51
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Ning G, Ouyang H, Wang S, Chen X, Xu B, Yang J, Zhang H, Zhang M, Xia G. 3',5'-cyclic adenosine monophosphate response element binding protein up-regulated cytochrome P450 lanosterol 14alpha-demethylase expression involved in follicle-stimulating hormone-induced mouse oocyte maturation. Mol Endocrinol 2008; 22:1682-94. [PMID: 18467523 DOI: 10.1210/me.2007-0480] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Cytochrome P450 lanosterol 14alpha-demethylase (CYP51) is a key enzyme in sterols and steroids biosynthesis that can induce meiotic resumption in mouse oocytes. The present study investigated the expression mechanism and function of CYP51 during FSH-induced mouse cumulus oocyte complexes (COCs) meiotic resumption. FSH increased cAMP-dependent protein kinase (PKA) RIIbeta level and induced cAMP response element-binding protein (CREB) phosphorylation and CYP51 expression in cumulus cells before oocyte meiotic resumption. Moreover, CYP51 and epidermal growth factor (EGF)-like factor [amphiregulin (AR)] expression were blocked by (2)-naphthol-AS-Ephosphate (KG-501) (a drug interrupting the formation of CREB functional complex). KG-501 and RS21607 (a specific inhibitor of CYP51 activity) inhibited oocyte meiotic resumption, which can be partially rescued by progesterone. These two inhibitors also inhibited FSH-induced MAPK phosphorylation. EGF could rescue the suppression by KG-501 but not RS21607. Furthermore, type II PKA analog pairs, N(6)-monobutyryl-cAMP plus 8-bromo-cAMP, increased PKA RIIbeta level and mimicked the action of FSH, including CREB phosphorylation, AR and CYP51 expression, MAPK activation, and oocyte maturation. All these data suggest that CYP51 plays a critical role in FSH-induced meiotic resumption of mouse oocytes. CYP51 and AR gene expression in cumulus cells are triggered by FSH via a type II PKA/CREB-dependent signal pathway. Our study also implicates that CYP51 activity in cumulus cells participates in EGF receptor signaling-regulated oocyte meiotic resumption.
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Affiliation(s)
- Gang Ning
- State Key Laboratories for AgroBiotechnology and Department of Animal Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, PR China
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52
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Knutson SK, Chyla BJ, Amann JM, Bhaskara S, Huppert SS, Hiebert SW. Liver-specific deletion of histone deacetylase 3 disrupts metabolic transcriptional networks. EMBO J 2008; 27:1017-28. [PMID: 18354499 PMCID: PMC2323257 DOI: 10.1038/emboj.2008.51] [Citation(s) in RCA: 209] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Accepted: 02/25/2008] [Indexed: 01/04/2023] Open
Abstract
Histone deacetylase 3 (Hdac3) is an enzymatic component of transcriptional repression complexes recruited by the nuclear hormone receptors. Inactivation of Hdac3 in cancer cell lines triggered apoptosis, and removal of Hdac3 in the germ line of mice caused embryonic lethality. Therefore, we deleted Hdac3 in the postnatal mouse liver. These mice developed hepatomegaly, which was the result of hepatocyte hypertrophy, and these morphological changes coincided with significant imbalances between carbohydrate and lipid metabolism. Loss of Hdac3 triggered changes in gene expression consistent with inactivation of repression mediated by nuclear hormone receptors. Loss of Hdac3 also increased the levels of Ppar gamma2, and treatment of these mice with a Ppar gamma antagonist partially reversed the lipid accumulation in the liver. In addition, gene expression analysis identified mammalian target of rapamycin signalling as being activated after deletion of Hdac3, and inhibition by rapamycin affected the accumulation of neutral lipids in Hdac3-null livers. Thus, Hdac3 regulates metabolism through multiple signalling pathways in the liver, and deletion of Hdac3 disrupts normal metabolic homeostasis.
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Affiliation(s)
- Sarah K Knutson
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Brenda J Chyla
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Joseph M Amann
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Srividya Bhaskara
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Stacey S Huppert
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Scott W Hiebert
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
- Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN, USA
- Department of Biochemistry, Vanderbilt University School of Medicine, 512 Preston Research Building, 23rd and Pierce Avenue, Nashville, TN 37232, USA. Tel.: +1 615 936 3582; Fax: +1 615 936 1790; E-mail:
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53
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Abstract
Cholesterol is an essential structural component in the cell membranes of most vertebrates. The biophysical properties of cholesterol and the enzymology of cholesterol metabolism provide the basis for how cells handle cholesterol and exchange it with one another. A tightly controlled--but only partially characterized--network of cellular signalling and lipid transfer systems orchestrates the functional compartmentalization of this lipid within and between organellar membranes. This largely dictates the exchange of cholesterol between tissues at the whole body level. Increased understanding of these processes and their integration at the organ systems level provides fundamental insights into the physiology of cholesterol trafficking.
