1
|
Abstract
2-Oxoglutarate-dependent dioxygenases (2OGDDs) are a superfamily of enzymes that play diverse roles in many biological processes, including regulation of hypoxia-inducible factor-mediated adaptation to hypoxia, extracellular matrix formation, epigenetic regulation of gene transcription and the reprogramming of cellular metabolism. 2OGDDs all require oxygen, reduced iron and 2-oxoglutarate (also known as α-ketoglutarate) to function, although their affinities for each of these co-substrates, and hence their sensitivity to depletion of specific co-substrates, varies widely. Numerous 2OGDDs are recurrently dysregulated in cancer. Moreover, cancer-specific metabolic changes, such as those that occur subsequent to mutations in the genes encoding succinate dehydrogenase, fumarate hydratase or isocitrate dehydrogenase, can dysregulate specific 2OGDDs. This latter observation suggests that the role of 2OGDDs in cancer extends beyond cancers that harbour mutations in the genes encoding members of the 2OGDD superfamily. Herein, we review the regulation of 2OGDDs in normal cells and how that regulation is corrupted in cancer.
Collapse
Affiliation(s)
- Julie-Aurore Losman
- Department of Medical Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Boston, MA, USA
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Peppi Koivunen
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, Oulu Center for Cell-Matrix Research, University of Oulu, Oulu, Finland
| | - William G Kaelin
- Department of Medical Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Boston, MA, USA.
- Howard Hughes Medical Institute (HHMI), Chevy Chase, MD, USA.
| |
Collapse
|
2
|
Yan L, Liu Y. Insights into the Mechanism and Enantioselectivity in the Biosynthesis of Ergot Alkaloid Cycloclavine Catalyzed by Aj_EasH from Aspergillus japonicus. Inorg Chem 2019; 58:13771-13781. [PMID: 31560525 DOI: 10.1021/acs.inorgchem.9b01168] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Cycloclavine is a complex ergot alkaloid containing an unusual cyclopropyl moiety, which has a wide range of biological activities and pharmaceutical applications. The biosynthesis of cycloclavine requires a series of enzymes, one of which is a nonheme FeII/α-ketoglutarate-dependent (aKG) oxidase (Aj_EasH). According to the previous proposal, the cyclopropyl ring formation catalyzed by Aj_EasH follows an unprecedented oxidative mechanism; however, the reaction details are unknown. In this article, on the basis of the recently obtained crystal structure of Aj_EasH (EasH from Aspergillus japonicas), the reactant models were built, and the reaction details were investigated by performing QM-only and combined QM and MM calculations. Our calculation results reveal that the biosynthesis of cyclopropyl moiety involves a radical intermediate rather than a carbocationic or carbanionic intermediate as in the biosynthesis of terpenoid family. The iron(IV)-oxo first abstracts a hydrogen atom from the substrate to trigger the reaction, and then the generated radical intermediate undergoes ring rearrangement to form the fused 5-3 ring system of cycloclavine. On the basis of our calculations, the absolute configuration of the cycloclavine catalyzed by Aj_EasH from Aspergillus japonicus should be (5R,8R,10R), which is different from the product isolated from Ipomoea hildebrandtii (5R,8S,10S). Residues at the active site play an important role in substrate binding, ring rearrangement, and enantioselectivity.
Collapse
Affiliation(s)
- Lijuan Yan
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering , Shandong University , Jinan , Shandong 250100 , China
| | - Yongjun Liu
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering , Shandong University , Jinan , Shandong 250100 , China
| |
Collapse
|
3
|
Wang X, Su H, Liu Y. Insights into the unprecedented epoxidation mechanism of fumitremorgin B endoperoxidase (FtmOx1) from Aspergillus fumigatus by QM/MM calculations. Phys Chem Chem Phys 2017; 19:7668-7677. [DOI: 10.1039/c7cp00313g] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
QM/MM calculations indicate that the quintet of the FeIVO complex firstly abstracts the hydrogen from Tyr228 to initiate the reaction, then the generated Tyr228 radical extracts the hydrogen from C21 to form the C21 radical, which binds the second dioxygen to complete the epoxidation.
