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Zhelyaznik N, Mey J. Regulation of retinoic acid receptors alpha, beta and retinoid X receptor alpha after sciatic nerve injury. Neuroscience 2006; 141:1761-74. [PMID: 16782282 DOI: 10.1016/j.neuroscience.2006.05.021] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2005] [Revised: 05/09/2006] [Accepted: 05/10/2006] [Indexed: 11/15/2022]
Abstract
Cell culture experiments indicated that activation of the retinoic acid signaling system is involved in axonal regeneration. This hypothesis was tested with sciatic nerve injury in the rat. Since the effect of retinoic acid is mediated via retinoic acid receptors and retinoid X receptors, we investigated mRNA and protein expression of these receptors during injury-induced degeneration and regeneration. Seven days after crush injury, transcript concentrations of all retinoic acid receptors and of retinoid X receptor alpha were significantly higher than in non-lesioned nerves. Protein levels of retinoic acid receptor alpha, retinoic acid receptor beta and retinoid X receptor alpha were upregulated 4, 7 and 14 days after injury. In degenerating nerves a significant increase of retinoic acid receptor alpha was detected 7 and 14 days, and of retinoic acid receptor beta 14 and 21 days after complete transection. Immunohistochemical staining of retinoid receptors revealed their expression in Schwann cells and macrophages. In addition, we observed that retinoic acid receptor alpha and retinoid X receptor alpha appeared in the cell nuclei of macrophages during the lesion-induced inflammatory reaction, and that retinoid X receptor alpha-staining co-localized with some regenerating axons. Experiments with Schwann cell primary cultures revealed an effect of retinoic acid on the expression of the neuregulin receptor ErbB3, suggesting that one function of retinoic acid consists in the regulation of neuroglial interactions after peripheral nerve injury.
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MESH Headings
- Animals
- Animals, Newborn
- Blotting, Northern/methods
- Blotting, Western/methods
- Cells, Cultured
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/physiology
- Immunohistochemistry/methods
- Macrophages/drug effects
- Macrophages/metabolism
- Male
- RNA, Messenger/biosynthesis
- Rats
- Rats, Sprague-Dawley
- Receptor, Nerve Growth Factor/genetics
- Receptor, Nerve Growth Factor/metabolism
- Receptors, Retinoic Acid/classification
- Receptors, Retinoic Acid/genetics
- Receptors, Retinoic Acid/metabolism
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Schwann Cells/drug effects
- Schwann Cells/metabolism
- Sciatic Neuropathy/metabolism
- Sciatic Neuropathy/physiopathology
- Time Factors
- Tretinoin/pharmacology
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Affiliation(s)
- N Zhelyaznik
- Institut für Biologie II, RWTH Aachen, Kopernikusstrasse 16, 52074 Aachen, Germany
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202
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Bry K, Lappalainen U. Pathogenesis of bronchopulmonary dysplasia: the role of interleukin 1beta in the regulation of inflammation-mediated pulmonary retinoic acid pathways in transgenic mice. Semin Perinatol 2006; 30:121-8. [PMID: 16813970 DOI: 10.1053/j.semperi.2006.04.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Pulmonary inflammation, increased production of the inflammatory cytokine interleukin-1beta (IL-1beta), and vitamin A deficiency are risk factors for the development of bronchopulmonary dysplasia (BPD) in premature infants. To determine the mechanisms by which IL-1beta influences lung development, we have generated transgenic mice in which human IL-1beta is expressed in the lung epithelium with a doxycycline-inducible system controlled by the Clara cell secretory protein promoter. Perinatal IL-1beta production in these mice causes a phenotype that is strikingly similar to BPD. Pulmonary pathology in the mice shows inflammation, lack of alveolar septation, and impaired vascular development of the lung, similar to the histological characteristics of BPD. Retinoic acid (RA), one of the most biologically active derivatives of vitamin A, increases septation. Proteins involved in mediating the cellular responses to RA include the cellular retinoic acid binding proteins CRABP-I and CRABP-II and the nuclear retinoic acid receptors RAR-alpha, RAR-beta, and RAR-gamma. OBJECTIVE To test the hypothesis that IL-1beta inhibits the expression of proteins involved in mediating the cellular response to RA. METHODS The mRNA expression of CRABP-I, CRABP-II, RAR-alpha1, RAR-beta2, RAR-beta4, and RAR-gamma2 was studied with real-time RT-PCR on gestational day 18, and postnatal days 0, 1, 5, and 7 in IL-1beta-expressing mice and their control littermates. In addition, immunohistochemistry for CRABP-I was performed. RESULTS IL-1beta decreased the mRNA expression and protein production of CRABP-I as well as the mRNA expression of RAR-gamma2. In contrast, no differences between IL-1beta-expressing and control mice were detected in the expression of CRABP-II, RAR-alpha1, RAR-beta2, or RAR-beta4. CONCLUSION The present study demonstrates for the first time a link between inflammation and the retinoic acid pathway. Inhibition of CRABP-I and RAR-gamma2 expression may be one mechanism by which inflammation prevents alveolar septation. The therapeutic potential of RA in promoting septation in the setting of perinatal lung inflammation deserves further investigation.
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Affiliation(s)
- Kristina Bry
- Department of Pediatrics, Göteborg University, The Queen Silvia Children's Hospital, 41685 Göteborg, Sweden.
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203
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Tozaki-Saitoh H, Koizumi S, Sato Y, Tsuda M, Nagao T, Inoue K. Retinoic acids increase P2X2 receptor expression through the 5'-flanking region of P2rx2 gene in rat phaeochromocytoma PC-12 cells. Mol Pharmacol 2006; 70:319-28. [PMID: 16638968 DOI: 10.1124/mol.105.020511] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The P2X2 receptor is a subtype of ionotropic ATP receptor and plays a significant role in regulating fast synaptic transmission in the nervous system. Because the expression level of the P2X2 receptor is known to determine its channel properties and functional interactions with other neurotransmitter channels, elucidating the mechanisms underlying the regulation of P2X2 receptor expression in neuronal cells is important. Here, we identified three motifs that correspond to the retinoic acid response element in the 5'-flanking region of the rat P2X2 gene. In rat pheochromocytoma PC-12 cells, treatment with 9-cis-retinoic acid as well as all-trans-retinoic acid significantly increased the mRNA and protein level of P2X2 receptor. In addition, in PC-12 cells transiently transfected with a luciferase reporter gene driven by the promoter region of the rat P2X2 gene, both 9-cis-retinoic acid and all-trans-retinoic acid increased the luciferase activity, whereas their effects were diminished by truncation of the retinoic acid response elements in the promoter. Furthermore, 9-cis-retinoic acid enhanced the ATP-evoked whole cell currents and intracellular Ca2+- and ATP-evoked dopamine release, indicating the up-regulation of functional P2X2 receptors on the plasma membrane. These results provide the molecular mechanism underlying the transcriptional regulation of P2X2 receptors and suggest that retinoid is an important factor in regulating P2X2 receptors in the nervous system.
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Affiliation(s)
- Hidetoshi Tozaki-Saitoh
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi, Fukuoka 812-8582, Japan
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204
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Njar VCO, Gediya L, Purushottamachar P, Chopra P, Vasaitis TS, Khandelwal A, Mehta J, Huynh C, Belosay A, Patel J. Retinoic acid metabolism blocking agents (RAMBAs) for treatment of cancer and dermatological diseases. Bioorg Med Chem 2006; 14:4323-40. [PMID: 16530416 DOI: 10.1016/j.bmc.2006.02.041] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2006] [Revised: 02/21/2006] [Accepted: 02/22/2006] [Indexed: 11/23/2022]
Abstract
The naturally occurring retinoids and their synthetic analogs play a key role in differentiation, proliferation, and apoptosis, and their use/potential in oncology, dermatology and a variety of diseases are well documented. This review focuses on the role of all-trans-retinoic acid (ATRA), the principal endogenous metabolite of vitamin A (retinol) and its metabolism in oncology and dermatology. ATRA has been used successfully in differentiated therapy of acute promyelocytic leukemia, skin cancer, Kaposi's sarcoma, and cutaneous T-cell lymphoma, and also in the treatment of acne and psoriasis. However, its usefulness is limited by the rapid emergence of acquired ATRA resistance involving multifactoral mechanisms. A key mechanism of resistance involves ATRA-induced catabolism of ATRA. Thus, a novel strategy to overcome the limitation associated with exogenous ATRA therapy has been to modulate and/or increase the levels of endogenous ATRA by inhibiting the cytochrome P450-dependent ATRA-4-hydroxylase enzymes (particularly CYP26s) responsible for ATRA metabolism. These inhibitors are also referred to as retinoic acid metabolism blocking agents (RAMBAs). This review highlights development in the design, synthesis, and evaluation of RAMBAs. Major emphasis is given to liarozole, the most studied and only RAMBA in clinical use and also the new RAMBAs in development and with clinical potential.
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Affiliation(s)
- Vincent C O Njar
- Department of Pharmacology and Experimental Therapeutics, University of Maryland School of Medicine, Baltimore, 21201-1559, USA.
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205
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Wang T, Montell C. Rhodopsin formation in Drosophila is dependent on the PINTA retinoid-binding protein. J Neurosci 2006; 25:5187-94. [PMID: 15917458 PMCID: PMC6724816 DOI: 10.1523/jneurosci.0995-05.2005] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Retinoids participate in many essential processes including the initial event in photoreception. 11-cis-retinal binds to opsin and undergoes a light-driven isomerization to all-trans-retinal. In mammals, the all-trans-retinal is converted to vitamin A (all-trans-retinol) and is transported to the retinal pigment epithelium (RPE), where along with dietary vitamin A, it is converted into 11-cis-retinal. Although this cycle has been studied extensively in mammals, many questions remain, including the specific roles of retinoid-binding proteins. Here, we establish the Drosophila visual system as a genetic model for characterizing retinoid-binding proteins. In a genetic screen for mutations that affect the biosynthesis of rhodopsin, we identified a novel CRAL-TRIO domain protein, prolonged depolarization afterpotential is not apparent (PINTA), which binds to all-trans-retinol. We demonstrate that PINTA functions subsequent to the production of vitamin A and is expressed and required in the retinal pigment cells. These results represent the first genetic evidence for a role for the retinal pigment cells in the visual response. Moreover, our data implicate Drosophila retinal pigment cells as functioning in the conversion of dietary all-trans-retinol to 11-cis-retinal and suggest that these cells are the closest invertebrate equivalent to the RPE.