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Affiliation(s)
- Elina Ikonen
- Institute of Biomedicine/Anatomy, University of Helsinki, Haartmaninkatu 8, University of Helsinki, Helsinki FI-00014, Finland.
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54
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Korošec T, Ačimovič J, Seliškar M, Kocjan D, Tacer KF, Rozman D, Urleb U. Novel cholesterol biosynthesis inhibitors targeting human lanosterol 14α-demethylase (CYP51). Bioorg Med Chem 2008; 16:209-21. [DOI: 10.1016/j.bmc.2007.10.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 09/15/2007] [Accepted: 10/01/2007] [Indexed: 11/29/2022]
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55
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Moe M, Meuwissen T, Lien S, Bendixen C, Wang X, Conley LN, Berget I, Tajet H, Grindflek E. Gene expression profiles in testis of pigs with extreme high and low levels of androstenone. BMC Genomics 2007; 8:405. [PMID: 17988377 PMCID: PMC2204014 DOI: 10.1186/1471-2164-8-405] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Accepted: 11/07/2007] [Indexed: 01/06/2023] Open
Abstract
Background: Boar taint is a major obstacle when using uncastrated male pigs for swine production. One of the main compounds causing this taint is androstenone, a pheromone produced in porcine testis. Here we use microarrays to study the expression of thousands of genes simultaneously in testis of high and low androstenone boars. The study allows identification of genes and pathways associated with elevated androstenone levels, which is essential for recognising potential molecular markers for breeding purposes. Results: Testicular tissue was collected from 60 boars, 30 with extreme high and 30 with extreme low levels of androstenone, from each of the two breeds Duroc and Norwegian Landrace. The samples were hybridised to porcine arrays containing 26,877 cDNA clones, detecting 563 and 160 genes that were differentially expressed (p < 0.01) in Duroc and Norwegian Landrace, respectively. Of these significantly up- and down-regulated clones, 72 were found to be common for the two breeds, suggesting the possibility of both general and breed specific mechanisms in regulation of, or response to androstenone levels in boars. Ten genes were chosen for verification of expression patterns by quantitative real competitive PCR and real-time PCR. As expected, our results point towards steroid hormone metabolism and biosynthesis as important biological processes for the androstenone levels, but other potential pathways were identified as well. Among these were oxidoreductase activity, ferric iron binding, iron ion binding and electron transport activities. Genes belonging to the cytochrome P450 and hydroxysteroid dehydrogenase families were highly up-regulated, in addition to several genes encoding different families of conjugation enzymes. Furthermore, a number of genes encoding transcription factors were found both up- and down-regulated. The high number of clones belonging to ferric iron and iron ion binding suggests an importance of these genes, and the association between these pathways and androstenone levels is not previously described. Conclusion: This study contributes to the understanding of the complex genetic system controlling and responding to androstenone levels in pig testis. The identification of new pathways and genes involved in the biosynthesis and metabolism of androstenone is an important first step towards finding molecular markers to reduce boar taint.
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Affiliation(s)
- Maren Moe
- The Norwegian Pig Breeders Association (NORSVIN), Hamar, Norway.
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56
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Shumyantseva VV, Bulko TV, Kuznetsova GP, Lisitsa AV, Ponomarenko EA, Karuzina II, Archakov AI. Electrochemical reduction of sterol-14α-demethylase from Mycobacterium tuberculosis (CYP51b1). BIOCHEMISTRY (MOSCOW) 2007; 72:658-63. [PMID: 17630911 DOI: 10.1134/s0006297907060090] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The electrochemical reduction of the heme protein sterol-14alpha-demethylase from Mycobacterium tuberculosis (CYP51b1, or further CYP51) was investigated. Direct electron transfer was demonstrated between CYP51 and graphite screen-printed electrodes modified with gold nanoparticles and with the membrane-like synthetic surfactant didodecyl dimethylammonium bromide. The formal potential of the Fe3+/Fe2+ pair, E(1/2), is equal to -273 mV (vs. Ag/AgCl). The cathodic current corresponding to the reduction of oxygen by immobilized heme protein was registered in the presence of oxygen. Addition of lanosterol, one of the substrates of the CYP51 family, to the oxygenated solution caused a concentration-dependent increase in the reduction current in voltammetric and amperometric experiments. Ketoconazole, an inhibitor of CYP51, inhibited the catalytic cathodic current in the presence of lanosterol. Electrochemical reduction of CYP51 may serve as an adequate alternative to the reconstituted system, which requires additional redox partners for the exhibition of catalytic activity of heme proteins of the cytochrome P450 superfamily.
