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Kilberg MS, Pan YX, Chen H, Leung-Pineda V. Nutritional control of gene expression: how mammalian cells respond to amino acid limitation. Annu Rev Nutr 2005; 25:59-85. [PMID: 16011459 PMCID: PMC3600373 DOI: 10.1146/annurev.nutr.24.012003.132145] [Citation(s) in RCA: 206] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The amino acid response (AAR) pathway in mammalian cells is designed to detect and respond to amino acid deficiency. Limiting any essential amino acid initiates this signaling cascade, which leads to increased translation of a "master regulator," activating transcription factor (ATF) 4, and ultimately, to regulation of many steps along the pathway of DNA to RNA to protein. These regulated events include chromatin remodeling, RNA splicing, nuclear RNA export, mRNA stabilization, and translational control. Proteins that are increased in their expression as targets of the AAR pathway include membrane transporters, transcription factors from the basic region/leucine zipper (bZIP) superfamily, growth factors, and metabolic enzymes. Significant progress has been achieved in understanding the molecular mechanisms by which amino acids control the synthesis and turnover of mRNA and protein. Beyond gaining additional knowledge of these important regulatory pathways, further characterization of how these processes contribute to the pathology of various disease states represents an interesting aspect of future research in molecular nutrition.
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Affiliation(s)
- M S Kilberg
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, Florida 32610-0245, USA.
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Claeyssens S, Gangneux C, Brasse-Lagnel C, Ruminy P, Aki T, Lavoinne A, Salier JP. Amino acid control of the human glyceraldehyde 3-phosphate dehydrogenase gene transcription in hepatocyte. Am J Physiol Gastrointest Liver Physiol 2003; 285:G840-9. [PMID: 12842822 DOI: 10.1152/ajpgi.00060.2003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Glutamine (Gln) is the most potent of the amino acids (AAs) that regulate liver anabolism, and its effect is similar to that of insulin in peripheral tissues. However, the influence of AAs on regulation of metabolic enzyme-encoding genes is not known at the molecular level in liver. We now report that Gln and some essential AAs activate the human GAPDH gene that codes for GAPDH, a central enzyme of glycolysis and a target for insulin regulation. In HepG2 cells, Gln upregulated the GAPDH mRNA level, and this effect was additive to that of insulin. Transient transfection of GAPDH promoter/cat constructs demonstrated that a gene-specific and insulin-independent transcriptional step is involved in the Gln responsiveness of GAPDH. Transfected HepG2 cells challenged with various AAs, Gln metabolites or inhibitors of Gln metabolism showed that the Gln-induced effect is similar to that of some essential AAs and that Gln metabolism is a necessary step for GAPDH activation. Deletion mutants and site-directed mutagenesis of the GAPDH promoter indicated that the Gln responsiveness is mediated by a sequence that is distinct from insulin-responsive elements and from positively acting elements previously described in this promoter. This motif located at -126/-118 clearly differs from AA-responsive elements recently identified in other genes. Electromobility shift assay and supershifts showed that the transcription factors bound to the Gln-responsive element in the GAPDH promoter are C/EBPalpha and -delta. This finding is consistent with the role of C/EBP family members in controlling the hepatic expression of genes involved in nutrient metabolism.
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Affiliation(s)
- Sophie Claeyssens
- Faculté de Médecine-Pharmacie, 22 Bvd Gambetta, 76183 Rouen cedex, France.