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Affiliation(s)
- Tao Wang
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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206
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Mey J. New therapeutic target for CNS injury? The role of retinoic acid signaling after nerve lesions. ACTA ACUST UNITED AC 2006; 66:757-79. [PMID: 16688771 DOI: 10.1002/neu.20238] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Experiments with sciatic nerve lesions and spinal cord contusion injury demonstrate that the retinoic acid (RA) signaling cascade is activated by these traumatic events. In both cases the RA-synthesizing enzyme is RALDH-2. In the PNS, lesions cause RA-induced gene transcription, intracellular translocation of retinoid receptors, and increased transcription of CRBP-I, CRABP-II, and retinoid receptors. The activation of RARbeta appears to be responsible for neurotrophic and neuritogenic effects of RA on dorsal root ganglia and embryonic spinal cord. While the physiological role of RA in the injured nervous system is still under investigation three domains of functions are suggested: (1) neuroprotection and support of axonal growth, (2) modulation of the inflammatory reaction by microglia/macrophages, and (3) regulation of glial differentiation. Few studies have been performed to support nerve regeneration with RA signals in vivo, but a large number of experiments with neuronal and glial cell cultures and spinal cord explants point to beneficial effects of RA, so that future therapeutic approaches will likely focus on the activation of RA signaling.
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Affiliation(s)
- Jörg Mey
- Institut für Biologie II, RWTH Aachen, Germany.
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207
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Hoegberg P, Schmidt CK, Fletcher N, Nilsson CB, Trossvik C, Gerlienke Schuur A, Brouwer A, Nau H, Ghyselinck NB, Chambon P, Håkansson H. Retinoid status and responsiveness to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in mice lacking retinoid binding protein or retinoid receptor forms. Chem Biol Interact 2005; 156:25-39. [PMID: 16109390 DOI: 10.1016/j.cbi.2005.06.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2005] [Revised: 06/16/2005] [Accepted: 06/27/2005] [Indexed: 11/15/2022]
Abstract
We have investigated the role of Vitamin A (retinoid) proteins in hepatic retinoid processing under normal conditions and during chemical stress induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a chemical known to interfere with retinoid turnover and metabolism. Three separate studies were performed in wildtype control mice and transgenic mice that lack one or more isoforms of retinoic acid receptors (RAR), retinoid X receptors (RXR), or intracellular retinoid-binding proteins (CRABP I, CRABP II, CRBP I). Body and organ weight development was monitored from 2 weeks of age to adult, and hepatic levels of retinyl esters, retinol, and retinoic acid were investigated. In addition, hepatic concentrations of 9-cis-4-oxo-13,14-dihydro-retinoic acid, a recently discovered retinoid metabolite that has proven sensitive to both TCDD exposure and Vitamin A status, were also determined. Mice absent in the three proteins CRBP I, CRABP I, and CRABP II (CI/CAI/CAII-/-) displayed significantly lower hepatic retinyl ester, retinol, and all-trans-retinoic acid levels compared to wildtype mice, whereas the liver concentrations of 9-cis-4-oxo-13,14-dihydro-retinoic acid was considerably higher. After treatment with TCDD, hepatic total retinoids were almost entirely depleted in the CI/CAI/CAII-/- mice, whereas wildtype mice and mice lacking CRABP I, and CRABP II (CAI/CAII-/-) retained approximately 60-70% of their Vitamin A content compared to controls at 28 days. RAR and RXR knockout mice responded similarly to wildtype mice with respect to TCDD-induced retinoid disruption, with the exception of RXRbeta-/- mice which showed no decrease in hepatic Vitamin A concentration, suggesting that the role of RXRbeta in TCDD-induced retinoid disruption should be further investigated. Overall, the abnormal retinoid profile in the triple knockout mice (CI/CAI/CAII-/-), but not double knockout (CAI/CAII-/-) mice, suggests that a loss of CRBP I may account for the difference in retinoid profile in CI/CAI/CAII-/- mice, and is likely to result in an increased susceptibility to hepatic retinoid depletion following dioxin exposure.
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Affiliation(s)
- Pi Hoegberg
- Karolinska Institutet, Institute of Environmental Medicine, S-17177 Stockholm, Sweden
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208
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Donato LJ, Noy N. Suppression of mammary carcinoma growth by retinoic acid: proapoptotic genes are targets for retinoic acid receptor and cellular retinoic acid-binding protein II signaling. Cancer Res 2005; 65:8193-9. [PMID: 16166294 DOI: 10.1158/0008-5472.can-05-1177] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Retinoic acid (RA) displays pronounced anticarcinogenic activities in several types of cancer. Whereas the mechanisms that underlie this activity remain incompletely understood, tumor suppression by RA is believed to emanate primarily from its ability to regulate transcription of multiple target genes. Here, we investigated molecular events through which RA inhibits the growth of MCF-7 mammary carcinoma cells, focusing on the involvement of the two proteins that mediate transcriptional activation by RA, the nuclear hormone receptor retinoic acid receptor (RAR) and the cellular retinoic acid-binding protein (CRABP) II, in this process. RA treatment of MCF-7 cells did not affect cell cycle distribution but triggered pronounced apoptosis. Accordingly, expression array analyses revealed that RA induces the expression of several proapoptotic genes, including caspase 7 and caspase 9. Whereas caspase 7 is an indirect responder to RA signaling, caspase 9 is a novel direct target for RAR, and it harbors a functional retinoic acid response element in its second intron. In agreement with the known role of CRABP-II in enhancing the transcriptional activity of RAR, the binding protein augmented RA-induced up-regulation of caspase 9, cooperated with RA in activating both caspase 7 and 9, and amplified the ability of RA to trigger apoptosis. Surprisingly, the data indicate that CRABP-II also displays proapoptotic activities on its own. Specifically, overexpression of CRABP-II, in the absence of RA, up-regulated the expression of Apaf1 and triggered caspase 7 and caspase 9 cleavage. These observations suggest that, in addition to its known role in direct delivery of RA to RAR, CRABP-II may have an additional, RA-independent, function.
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Affiliation(s)
- Leslie J Donato
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA
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209
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Liu RZ, Sharma MK, Sun Q, Thisse C, Thisse B, Denovan-Wright EM, Wright JM. Retention of the duplicated cellular retinoic acid-binding protein 1 genes (crabp1a and crabp1b) in the zebrafish genome by subfunctionalization of tissue-specific expression. FEBS J 2005; 272:3561-71. [PMID: 16008556 DOI: 10.1111/j.1742-4658.2005.04775.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The cellular retinoic acid-binding protein type I (CRABPI) is encoded by a single gene in mammals. We have characterized two crabp1 genes in zebrafish, designated crabp1a and crabp1b. These two crabp1 genes share the same gene structure as the mammalian CRABP1 genes and encode proteins that show the highest amino acid sequence identity to mammalian CRABPIs. The zebrafish crabp1a and crabp1b were assigned to linkage groups 25 and 7, respectively. Both linkage groups show conserved syntenies to a segment of the human chromosome 15 harboring the CRABP1 locus. Phylogenetic analysis suggests that the zebrafish crabp1a and crabp1b are orthologs of the mammalian CRABP1 genes that likely arose from a teleost fish lineage-specific genome duplication. Embryonic whole mount in situ hybridization detected zebrafish crabp1b transcripts in the posterior hindbrain and spinal cord from early stages of embryogenesis. crabp1a mRNA was detected in the forebrain and midbrain at later developmental stages. In adult zebrafish, crabp1a mRNA was localized to the optic tectum, whereas crabp1b mRNA was detected in several tissues by RT-PCR but not by tissue section in situ hybridization. The differential and complementary expression patterns of the zebrafish crabp1a and crabp1b genes imply that subfunctionalization may be the mechanism for the retention of both crabp1 duplicated genes in the zebrafish genome.
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Affiliation(s)
- Rong-Zong Liu
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
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210
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Lefebvre P, Martin PJ, Flajollet S, Dedieu S, Billaut X, Lefebvre B. Transcriptional activities of retinoic acid receptors. VITAMINS AND HORMONES 2005; 70:199-264. [PMID: 15727806 DOI: 10.1016/s0083-6729(05)70007-8] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Vitamin A derivatives plays a crucial role in embryonic development, as demonstrated by the teratogenic effect of either an excess or a deficiency in vitamin A. Retinoid effects extend however beyond embryonic development, and tissue homeostasis, lipid metabolism, cellular differentiation and proliferation are in part controlled through the retinoid signaling pathway. Retinoids are also therapeutically effective in the treatment of skin diseases (acne, psoriasis and photoaging) and of some cancers. Most of these effects are the consequences of retinoic acid receptors activation, which triggers transcriptional events leading either to transcriptional activation or repression of retinoid-controlled genes. Synthetic molecules are able to mimic part of the biological effects of the natural retinoic acid receptors, all-trans retinoic acid. Therefore, retinoic acid receptors are considered as highly valuable therapeutic targets and limiting unwanted secondary effects due to retinoid treatment requires a molecular knowledge of retinoic acid receptors biology. In this review, we will examine experimental evidence which provide a molecular basis for the pleiotropic effects of retinoids, and emphasize the crucial roles of coregulators of retinoic acid receptors, providing a conceptual framework to identify novel therapeutic targets.
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Affiliation(s)
- Philippe Lefebvre
- INSERM U459 and Ligue Nationale Contre le Cancer, Faculté de Médecine de Lille, 59045 Lille cedex, France
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211
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Xiao H, Kaltashov IA. Transient structural disorder as a facilitator of protein-ligand binding: native H/D exchange-mass spectrometry study of cellular retinoic acid binding protein I. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2005; 16:869-79. [PMID: 15907702 DOI: 10.1016/j.jasms.2005.02.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2004] [Revised: 02/14/2005] [Accepted: 02/17/2005] [Indexed: 05/02/2023]
Abstract
Binding of all-trans Retinoic Acid (RA) to Cellular Retinoic Acid Binding Protein I (CRABP I) does not result in significant changes of the protein tertiary structure, even though the binding site is inaccessible in a static apo-protein conformation. One of the proposed scenarios for the protein-ligand binding process invokes the notion of a flexible portal region adjacent to the binding site, while another model suggests that the requisite dynamic events are induced by dimerization of the apo-protein in solution. In this work, RA binding to CRABP I is studied in dilute solutions (low micro-molar range), where no dimer and/or oligomer formation occurs. Modulation of backbone dynamics within various segments of the protein by its ligand is assessed using a combination of hydrogen exchange, electrospray ionization mass spectrometry, and collision-induced dissociation of protein ions in the gas phase. Consistent with the portal model of ligand entry, several protein segments (most of them containing residues making hydrophobic contacts to RA in the holo-form of the protein) are flexible in the absence of the ligand. At the same time, the two segments containing arginine residues forming a salt bridge with RA form the least flexible region in the apo-form of the protein. Although the presence of RA in solution reduces flexibility of all protein segments, the largest effect is observed within four strands that form one of the two beta-sheets enveloping a cavity which houses the ligand-binding site. These results are consistent with a model in which ligand binding occurs through a partially unstructured state of the protein with unobstructed access to the ligand-binding site. This intermediate (whose core is formed by the two stable arginine-containing strands) corresponds to a relatively low-energy local minimum on the apo-protein energy surface and is frequently sampled under native conditions.