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Affiliation(s)
- V V Shumyantseva
- Orekhovich Institute of Biomedical Chemistry, Russian Academy of Medical Sciences, Moscow 119121, Russia.
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57
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Abstract
By participating in pathways of cholesterol biosynthesis and elimination, different cytochrome P450 (P450 or CYP) enzymes play an important role in maintenance of cholesterol homeostasis. CYP51 is involved in cholesterol biosynthesis, whereas CYP 7A1, 27A1, 46A1, 7B1, 39A1, and 8B1 are the key enzymes in cholesterol catabolism to bile acids, the major route of cholesterol elimination in mammals. Cholesterol transformations to steroid hormones are also initiated by the P450 enzyme CYP11A1. Finally, one of the major drug-metabolizing P450s CYP3A4 seems to contribute to bile acid biosynthesis as well. The 9 P450s will be the focus of this review and assessed as drug targets for cholesterol lowering.
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Affiliation(s)
- Irina A Pikuleva
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-1031, USA.
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58
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Kojima M, Tagami T, Degawa M. Cloning of chicken lanosterol 14alpha-demethylase (CYP51) cDNA: discovery of a testis-specific CYP51 transcript. Comp Biochem Physiol A Mol Integr Physiol 2006; 145:383-9. [PMID: 16945562 DOI: 10.1016/j.cbpa.2006.07.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Revised: 07/15/2006] [Accepted: 07/20/2006] [Indexed: 11/17/2022]
Abstract
A lanosterol 14alpha-demethylase (CYP51) cDNA, which consisted of a 1419 bp open reading frame encoding 472 amino acids and a 918 bp 3'-untranslated region, was isolated from the chicken testis. The sequence corresponding to exon 1 of this cDNA was completely different from those of CYP51 cDNAs in other tissues, including the liver. The expression level of the CYP51 gene with the testis-specific exon 1 was much higher in mature (2-year-old) male chickens than in immature (5-week-old) chickens. In addition, a CYP51 transcript common to several tissues, including the liver, adrenal gland, cerebellum, cerebrum, lobus opticus, kidney, lung, heart, muscle, spleen, small intestine and ovary, was also detected in the testis by RT-PCR. Furthermore, testis-specific shorter transcripts, which have been observed in mammals such as humans, rats and pigs, were not detected in the chicken testis. The results of this study demonstrate for the first time the presence of a chicken testis-specific CYP51 transcript and its sexual maturation-related expression, although its biological significance remains unclear.
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Affiliation(s)
- Misaki Kojima
- Laboratory of Animal Gene Function, Department of Physiology and Gene Regulation, Institute of Insect and Animal Sciences, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba 305-8602, Japan.
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59
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Tan X, Behari J, Cieply B, Michalopoulos GK, Monga SPS. Conditional deletion of beta-catenin reveals its role in liver growth and regeneration. Gastroenterology 2006; 131:1561-72. [PMID: 17101329 DOI: 10.1053/j.gastro.2006.08.042] [Citation(s) in RCA: 283] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2006] [Accepted: 07/19/2006] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS The Wnt/beta-catenin pathway plays a role in liver growth and development. To address this conclusively, we used a conditional knockout approach to delete beta-catenin in the liver. METHODS Floxed beta-catenin (exons 2-6) mice were intercrossed with Albumin-Cre recombinase transgenic mice; considerable beta-catenin deletion was evident 15 days after birth by Western blot and immunohistochemistry analyses. RESULTS Although these mice were viable, there was a significant decrease in their liver weight/body weight ratio by 14% at 1 month and 28%-35% by 2-6 months of age, which was sustained throughout their normal life span. There was an accompanying decrease in basal hepatocyte proliferation showed by Ki-67 staining. Additional analysis revealed several known and novel genes to be down-regulated in these mice that play a role in normal liver homeostasis. When subjected to two-thirds partial hepatectomy, the Ctnnb1(loxp/loxp); Alb-Cre(+/-) mice were sick and lethargic, especially during the first 2-3 days only. These mice display a 2-fold decrease in the number of Ki-67- or PCNA-positive cells at the time of peak hepatocyte proliferation at 40 hours, which coincided with decreased cyclin A, D, and E expression. However, a rebound increase in hepatocyte proliferation was evident in the knockout mice at 3 days. Also, increased apoptosis was observed in the knockout livers during regeneration at all stages. CONCLUSIONS Thus, beta-catenin is essential for normal liver growth and development. Also, although regeneration is delayed in the absence of beta-catenin, it does occur suboptimally, showing its redundancy in the liver.
