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Gore E, Duparc T, Genoux A, Perret B, Najib S, Martinez LO. The Multifaceted ATPase Inhibitory Factor 1 (IF1) in Energy Metabolism Reprogramming and Mitochondrial Dysfunction: A New Player in Age-Associated Disorders? Antioxid Redox Signal 2022; 37:370-393. [PMID: 34605675 PMCID: PMC9398489 DOI: 10.1089/ars.2021.0137] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Significance: The mitochondrial oxidative phosphorylation (OXPHOS) system, comprising the electron transport chain and ATP synthase, generates membrane potential, drives ATP synthesis, governs energy metabolism, and maintains redox balance. OXPHOS dysfunction is associated with a plethora of diseases ranging from rare inherited disorders to common conditions, including diabetes, cancer, neurodegenerative diseases, as well as aging. There has been great interest in studying regulators of OXPHOS. Among these, ATPase inhibitory factor 1 (IF1) is an endogenous inhibitor of ATP synthase that has long been thought to avoid the consumption of cellular ATP when ATP synthase acts as an ATP hydrolysis enzyme. Recent Advances: Recent data indicate that IF1 inhibits ATP synthesis and is involved in a multitude of mitochondrial-related functions, such as mitochondrial quality control, energy metabolism, redox balance, and cell fate. IF1 also inhibits the ATPase activity of cell-surface ATP synthase, and it is used as a cardiovascular disease biomarker. Critical Issues: Although recent data have led to a paradigm shift regarding IF1 functions, these have been poorly studied in entire organisms and in different organs. The understanding of the cellular biology of IF1 is, therefore, still limited. The aim of this review was to provide an overview of the current understanding of the role of IF1 in mitochondrial functions, health, and diseases. Future Directions: Further investigations of IF1 functions at the cell, organ, and whole-organism levels and in different pathophysiological conditions will help decipher the controversies surrounding its involvement in mitochondrial function and could unveil therapeutic strategies in human pathology. Antioxid. Redox Signal. 37, 370-393.
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Affiliation(s)
- Emilia Gore
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France
| | - Thibaut Duparc
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France
| | - Annelise Genoux
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France.,Service de Biochimie, Pôle de biologie, Hôpital de Purpan, CHU de Toulouse, Toulouse, France
| | - Bertrand Perret
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France.,Service de Biochimie, Pôle de biologie, Hôpital de Purpan, CHU de Toulouse, Toulouse, France
| | - Souad Najib
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France
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2
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Laval M, Dumesny C, Eutick M, Baldwin GS, Marshall KM. Oral trivalent bismuth ions decrease, and trivalent indium or ruthenium ions increase, intestinal tumor burden in Apc Δ14/+ mice. Metallomics 2018; 10:194-200. [PMID: 29296993 DOI: 10.1039/c7mt00272f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Immature forms of the peptide hormone gastrin have been implicated in the development of colorectal cancer (CRC). The biological activity of glycine-extended gastrin (Ggly) is dependent on the binding of Fe3+ ions in vitro and in vivo. The aim of the present study was to determine the effect of blocking Fe3+ ion binding to Ggly, using Bi3+, In3+ or Ru3+ ions, on the development of intestinal tumors in APCΔ14/+ mice. APCΔ14/+ mice were treated orally with Bi3+, In3+ or Ru3+ ions for up to 60 days, serum trace metals were analyzed by inductively coupled plasma mass spectrometry, and the incidence and size of intestinal tumors were assessed. Bi3+ treatment significantly decreased the number of tumors larger than 3 mm in male mice. In3+ or Ru3+ treatment significantly increased the tumor burden in all animals and In3+ increased the number of tumors larger than 3 mm or 5 mm in male mice alone. The fact that binding of In3+ or Ru3+ ions to Ggly was orders of magnitude stronger than the binding of Bi3+ ions implies that the inhibitory effect of Bi3+ ions is not a consequence of a reduction in Ggly activity. However, further testing of higher doses of Bi3+ ions for longer periods as an oral treatment for intestinal tumors is warranted.