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Affiliation(s)
- Hui Xiao
- Department of Chemistry, University of Massachusetts at Amherst, 710 North Pleasant Street, Amherst, MA 01003, USA
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212
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Armstrong JL, Redfern CPF, Veal GJ. 13-cis retinoic acid and isomerisation in paediatric oncology--is changing shape the key to success? Biochem Pharmacol 2005; 69:1299-306. [PMID: 15826600 DOI: 10.1016/j.bcp.2005.02.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Accepted: 02/08/2005] [Indexed: 11/18/2022]
Abstract
Retinoic acid isomers have been used with some success as chemotherapeutic agents, most recently with 13-cis retinoic acid showing impressive clinical efficacy in the paediatric malignancy neuroblastoma. The aim of this commentary is to review the evidence that 13-cis retinoic acid is a pro-drug, and consider the implications of retinoid metabolism and isomerisation for the further development of retinoic acid for cancer therapy. The low binding affinity of 13-cis retinoic acid for retinoic acid receptors, low activity in gene expression assays and the accumulation of the all-trans isomer in cells treated with 13-cis retinoic acid, coupled with the more-favourable pharmacokinetic profile of 13-cis retinoic acid compared to other isomers, suggest that intracellular isomerisation to all-trans retinoic acid is the key process underlying the biological activity of 13-cis retinoic acid. Intracellular metabolism of all-trans retinoic acid by a positive auto-regulatory loop may result in clinical resistance to retinoic acid. Agents that block or reduce the metabolism of all-trans retinoic acid are therefore attractive targets for drug development. Devising strategies to deliver 13-cis retinoic acid to tumour cells and facilitate the intracellular isomerisation of 13-cis retinoic acid, while limiting metabolism of all-trans retinoic acid, may have a major impact on the efficacy of 13-cis retinoic acid in paediatric oncology.
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Affiliation(s)
- Jane L Armstrong
- Northern Institute for Cancer Research, Paul O'Gorman Building, Medical School, Framlington Place, University of Newcastle Upon Tyne, Newcastle Upon Tyne NE2 4HH, UK.
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213
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Chung SSW, Wolgemuth DJ. Role of retinoid signaling in the regulation of spermatogenesis. Cytogenet Genome Res 2005; 105:189-202. [PMID: 15237207 PMCID: PMC3803148 DOI: 10.1159/000078189] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2003] [Accepted: 12/22/2003] [Indexed: 01/15/2023] Open
Abstract
While the need for vitamin A for the normal progression of male germ cell differentiation has been known for many years, the molecular mechanisms underlying this requirement are poorly understood. This review will explore the aspects of the effects on spermatogenesis of dietary deprivation of vitamin A, in particular as to how they compare to the male sterility that results from the genetic ablation of function of the retinoid receptor RARalpha. The effects of other genes involved with retinoid synthesis, transport, and degradation are also considered. The possible cellular mechanisms that may be affected by the lack of retinoid signaling are discussed, in particular, cell cycle regulation and cell-cell interaction, both of which are critical for normal spermatogenesis.
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Affiliation(s)
- S S W Chung
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
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214
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Sessler RJ, Noy N. A Ligand-Activated Nuclear Localization Signal in Cellular Retinoic Acid Binding Protein-II. Mol Cell 2005; 18:343-53. [PMID: 15866176 DOI: 10.1016/j.molcel.2005.03.026] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2004] [Revised: 12/28/2004] [Accepted: 03/31/2005] [Indexed: 12/30/2022]
Abstract
Primary sequences of proteins often contain motifs that serve as "signatures" for subcellular targeting, such as a nuclear localization signal (NLS). However, many nuclear proteins do not harbor a recognizable NLS, and the pathways that mediate their nuclear translocation are unknown. This work focuses on CRABP-II, a cytosolic protein that moves to the nucleus upon binding of retinoic acid. While CRABP-II does not contain an NLS in its primary sequence, such a motif could be recognized in the protein's tertiary structure. We map the retinoic acid-induced structural rearrangements that result in the presence of this NLS in holo- but not apo-CRABP-II. The signal, whose three-dimensional configuration aligns strikingly well with a "classical" NLS, mediates ligand-induced association of CRABP-II with importin alpha and is critical for nuclear localization of the protein. The ligand-controlled NLS "switch" of CRABP-II may represent a general mechanism for posttranslational regulation of the subcellular distribution of a protein.
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Affiliation(s)
- Richard J Sessler
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA
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215
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Armstrong JL, Ruiz M, Boddy AV, Redfern CPF, Pearson ADJ, Veal GJ. Increasing the intracellular availability of all-trans retinoic acid in neuroblastoma cells. Br J Cancer 2005; 92:696-704. [PMID: 15714209 PMCID: PMC2361877 DOI: 10.1038/sj.bjc.6602398] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Recent data indicate that isomerisation to all-trans retinoic acid (ATRA) is the key mechanism underlying the favourable clinical properties of 13-cis retinoic acid (13cisRA) in the treatment of neuroblastoma. Retinoic acid (RA) metabolism is thought to contribute to resistance, and strategies to modulate this may increase the clinical efficacy of 13cisRA. The aim of this study was to test the hypothesis that retinoids, such as acitretin, which bind preferentially to cellular retinoic acid binding proteins (CRABPs), or specific inhibitors of the RA hydroxylase CYP26, such as R116010, can increase the intracellular availability of ATRA. Incubation of SH-SY5Y cells with acitretin (50 μM) or R116010 (1 or 10 μM) in combination with either 10 μM ATRA or 13cisRA induced a selective increase in intracellular levels of ATRA, while 13cisRA levels were unaffected. CRABP was induced in SH-SY5Y cells in response to RA. In contrast, acitretin had no significant effect on intracellular retinoid concentrations in those neuroblastoma cell lines that showed little or no induction of CRABP after RA treatment. Both ATRA and 13cisRA dramatically induced the expression of CYP26A1 in SH-SY5Y cells, and treatment with R116010, but not acitretin, potentiated the RA-induced expression of a reporter gene and CYP26A1. The response of neuroblastoma cells to R116010 was consistent with inhibition of CYP26, indicating that inhibition of RA metabolism may further optimise retinoid treatment in neuroblastoma.
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Affiliation(s)
- J L Armstrong
- Northern Institute for Cancer Research, Paul O'Gorman Building, Medical School, Framlington Place, University of Newcastle Upon Tyne, Newcastle Upon Tyne NE2 4HH, UK.
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216
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Schachtrup C, Emmler T, Bleck B, Sandqvist A, Spener F. Functional analysis of peroxisome-proliferator-responsive element motifs in genes of fatty acid-binding proteins. Biochem J 2005; 382:239-45. [PMID: 15130092 PMCID: PMC1133936 DOI: 10.1042/bj20031340] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2003] [Revised: 04/13/2004] [Accepted: 05/07/2004] [Indexed: 11/17/2022]
Abstract
Retinoic acids and long-chain fatty acids are lipophilic agonists of nuclear receptors such as RXRs (retinoic X receptors) and PPARs (peroxisome-proliferator-activated receptors) respectively. These agonists are also ligands of intracellular lipid-binding proteins, which include FABPs (fatty acid-binding proteins). We reported previously that L (liver-type)-FABP targets fatty acids to the nucleus of hepatocytes and affects PPARalpha activation, which binds together with an RXR subtype to a PPRE (peroxisome-proliferator-responsive element). In the present study, we first determined the optimal combination of murine PPAR/RXR subtypes for binding to known murine FABP-PPREs and to those found by computer search and then tested their in vitro functionality. We show that all PPARs bind to L-FABP-PPRE, PPARalpha, PPARgamma1 and PPARgamma2 to A (adipocyte-type)-FABP-PPRE. All PPAR/RXR heterodimers transactivate L-FABP-PPRE, best are combinations of PPARalpha with RXRalpha or RXRgamma. In contrast, PPARalpha heterodimers do not transactivate A-FABP-PPRE, best combinations are of PPARgamma1 with RXRalpha and RXRgamma, and of PPARgamma2 with all RXR subtypes. We found that the predicted E (epidermal-type)- and H (heart-type)-FABP-PPREs are not activated by any PPAR/RXR combination without or with the PPAR pan-agonist bezafibrate. In the same way, C2C12 myoblasts transfected with promoter fragments of E-FABP and H-FABP genes containing putative PPREs are also not activated through stimulation of PPARs with bezafibrate applied to the cells. These results demonstrate that only PPREs of L- and A-FABP promoters are functional, and that binding of PPAR/RXR heterodimers to a PPRE in vitro does not necessarily predict transactivation.
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Affiliation(s)
- Christian Schachtrup
- *Department of Biochemistry, University of Münster, Wilhelm-Klemm-Str. 2, 48149 Münster, Germany
| | - Tanja Emmler
- *Department of Biochemistry, University of Münster, Wilhelm-Klemm-Str. 2, 48149 Münster, Germany
| | - Bertram Bleck
- *Department of Biochemistry, University of Münster, Wilhelm-Klemm-Str. 2, 48149 Münster, Germany
| | - Anton Sandqvist
- †Department of Biochemistry and Pharmacy, Åbo Akademi University, PO Box 66, FIN-20521, Turku, Finland
| | - Friedrich Spener
- *Department of Biochemistry, University of Münster, Wilhelm-Klemm-Str. 2, 48149 Münster, Germany
- To whom correspondence should be addressed (email )
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217
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Lane MA, Bailey SJ. Role of retinoid signalling in the adult brain. Prog Neurobiol 2005; 75:275-93. [PMID: 15882777 DOI: 10.1016/j.pneurobio.2005.03.002] [Citation(s) in RCA: 281] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2004] [Revised: 03/11/2005] [Accepted: 03/14/2005] [Indexed: 11/30/2022]
Abstract
Vitamin A (all-trans-retinol) is the parent compound of a family of natural and synthetic compounds, the retinoids. Retinoids regulate gene transcription in numerous cells and tissues by binding to nuclear retinoid receptor proteins, which act as transcription factors. Much of the research conducted on retinoid signalling in the nervous system has focussed on developmental effects in the embryonic or early postnatal brain. Here, we review the increasing body of evidence indicating that retinoid signalling plays an important role in the function of the mature brain. Components of the metabolic pathway for retinoids have been identified in adult brain tissues, suggesting that all-trans-retinoic acid (ATRA) can be synthesized in discrete regions of the brain. The distribution of retinoid receptor proteins in the adult nervous system is different from that seen during development; and suggests that retinoid signalling is likely to have a physiological role in adult cortex, amygdala, hypothalamus, hippocampus, striatum and associated brain regions. A number of neuronal specific genes contain recognition sequences for the retinoid receptor proteins and can be directly regulated by retinoids. Disruption of retinoid signalling pathways in rodent models indicates their involvement in regulating synaptic plasticity and associated learning and memory behaviours. Retinoid signalling pathways have also been implicated in the pathophysiology of Alzheimer's disease, schizophrenia and depression. Overall, the data underscore the likely importance of adequate nutritional Vitamin A status for adult brain function and highlight retinoid signalling pathways as potential novel therapeutic targets for neurological diseases.