Collapse
Affiliation(s)
- Xiya Wang
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
- China
| | - Hao Su
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
- China
| | - Yongjun Liu
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
- China
| |
Collapse
|
4
|
Klouwer FCC, Koster J, Ferdinandusse S, Waterham HR. Peroxisomal abnormalities in the immortalized human hepatocyte (IHH) cell line. Histochem Cell Biol 2016; 147:537-541. [PMID: 28013369 PMCID: PMC5359384 DOI: 10.1007/s00418-016-1532-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2016] [Indexed: 12/01/2022]
Abstract
The immortalized human hepatocyte (IHH) cell line is increasingly used for studies related to liver metabolism, including hepatic glucose, lipid, lipoprotein and triglyceride metabolism, and the effect of therapeutic interventions. To determine whether the IHH cell line is a good model to investigate hepatic peroxisomal metabolism, we measured several peroxisomal parameters in IHH cells and, for comparison, HepG2 cells and primary skin fibroblasts. This revealed a marked plasmalogen deficiency and a deficient fatty acid α-oxidation in the IHH cells, due to a defect of PEX7, a cytosolic receptor protein required for peroxisomal import of a subset of peroxisomal proteins. These abnormalities have consequences for the lipid homeostasis of these cells and thus should be taken into account for the interpretation of data previously generated by using this cell line and when considering using this cell line for future research.
Collapse
Affiliation(s)
- Femke C C Klouwer
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.,Department of Pediatric Neurology, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Janet Koster
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Hans R Waterham
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| |
Collapse
|
5
|
Kundu S. Co-operative intermolecular kinetics of 2-oxoglutarate dependent dioxygenases may be essential for system-level regulation of plant cell physiology. FRONTIERS IN PLANT SCIENCE 2015; 6:489. [PMID: 26236316 PMCID: PMC4502536 DOI: 10.3389/fpls.2015.00489] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 06/19/2015] [Indexed: 05/24/2023]
Abstract
Can the stimulus-driven synergistic association of 2-oxoglutarate dependent dioxygenases be influenced by the kinetic parameters of binding and catalysis?In this manuscript, I posit that these indices are necessary and specific for a particular stimulus, and are key determinants of a dynamic clustering that may function to mitigate the effects of this trigger. The protein(s)/sequence(s) that comprise this group are representative of all major kingdoms of life, and catalyze a generic hydroxylation, which is, in most cases accompanied by a specialized conversion of the substrate molecule. Iron is an essential co-factor for this transformation and the response to waning levels is systemic, and mandates the simultaneous participation of molecular sensors, transporters, and signal transducers. Here, I present a proof-of-concept model, that an evolving molecular network of 2OG-dependent enzymes can maintain iron homeostasis in the cytosol of root hair cells of members of the family Gramineae by actuating a non-reductive compensatory chelation by the phytosiderophores. Regression models of empirically available kinetic data (iron and alpha-ketoglutarate) were formulated, analyzed, and compared. The results, when viewed in context of the superfamily responding as a unit, suggest that members can indeed, work together to accomplish system-level function. This is achieved by the establishment of transient metabolic conduits, wherein the flux is dictated by kinetic compatibility of the participating enzymes. The approach adopted, i.e., predictive mathematical modeling, is integral to the hypothesis-driven acquisition of experimental data points and, in association with suitable visualization aids may be utilized for exploring complex plant biochemical systems.
Collapse
Affiliation(s)
- Siddhartha Kundu
- *Correspondence: Siddhartha Kundu, School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Mehrauli Road, New Delhi 110067, India ;
| |
Collapse
|
6
|
Matsuda Y, Awakawa T, Wakimoto T, Abe I. Spiro-Ring Formation is Catalyzed by a Multifunctional Dioxygenase in Austinol Biosynthesis. J Am Chem Soc 2013; 135:10962-5. [DOI: 10.1021/ja405518u] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Yudai Matsuda
- Graduate School of Pharmaceutical
Sciences, The University of Tokyo, 7-3-1
Hongo, Bunkyo-ku, Tokyo
113-0033, Japan
| | - Takayoshi Awakawa
- Graduate School of Pharmaceutical
Sciences, The University of Tokyo, 7-3-1
Hongo, Bunkyo-ku, Tokyo
113-0033, Japan
| | - Toshiyuki Wakimoto
- Graduate School of Pharmaceutical
Sciences, The University of Tokyo, 7-3-1
Hongo, Bunkyo-ku, Tokyo
113-0033, Japan
| | - Ikuro Abe
- Graduate School of Pharmaceutical
Sciences, The University of Tokyo, 7-3-1
Hongo, Bunkyo-ku, Tokyo
113-0033, Japan
| |
Collapse
|
7
|
Steffan N, Grundmann A, Afiyatullov S, Ruan H, Li SM. FtmOx1, a non-heme Fe(II) and alpha-ketoglutarate-dependent dioxygenase, catalyses the endoperoxide formation of verruculogen in Aspergillus fumigatus. Org Biomol Chem 2009; 7:4082-7. [PMID: 19763315 DOI: 10.1039/b908392h] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Verruculogen is a tremorgenic mycotoxin and contains an endoperoxide bond. In this study, we describe the cloning, overexpression and purification of a non-heme Fe(ii) and alpha-ketoglutarate-dependent dioxygenase FtmOx1 from Aspergillus fumigatus, which catalyses the conversion of fumitremorgin B to verruculogen by inserting an endoperoxide bond between two prenyl moieties. Incubation with (18)O(2)-enriched atmosphere demonstrated that both oxygen atoms of the endoperoxide bond are derived from one molecule of O(2). FtmOx1 is the first endoperoxide-forming non-heme Fe(ii) and alpha-ketoglutarate-dependent dioxygenase reported so far. A mechanism of FtmOx1-catalysed verruculogen formation is postulated and discussed.