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Affiliation(s)
- Marie Laval
- University of Melbourne Department of Surgery, Austin Health, Heidelberg, Victoria, Australia.
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3
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Varga A, Kumar JD, Simpson AWM, Dodd S, Hegyi P, Dockray GJ, Varro A. Cell cycle dependent expression of the CCK2 receptor by gastrointestinal myofibroblasts: putative role in determining cell migration. Physiol Rep 2017; 5:5/19/e13394. [PMID: 29038353 PMCID: PMC5641928 DOI: 10.14814/phy2.13394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 07/27/2017] [Indexed: 01/11/2023] Open
Abstract
The well‐known action of the gastric hormone gastrin in stimulating gastric acid secretion is mediated by activation of cholecystokinin‐2 receptors (CCK2R). The latter are expressed by a variety of cell types suggesting that gastrin is implicated in multiple functions. During wound healing in the stomach CCK2R may be expressed by myofibroblasts. We have now characterized CCK2R expression in cultured myofibroblasts. Immunocytochemistry showed that a relatively small proportion (1–6%) of myofibroblasts expressed the receptor regardless of the region of the gut from which they were derived, or whether from cancer or control tissue. Activation of CCK2R by human heptadecapeptide gastrin (hG17) increased intracellular calcium concentrations in a small subset of myofibroblasts indicating the presence of a functional receptor. Unexpectedly, we found over 80% of cells expressing CCK2R were also labeled with 5‐ethynyl‐2′‐deoxyuridine (EdU) which is incorporated into DNA during S‐phase of the cell cycle. hG17 did not stimulate EdU incorporation but increased migration of both EdU‐labeled and unlabelled myofibroblasts; the migratory response was inhibited by a CCK2R antagonist and by an inhibitor of IGF receptor tyrosine kinase; hG17 also increased IGF‐2 transcript abundance. The data suggest myofibroblasts express CCK2R in a restricted period of the cell cycle during S‐phase, and that gastrin accelerates migration of these cells; it also stimulates migration of adjacent cells probably through paracrine release of IGF. Together with previous findings, the results raise the prospect that gastrin controls the position of dividing myofibroblasts which may be relevant in wound healing and cancer progression in the gastrointestinal tract.
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Affiliation(s)
- Akos Varga
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Jothi Dinesh Kumar
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Alec W M Simpson
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Steven Dodd
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Peter Hegyi
- First Department of Medicine, University of Szeged, Szeged, Hungary.,Institute of Translational Medicine, University of Pecs, Pecs, Hungary
| | - Graham J Dockray
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Andrea Varro
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
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Martinez LO, Genoux A, Ferrières J, Duparc T, Perret B. Serum inhibitory factor 1, high-density lipoprotein and cardiovascular diseases. Curr Opin Lipidol 2017; 28:337-346. [PMID: 28504983 DOI: 10.1097/mol.0000000000000434] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW The atheroprotective properties of HDL are supported by epidemiological and preclinical research. However, the results of interventional trials paradoxically indicate that drugs increasing HDL-cholesterol (HDL-C) do not reduce coronary artery disease (CAD) risk. Moreover, Mendelian randomization studies have shown no effect of HDL-C-modifying variants on CAD outcome. Thus, the protective effects of HDL particles are more governed by their functional status than their cholesterol content. In this context, any successful clinical exploitation of HDL will depend on the identification of HDL-related biomarkers, better than HDL-C level, for assessing cardiovascular risk and monitoring responses to treatment. RECENT FINDINGS Recent studies have enlightened the role of ecto-F1-ATPase as a cell surface receptor for apoA-I, the major apolipoprotein of HDL, involved in the important metabolic and vascular atheroprotective functions of HDL. In the light of these findings, the clinical relevance of ecto-F1-ATPase in humans has recently been supported by the identification of serum F1-ATPase inhibitor (IF1) as an independent determinant of HDL-C, CAD risk and cardiovascular mortality in CAD patients. SUMMARY Serum IF1 measurement might be used as a novel HDL-related biomarker to better stratify risk in high-risk populations or to determine pharmacotherapy.