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Affiliation(s)
- Michelle A Lane
- Department of Human Ecology, Division of Nutritional Sciences, The University of Texas at Austin, Austin, TX 78712, USA.
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218
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Arslan AA, Gold LI, Mittal K, Suen TC, Belitskaya-Levy I, Tang MS, Toniolo P. Gene expression studies provide clues to the pathogenesis of uterine leiomyoma: new evidence and a systematic review. Hum Reprod 2005; 20:852-63. [PMID: 15705628 DOI: 10.1093/humrep/deh698] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Uterine leiomyomas are extremely common and a major cause of pelvic pain, bleeding, infertility, and the leading indication for hysterectomy. Familial and epidemiological studies provide compelling evidence that genetic alterations play an important role in leiomyoma development. METHODS Using Affymetrix U133A GeneChip we analysed expression profiles of 22,283 genes in paired samples of leiomyoma and adjacent normal myometrium. We compared our results with previously published data on gene expression in uterine leiomyoma and identified the overlapping gene alterations. RESULTS We detected 80 genes with average differences of > or = 2-fold and false discovery rates of < 5% (14 overexpressed and 66 underexpressed). A comparative analysis including eight previous gene expression studies revealed eight prominent genes (ADH1, ATF3, CRABP2, CYR61, DPT, GRIA2, IGF2, MEST) identified by at least five different studies, eleven genes (ALDH1, CD24, CTGF, DCX, DUSP1, FOS, GAGEC1, IGFBP6, PTGDS, PTGER3, TYMS) reported by four studies, twelve genes (ABCA, ANXA1, APM2, CCL21, CDKN1A, CRMP1, EMP1, ESR1, FY, MAP3K5, TGFBR2, TIMP3) identified by three studies, and 40 genes reported by two different studies. CONCLUSIONS Review of gene expression data revealed concordant changes in genes regulating retinoid synthesis, IGF metabolism, TGF-beta signaling and extracellular matrix formation. Gene expression studies provide clues to the relevant pathways of leiomyoma development.
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Affiliation(s)
- Alan A Arslan
- Department of Obstetrics & Gynecology, Department of Environmental Medicine, Department of Pathology and Department of Medicine, New York University School of Medicine, New York, NY 10016, USA.
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219
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Li XH, Kakkad B, Ong DE. Estrogen directly induces expression of retinoic acid biosynthetic enzymes, compartmentalized between the epithelium and underlying stromal cells in rat uterus. Endocrinology 2004; 145:4756-62. [PMID: 15205379 DOI: 10.1210/en.2004-0514] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Estrogen (E2) has been shown to induce the biosynthesis of retinoic acid (RA) in rat uterus. Here we examined whether E2 could directly induce the enzymes involved in this process by using the ovariectomized rat. A retinol dehydrogenase that we have previously described, eRolDH, and the retinal dehydrogenase, RalDH II, were found to have markedly increased uterine mRNA levels within 4 h of E2 administration, independent of the prior administration of puromycin. eRolDH and RalDH II and their mRNAs were also increased in uteri of rats during estrus. This indicated that RA biosynthesis in rat uterus is directly controlled by E2 and provides a direct link between the action of a steroid hormone and retinoid action. We also examined the cell-specific localization of RalDH II by immunohistochemistry. The enzyme was observed in the stromal compartment, particularly in cells close to the uterine lumenal epithelium. eRolDH was observed only in the lining epithelial cells. Taken together with the previous observations of cellular retinol-binding protein and cellular retinoic acid-binding protein, type two also being expressed in the lumenal epithelium, we propose that RA production is compartmentalized, with retinol oxidation occurring in the lumenal epithelium and subsequent oxidation of retinal to RA occurring in the underlying stromal cells.
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Affiliation(s)
- Xiao-Hong Li
- Department of Biochemistry, Vanderbilt University, 23rd Avenue at Pierce, Nashville, Tennessee 37232, USA
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220
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Maden M, Hind M. Retinoic acid in alveolar development, maintenance and regeneration. Philos Trans R Soc Lond B Biol Sci 2004; 359:799-808. [PMID: 15293808 PMCID: PMC1693372 DOI: 10.1098/rstb.2004.1470] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Recent data suggest that exogenous retinoic acid (RA), the biologically active derivative of vitamin A, can induce alveolar regeneration in a rat model of experimental emphysema. Here, we describe a mouse model of disrupted alveolar development using dexamethasone administered postnatally. We show that the effects of dexamethasone are concentration dependent, dose dependent, long lasting and result in a severe loss of alveolar surface area. When RA is administered to these animals as adults, lung architecture and the surface area per unit of body weight are completely restored to normal. This remarkable effect may be because RA is required during normal alveolar development and administering RA re-awakens gene cascades used during development. We provide evidence that RA is required during alveologenesis in the mouse by showing that the levels of the retinoid binding proteins, the RA receptors and two RA synthesizing enzymes peak postnatally. Furthermore, an inhibitor of RA synthesis, disulphiram, disrupts alveologenesis. We also show that RA is required throughout life for the maintenance of lung alveoli because when rats are deprived of dietary retinol they lose alveoli and show the features of emphysema. Alveolar regeneration with RA may therefore be an important novel therapeutic approach to the treatment of respiratory diseases characterized by a reduced gas-exchanging surface area such as bronchopulmonary dysplasia and emphysema for which there are currently no treatments.
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Affiliation(s)
- Malcolm Maden
- MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK.
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221
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Jackman WR, Mougey JM, Panopoulou GD, Kimmel CB. crabp and maf highlight the novelty of the amphioxus club-shaped gland. ACTA ZOOL-STOCKHOLM 2004. [DOI: 10.1111/j.0001-7272.2004.00161.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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222
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Janes SM, Ofstad TA, Campbell DH, Watt FM, Prowse DM. Transient activation of FOXN1 in keratinocytes induces a transcriptional programme that promotes terminal differentiation: contrasting roles of FOXN1 and Akt. J Cell Sci 2004; 117:4157-68. [PMID: 15316080 DOI: 10.1242/jcs.01302] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The forkhead transcription factor FOXN1 is required for normal cutaneous and thymic epithelial development. Mutations in FOXN1 give rise to the nude phenotype in mice, rats and man. However, the genes that are regulated by FOXN1 are unknown. To investigate FOXN1 function we expressed an inducible form of the protein, FOXN1ER, that is activated by 4-hydroxytamoxifen in primary human epidermal keratinocytes. Transient activation of FOXN1 decreased the proportion of keratinocytes that formed actively growing clones attributable to stem cell founders and increased the number of abortive clones, without inducing apoptosis. Within 24 hours the majority of cells had initiated terminal differentiation, as assessed by involucrin expression. We performed a cDNA microarray experiment to analyse changes in the transcription of approximately 6000 genes. Following FOXN1 activation we detected increases of two fold or greater in the RNA levels of over 30 genes. Genes promoting growth arrest, survival and differentiation featured prominently and markers of early events in keratinocyte differentiation were also detected. Since one of the induced genes was Akt we investigated whether Akt played a role in terminal differentiation. Activation of PI 3-kinase but not Akt was necessary for FOXN1-induced differentiation. In reconstituted epidermis FOXN1 promoted early stages of terminal differentiation whereas Akt activation was sufficient to induce late stages, including formation of the cornified layers. These results establish a role for FOXN1 in initiation of terminal differentiation and implicate Akt in subsequent events.
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Affiliation(s)
- Sam M Janes
- Keratinocyte Laboratory, Cancer Research UK, London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3PX, UK
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223
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Won JY, Nam EC, Yoo SJ, Kwon HJ, Um SJ, Han HS, Kim SH, Byun Y, Kim SY. The effect of cellular retinoic acid binding protein-I expression on the CYP26-mediated catabolism of all-trans retinoic acid and cell proliferation in head and neck squamous cell carcinoma. Metabolism 2004; 53:1007-12. [PMID: 15281009 DOI: 10.1016/j.metabol.2003.12.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The aim of this study was to confirm if catabolism of all-trans retinoic acid (RA) is enhanced by type I cellular retinoic acid binding protein (CRABP-I) expression and to investigate the effect of this enhanced catabolism on cell proliferation of the head and neck squamous cell carcinoma (HNSCC) cell line, AMC-HN-7. We also analyzed the effects of CRABP-I on RA-induced retinoic acid receptor (RAR) activity. The expression of the CRABP-I in stably transfected AMC-HN-7 cell lines (HN7-BPIa and HN7-BPIb) resulted in a lower sensitivity to administered RA compared with that of controls in a clonogenic assay. HN7-BPIs cells showed an increased amount of polar metabolites of RA in thin-layer chromatography. The transcriptional activity of the reporter plasmid RARE(DR5)-tk-CAT after the treatment of RA was lesser in HN7-BPIs than in controls. These results suggest that the increased CYP26-mediated catabolism of RA by CRABP-I transfection might decrease the amount of RA that is accessible to the nuclear receptors and make HNSCC cells resistant to RA.
