maintains the homeostatic control of its cellular receptor levels.
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Affiliation(s)
- A M Rohilla
- Department of Medicine, University of Colorado Health Sciences Center, Denver 80262
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Briata P, Bellini C, Vignolo M, Gherzi R. Insulin receptor gene expression is reduced in cells from a progeric patient. Mol Cell Endocrinol 1991; 75:9-14. [PMID: 1646740 DOI: 10.1016/0303-7207(91)90239-o] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We have studied a 15-year-old girl (P1) suffering from the Hutchinson-Gilford syndrome (progeria) associated with a severe insulin resistance. Insulin binding activity to P1 erythrocytes was 85% reduced when compared to that measured in ten normal controls matched for sex and age. This finding was confirmed in Epstein-Barr virus (EBV)-transformed lymphoblasts and depends on a reduction in insulin receptor number. Also the amount of total insulin receptors, [35S]methionine labeled and immunoprecipitated, was 90% reduced in P1 lymphoblasts when compared to controls. Next, we measured insulin receptor mRNA levels and we found undetectable levels of insulin receptor transcript in P1 EBV-transformed lymphoblasts, in the absence of any rearrangement of insulin receptor gene as evaluated by Southern blot analysis. The marked reduction in insulin receptor gene expression probably accounts for the severe insulin resistance presented by the patient. Despite extensive studies, the molecular basis of progeria is still unknown. The near complete absence of a molecule crucial in the transduction of cell growth and differentiation signals could be involved in the accelerated aging of the patient.
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Affiliation(s)
- P Briata
- Laboratories of Immunobiology, National Cancer Institute, Genoa, Italy
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Briata P, Gherzi R. Multifactorial control of insulin receptor gene expression in human cell lines. Biochem Biophys Res Commun 1990; 170:1184-90. [PMID: 1697168 DOI: 10.1016/0006-291x(90)90518-r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Taking advantage of a computer program to align DNA sequences we scanned the 5'-flanking region of the insulin receptor gene to localize putative regulatory elements. Using this approach as a start point, we investigated the effect of several agents on insulin receptor gene expression in human cells. We found that (i) forskolin reduces insulin receptor mRNA levels; (ii) the effects of either forskolin or dexamethasone on insulin receptor mRNA levels are near completely abolished in glucose-starved cells; (iii) 2-mercaptoethanol and heat shock, besides previously described stress conditions (glycosylatyon inhibitors), reduce insulin receptor mRNA levels.
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Affiliation(s)
- P Briata
- Immunobiology Laboratory, National Cancer Institute (I.S.T.), Genova, Italy
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Briata P, Briata L, Gherzi R. Glucose starvation and glycosylation inhibitors reduce insulin receptor gene expression: characterization and potential mechanism in human cells. Biochem Biophys Res Commun 1990; 169:397-405. [PMID: 1694071 DOI: 10.1016/0006-291x(90)90345-n] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Glucose affects the expression of several genes in many cell types. In this work (i) we stably cultured three human cell lines in media containing different glucose concentrations (from 0 to 25 mM), (ii) we characterized glucose effects on insulin receptor gene expression, (iii) we investigated the mechanism by which glucose produces these effects. We found that: (i) glucose starvation reduces insulin receptor gene expression likely affecting insulin receptor gene transcription rates; (ii) a hexose that undergoes to interconversion with glucose metabolites (D-fructose), added to low-glucose media, increases either insulin receptor mRNA levels or insulin binding activity, while hexoses unable to enter the cell (L-glucose) or not metabolizable (3-O-methylglucose), do not produce any effect; (iii) glycosylation inhibitors (2-deoxyglucose and tunicamycin) reduce, in a time-dependent manner, insulin receptor mRNA levels. Our data indicate that glucose affects insulin receptor gene expression in human cells and that protein glycosylation plays a role in this regulatory mechanism.
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MESH Headings
- Blotting, Northern
- Cell Line
- Gene Expression Regulation/drug effects
- Glucose/pharmacology
- Hexoses/pharmacology
- Humans
- Insulin/metabolism
- Insulin-Like Growth Factor I/metabolism
- Kinetics
- RNA/genetics
- RNA/isolation & purification
- RNA, Neoplasm/genetics
- RNA, Neoplasm/isolation & purification
- Receptor, Insulin/biosynthesis
- Receptor, Insulin/genetics
- Receptor, Insulin/metabolism
- Receptors, Cell Surface/metabolism
- Receptors, Somatomedin
- Tumor Cells, Cultured/drug effects
- Tumor Cells, Cultured/metabolism
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Affiliation(s)
- P Briata
- Immunobiology Laboratory, National Cancer Institute (I.S.T.), Genova, Italy
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Briata P, Laurino C, Gherzi R. c-myc gene expression in human cells is controlled by glucose. Biochem Biophys Res Commun 1989; 165:1123-9. [PMID: 2558650 DOI: 10.1016/0006-291x(89)92719-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The c-myc oncogene is implicated in normal growth and differentiation processes. Human cell lines IM9 and HepG2 stably cultured at "low" glucose concentrations (5.5 mM) show c-myc mRNA levels 3-4 times higher than cells cultured at "high" glucose concentrations (25 nM). D-fructose (a metabolizable exose) substitutes for D-glucose in reducing c-myc expression while 3-ortho-methylglucose (a non metabolizable exose) is uneffective. c-myc expression is up-regulated (by PMA) or down-regulated (by dexamethasone and long-term exposure to FCS) in human cells cultured at "low" glucose but not in cells cultured at "high" glucose. We previously demonstrated that insulin receptor gene expression in human cell lines in enhanced by glucose. Therefore, glucose controls in an opposite way the expression of two genes important in the regulation of eukaryotic cell growth and differentiation.
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Affiliation(s)
- P Briata
- Laboratory of Immunobiology, National Cancer Institute I.S.T. Genova, Italy
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