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Affiliation(s)
- Laurent O Martinez
- aInstitut National de la Santé et de la Recherche Médicale (INSERM), UMR 1048, Institute of Metabolic and Cardiovascular Diseases bUniversity of Toulouse, UMR1048, Paul Sabatier University cService de Biochimie, Pôle biologie, Hôpital de Purpan, CHU de Toulouse dDepartment of Cardiology, Toulouse Rangueil University Hospital eINSERM UMR 1027, Department of Epidemiology, Toulouse University School of Medicine, Toulouse, France
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Laval M, Marshall KM, Sachinidis J, Scott A, Eutick M, Baldwin GS. Complexes of gastrin with In 3+, Ru 3+ or Ga 3+ ions are not recognised by the cholecystokinin 2 receptor. J Biol Inorg Chem 2017; 22:999-1006. [PMID: 28702751 DOI: 10.1007/s00775-017-1478-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 06/21/2017] [Indexed: 11/29/2022]
Abstract
The peptide hormone gastrin (Gamide) binds trivalent metal ions, including indium (In), ruthenium (Ru) and gallium (Ga), with high affinity. Complexes of gastrin with chelated isotopes of In and Ga have previously been used for the location of tumours expressing the cholecystokinin 2 receptor (CCK2R). The aim of the present study was to purify the complexes of Gamide with radioactive isotopes of In, Ru or Ga and to investigate their ability to bind to the CCK2R. The radioactive Gamide complexes were purified on Sep-Pak C18 cartridges or by anion exchange HPLC. Binding to the CCK2R was assessed with a stably transfected clone of the gastric carcinoma cell line AGS. The 106Ru-Gamide complex could be eluted from the C18 cartridge; the 111In-Gamide and 68Ga-Gamide complexes bound irreversibly. All three complexes were successfully purified by anion exchange HPLC. The failure to detect binding of the 111In-Gamide, 106Ru-Gamide and 68Ga-Gamide complexes to the CCK2R suggests that formation of these complexes will not be useful for the detection of tumours expressing this receptor, but may instead provide alternative ways to block the actions of Gamide as a growth factor or a stimulant of gastric acid secretion. The complexes between the hormone gastrin and radioactive 111In, 106Ru or 68Ga ions were purified by anion exchange HPLC using a NaCl gradient. The failure to detect binding of the complexes to the cholecystokinin 2 receptor suggests that metal ion treatment may provide novel approaches to block the biological actions of gastrin.
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Affiliation(s)
- Marie Laval
- Department of Surgery, Austin Health, University of Melbourne, Level 8, Lance Townsend Building, Studley Road, Melbourne, VIC, 3084, Australia.