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Affiliation(s)
- Jun Yeon Won
- Department of Otolaryngology, University of Kangwon College of Medicine, Chunchon, South Korea
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224
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Yamashita S, Nomoto T, Ohta T, Ohki M, Sugimura T, Ushijima T. Differential expression of genes related to levels of mucosal cell proliferation among multiple rat strains by using oligonucleotide microarrays. Mamm Genome 2004; 14:845-52. [PMID: 14724737 DOI: 10.1007/s00335-003-2299-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2003] [Accepted: 07/18/2003] [Indexed: 10/26/2022]
Abstract
Induction levels of cell proliferation, in response to gastric mucosal damage by N-methyl- N'-nitro- N-nitrosoguanidine (MNNG), are different among rat strains and correlate with susceptibility to MNNG-induced gastric carcinogenesis. Here, we used oligonucleotide microarrays to search for genes that show expression levels accordant with the extents of cell proliferation among six rat strains. Expression levels of 8,800 probe sets were analyzed in the pylorus of ACI, LEW, WKY (strains with strong cell proliferation), F344, (ACI x BUF)F1, and BUF rats (strains with weak cell proliferation) after 2-week MNNG treatment. No genes showed complete accordance, and 22 genes showed accordance with one or two exceptions. After confirmation by quantitative RT-PCR, four genes--cellular retinoic acid-binding protein II ( Crabp2), fatty acid binding protein 1 ( Fabp1), progastricsin (pepsinogen C, Pgc), and UDP-glucuronosyltransferase 2 family member 5 ( Ugt2b5)--were found to show good accordance with only one exception. Crabp2, Fabp1, and Ugt2b5 were differentially expressed between ACI and BUF rats both before and after MNNG treatment. Although Crabp2 had been identified as one of the 16 genes differentially expressed between ACI and BUF rats with cDNA-RDA, Fabp1 and Ugt2b5 were newly identified in this study. All three genes are known to be involved in retinoic acid-mediated signaling and could be involved in the control of differential induction of cell proliferation.
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Affiliation(s)
- Satoshi Yamashita
- Carcinogenesis Division, National Cancer Center Research Institute, 1-1 Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045, Japan
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225
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Lee SJ, Jeon HB, Lee JH, Yoo JS, Chun JS, Yoo YJ. Identification of proteins differentially expressed during chondrogenesis of mesenchymal cells. FEBS Lett 2004; 563:35-40. [PMID: 15063719 DOI: 10.1016/s0014-5793(04)00243-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2004] [Revised: 02/19/2004] [Accepted: 02/25/2004] [Indexed: 10/26/2022]
Abstract
We performed comparative proteome analysis of mesenchymal cells and chondrocytes to identify proteins differentially expressed during chondrogenesis. Nine such proteins were identified. Type II collagen, matrilin-1, carbonic anhydrase-II (CA-II), 3'-phosphoadenosine 5'-phosphosulfate (PAPS) synthetase-2, and aldo-keto reductase were increased during chondrogenesis, whereas cellular retinoic acid binding protein-I (CRABP-I), CRABP-II, cytoplasmic type 5 actin, and fatty acid binding protein were decreased or almost disappeared. Expression of type II collagen, matrilin-1, PAPS synthetase-2, and CA-II was regulated by extracellular signal-regulated protein kinase, protein kinase C, and p38 kinase, signaling molecules known to regulate chondrogenesis.
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Affiliation(s)
- Sun Joo Lee
- Department of Life Science, Kwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712, South Korea
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226
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Kim SK, Yoo JI, Cho BK, Hong SJ, Kim YK, Moon JA, Kim JH, Chung YN, Wang KC. Elevation of CRABP-I in the cerebrospinal fluid of patients with Moyamoya disease. Stroke 2003; 34:2835-41. [PMID: 14605320 DOI: 10.1161/01.str.0000100159.43123.d7] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The etiology of moyamoya disease (MMD) remains obscure. This study was undertaken to identify specific proteins associated with the pathogenesis of MMD. METHODS We studied cerebrospinal fluid (CSF) from 20 patients with angiographically confirmed MMD (4 boys and 16 girls; age range, 3 to 13 years; mean, 7.5 years) and 4 control patients with cerebral palsy who underwent selective dorsal rhizotomy (2 boys and 2 girls; age range, 5 to 10 years; mean, 7.3 years). CSF proteins were analyzed by 2-dimensional polyacrylamide gel electrophoresis, and protein identification was performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The presence of specific CSF protein in patients with MMD was confirmed by Western blotting. In addition, cerebral CSF was also tested in 7 patients who had other brain diseases but no MMD (2 boys and 5 girls; age range, 1 to 12 years; mean, 6.9 years). RESULTS We identified 1 polypeptide spot (Mr of 13 to 15 kDa and isoelectric point of 5 to 5.5) that was differentially expressed in the CSF samples of MMD patients (mean optical density intensity, 0.36+/-0.24; range, 0.05 to 0.92) and control spinal CSF samples (mean, 0.03+/-0.04; range, 0 to 0.08; P=0.002). This polypeptide was identified as cellular retinoic acid-binding protein (CRABP)-I. High levels of expression of CRABP-I in the CSF from 17 MMD children were confirmed by Western blotting. CONCLUSIONS The analysis of the CSF of MMD patients reveals high CRABP-I expression. The present study suggests that the elevation of CRABP-I in CSF may be a candidate for pathogenesis of MMD.
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Affiliation(s)
- Seung-Ki Kim
- Division of Pediatric Neurosurgery and Laboratory for Fetal Medicine Research in Clinical Research Institute, Seoul National University Hospital, and Neuroscience Research Institute, Seoul National University Medical Research Center, Korea
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227
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Shaw N, Elholm M, Noy N. Retinoic acid is a high affinity selective ligand for the peroxisome proliferator-activated receptor beta/delta. J Biol Chem 2003; 278:41589-92. [PMID: 12963727 DOI: 10.1074/jbc.c300368200] [Citation(s) in RCA: 189] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Retinoic acid (RA) modulates transcription of numerous target genes, thereby regulating a myriad of biological processes. It is well established that RA functions by activating retinoic acid receptors (RARs), which, in turn, control cell differentiation, proliferation, and apoptosis. However, perplexing reports of diverse and sometime opposing actions of RA have been published. Hence, while RA induces apoptosis and inhibits cell growth in some settings, it potentiates proliferation and acts as an anti-apoptotic agent in others. These observations raise the possibility that signaling pathways other than RAR may be involved in mediating RA activities. Here we show that RA is a high affinity ligand for another nuclear receptor, namely the orphan receptor peroxisome proliferator-activated receptor (PPAR) beta/delta. We demonstrate that while RA does not activate PPARalpha and PPARgamma, it binds to PPARbeta/delta with nanomolar affinity, modulates the conformation of the receptor, promotes interaction with the coactivator SRC-1, and efficiently activates PPARbeta/delta-mediated transcription. Transcriptional signaling by RA is thus exerted by a dual pathway, providing a rationale for understanding divergent cellular responses to this hormone.
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Affiliation(s)
- Natacha Shaw
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
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228
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Li XH, Ong DE. Cellular retinoic acid-binding protein II gene expression is directly induced by estrogen, but not retinoic acid, in rat uterus. J Biol Chem 2003; 278:35819-25. [PMID: 12842898 DOI: 10.1074/jbc.m302551200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
It has been suggested that cellular retinoic acid-binding protein (II) (CRABP(II)) may have a role in the movement of retinoic acid (RA) to its nuclear receptors, thereby enhancing the action of RA in the cells in which it is expressed. RA has also been shown to increase expression of CRABP(II). Previous work from our laboratory has shown that 17 beta-estradiol (E2) administration to prepubertal female rats leads to acquisition of the ability of the lining epithelium to synthesize RA as well as to express CRABP(II). To determine whether this appearance of CRABP(II) was dependent on the production of RA, both E2 and RA were administered to ovariectomized rats. E2 administration induced expression of the CRABP(II) gene in the uterus within 4 h, and this induction was not inhibited by prior administration of puromycin, indicating that the induction was direct. In contrast, RA caused no change in CRABP(II) message level, even at times as late as 48 h after administration. Isolation and analysis of 4.5 kb of the 5'-flanking region of the gene revealed no apparent E2-response element. Using this portion of the gene to drive expression of the luciferase gene in transfected cells allowed identification of a region containing an imperfect estrogen-response element and estrogen-response element half-site, necessary for E2-driven induction. A possible Sp1 binding site in the 5'-flanking region of the CRABP(II) gene was also required for this induction. The ability of E2 to induce expression of CRABP(II) suggests that it can enhance the activity of RA, directly affecting expression of retinoid-responsive genes.
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Affiliation(s)
- Xiao-Hong Li
- Department of Biochemistry, School of Medicine, Vanderbilt University, Nashville, Tennessee 37232, USA
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229
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Abstract
Retinoids regulate gene transcription by binding to the nuclear receptors, the retinoic acid (RA) receptors (RARs), and the retinoid X receptors (RXRs). RARs and RXRs are ligand-activated transcription factors for the regulation of RA-responsive genes. The actions of RARs and RXRs on gene transcription require a highly coordinated interaction with a large number of coactivators and corepressors. This review focuses on our current understanding of these coregulators known to act in concert with RARs and RXRs. The mechanisms of action of these coregulators are beginning to be uncovered and include the modification of chromatin and the recruitment of basal transcription factors. Challenges remain to understand the specificity of action of RARs and RXRs and the formation of specific transcription complexes consisting of the receptors, coregulators, and other unknown factors.
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Affiliation(s)
- Li-Na Wei
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA.
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230
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Zhelyaznik N, Schrage K, McCaffery P, Mey J. Activation of retinoic acid signalling after sciatic nerve injury: up-regulation of cellular retinoid binding proteins. Eur J Neurosci 2003; 18:1033-40. [PMID: 12956703 DOI: 10.1046/j.1460-9568.2003.02834.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In mammalian peripheral nerves a crush lesion causes interactions between injured neurons, Schwann cells and haematogenous macrophages that can lead to successful axonal regeneration. We suggest that the transcriptional activator retinoic acid (RA), takes part in gene regulation after peripheral nerve injury and that RA signalling is activated via the cellular retinoic acid binding protein (CRABP)-II and cellular retinol binding protein (CRBP)-I. With RT-PCR and immunoblotting all necessary components of the RA signalling pathway were detected in the sciatic nerve of adult rats. These are retinoic acid receptors, retinoid X receptors, the retinoic acid synthesizing enzymes RALDH-1, RALDH-2, and RALDH-3, in addition, the cellular retinoid binding proteins CRBP-I, CRABP-I and CRABP-II. Enzyme activity of RALDH-2 was detectable in the nerve, and using a transgenic reporter mouse we found local activation of RA responsive elements in the regenerating nerve. Sciatic nerve crush as well as transection resulted in a more than 10-fold up-regulation of CRBP-I, which is thought to facilitate the synthesis of RA. Both kinds of injury also caused a 15-fold increase in transcript and protein concentration of CRABP-II, a possible mediator of RA transfer to its nuclear receptors.