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Affiliation(s)
- Xinping Tan
- Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA
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60
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Lepesheva GI, Waterman MR. Sterol 14alpha-demethylase cytochrome P450 (CYP51), a P450 in all biological kingdoms. Biochim Biophys Acta Gen Subj 2006; 1770:467-77. [PMID: 16963187 PMCID: PMC2324071 DOI: 10.1016/j.bbagen.2006.07.018] [Citation(s) in RCA: 297] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2006] [Revised: 07/21/2006] [Accepted: 07/31/2006] [Indexed: 11/22/2022]
Abstract
The CYP51 family is an intriguing subject for fundamental P450 structure/function studies and is also an important clinical drug target. This review updates information on the variety of the CYP51 family members, including their physiological roles, natural substrates and substrate preferences, and catalytic properties in vitro. We present experimental support for the notion that specific conserved regions in the P450 sequences represent a CYP51 signature. Two possible roles of CYP51 in P450 evolution are discussed and the major approaches for CYP51 inhibition are summarized.
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Affiliation(s)
- Galina I Lepesheva
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA
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61
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Abstract
PURPOSE OF REVIEW P450 oxidoreductase deficiency--a newly described form of congenital adrenal hyperplasia--typically presents a steroid profile suggesting combined deficiencies of steroid 21-hydroxylase and 17alpha-hydroxylase/17,20-lyase activities. These and other enzymes require electron donation from P450 oxidoreductase. The clinical spectrum of P450 oxidoreductase deficiency ranges from severely affected children with ambiguous genitalia, adrenal insufficiency and the Antley-Bixler skeletal malformation syndrome to mildly affected individuals with polycystic ovary syndrome. We review current knowledge of P450 oxidoreductase deficiency and its broader implications. RECENT FINDINGS Since the first report in 2004, at least 21 P450 oxidoreductase mutations have been reported in over 40 patients. The often subtle manifestations of P450 oxidoreductase deficiency suggest it may be relatively common. P450 oxidoreductase deficiency, with or without Antley-Bixler syndrome, is autosomal recessive, whereas Antley-Bixler syndrome without disordered steroidogenesis is caused by autosomal dominant fibroblast growth factor receptor 2 mutations. In-vitro assays of P450 oxidoreductase missense mutations based on P450 oxidoreductase-supported P450c17 activities provide excellent genotype/phenotype correlations. The causal connection between P450 oxidoreductase deficiency and disordered bone formation remains unclear. SUMMARY P450 oxidoreductase mutations cause combined partial deficiency of 17alpha-hydroxylase and 21-hydroxylase. Individuals with an Antley-Bixler syndrome-like phenotype presenting with sexual ambiguity or other abnormalities in steroidogenesis should be analyzed for P450 oxidoreductase deficiency.
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MESH Headings
- Adrenal Hyperplasia, Congenital/complications
- Adrenal Hyperplasia, Congenital/enzymology
- Adrenal Hyperplasia, Congenital/genetics
- Bone Diseases, Developmental/enzymology
- Bone Diseases, Developmental/etiology
- Bone Diseases, Developmental/genetics
- Bone Diseases, Endocrine/enzymology
- Bone Diseases, Endocrine/etiology
- Bone Diseases, Endocrine/genetics
- Bone Diseases, Metabolic/enzymology
- Bone Diseases, Metabolic/etiology
- Bone Diseases, Metabolic/genetics
- Cytochrome P-450 Enzyme System/metabolism
- Genotype
- Humans
- Oxidoreductases/deficiency
- Phenotype
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Affiliation(s)
- Christa E Flück
- Pediatric Endocrinology and Diabetology, University Children's Hospital Bern, Bern, Switzerland
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62
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Duret C, Daujat-Chavanieu M, Pascussi JM, Pichard-Garcia L, Balaguer P, Fabre JM, Vilarem MJ, Maurel P, Gerbal-Chaloin S. Ketoconazole and Miconazole Are Antagonists of the Human Glucocorticoid Receptor: Consequences on the Expression and Function of the Constitutive Androstane Receptor and the Pregnane X Receptor. Mol Pharmacol 2006; 70:329-39. [PMID: 16608920 DOI: 10.1124/mol.105.022046] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The constitutive androstane receptor (CAR) and the pregnane X receptor (PXR) play a major part in the control of drug metabolism and transport. We have previously shown that PXR and CAR expression is controlled by the glucocorticoid receptor (GR) and proposed the existence of a signal transmission cascade GR-(PXR/CAR)-drug metabolizing