| | - Kathryn M Marshall
- Department of Surgery, Austin Health, University of Melbourne, Level 8, Lance Townsend Building, Studley Road, Melbourne, VIC, 3084, Australia
| | - John Sachinidis
- Department of Molecular Imaging and Therapy, Austin Health, Melbourne, VIC, Australia
| | - Andrew Scott
- Department of Molecular Imaging and Therapy, Austin Health, Melbourne, VIC, Australia
- Olivia Newton-John Cancer Research Institute, La Trobe University, Melbourne, VIC, Australia
- Department of Medicine, University of Melbourne, Melbourne, VIC, Australia
| | - Mal Eutick
- Phebra Pty. Ltd, Hunters Hill, NSW, Australia
| | - Graham S Baldwin
- Department of Surgery, Austin Health, University of Melbourne, Level 8, Lance Townsend Building, Studley Road, Melbourne, VIC, 3084, Australia
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Marshall KM, Laval M, Sims I, Shulkes A, Baldwin GS. Retro-inverso forms of gastrin5-12 are as biologically active as glycine-extended gastrin in vitro but not in vivo. Peptides 2015; 74:16-22. [PMID: 26471904 DOI: 10.1016/j.peptides.2015.09.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 09/24/2015] [Accepted: 09/29/2015] [Indexed: 01/04/2023]
Abstract
Non-amidated gastrin peptides such as glycine-extended gastrin (Ggly) are biologically active in vitro and in vivo and have been implicated in the development of gastric and colonic cancers. Previous studies have shown that the truncated form of Ggly, the octapeptide LE5AY, was still biologically active in vitro, and that activity was dependent on ferric ion binding but independent of binding to the cholecystokinin 2 (CCK2) receptor. The present work was aimed at creating more stable gastrin-derived 'super agonists' using retro-inverso technology. The truncated LE5AY peptide was synthesized using end protecting groups in three forms with l-amino acids (GL), d-amino acids (GD) or retro-inverso (reverse order with d-amino acids; GRI). All of these peptides bound ferric ions with a 2:1 (Fe: peptide) ratio. As predicted, Ggly, GL and GRI were biologically active in vitro and increased cell proliferation in mouse gastric epithelial (IMGE-5) and human colorectal cancer (DLD-1) cell lines, and increased cell migration in DLD-1 cells. These activities were likely via the same mechanism as Ggly since no CCK1 or CCK2 binding was identified, and GD remained inactive in all assays. Surprisingly, unlike Ggly, GL and GRI were not active in vivo. While Ggly stimulated colonic crypt height and proliferation rates in gastrin knockout mice, GL and GRI did not. The apparent lack of activity may be due to rapid clearance of these smaller peptides. Nevertheless further work designing and testing retro-inverso gastrins is warranted, as it may lead to the generation of super agonists that could potentially be used to treat patients with gastrointestinal disorders with reduced mucosal function.
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Affiliation(s)
- Kathryn M Marshall
- Department of Surgery, University of Melbourne, Austin Health, Lance Townsend Building, Level 8, Studley Road, Heidelberg, Victoria 3084 Australia.
| | - Marie Laval
- Department of Surgery, University of Melbourne, Austin Health, Lance Townsend Building, Level 8, Studley Road, Heidelberg, Victoria 3084 Australia.
| | - Ioulia Sims
- Department of Surgery, University of Melbourne, Austin Health, Lance Townsend Building, Level 8, Studley Road, Heidelberg, Victoria 3084 Australia.
| | - Arthur Shulkes
- Department of Surgery, University of Melbourne, Austin Health, Lance Townsend Building, Level 8, Studley Road, Heidelberg, Victoria 3084 Australia.
| | - Graham S Baldwin
- Department of Surgery, University of Melbourne, Austin Health, Lance Townsend Building, Level 8, Studley Road, Heidelberg, Victoria 3084 Australia.
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Baldwin GS, George GN, Pushie MJ. High Affinity Binding of Indium and Ruthenium Ions by Gastrins. PLoS One 2015; 10:e0140126. [PMID: 26457677 PMCID: PMC4601796 DOI: 10.1371/journal.pone.0140126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 09/21/2015] [Indexed: 11/22/2022] Open
Abstract
The peptide hormone gastrin binds two ferric ions with high affinity, and iron binding is essential for the biological activity of non-amidated forms of the hormone. Since gastrins act as growth factors in gastrointestinal cancers, and as peptides labelled with Ga and In isotopes are increasingly used for cancer diagnosis, the ability of gastrins to bind other metal ions was investigated systematically by absorption spectroscopy. The coordination structures of the complexes were characterized by extended X-ray absorption fine structure (EXAFS) spectroscopy. Changes in the absorption of gastrin in the presence of increasing concentrations of Ga3+ were fitted by a 2 site model with dissociation constants (Kd) of 3.3 x 10−7 and 1.1 x 10−6 M. Although the absorption of gastrin did not change upon the addition of In3+ ions, the changes in absorbance on Fe3+ ion binding in the presence of indium ions were fitted by a 2 site model with Kd values for In3+ of 6.5 x 10−15 and 1.7 x 10−7 M. Similar results were obtained with Ru3+ ions, although the Kd values for Ru3+ of 2.6 x 10−13 and 1.2 x 10−5 M were slightly larger than observed for In3+. The structures determined by EXAFS all had metal:gastrin stoichiometries of 2:1 but, while the metal ions in the Fe, Ga and In complexes were bridged by a carboxylate and an oxygen with a metal-metal separation of 3.0–3.3 Å, the Ru complex clearly demonstrated a short range Ru—Ru separation, which was significantly shorter, at 2.4 Å, indicative of a metal-metal bond. We conclude that gastrin selectively binds two In3+ or Ru3+ ions, and that the affinity of the first site for In3+ or Ru3+ ions is higher than for ferric ions. Some of the metal ion-gastrin complexes may be useful for cancer diagnosis and therapy.