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Affiliation(s)
- Nina Zhelyaznik
- Institut für Biologie II, RWTH Aachen, Kopernikusstr 16, 52074 Aachen, Germany
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231
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Golovleva I, Bhattacharya S, Wu Z, Shaw N, Yang Y, Andrabi K, West KA, Burstedt MSI, Forsman K, Holmgren G, Sandgren O, Noy N, Qin J, Crabb JW. Disease-causing mutations in the cellular retinaldehyde binding protein tighten and abolish ligand interactions. J Biol Chem 2003; 278:12397-402. [PMID: 12536144 DOI: 10.1074/jbc.m207300200] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutations in the human cellular retinaldehyde binding protein (CRALBP) gene cause retinal pathology. To understand the molecular basis of impaired CRALBP function, we have characterized human recombinant CRALBP containing the disease causing mutations R233W or M225K. Protein structures were verified by amino acid analysis and mass spectrometry, retinoid binding properties were evaluated by UV-visible and fluorescence spectroscopy and substrate carrier functions were assayed for recombinant 11-cis-retinol dehydrogenase (rRDH5). The M225K mutant was less soluble than the R233W mutant and lacked retinoid binding capability and substrate carrier function. In contrast, the R233W mutant exhibited solubility comparable to wild type rCRALBP and bound stoichiometric amounts of 11-cis- and 9-cis-retinal with at least 2-fold higher affinity than wild type rCRALBP. Holo-R233W significantly decreased the apparent affinity of rRDH5 for 11-cis-retinoid relative to wild type rCRALBP. Analyses by heteronuclear single quantum correlation NMR demonstrated that the R233W protein exhibits a different conformation than wild type rCRALBP, including a different retinoid-binding pocket conformation. The R233W mutant also undergoes less extensive structural changes upon photoisomerization of bound ligand, suggesting a more constrained structure than that of the wild type protein. Overall, the results show that the M225K mutation abolishes and the R233W mutation tightens retinoid binding and both impair CRALBP function in the visual cycle as an 11-cis-retinol acceptor and as a substrate carrier.
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Affiliation(s)
- Irina Golovleva
- Department of Medical Biosciences, Umeå University, S-901 85 Umeå, Sweden.
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232
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Chen AC, Yu K, Lane MA, Gudas LJ. Homozygous deletion of the CRABPI gene in AB1 embryonic stem cells results in increased CRABPII gene expression and decreased intracellular retinoic acid concentration. Arch Biochem Biophys 2003; 411:159-73. [PMID: 12623064 DOI: 10.1016/s0003-9861(02)00732-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The cellular retinoic acid (RA) binding proteins I and II (CRABPI and CRABPII), intracellular proteins which bind retinoic acid with high affinity, are involved in the actions of RA, though their exact roles are not fully understood. We have generated several genetically engineered AB1 cell lines in which both alleles of the CRABPI gene have been deleted by homologous recombination. We have used these CRABPI knockout cell lines to examine the consequences of functional loss of CRABPI on RA-induced gene expression and RA metabolism in the murine embryonic stem cell line, AB1, which undergoes differentiation in response to RA. Complete lack of CRABPI results in decreased intracellular [3H]RA concentrations under conditions in which external concentrations of [3H]RA are low (1-10nM) and in an altered distribution of [3H] polar metabolites of [3H]RA in the cell and in the medium. Fewer [3H] polar metabolites are retained within the CRABPI(-/-) cells compared to the wild-type cells. These data suggest that CRABPI functions to regulate the intracellular concentrations of retinoic acid and to maintain high levels of oxidized retinoic acid metabolites such as 4-oxoretinoic acid within cells.
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Affiliation(s)
- Anne C Chen
- Department of Pharmacology, Weill Medical College of Cornell University, New York, NY 10021, USA
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233
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Despouy G, Bastie JN, Deshaies S, Balitrand N, Mazharian A, Rochette-Egly C, Chomienne C, Delva L. Cyclin D3 is a cofactor of retinoic acid receptors, modulating their activity in the presence of cellular retinoic acid-binding protein II. J Biol Chem 2003; 278:6355-62. [PMID: 12482873 DOI: 10.1074/jbc.m210697200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Ligand-induced transcription activation of retinoic acid (RA) target genes by nuclear receptors (retinoic acid (RAR) and retinoid X (RXR) receptors) depends on the recruitment of coactivators. We have previously demonstrated that the small 15-kDa cellular RA-binding protein II (CRABPII) is a coactivator present in the RA-dependent nuclear complex. As identifying cell-specific partners of CRABPII might help to understand the novel control of RA signaling, we performed a yeast two-hybrid screen of a hematopoietic HL-60 cDNA library using human CRABPII as bait and have subsequently identified human cyclin D3 as a partner of CRABPII. Cyclin D3 interacted with CRABPII in a ligand-independent manner and equally bound RAR alpha, but not RXR alpha, and only in the presence of RA. We further show that cyclin D3 positively modulated RA-mediated transcription through CRABPII. Therefore, cyclin D3 may be part of a ternary complex with CRABPII and RAR. Finally, we show that cyclin D3 expression paralleled HL-60 differentiation and arrest of cell growth. These findings led us to speculate that control of cell proliferation during induction of differentiation may directly involve, at the transcriptional level, nuclear receptors, coactivators, and proteins of the cell cycle in a cell- and nuclear receptor-specific manner.
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Affiliation(s)
- Gilles Despouy
- Laboratoire de Biologie Cellulaire Hématopoiétique, Equipe Mixte Inserm 00-03, Institut Universitaire d'Hématologie, Hôpital Saint-Louis, 1 Avenue Claude Vellefaux, Paris 75010, USA
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234
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Recalde D, Zakin MM. Genetics and molecular biology. Curr Opin Lipidol 2003; 14:99-101. [PMID: 12544665 DOI: 10.1097/00041433-200302000-00014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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235
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Haunerland NH, Spener F. Properties and physiological significance of fatty acid binding proteins. LIPOBIOLOGY 2003. [DOI: 10.1016/s1569-2558(03)33007-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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236
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Samuel S, Bernstein LR. Adhesion, migration, transcriptional, interferon-inducible, and other signaling molecules newly implicated in cancer susceptibility and resistance of JB6 cells by cDNA microarray analyses. Mol Carcinog 2003; 39:34-60. [PMID: 14694446 DOI: 10.1002/mc.10163] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Relative expression levels of 9500 genes were determined by cDNA microarray analyses in mouse skin JB6 cells susceptible (P+) and resistant (P-) to 12-O-tetradecanoyl phorbol-13 acetate (TPA)-induced neoplastic transformation. Seventy-four genes in 6 functional classes were differentially expressed: (I) extracellular matrix (ECM) and basement membrane (BM) proteins (20 genes). P+ cells express higher levels than P- cells of several collagens and proteases, and lower levels of protease inhibitors. Multiple genes encoding adhesion molecules are expressed preferentially in P- cells, including six genes implicated in axon guidance and adhesion. (II) Cytoskeletal proteins (13 genes). These include actin isoforms and regulatory proteins, almost all preferentially expressed in P- cells. (III) Signal transduction proteins (12 genes). Among these are Ras-GTPase activating protein (Ras-GAP), the deleted in oral cancer-1 and SLIT2 tumor suppressors, and connexin 43 (Cx43) gap junctional protein, all expressed preferentially in P- cells. (IV) Interferon-inducible proteins (3 genes). These include interferon-inducible protein (IFI)-16, an Sp1 transcriptional regulator expressed preferentially in P- cells. (V) Other transcription factors (4 genes). Paired related homeobox gene 2 (Prx2)/S8 homeobox, and retinoic acid (RA)-regulated nur77 and cellular retinoic acid-binding protein II (CRABPII) transcription factors are expressed preferentially in P- cells. The RIN-ZF Sp-transcriptional suppressor exhibits preferential P+ expression. (VI) Genes of unknown functions (22 sequences). Numerous mesenchymal markers are expressed in both cell types. Data for multiple genes were confirmed by real-time PCR. Overall, 26 genes were newly implicated in cancer. Detailed analyses of the functions of the genes and their interrelationships provided converging evidence for their possible roles in implementing genetic programs mediating cancer susceptibility and resistance. These results, in conjunction with cell wounding and phalloidin staining data, indicated that concerted genetic programs were implemented that were conducive to cell adhesion and tumor suppression in P- cells and that favored matrix turnover, cell motility, and abrogation of tumor suppression in P+ cells. Such genetic programs may in part be orchestrated by Sp-, RA-, and Hox-transcriptional regulatory pathways implicated in this study.
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Affiliation(s)
- Shaija Samuel
- Department of Pathology and Laboratory Medicine, Texas A & M University System Health Science Center, College Station, Texas, USA
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237
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Abstract
Since the late 1980s, there has been an explosion of information on the molecular mechanisms and functions of vitamin A. This review focuses on the essential role of vitamin A in female reproduction and embryonic development and the metabolism of vitamin A (retinol) that results in these functions. Evidence strongly supports that in situ-generated all-trans retinoic acid (atRA) is the functional form of vitamin A in female reproduction and embryonic development. This is supported by the ability to reverse most reproductive and developmental blocks found in vitamin A deficiency with atRA, the block in embryonic development that occurs in retinaldehyde dehydrogenase type 2 null mutant mice, and the essential roles of the retinoic acid receptors, at least in embryogenesis. Early studies of embryos from marginally vitamin A-deficient (VAD) pregnant rats revealed a collection of defects called the vitamin A-deficiency syndrome. The manipulation of all-trans retinoic acid (atRA) levels in the diet of VAD female rats undergoing a reproduction cycle has proved to be an important new tool in deciphering the points of atRA function in early embryos and has provided a means to generate large numbers of embryos at later stages of development with the vitamin A-deficiency syndrome. The essentiality of the retinoid receptors in mediating the activity of atRA is exemplified by the many compound null mutant embryos that now recapitulate both the original vitamin A-deficiency syndrome and exhibit a host of new defects, many of which can also be observed in the VAD-atRA-supported rat embryo model and in retinaldehyde dehydrogenase type 2 (RALDH2) mutant mice. A major task for the future is to elucidate the atRA-dependent pathways that are normally operational in vitamin A-sufficient animals and that are perturbed in deficiency, thus leading to the characteristic VAD phenotypes described above.