and transporter systems. In the current study, we investigated the effect of ketoconazole and other azole-derived drugs, miconazole and fluconazole, on the transcriptional activity of the human GR (hGR) in HeLa and HepG2 cells, and in primary human hepatocytes. The data show that ketoconazole inhibits GR transcriptional activity and competes with dexamethasone for hGR binding. In primary human hepatocytes, ketoconazole inhibits the expression of 1) GR-responsive genes tyrosine aminotransferase and both PXR and CAR; 2) CAR and PXR target genes, including cytochromes P450 (P450) CYP2B6, CYP2C9, and CYP3A4; UDP-glucuronosyltransferase 1A1, glutathione S-transferases A1 and A2; and transporter proteins (phase III) solute carrier family 21 form A6 and multidrug resistance protein 2. In parallel experiments, ketoconazole affected neither the expression of GR, the expression of glyceraldehyde-3-phosphate dehydrogenase, nor the inducible expression of CYP1A1 and 1A2. Miconazole behaved like ketoconazole, whereas fluconazole had no effect. We conclude that, in addition to their well known inhibitory effect on P450 enzyme activities, ketoconazole and miconazole are antagonists of hGR. These results provide a novel molecular mechanism by which these compounds may exert adverse and toxic effects on drug metabolism and other functions in human.
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MESH Headings
- Adult
- Aged
- Blotting, Northern
- Blotting, Western
- Cell Line, Tumor
- Cells, Cultured
- Constitutive Androstane Receptor
- Cytochrome P-450 Enzyme System/genetics
- Cytochrome P-450 Enzyme System/metabolism
- Female
- Gene Expression/drug effects
- Glucuronosyltransferase/genetics
- Glucuronosyltransferase/metabolism
- Glutathione Transferase/genetics
- Glutathione Transferase/metabolism
- HeLa Cells
- Hepatocytes/cytology
- Hepatocytes/drug effects
- Hepatocytes/metabolism
- Humans
- Ketoconazole/pharmacology
- Luciferases/genetics
- Luciferases/metabolism
- Male
- Miconazole/pharmacology
- Middle Aged
- Pregnane X Receptor
- Promoter Regions, Genetic/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
- Receptors, Glucocorticoid/antagonists & inhibitors
- Receptors, Glucocorticoid/genetics
- Receptors, Glucocorticoid/metabolism
- Receptors, Steroid/antagonists & inhibitors
- Receptors, Steroid/genetics
- Receptors, Steroid/metabolism
- Transcription Factors/antagonists & inhibitors
- Transcription Factors/genetics
- Transcription Factors/metabolism
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Affiliation(s)
- Cedric Duret
- INSERM U632, Hepatic Physiopathology, 1919 route de Mende, 34293 Montpellier, France
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63
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Wang F, Shen Y, Song X, Xia G, Chen X, Zhou B, Lei L. cDNA Cloning, Genomic Structure and Expression Analysis of the Bovine Lanosterol 14.ALPHA.-Demethylase (CYP51) in Gonads. Biol Pharm Bull 2006; 29:430-6. [PMID: 16508140 DOI: 10.1248/bpb.29.430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Meiosis activating sterol (MAS), the intermediate of cholesterol biosynthesis, is an important substance to stimulate oocytes maturation in FSH-induced signal transduction pathway. Lanosterol 14alpha-demethylase (CYP51) converts lanosterol to MAS. Although MAS is firstly isolated from bovine testis, the information about bovine CYP51 gene and its expression is little. In present studies, the cDNA cloning, genomic structure, chromosomal mapping, and expression patterns of bovine CYP51 were demonstrated. The cDNA coding bovine CYP51 contains a 1509 bp open reading frame and a 1119 bp 3' untranslated region. And the bovine CYP51 gene includes 10 exons and spans about 17 kb. Screening the cattle RH5000 panel bovine CYP51 is mapped to chromosome 4 (0cR). The sequenced promoter region is TATA-less and contains several highly conserved regulatory elements, such as GC-box, cAMP-responsive elements (CRE), sterol regulatory element (SRE) which is important fragment for its transcription. No evidence of processed pseudogenes is found using long PCR and Southern blot. Northern blot analysis reveals that an approximately 2.7 kb mRNA is expressed in all the examined bovine tissues, while a 1.8 kb mRNA is found only in the mature bovine testis where the MAS is accumulated. Immunochemistry analysis shows that leydig cells express the highest level of the CYP51 protein in testis. Among different stages follicles it is localized primarily to the oocytes with the level varying slightly. Granulosa cells of primordial, primary and secondary follicles show background staining. While granulosa cells facing the antrum and cumulus granulosa cells of antral follicles show considerably heavier staining. The highest level is expressed in corpus lutea. These data indicate a stage- and cell type-specific expression of CYP51 protein in bovine oogenesis.