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Berk JL, Hatch CA, Goldstein RH. Hypoxia inhibits amino acid uptake in human lung fibroblasts. J Appl Physiol (1985) 2000; 89:1425-31. [PMID: 11007578 DOI: 10.1152/jappl.2000.89.4.1425] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hypoxia and amino acid deprivation downregulate expression of extracellular matrix genes in lung fibroblasts. We examined the effect of hypoxia on amino acid uptake and protein formation in human lung fibroblasts. Low O(2) tension (0% O(2)) suppressed incorporation of [(3)H]proline into type I collagen without affecting [(35)S]methionine labeling of other proteins. Initial decreases in intracellular [(3)H]proline incorporation occurred after 2 h of exposure to 0% O(2), with maximal suppression of intracellular [(3)H]proline levels at 6 h of treatment. Hypoxia significantly inhibited the uptake of radiolabeled proline, 2-aminoisobutyric acid (AIB), and 2-(methylamino)isobutyric acid (methyl-AIB) while inducing minor decreases in leucine transport. Neither cycloheximide nor indomethacin abrogated hypoxia-related suppression of methyl-AIB uptake. Efflux studies demonstrated that hypoxia inhibited methyl-AIB transport in a bidirectional fashion. The downregulation of amino acid transport was not due to a toxic effect; function recovered on return to standard O(2) conditions. Kinetic analysis of AIB transport revealed a 10-fold increase in K(m) accompanied by a small increase in maximal transport velocity among cells exposed to 0% O(2). These data indicate that low O(2) tension regulates the system A transporter by decreasing transporter substrate affinity.
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Affiliation(s)
- J L Berk
- The Pulmonary Center, Boston University School of Medicine, and Boston Veterans Affairs Medical Center, Boston, Massachusetts 02118, USA.
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Paul GL, Waegner A, Gaskins HR, Shay NF. Histidine availability alters glucagon gene expression in murine alphaTC6 cells. J Nutr 1998; 128:973-6. [PMID: 9614156 DOI: 10.1093/jn/128.6.973] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Because individual amino acids (AA) stimulate glucagon release from pancreatic alpha-cells, the purpose of this study was to determine if individual AA could influence glucagon gene expression. Preproglucagon mRNA levels were 67% lower (P < 0.05) in mouse alphaTC6 cells incubated for 12 h in amino acid-free medium compared with cells incubated in complete medium containing all 20 AA. A time-course study indicated that alphaTC6 cells incubated in amino acid-free medium +/-1 micromol/L puromycin or amino acid-containing medium plus puromycin exhibited similar preproglucagon mRNA decreases over 12 h. When 1 micromol/L actinomycin was added to medium with or without AA, ppG mRNA concentrations decreased (P < 0.05) for 3h; however, values at 12 h were not different than those at 3 h. Deletions of single AA from complete medium demonstrated that only histidine removal or depletion reproduced the decrease in ppG mRNA observed in amino acid-free medium. We conclude that histidine is involved in the regulation of preproglucagon mRNA levels in alphaTC6 cells and that this regulation may be operative during both transcriptional and post-transcriptional events.
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Affiliation(s)
- G L Paul
- Department of Food Science and Human Nutrition, and Division of Nutritional Sciences, University of Illinois, Urbana-Champaign, IL 61801, USA
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Matthews JC, Beveridge MJ, Malandro MS, Kilberg MS, Novak DA. Response of placental amino acid transport to gestational age and intrauterine growth retardation. Proc Nutr Soc 1998; 57:257-63. [PMID: 9656329 DOI: 10.1079/pns19980040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- J C Matthews
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville 32610-0296, USA
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6
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Partial sequences of two genes regulated by amino acid supply identified by the use of RNA fingerprinting by arbitrarily primed PCR. J Nutr Biochem 1998. [DOI: 10.1016/s0955-2863(97)00175-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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7
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Ferrer-Martínez A, Felipe A, Mata JF, Casado FJ, Pastor-Anglada M. Molecular cloning of a bovine renal G-protein coupled receptor gene (bRGR): regulation of bRGR mRNA levels by amino acid availability. Biochem Biophys Res Commun 1997; 238:107-12. [PMID: 9299461 DOI: 10.1006/bbrc.1997.7185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A cDNA of 3.2 kb, encoding a putative G protein-coupled receptor and hence called bRGR1, has been isolated from a cDNA library generated from the bovine renal epithelial cell line NBL-1. This cDNA consisted of 41 base pairs of 5'-untranslated sequence, an open reading frame of 1083 base pairs, and a 2.07 kb fragment of 3'-untranslated sequence that includes a poly(dA) tail. The coding sequence predicts a protein of 361 residues. The ligand of the bRGR1 protein may be of low molecular weight, as deduced from the analysis of the predicted primary structure of the receptor protein and the comparison with other subtypes of the G protein-coupled receptor family. The amounts of bRGR1 mRNA significantly increase when NBL-1 cells are cultured in an amino acid-depleted medium. This effect can not be caused by a decrease in protein synthesis because cycloheximide did not mimic the increase in bRGR1 mRNA levels triggered by amino acid starvation. These data suggest that bRGR1 may be an amino acid-regulated gene.