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Affiliation(s)
- Graham S. Baldwin
- The University of Melbourne Department of Surgery, Austin Health, Heidelberg, Victoria 3084, Australia
- * E-mail:
| | - Graham N. George
- Molecular and Environmental Science Research Group Department of Geological Sciences, 114 Science Place, University of Saskatchewan, Saskatoon, S7N 5E2, Canada
| | - M. Jake Pushie
- Molecular and Environmental Science Research Group Department of Geological Sciences, 114 Science Place, University of Saskatchewan, Saskatoon, S7N 5E2, Canada
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Rehfeld JF. Do glycine-extended hormone precursors have clinical significance? INTERNATIONAL JOURNAL OF ENDOCRINE ONCOLOGY 2014. [DOI: 10.2217/ije.14.14] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Half of the known peptide hormones are C-terminally amidated. Subsequent biogenesis studies have shown that the immediate precursor is a glycine-extended peptide. The clinical interest in glycine-extended hormones began in 1994, when it was suggested that glycine-extended gastrin stimulated cancer cell growth. Accompanying findings of gastrin gene expression in common cancers spurred the interest. The interest is now accompanied by skepticism, which is due to failure to demonstrate truly specific receptors for glycine-extended peptides and failure to demonstrate separate physiological and clinical effects of glycine-extended precursors for most other amidated hormones than gastrin and cholecystokinin (CCK). The idea of glycine-extended peptides as independent messengers was interesting. But clinical science has to move ahead from ideas that cannot be supported at key points after decades of research.
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Najib S, Kowalski-Chauvel A, Do C, Roche S, Cohen-Jonathan-Moyal E, Seva C. Progastrin a new pro-angiogenic factor in colorectal cancer. Oncogene 2014; 34:3120-30. [DOI: 10.1038/onc.2014.255] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 06/25/2014] [Accepted: 07/03/2014] [Indexed: 01/02/2023]
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Abstract
The existence of the hormone gastrin in the distal stomach (antrum) has been known for almost 110 years, and the physiological function of this amidated peptide in regulating gastric acid secretion via the CCK2 receptor is now well established. In this brief review we consider important additional roles of gastrin, including regulation of genes encoding proteins such as plasminogen activator inhibitors and matrix metalloproteinases that have important actions on extracellular matrix remodelling. These actions are, at least in part, effected by paracrine signalling pathways and make important contributions to maintaining functional integrity of the gastric epithelium. Recent studies also provide support for the idea that gastrin, in concert with other hormones, could potentially contribute a post-prandial incretin effect. We also review recent developments in the biology of other gastrin gene products, including the precursor progastrin, which causes proliferation of the colonic epithelium and in certain circumstances may induce cancer formation. Glycine-extended biosynthetic processing intermediates also have proliferative effects in colonic mucosa and in some oesophageal cancer cell lines. Whether these additional gene products exert their effects through the CCK2 receptor or a separate entity is currently a matter of debate.