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Affiliation(s)
- Fengchao Wang
- College of Biological Science, China Agricultural University, Beijing, PR China
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64
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Fink M, Acimovic J, Rezen T, Tansek N, Rozman D. Cholesterogenic lanosterol 14alpha-demethylase (CYP51) is an immediate early response gene. Endocrinology 2005; 146:5321-31. [PMID: 16123160 DOI: 10.1210/en.2005-0781] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Lanosterol 14alpha-demethylase (CYP51) responds to cholesterol feedback regulation through sterol regulatory element binding proteins (SREBPs). The proximal promoter of CYP51 contains a conserved region with clustered regulatory elements: GC box, cAMP-response elements (CRE-like), and sterol regulatory element (SRE). In lipid-rich (SREBP-poor) conditions, the CYP51 mRNA drops gradually, the promoter activity is diminished, and no DNA-protein complex is observed at the CYP51-SRE1 site. The majority of cAMP-dependent transactivation is mediated through a single CRE (CYP51-CRE2). Exposure of JEG-3 cells to forskolin, a mediator of the cAMP-dependent signaling pathway, provokes an immediate early response of CYP51, which has not been described before for any cholesterogenic gene. The CYP51 mRNA increases up to 4-fold in 2 h and drops to basal level after 4 h. The inducible cAMP early repressor (ICER) is involved in attenuation of transcription. Overexpressed CRE-binding protein (CREB)/CRE modulator (CREM) transactivates the mouse/human CYP51 promoters containing CYP51-CRE2 independently of SREBPs, and ICER decreases the CREB-induced transcription. Besides the increased CYP51 mRNA, forskolin affects the de novo sterol biosynthesis in JEG-3 cells. An increased consumption of lanosterol, a substrate of CYP51, is observed together with modulation of the postlanosterol cholesterogenesis, indicating that cAMP-dependent stimuli cross-talk with cholesterol feedback regulation. CRE-2 is essential for cAMP-dependent transactivation, whereas SRE seems to be less important. Interestingly, when CREB is not limiting, the increasing amounts of SREBP-1a fail to transactivate the CYP51 promoter above the CREB-only level, suggesting that hormones might have an important role in regulating cholesterogenesis in vivo.
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Affiliation(s)
- Martina Fink
- Medical Center for Molecular Biology, Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Slovenia
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65
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Kumarakulasingham M, Rooney PH, Dundas SR, Telfer C, Melvin WT, Curran S, Murray GI. Cytochrome p450 profile of colorectal cancer: identification of markers of prognosis. Clin Cancer Res 2005; 11:3758-65. [PMID: 15897573 DOI: 10.1158/1078-0432.ccr-04-1848] [Citation(s) in RCA: 136] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE The cytochromes P450 (P450) are a multigene family of enzymes with a central role in the oxidative metabolism of a wide range of xenobiotics, including anticancer drugs, carcinogens, and endogenous compounds. The purpose of this study was to define the P450 profile of colorectal cancer and establish the prognostic significance of expression of individual P450s in colorectal cancer. EXPERIMENTAL DESIGN Immunohistochemistry for a panel of 23 P450s was done on a colorectal cancer tissue microarray consisting of 264 primary colorectal cancers, 91 lymph node metastasis, and 10 normal colorectal samples. The intensity of immunoreactivity in each sample was established by light microscopy. RESULTS The most frequently expressed form of P450 in normal colon was CYP3A4. In primary colorectal cancer, several P450s (CYP1B1, CYP2S1, CYP2U1, CYP3A5, and CYP51) were present at a significantly higher level of intensity compared with normal colon. P450 expression was also detected in lymph node metastasis and the presence of several P450s (CYP1B1, CYP2A/2B, CYP2F1, CYP4V2, and CYP39) in the lymph node metastasis strongly correlated with their presence in corresponding primary tumors. The presence of strong CYP51 (log-rank = 12.11, P = 0.0005) or strong CYP2S1 (log-rank = 6.72, P = 0.0095) immunoreactivity were associated with poor prognosis. CYP51 was also an independent marker of prognosis (P = 0.009). CONCLUSIONS The expression of individual P450s has been established in colorectal cancer. Several P450s show increased expression in colorectal cancer. High expression of CYP51 or CYP2S1 were associated with poor prognosis and CYP51 is an independent marker of prognosis.