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Affiliation(s)
- A Ferrer-Martínez
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Spain
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Krupsky M, Kuang PP, Goldstein RH. Regulation of type I collagen mRNA by amino acid deprivation in human lung fibroblasts. J Biol Chem 1997; 272:13864-8. [PMID: 9153245 DOI: 10.1074/jbc.272.21.13864] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The steady state levels of alpha1(I) collagen mRNA are decreased by retinoic acid and prostaglandin E2. These effector substances decrease the uptake of A system amino acids. We examined the effect of amino acid deprivation on the steady state levels of alpha1(I) collagen in human lung fibroblasts. Maintenance of fibroblasts in amino acid-free medium decreased alpha1(I) collagen mRNA levels by 29% at 24 h and 78% at 72 h. Frequent refeeding of cultures with amino acid-free medium resulted in more rapid decreases in intracellular amino acids and in alpha1(I) collagen mRNA levels. The decrease in alpha1(I) collagen mRNA levels was mediated by decreases in mRNA stability as assessed by a half-life determination using actinomycin D and by decreases in the rate of transcription as assessed by nuclear run-on assay. Treatment of fibroblasts with medium containing amino acids resulted in rapid restoration of alpha1(I) collagen mRNA levels. This increase in alpha1(I) collagen mRNA expression required protein synthesis as determined by cycloheximide sensitivity and was inhibited by prostaglandin E2. These data indicate that alpha1(I) collagen mRNA levels are sensitive to alterations in the amount of intracellular amino acids and suggest a potential mechanism whereby alpha1(I) collagen accumulation may be regulated independent of inflammatory mediators following lung injury.
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Affiliation(s)
- M Krupsky
- Pulmonary Center and the Department of Biochemistry, Boston University School of Medicine and the Boston Veterans Affairs Medical Center, Boston, Massachusetts 02118, USA
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Hutson RG, Warskulat U, Häussinger D, Kilberg MS. An example of nutrient control of gene expression: amino acid-dependent regulation of asparagine synthetase. Clin Nutr 1996; 15:327-31. [PMID: 16844066 DOI: 10.1016/s0261-5614(96)80009-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Amino acid deprivation of mammalian cells causes a significant enhancement in gene expression for a number of important cellular activities, among these is included asparagine synthetase (AS). A full length cDNA clone for rat AS was isolated previously from a subtracted cDNA library enriched for amino acid-regulated sequences. The present report summarizes the use of the AS cDNA to investigate the amino acid-dependent regulation of AS mRNA in normal rat liver and Fao hepatoma cells. In response to complete amino acid starvation, there was an increase in steady state AS mRNA content. Three species of mRNA, approximately 2.0, 2.5 and 4.0 kb, were detected and each was simultaneously regulated to the same degree. In hepatoma cells the increased AS mRNA content was prevented by either actinomycin D or cycloheximide. Partial repression of the AS mRNA content was maintained by the presence of a single amino acid in the culture medium, but the effectiveness varied. Glutamine effectively repressed the AS mRNA content, even at a concentration 10 times below its plasma level. Conversely, depletion of selected single amino acids from complete culture medium also caused up-regulation. A role for tRNA charging in the signalling mechanism was suggested by the observation that the addition of histidinol, an inhibitor of histidinyl tRNA synthetase, caused an increase in AS mRNA content when added to complete medium. The increased AS mRNA is associated with polysomes and is actively translated. The data indicate that nutrient regulation of the rat AS gene occurs by a general control mechanism that is responsive to the availability of selected individual amino acids.