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Affiliation(s)
- Rod Dimaline
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool L69 3BX, UK
| | - Andrea Varro
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool L69 3BX, UK
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Xiao L, Kovac S, Chang M, Shulkes A, Baldwin GS, Patel O. Zinc ions upregulate the hormone gastrin via an E-box motif in the proximal gastrin promoter. J Mol Endocrinol 2014; 52:29-42. [PMID: 24363439 DOI: 10.1530/jme-13-0162] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Gastrin and its precursors act as growth factors for the normal and neoplastic gastrointestinal mucosa. As the hypoxia mimetic cobalt chloride upregulates the gastrin gene, the effect of other metal ions on gastrin promoter activity was investigated. Gastrin mRNA was measured by real-time PCR, gastrin peptides by RIA, and gastrin promoter activity by dual-luciferase reporter assay. Exposure to Zn(2)(+) ions increased gastrin mRNA concentrations in the human gastric adenocarcinoma cell line AGS in a dose-dependent manner, with a maximum stimulation of 55 ± 14-fold at 100 μM (P<0.05). Significant stimulation was also observed with Cd(2)(+) and Cu(2)(+), but not with Ca(2)(+), Mg(2)(+), Ni(2)(+), or Fe(3)(+) ions. Activation of MAPK and phosphatidylinositol 3-kinase pathways is necessary but not sufficient for gastrin induction by Zn(2)(+). Deletional mutation of the gastrin promoter identified an 11 bp DNA sequence, which contained an E-box motif, as necessary for Zn(2)(+)-dependent gastrin induction. The fact that E-box binding transcription factors play a crucial role in the epithelial-mesenchymal transition (EMT), together with our observation that Zn(2)(+) ions upregulate the gastrin gene in AGS cells by an E-box-dependent mechanism, suggests that Zn(2)(+) ions may induce an EMT, and that gastrin may be involved in the transition.
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Affiliation(s)
- Lin Xiao
- Department of Surgery, Austin Health, The University of Melbourne, Studley Road, Heidelberg, Victoria 3084, Australia
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Piccoli S, Suku E, Garonzi M, Giorgetti A. Genome-wide Membrane Protein Structure Prediction. Curr Genomics 2013; 14:324-9. [PMID: 24403851 PMCID: PMC3763683 DOI: 10.2174/13892029113149990009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 07/19/2013] [Accepted: 07/22/2013] [Indexed: 01/25/2023] Open
Abstract
Transmembrane proteins allow cells to extensively communicate with the external world in a very accurate and specific way. They form principal nodes in several signaling pathways and attract large interest in therapeutic intervention, as the majority pharmaceutical compounds target membrane proteins. Thus, according to the current genome annotation methods, a detailed structural/functional characterization at the protein level of each of the elements codified in the genome is also required. The extreme difficulty in obtaining high-resolution three-dimensional structures, calls for computational approaches. Here we review to which extent the efforts made in the last few years, combining the structural characterization of membrane proteins with protein bioinformatics techniques, could help describing membrane proteins at a genome-wide scale. In particular we analyze the use of comparative modeling techniques as a way of overcoming the lack of high-resolution three-dimensional structures in the human membrane proteome.
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Affiliation(s)
- Stefano Piccoli
- Applied Bioinformatics Group, Dept. of Biotechnology, University of Verona, strada Le grazie 15, 37134, Verona,
Italy
| | - Eda Suku
- Applied Bioinformatics Group, Dept. of Biotechnology, University of Verona, strada Le grazie 15, 37134, Verona,
Italy
| | - Marianna Garonzi
- Applied Bioinformatics Group, Dept. of Biotechnology, University of Verona, strada Le grazie 15, 37134, Verona,
Italy
| | - Alejandro Giorgetti
- Applied Bioinformatics Group, Dept. of Biotechnology, University of Verona, strada Le grazie 15, 37134, Verona,
Italy
- German Research School for Simulation Sciences, Juelich, Germany
- Center for Biomedical Computing (CBMC), University of Verona, strada Le grazie 8, 37134, Verona, Italy
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