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Affiliation(s)
- Meera Kumarakulasingham
- Department of Pathology, University of Aberdeen and Auvation, Ltd., Aberdeen, United Kingdom
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66
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Kim HB, Schaller H, Goh CH, Kwon M, Choe S, An CS, Durst F, Feldmann KA, Feyereisen R. Arabidopsis cyp51 mutant shows postembryonic seedling lethality associated with lack of membrane integrity. PLANT PHYSIOLOGY 2005; 138:2033-47. [PMID: 16040657 PMCID: PMC1183393 DOI: 10.1104/pp.105.061598] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2005] [Revised: 05/10/2005] [Accepted: 05/10/2005] [Indexed: 05/03/2023]
Abstract
CYP51 exists in all organisms that synthesize sterols de novo. Plant CYP51 encodes an obtusifoliol 14alpha-demethylase involved in the postsqualene sterol biosynthetic pathway. According to the current gene annotation, the Arabidopsis (Arabidopsis thaliana) genome contains two putative CYP51 genes, CYP51A1 and CYP51A2. Our studies revealed that CYP51A1 should be considered an expressed pseudogene. To study the functional importance of the CYP51A2 gene in plant growth and development, we isolated T-DNA knockout alleles for CYP51A2. Loss-of-function mutants for CYP51A2 showed multiple defects, such as stunted hypocotyls, short roots, reduced cell elongation, and seedling lethality. In contrast to other sterol mutants, such as fk/hydra2 and hydra1, the cyp51A2 mutant has only minor defects in early embryogenesis. Measurements of endogenous sterol levels in the cyp51A2 mutant revealed that it accumulates obtusifoliol, the substrate of CYP51, and a high proportion of 14alpha-methyl-delta8-sterols, at the expense of campesterol and sitosterol. The cyp51A2 mutants have defects in membrane integrity and hypocotyl elongation. The defect in hypocotyl elongation was not rescued by the exogenous application of brassinolide, although the brassinosteroid-signaling cascade is apparently not affected in the mutants. Developmental defects in the cyp51A2 mutant were completely rescued by the ectopic expression of CYP51A2. Taken together, our results demonstrate that the Arabidopsis CYP51A2 gene encodes a functional obtusifoliol 14alpha-demethylase enzyme and plays an essential role in controlling plant growth and development by a sterol-specific pathway.
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Affiliation(s)
- Ho Bang Kim
- Department of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 151-747, Korea.
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67
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Fukami M, Horikawa R, Nagai T, Tanaka T, Naiki Y, Sato N, Okuyama T, Nakai H, Soneda S, Tachibana K, Matsuo N, Sato S, Homma K, Nishimura G, Hasegawa T, Ogata T. Cytochrome P450 oxidoreductase gene mutations and Antley-Bixler syndrome with abnormal genitalia and/or impaired steroidogenesis: molecular and clinical studies in 10 patients. J Clin Endocrinol Metab 2005; 90:414-26. [PMID: 15483095 DOI: 10.1210/jc.2004-0810] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We report on molecular and clinical findings in 10 Japanese patients (four males and six females) from eight families (two pairs of siblings and six isolated cases) with Antley-Bixler syndrome accompanied by abnormal genitalia and/or impaired steroidogenesis. Direct sequencing was performed for all the 15 exons of cytochrome P450 oxidoreductase gene (POR), showing two missense mutations (R457H and Y578C), a 24-bp deletion mutation resulting in loss of nine amino acids and creation of one amino acid (L612_W620delinsR), a single bp insertion mutation leading to frameshift (I444fsX449), and a silent mutation (G5G). R457H has previously been shown to be a pathologic mutation, and computerized modeling analyses indicated that the 15A>G for G5G could disturb an exonic splicing enhancer motif, and the remaining three mutations should affect protein conformations. Six patients were compound heterozygotes, and three patients were R457H homozygotes; no mutation was identified on one allele of the remaining one patient. Clinical findings included various degrees of skeletal features, such as brachycephaly, radiohumeral synostosis, and digital joint contractures in patients of both sexes, normal-to-poor masculinization during fetal and pubertal periods in male patients, virilization during fetal life and poor pubertal development without worsening of virilization in female patients, and relatively large height gain and delayed bone age from the pubertal period in patients of both sexes, together with maternal virilization during pregnancy. Blood cholesterol was grossly normal, and endocrine studies revealed defective CYP17A1 and CYP21A2 activities. The results suggest that Antley-Bixler syndrome with abnormal genitalia and/or impaired steroidogenesis is caused by POR mutations, and that clinical features are variable and primarily explained by impaired activities of POR-dependent CYP51A1, CYP17A1, CYP21A2, and CYP19A1.