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Affiliation(s)
- Margaret Clagett-Dame
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
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238
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Habeck M. Boost for retinoic acid cancer therapy. Drug Discov Today 2002; 7:1024-5. [PMID: 12546884 DOI: 10.1016/s1359-6446(02)02481-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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239
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Gallagher RE. Retinoic acid resistance in acute promyelocytic leukemia. Leukemia 2002; 16:1940-58. [PMID: 12357346 DOI: 10.1038/sj.leu.2402719] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2002] [Accepted: 06/21/2002] [Indexed: 01/01/2023]
Abstract
Primary resistance of PML-RARalpha-positive acute promyelocytic leukemia (APL) to the induction of clinical remission (CR) by all-trans retinoic acid (ATRA) is rare but markedly increases in frequency after > or =2 relapses from chemotherapy-induced CRs. Nevertheless, even in de novo cases, the primary response of ATRA-naive cases is variable by several measures, suggesting involvement of heterogeneous molecular elements. Secondary, acquired ATRA resistance occurs in most patients treated with ATRA alone and in many patients who relapse from combination ATRA chemotherapy regimens despite limited ATRA exposure. Although early studies suggested that an adaptive hypercatabolic response to pharmacological ATRA levels is the principal mechanism of ATRA resistance, recent studies suggest that molecular disturbances in APL cells have a predominant role, particularly if disease relapse occurs a few months after discontinuing ATRA therapy. This review summarizes the systemic and APL cellular elements that have been linked to clinical ATRA resistance with emphasis on identifying areas of deficient information and important topics for further investigation. Overall, the subject review strongly supports the hypothesis that, although APL is an infrequent and nearly cured disease, much can be gained by understanding the complex relationship of ATRA resistance to the progression and relapse of APL, which has important implications for other leukemias and malignancies.
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Affiliation(s)
- R E Gallagher
- Department of Oncology, Montefiore Medical Center, New York 10467, USA
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240
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Adida A, Spener F. Intracellular lipid binding proteins and nuclear receptors involved in branched-chain fatty acid signaling. Prostaglandins Leukot Essent Fatty Acids 2002; 67:91-8. [PMID: 12324226 DOI: 10.1054/plef.2002.0404] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Branched-chain fatty acids are potent regulators of gene expression. Among them are the vitamin A-derived retinoic acids, which are involved in cell growth and differentiation, and the chlorophyll-derived phytol metabolites such as phytanic and pristanic acids, which affect catabolic lipid metabolism. Gene expression regulated by these signaling molecules is mediated by two protein families. These are, on the one hand, the intracellular lipid binding proteins, i.e. cellular retinoic acid binding protein and liver-type fatty acid binding protein, which are responsible for ligand-transport to the nucleus. On the other hand are the ligand-activated nuclear receptors, i.e. the retinoic acid receptors for retinoic acids and the peroxisome proliferator-activated receptors for the phytol metabolites. In this review, we discuss the cross-talk between the two protein families and how this cross-talk contributes to targeted signaling with branched-chain fatty acids.
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Affiliation(s)
- A Adida
- Department of Biochemistry, University of Münster, Münster, Germany
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241
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Tan NS, Shaw NS, Vinckenbosch N, Liu P, Yasmin R, Desvergne B, Wahli W, Noy N. Selective cooperation between fatty acid binding proteins and peroxisome proliferator-activated receptors in regulating transcription. Mol Cell Biol 2002; 22:5114-27. [PMID: 12077340 PMCID: PMC139777 DOI: 10.1128/mcb.22.14.5114-5127.2002] [Citation(s) in RCA: 373] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Lipophilic compounds such as retinoic acid and long-chain fatty acids regulate gene transcription by activating nuclear receptors such as retinoic acid receptors (RARs) and peroxisome proliferator-activated receptors (PPARs). These compounds also bind in cells to members of the family of intracellular lipid binding proteins, which includes cellular retinoic acid-binding proteins (CRABPs) and fatty acid binding proteins (FABPs). We previously reported that CRABP-II enhances the transcriptional activity of RAR by directly targeting retinoic acid to the receptor. Here, potential functional cooperation between FABPs and PPARs in regulating the transcriptional activities of their common ligands was investigated. We show that adipocyte FABP and keratinocyte FABP (A-FABP and K-FABP, respectively) selectively enhance the activities of PPARgamma and PPARbeta, respectively, and that these FABPs massively relocate to the nucleus in response to selective ligands for the PPAR isotype which they activate. We show further that A-FABP and K-FABP interact directly with PPARgamma and PPARbeta and that they do so in a receptor- and ligand-selective manner. Finally, the data demonstrate that the presence of high levels of K-FABP in keratinocytes is essential for PPARbeta-mediated induction of differentiation of these cells. Taken together, the data establish that A-FABP and K-FABP govern the transcriptional activities of their ligands by targeting them to cognate PPARs in the nucleus, thereby enabling PPARs to exert their biological functions.
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Affiliation(s)
- Nguan-Soon Tan
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
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242
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Budhu AS, Noy N. Direct channeling of retinoic acid between cellular retinoic acid-binding protein II and retinoic acid receptor sensitizes mammary carcinoma cells to retinoic acid-induced growth arrest. Mol Cell Biol 2002; 22:2632-41. [PMID: 11909957 PMCID: PMC133717 DOI: 10.1128/mcb.22.8.2632-2641.2002] [Citation(s) in RCA: 224] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cellular retinoic acid-binding protein II (CRABP-II) is an intracellular lipid-binding protein that associates with retinoic acid with a subnanomolar affinity. We previously showed that CRABP-II enhances the transcriptional activity of the nuclear receptor with which it shares a common ligand, namely, the retinoic acid receptor (RAR), and we suggested that it may act by delivering retinoic acid to this receptor. Here, the mechanisms underlying the effects of CRABP-II on the transcriptional activity of RAR and the functional consequences of these effects were studied. We show that CRABP-II, a predominantly cytosolic protein, massively undergoes nuclear localization upon binding of retinoic acid; that it interacts with RAR in a ligand-dependent fashion; and that, in the presence of retinoic acid, the CRABP-II-RAR complex is a short-lived intermediate. The data establish that potentiation of the transcriptional activity of RAR stems directly from the ability of CRABP-II to channel retinoic acid to the receptor. We demonstrate further that overexpression of CRABP-II in MCF-7 mammary carcinoma cells dramatically enhances their sensitivity to retinoic acid-induced growth inhibition. Conversely, diminished expression of CRABP-II renders these cells retinoic acid resistant. Taken together, the data unequivocally establish the function of CRABP-II in modulating the RAR-mediated biological activities of retinoic acid.
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Affiliation(s)
- Anuradha S Budhu
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA
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243
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Lehmann S, Paul C, Törmä H. The expression of cellular retinoid binding proteins in non-APL leukemic cells and its association with retinoid sensitivity. Leuk Lymphoma 2002; 43:851-8. [PMID: 12153175 DOI: 10.1080/10428190290016999] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Retinoic acid (RA) has important effects on cell differentiation and cell growth and on normal embryonic development. Intracellular retinoid signaling induced by endogenous or exogenous RA is regulated by retinoid binding proteins such as CRBPI, CRABPI and CRABPII and there are data suggesting that the expression of these proteins can influence the sensitivity to the growth inhibitory effects of ATRA. In this study, we investigated the basal and ATRA-induced expression of CRBPI and CRABPI and II in leukemic cell lines and in cells from patients with acute myeloid leukemia (AML). CRBPI as well as CRABPI and II were expressed in all tested cell lines and in leukemic cells from all 18 AML-patients. CRABPII mRNA expression was more abundant than CRBPI and CRABPI in both the cell lines and the patient cells but the levels compared the house keeping gene was lower in the patient cells. In all cell lines and in 69% of the patient samples, ATRA did upregulate CRABPII whereas CRBPI exhibited a varying response and CRABPI was more commonly downregulated. The sensitivity to the growth inhibitory effects of ATRA did not correlate with the basal expression of any of these proteins. However, ATRA-induced upregulation of CRABPII did significantly correlate with the ATRA sensitivity (p < 0.005) as well as with ATRA-induced upregulation of the retinoid receptor RARbeta (p < 0.05). We conclude that the retinoid binding proteins CRBPI and CRABPI and II are expressed in myeloid leukemic cells of non-M3 type but that the level of expression does not affect ATRA sensitivity.
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Affiliation(s)
- S Lehmann
- Department of Hematology, Karolinska Institute, Huddinge Hospital, Stockholm, Sweden.
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244
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Karlsson T, Virtanen M, Sirsjö A, Rollman O, Vahlquist A, Törmä H. Topical retinoic acid alters the expression of cellular retinoic acid-binding protein-I and cellular retinoic acid-binding protein-II in non-lesional but not lesional psoriatic skin. Exp Dermatol 2002; 11:143-52. [PMID: 11994141 DOI: 10.1034/j.1600-0625.2002.110206.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Therapeutic retinoids have profound effects on psoriatic skin pathology but their interactions with various retinoid-binding proteins in lesional vs non-lesional skin have not been investigated. Using quantitative real-time PCR the mRNA expression of cellular retinol-binding protein I (CRBPI) and retinoic acid-binding protein I/II (CRABPI/CRABPII) was studied in psoriatic and healthy control (=normal) skin after 4 days of occlusive RA/vehicle treatment (n=6). Untreated psoriatic lesions showed a markedly elevated CRABPII/CRABPI ratio, while the CRBPI level was reduced in lesional and non-lesional skin as compared to normal skin. In RA-treated normal and non-lesional skin, the mRNA expression of CRBPI was unaltered while that of CRABPI and CRABPII was reduced by approximately 80% and increased approximately 5-fold, respectively, as compared to vehicle-treated skin. In contrast, lesional skin exposed to RA showed an almost 90% increase in CRBPI transcripts but unaltered expression of CRABPI and CRABPII, yet, the mRNA expression of several inflammatory mediators, e.g. inducible nitric oxide synthase, interferon-gamma and interleukin-1beta, was clearly reduced. Immunohistochemistry localized CRABPII to suprabasal keratinocytes in normal skin and revealed markedly elevated levels in lesional skin. RA treatment induced CRABPII protein expression in normal and non-lesional skin, to similar levels as in untreated lesions. The results indicate that the effects of RA differ in normal/non-lesional psoriatic skin and lesional skin. Whether the high expression of CRABPII in psoriatic skin lesions is due to increased amounts of endogenous retinoids in lesional skin or reflects an abnormal regulation of the CRABPII gene in psoriasis remains to be studied.
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Affiliation(s)
- T Karlsson
- Department of Medical Sciences, Section of Dermatology and Venereology, Uppsala University, Sweden
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245
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Bastie JN, Despouy G, Balitrand N, Rochette-Egly C, Chomienne C, Delva L. The novel co-activator CRABPII binds to RARalpha and RXRalpha via two nuclear receptor interacting domains and does not require the AF-2 'core'. FEBS Lett 2001; 507:67-73. [PMID: 11682061 DOI: 10.1016/s0014-5793(01)02938-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We identify the RARalpha, RXRalpha and CRABPII domains required for the physical interaction of these proteins. On RARalpha and RXRalpha, the sequences correspond to the DEF and DE domains, respectively, but the interaction with CRABPII does not require the AF-2AD 'core'. On CRABPII, two interacting domains are identified (NRID1 and NRID2), one of which contains the only enhancement transactivation domain of CRABPII. The interaction is ligand-independent and does not require the ligand-binding domain of CRABPII. These results further stress that interaction of CRABPII with the nuclear receptors defines a novel level of transcriptional control.