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Affiliation(s)
- R G Hutson
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Box 100245, JHMHC,Gainesville, Florida 32610-0245, USA
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Laine RO, Hutson RG, Kilberg MS. Eukaryotic gene expression: metabolite control by amino acids. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1996; 53:219-48. [PMID: 8650304 DOI: 10.1016/s0079-6603(08)60146-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Our understanding of the metabolite control in mammalian cells lags far behind that in prokaryotes. This is particularly true for amino-acid-dependent gene expression. Few proteins have been identified for which synthesis is selectively regulated by amino-acid availability, and the mechanisms for control of transcription and translation in response to changes in amino-acid availability have not yet been elucidated. The intimate relationship between amino-acid supply and the fundamental cellular process of protein synthesis makes amino-acid-dependent control of gene expression particularly important. Future studies should provide important insight into amino-acid and other nutrient signaling pathways, and their impact on cellular growth and metabolism.
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Affiliation(s)
- R O Laine
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville 32610, USA
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Franěk F, Chládková-Šrámková K. Apoptosis and nutrition: Involvement of amino acid transport system in repression of hybridoma cell death. Cytotechnology 1995; 18:113-7. [DOI: 10.1007/bf00744326] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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12
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Sell SM, Reese D, Ossowski VM. Insulin-inducible changes in insulin receptor mRNA splice variants. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)47346-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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13
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Laine R, Shay N, Kilberg M. Nuclear retention of the induced mRNA following amino acid-dependent transcriptional regulation of mammalian ribosomal proteins L17 and S25. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)36938-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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14
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Hann SR, Sloan-Brown K, Spotts GD. Translational activation of the non-AUG-initiated c-myc 1 protein at high cell densities due to methionine deprivation. Genes Dev 1992; 6:1229-40. [PMID: 1628829 DOI: 10.1101/gad.6.7.1229] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
c-myc belongs to a small, yet growing, group of eukaryotic mRNAs that initiate translation inefficiently from a non-AUG codon upstream from a more efficient AUG codon. We have examined the translational regulation of non-AUG-initiated c-myc 1 and AUG-initiated c-myc 2 protein synthesis in avian and mouse cells during proliferation. As lymphoid, erythroid, and embryo fibroblast cells approached high densities in culture, there was a sustained 5- to 10-fold induction in the synthesis of c-myc 1 protein to levels greater than or equal to c-myc 2 protein synthesis. Treatment with conditioned/depleted media from high-density cells was able to reproduce this activation in low-density cells within 5 hr. Additional studies with the conditioned/depleted media revealed that amino acid availability, specifically methionine deprivation, was responsible for this unique translational control. Our results describe a specific and dramatic regulation of dual translational initiation. Furthermore, these results represent a novel translational activation of a specific gene in higher eukaryotes in response to nutrient deprivation.
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Affiliation(s)
- S R Hann
- Department of Cell Biology, Vanderbilt University, School of Medicine, Nashville, Tennessee 37232-2175
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15
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Taylor P, Mackenzie B, Low S, Rennie M. Expression of rat liver glutamine transporters in Xenopus laevis oocytes. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)50607-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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16
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Identification of an amino acid-regulated mRNA from rat liver as the mammalian equivalent of bacterial ribosomal protein L22. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(19)47324-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Cheeseman CI. Molecular mechanisms involved in the regulation of amino acid transport. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1991; 55:71-84. [PMID: 1871316 DOI: 10.1016/0079-6107(91)90001-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- C I Cheeseman
- Department of Physiology, University of Alberta, Edmonton, Canada
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