Collapse
Affiliation(s)
- Nicola Steffan
- Philipps-Universität Marburg, Institut für Pharmazeutische Biologie, Deutschhausstrasse 17A, D-35037, Marburg, Germany
| | | | | | | | | |
Collapse
|
8
|
Jansen GA, Wanders RJA. Alpha-Oxidation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:1403-12. [PMID: 16934890 DOI: 10.1016/j.bbamcr.2006.07.012] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Accepted: 07/24/2006] [Indexed: 11/15/2022]
Abstract
Phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) is a branched chain fatty acid, which is a constituent of the human diet. The presence of the 3-methyl group of phytanic acid prevents degradation by beta-oxidation. Instead, the terminal carboxyl group is first removed by alpha-oxidation. The mechanism of the alpha-oxidation pathway and the enzymes involved are described in this review.
Collapse
Affiliation(s)
- Gerbert A Jansen
- Bioinformatics Laboratory, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Academic Medical Centre, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.
| | | |
Collapse
|
9
|
McDonough MA, Kavanagh KL, Butler D, Searls T, Oppermann U, Schofield CJ. Structure of human phytanoyl-CoA 2-hydroxylase identifies molecular mechanisms of Refsum disease. J Biol Chem 2005; 280:41101-10. [PMID: 16186124 DOI: 10.1074/jbc.m507528200] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Refsum disease (RD), a neurological syndrome characterized by adult onset retinitis pigmentosa, anosmia, sensory neuropathy, and phytanic acidaemia, is caused by elevated levels of phytanic acid. Many cases of RD are associated with mutations in phytanoyl-CoA 2-hydroxylase (PAHX), an Fe(II) and 2-oxoglutarate (2OG)-dependent oxygenase that catalyzes the initial alpha-oxidation step in the degradation of phytenic acid in peroxisomes. We describe the x-ray crystallographic structure of PAHX to 2.5 A resolution complexed with Fe(II) and 2OG and predict the molecular consequences of mutations causing RD. Like other 2OG oxygenases, PAHX possesses a double-stranded beta-helix core, which supports three iron binding ligands (His(175), Asp(177), and His(264)); the 2-oxoacid group of 2OG binds to the Fe(II) in a bidentate manner. The manner in which PAHX binds to Fe(II) and 2OG together with the presence of a cysteine residue (Cys(191)) 6.7 A from the Fe(II) and two further histidine residues (His(155) and His(281)) at its active site distinguishes it from that of the other human 2OG oxygenase for which structures are available, factor inhibiting hypoxia-inducible factor. Of the 15 PAHX residues observed to be mutated in RD patients, 11 cluster in two distinct groups around the Fe(II) (Pro(173), His(175), Gln(176), Asp(177), and His(220)) and 2OG binding sites (Trp(193), Glu(197), Ile(199), Gly(204), Asn(269), and Arg(275)). PAHX may be the first of a new subfamily of coenzyme A-binding 2OG oxygenases.