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Affiliation(s)
- J N Bastie
- Laboratoire de Biologie Cellulaire Hématopoïétique, Hôpital Saint-Louis, Paris, France
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246
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Bi J, Hu X, Zhou FC, Wei LN. Upregulation of cellular retinoic acid-binding protein I expression by ethanol. Dev Growth Differ 2001; 43:553-61. [PMID: 11576172 DOI: 10.1046/j.1440-169x.2001.00591.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Acute and chronic ethanol ingestion cause embryopathy similar to that of hyper- or hypovitaminosis A. Experimental data have suggested interaction between vitamin A and alcohol signaling pathways at the level of metabolic interference, which ultimately affects the concentration of retinoic acid (RA) in animals. The present study was set up to examine the possible effects of alcohol on cellular RA binding protein I (CRABP-I) expression during embryonic development by using transgenic mouse embryos and P19 embryonal carcinoma cells as experimental models. It was found that expression of the mouse CRABP-I gene was elevated in developing embryos at mid-gestation stages as a result of ethanol consumption by the mothers. Specific elevation of this gene was detected in the limb bud and the gut. In the P19 model, the CRABP-I gene was directly upregulated by ethanol, which was not blocked by a protein synthesis inhibitor. Furthermore, the regulation of the CRABP-I gene by ethanol was mediated by the 5' upstream regulatory region of the CRABP-I gene promoter. A potential interaction of vitamin A and ethanol at the level of CRABP-I gene expression is discussed.
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Affiliation(s)
- J Bi
- Department of Pharmacology, University of Minnesota School of Medicine, 6-120 Jackson Hall, 321 Church St SE, Minneapolis, MN 55455-0217, USA
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247
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Cho Y, Talmage DA. Protein kinase Calpha expression confers retinoic acid sensitivity on MDA-MB-231 human breast cancer cells. Exp Cell Res 2001; 269:97-108. [PMID: 11525643 DOI: 10.1006/excr.2001.5298] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Retinoic acid activation of retinoic acid receptor alpha (RARalpha) induces protein kinase Calpha (PKCalpha) expression and inhibits proliferation of the hormone-dependent T-47D breast cancer cell line. Retinoic acid has no effect on proliferation or PKCalpha expression in a hormone-independent, breast cancer cell line (MDA-MB-231). To test the role of PKCalpha in retinoic acid-induced growth arrest of human breast cancer cells we established MDA-MB-231 cell lines stably expressing PKCalpha. Constitutive expression of PKCalpha did not affect proliferation of MDA-MB-231 cells but did result in partial retinoic acid sensitivity. Retinoic acid treatment of PKCalpha-MDA-MB-231 cells decreased proliferation (by approximately 40%) and inhibited serum activation of MAP kinases and induction of c-fos. Similar results were seen in MDA-MB-231 cells in which transcription of the transfected PKCalpha cDNA was reversibly induced by isopropyl beta-d-thiogalactoside. Expression of RARalpha in PKCalpha expressing MDA-MB-231 cells resulted in even greater retinoic acid responses, as measured by effects on cell proliferation, inhibition of serum signaling, and transactivation of an RARE-CAT reporter plasmid. In summary, PKCalpha synergizes with activated RARalpha to disrupt serum growth factor signaling, ultimately arresting proliferation of MDA-MB-231 cells.
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MESH Headings
- Antineoplastic Agents/metabolism
- Antineoplastic Agents/pharmacology
- Blood Proteins/pharmacology
- Breast Neoplasms/drug therapy
- Breast Neoplasms/enzymology
- Breast Neoplasms/physiopathology
- Calcium/metabolism
- Cell Division/drug effects
- Cell Division/physiology
- Drug Interactions
- Epidermal Growth Factor/pharmacology
- Female
- Gene Expression Regulation, Neoplastic/drug effects
- Gene Expression Regulation, Neoplastic/physiology
- Genes, Reporter/drug effects
- Genes, Reporter/physiology
- Humans
- Isoenzymes/drug effects
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Isopropyl Thiogalactoside/pharmacology
- Mitogen-Activated Protein Kinases/genetics
- Protein Kinase C/drug effects
- Protein Kinase C/genetics
- Protein Kinase C/metabolism
- Protein Kinase C-alpha
- Proto-Oncogene Proteins c-fos/genetics
- Proto-Oncogene Proteins c-jun/genetics
- RNA, Messenger/drug effects
- RNA, Messenger/metabolism
- Receptors, Retinoic Acid/drug effects
- Receptors, Retinoic Acid/genetics
- Receptors, Retinoic Acid/metabolism
- Signal Transduction/drug effects
- Signal Transduction/physiology
- Transfection
- Tretinoin/metabolism
- Tretinoin/pharmacology
- Tumor Cells, Cultured/cytology
- Tumor Cells, Cultured/drug effects
- Tumor Cells, Cultured/enzymology
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Affiliation(s)
- Y Cho
- Institute of Human Nutrition, Columbia University, New York, New York 10032, USA
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248
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Tanaka T, Rodríguez de la Concepción ML, De Luca LM. Involvement of all-trans-retinoic acid in the breakdown of retinoic acid receptors alpha and gamma through proteasomes in MCF-7 human breast cancer cells. Biochem Pharmacol 2001; 61:1347-55. [PMID: 11331070 DOI: 10.1016/s0006-2952(01)00600-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Most studies have reported an up-regulation of retinoic acid receptor (RAR) mRNA expression by all-trans retinoic acid (RA). We aimed to study the effect of RA on RAR protein levels in MCF-7 human breast cancer cells. Incubation of these cells with 10(-6) M RA induced a rapid breakdown of both RARalpha and RARgamma in spite of the accumulation of their mRNAs. Proteasome specific inhibitors blocked the RA-induced breakdown of RARs. Furthermore, RA enhanced the formation of the complex between RARalpha and ubiquitin in a concentration- and time-dependent manner, suggesting the involvement of ubiquitin and proteasome in this reaction. Retinoid X receptor alpha (RXRalpha) was also decreased, albeit to a lesser extent, in RA-treated cells. Use of synthetic receptor agonists and antagonists clearly showed that the effect of the retinoid on the breakdown of the retinoid receptors is receptor-ligand agonist-dependent and blunted by the antagonist. An electrophoretic mobility shift assay, using nuclear extracts from RA-treated cells, showed that a reduction in complex formation with hormone response elements correlated with the reduction of RAR and RXR protein. These data suggest that RA induces the breakdown of RARs through a process involving ubiquitination and that this phenomenon causes a reduction in the formation of DNA-receptor complexes.
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Affiliation(s)
- T Tanaka
- National Cancer Institute, National Institutes of Health, Building 37, Room 3A-17, 37 Convent Drive, Bethesda, MD 20892-4255, USA
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249
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Chen Y, Pollet N, Niehrs C, Pieler T. Increased XRALDH2 activity has a posteriorizing effect on the central nervous system of Xenopus embryos. Mech Dev 2001; 101:91-103. [PMID: 11231062 DOI: 10.1016/s0925-4773(00)00558-x] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Retinoic acid (RA) metabolizing enzymes play important roles in RA signaling during vertebrate embryogenesis. We have previously reported on a RA degrading enzyme, XCYP26, which appears to be critical for the anteroposterior patterning of the central nervous system (EMBO J. 17 (1998) 7361). Here, we report on the sequence, expression and function of its counterpart, XRALDH2, a RA generating enzyme in Xenopus. During gastrulation and neurulation, XRALDH2 and XCYP26 show non-overlapping, complementary expression domains. Upon misexpression, XRALDH2 is found to reduce the forebrain territory and to posteriorize the molecular identity of midbrain and individual hindbrain rhombomeres in Xenopus embryos. Furthermore, ectopic XRALDH2, in combination with its substrate, all-trans-retinal (ATR), can mimic the RA phenotype to result in microcephalic embryos. Taken together, our data support the notion that XRALDH2 plays an important role in RA homeostasis by the creation of a critical RA concentration gradient along the anteroposterior axis of early embryos, which is essential for proper patterning of the central nervous system in Xenopus.
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Affiliation(s)
- Y Chen
- Georg-August-Universität Göttingen, Institut für Biochemie und Molekulare Zellbiologie, Humboldtallee 23, D-37073, Göttingen, Germany
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250
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Budhu A, Gillilan R, Noy N. Localization of the RAR interaction domain of cellular retinoic acid binding protein-II. J Mol Biol 2001; 305:939-49. [PMID: 11162104 DOI: 10.1006/jmbi.2000.4340] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The pleiotropic effects of retinoic acid (RA) in mammalian cells are mediated by two classes of proteins: the retinoic acid receptors (RAR), and cellular retinoic acid binding proteins (CRABP-I and CRABP-II). The high conservation across species and the differential expression patterns of the two CRABPs suggest that they serve distinct biological functions. We previously showed that CRABP-II, but not CRABP-I, delivers RA to RAR through direct protein-protein interactions between the binding protein and the receptor. "Channeling" of RA between CRABP-II and RAR markedly facilitates the formation of the holo-receptor and, as a consequence, enhances the transcriptional activity of RAR in cells. Here, we localize the region of CRABP-II that mediates the interactions of this protein with RAR. Comparison between the electrostatic surface potential of CRABP-I and II revealed the presence of a sole region displaying a dramatic potential change between the two isoforms. Examination of the underlying model revealed that the change stemmed from CRABP-I/CRABP-II substitution of three spatially aligned residues E75Q, K81P, and E102 K, located on a protrusion above the entrance to the ligand binding pocket of the protein. Substituting the corresponding CRABP-II residues onto CRABP-I conferred upon this protein the ability to channel RA to RAR and to enhance the transcriptional activity of RAR in cells. Conversely, converting these amino acid residues in CRABP-II to the homologous CRABP-I residues resulted in loss of the ability of CRABP-II to interact with RAR and to augment the receptor's activity. The data demonstrate that the surface region of CRABP-II containing residues Gln75, Pro81, and Lys102 is necessary and sufficient for mediating the interactions of this protein with RAR, facilitating the formation of the holo-receptor, and enhancing the transcriptional activity of RA.
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Affiliation(s)
- A Budhu
- Division of Nutritional Sciences, Cornell Theory Center, Cornell University, Ithaca, NY 14853, USA
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