Collapse
Affiliation(s)
- Michael A McDonough
- Oxford Centre for Molecular Sciences and Department of Chemistry, University of Oxford, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | | | | | | | | | | |
Collapse
|
10
|
Jansen GA, Waterham HR, Wanders RJA. Molecular basis of Refsum disease: sequence variations in phytanoyl-CoA hydroxylase (PHYH) and the PTS2 receptor (PEX7). Hum Mutat 2004; 23:209-18. [PMID: 14974078 DOI: 10.1002/humu.10315] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Refsum disease has long been known to be an inherited disorder of lipid metabolism characterized by the accumulation of phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) caused by an alpha-oxidation deficiency of this branched chain fatty acid in peroxisomes. The mechanism of phytanic acid alpha-oxidation and the enzymes involved had long remained mysterious, but they have been resolved in recent years. This has led to the resolution of the molecular basis of Refsum disease. Interestingly, Refsum disease is genetically heterogeneous; two genes, PHYH (also named PAHX) and PEX7, have been identified to cause Refsum disease, as reviewed in this work.
Collapse
Affiliation(s)
- Gerbert A Jansen
- Laboratory of Genetic Metabolic Diseases, Department of Clinical Chemistry, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | | | | |
Collapse
|
11
|
Mukherji M, Schofield CJ, Wierzbicki AS, Jansen GA, Wanders RJA, Lloyd MD. The chemical biology of branched-chain lipid metabolism. Prog Lipid Res 2003; 42:359-76. [PMID: 12814641 DOI: 10.1016/s0163-7827(03)00016-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mammalian metabolism of some lipids including 3-methyl and 2-methyl branched-chain fatty acids occurs within peroxisomes. Such lipids, including phytanic and pristanic acids, are commonly found within the human diet and may be derived from chlorophyll in plant extracts. Due to the presence of a methyl group at its beta-carbon, the well-characterised beta-oxidation pathway cannot degrade phytanic acid. Instead its alpha-methylene group is oxidatively excised to give pristanic acid, which can be metabolised by the beta-oxidation pathway. Many defects in the alpha-oxidation pathway result in an accumulation of phytanic acid, leading to neurological distress, deterioration of vision, deafness, loss of coordination and eventual death. Details of the alpha-oxidation pathway have only recently been elucidated, and considerable progress has been made in understanding the detailed enzymology of one of the oxidative steps within this pathway. This review summarises these recent advances and considers the roles and likely mechanisms of the enzymes within the alpha-oxidation pathway.
Collapse
Affiliation(s)
- Mridul Mukherji
- The Oxford Centre for Molecular Sciences & The Dyson Perrins Laboratory, South Parks Road, Oxford OX1 3QY, UK
| | | | | | | | | | | |
Collapse
|
12
|
Wanders RJA, Jansen GA, Lloyd MD. Phytanic acid alpha-oxidation, new insights into an old problem: a review. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1631:119-35. [PMID: 12633678 DOI: 10.1016/s1388-1981(03)00003-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Phytanic acid (3,7,10,14-tetramethylhexadecanoic acid) is a branched-chain fatty acid which is known to accumulate in a number of different genetic diseases including Refsum disease. Due to the presence of a methyl-group at the 3-position, phytanic acid and other 3-methyl fatty acids can not undergo beta-oxidation but are first subjected to fatty acid alpha-oxidation in which the terminal carboxyl-group is released as CO(2). The mechanism of alpha-oxidation has long remained obscure but has been resolved in recent years. Furthermore, peroxisomes have been found to play an indispensable role in fatty acid alpha-oxidation, and the complete alpha-oxidation machinery is probably localized in peroxisomes. This Review describes the current state of knowledge about fatty acid alpha-oxidation in mammals with particular emphasis on the mechanism involved and the enzymology of the pathway.
Collapse
Affiliation(s)
- Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Department of Pediatrics/Emma Children's Hospital and Clinical Chemistry, Academic Medical Centre, University Hospital Amsterdam, Room F0-224, P.O. Box 22700, 1100 DE Amsterdam, The Netherlands.
| | | | | |
Collapse
|
13
|
Mukherji M, Kershaw NJ, Schofield CJ, Wierzbicki AS, Lloyd MD. Utilization of sterol carrier protein-2 by phytanoyl-CoA 2-hydroxylase in the peroxisomal alpha oxidation of phytanic acid. CHEMISTRY & BIOLOGY 2002; 9:597-605. [PMID: 12031666 DOI: 10.1016/s1074-5521(02)00139-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Since it possesses a 3-methyl group, phytanic acid is degraded by a peroxisomal alpha-oxidation pathway, the first step of which is catalyzed by phytanoyl-CoA 2-hydroxylase (PAHX). Mutations in human PAHX cause phytanic acid accumulations leading to Adult Refsum's Disease (ARD), which is also observed in a sterol carrier protein 2 (SCP-2)-deficient mouse model. Phytanoyl-CoA is efficiently 2-hydroxylated by PAHX in vitro in the presence of mature SCP-2. Other straight-chain fatty acyl-CoA esters were also 2-hydroxylated and the products isolated and characterized. Use of SCP-2 increases discrimination between straight-chain (e.g., hexadecanoyl-CoA) and branched-chain (e.g., phytanoyl-CoA) substrates by PAHX. The results explain the phytanic acid accumulation in the SCP-2-deficient mouse model and suggest that some of the common symptoms of ARD and other peroxisomal diseases may arise in part due to defects in SCP-2 function caused by increased phytanic acid levels.
Collapse
Affiliation(s)
- Mridul Mukherji
- The Oxford Centre for Molecular Science, The Dyson Perrins Laboratory, South Parks Road, OX1 3QY, Oxford, United Kingdom
| | | | | | | | | |
Collapse
|
14
|
Phytanoyl-CoA Hydroxylase Deficiency. CURRENT VIEWS OF FATTY ACID OXIDATION AND KETOGENESIS 2002. [DOI: 10.1007/0-306-46818-2_43] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
|
15
|
Zomer AW, Jansen GA, Van Der Burg B, Verhoeven NM, Jakobs C, Van Der Saag PT, Wanders RJ, Poll-The BT. Phytanoyl-CoA hydroxylase activity is induced by phytanic acid. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:4063-7. [PMID: 10866807 DOI: 10.1046/j.1432-1327.2000.01451.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) is a branched-chain fatty acid present in various dietary products such as milk, cheese and fish. In patients with Refsum disease, accumulation of phytanic acid occurs due to a deficiency of phytanoyl-CoA hydroxylase, a peroxisomal enzyme containing a peroxisomal targeting signal 2. Recently, phytanoyl-CoA hydroxylase cDNA has been isolated and functional mutations have been identified. As it has been shown that phytanic acid activates the nuclear hormone receptors peroxisome proliferator-activated receptor (PPAR)alpha and all three retinoid X receptors (RXRs), the intracellular concentration of this fatty acid should be tightly regulated. When various cell lines were grown in the presence of phytanic acid, the activity of phytanoyl-CoA hydroxylase increased up to four times, depending on the particular cell type. In one cell line, HepG2, no induction of phytanoyl-CoA hydroxylase activity was observed. After addition of phytanic acid to COS-1 cells, an increase in phytanoyl-CoA hydroxylase activity was observed within 2 h, indicating a quick cell response. No stimulation of phytanoyl-CoA hydroxylase was observed when COS-1 cells were grown in the presence of clofibric acid, 9-cis-retinoic acid or both ligands together. This indicates that the activation of phytanoyl-CoA hydroxylase is not regulated via PPARalpha or RXR. However, stimulation of PPARalpha and all RXRs by clofibric acid and 9-cis-retinoic acid was observed in transient transfection assays. These results suggest that the induction of phytanoyl-CoA hydroxylase by phytanic acid does not proceed via one of the nuclear hormone receptors, RXR or PPARalpha.
Collapse
Affiliation(s)
- A W Zomer
- Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht, the Netherlands
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Jansen GA, Denis S, Verhoeven NM, Jakobs C, Wanders RJ. Phytanic acid alpha-oxidation in man: identification of 2-hydroxyphytanoyl-CoA lyase, a peroxisomal enzyme with normal activity in Zellweger syndrome. J Inherit Metab Dis 2000; 23:421-4. [PMID: 10896309 DOI: 10.1023/a:1005672406773] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- G A Jansen
- University of Amsterdam, Academic Medical Centre, Department of Clinical Chemistry, Emma Children's Hospital, The Netherlands
| | | | | | | | | |
Collapse
|
17
|
Jansen GA, Ofman R, Denis S, Ferdinandusse S, Hogenhout EM, Jakobs C, Wanders RJ. Phytanoyl-CoA hydroxylase from rat liver: protein purification and cDNA cloning with implications for the subcellular localization of phytanic acid α-oxidation. J Lipid Res 1999. [DOI: 10.1016/s0022-2275(20)32099-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|