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Affiliation(s)
- Maki Fukami
- Department of Endocrinology and Metabolism, National Research Institute for Child Health and Development, 3-35-31 Taishido, Setagaya, Tokyo 154-8567, Japan
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68
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Matsuura K, Yoshioka S, Tosha T, Hori H, Ishimori K, Kitagawa T, Morishima I, Kagawa N, Waterman MR. Structural diversities of active site in clinical azole-bound forms between sterol 14alpha-demethylases (CYP51s) from human and Mycobacterium tuberculosis. J Biol Chem 2004; 280:9088-96. [PMID: 15611056 DOI: 10.1074/jbc.m413042200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To gain insights into the molecular basis of the design for the selective azole anti-fungals, we compared the binding properties of azole-based inhibitors for cytochrome P450 sterol 14alpha-demethylase (CYP51) from human (HuCYP51) and Mycobacterium tuberculosis (MtCYP51). Spectroscopic titration of azoles to the CYP51s revealed that HuCYP51 has higher affinity for ketoconazole (KET), an azole derivative that has long lipophilic groups, than MtCYP51, but the affinity for fluconazole (FLU), which is a member of the anti-fungal armamentarium, was lower in HuCYP51. The affinity for 4-phenylimidazole (4-PhIm) to MtCYP51 was quite low compared with that to HuCYP51. In the resonance Raman spectra for HuCYP51, the FLU binding induced only minor spectral changes, whereas the prominent high frequency shift of the bending mode of the heme vinyl group was detected in the KET- or 4-PhIm-bound forms. On the other hand, the bending mode of the heme propionate group for the FLU-bound form of MtCYP51 was shifted to high frequency as found for the KET-bound form, but that for 4-PhIm was shifted to low frequency. The EPR spectra for 4-PhIm-bound MtCYP51 and FLU-bound HuCYP51 gave multiple g values, showing heterogeneous binding of the azoles, whereas the single gx and gz values were observed for other azole-bound forms. Together with the alignment of the amino acid sequence, these spectroscopic differences suggest that the region between the B' and C helices, particularly the hydrophobicity of the C helix, in CYP51s plays primary roles in determining strength of interactions with azoles; this differentiates the binding specificity of azoles to CYP51s.
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Affiliation(s)
- Koji Matsuura
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
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69
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Revankar SG, Fu J, Rinaldi MG, Kelly SL, Kelly DE, Lamb DC, Keller SM, Wickes BL. Cloning and characterization of the lanosterol 14alpha-demethylase (ERG11) gene in Cryptococcus neoformans. Biochem Biophys Res Commun 2004; 324:719-28. [PMID: 15474487 DOI: 10.1016/j.bbrc.2004.09.112] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2004] [Indexed: 10/26/2022]
Abstract
The ergosterol pathway in fungal pathogens is an attractive antimicrobial target because it is unique from the major sterol (cholesterol) producing pathway in humans. Lanosterol 14alpha-demethylase is the target for a major class of antifungals, the azoles. In this study we have isolated the gene for this enzyme from Cryptococcus neoformans. The gene, ERG11, was recovered using degenerate PCR with primers designed with a novel algorithm called CODEHOP. Sequence analysis of Erg11p identified a highly conserved region typical of the cytochrome P450 class of mono-oxygenases. The gene was present in single copy in the genome and mapped to one end of the largest chromosome. Comparison of the protein sequence to a number of major human fungal pathogen Erg11p homologs revealed that the C. neoformans protein was highly conserved, and most closely related to the Erg11p homologs from other basidiomycetes. Functional studies demonstrated that the gene could complement a Saccharomyces cerevisiae erg11 mutant, which confirmed the identity of the C. neoformans gene.
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Affiliation(s)
- S G Revankar
- Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, TX 75216, USA
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70
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Kojima M, Masui T, Nemoto K, Degawa M. Lead nitrate-induced development of hypercholesterolemia in rats: sterol-independent gene regulation of hepatic enzymes responsible for cholesterol homeostasis. Toxicol Lett 2004; 154:35-44. [PMID: 15475176 DOI: 10.1016/j.toxlet.2004.06.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2004] [Revised: 06/30/2004] [Accepted: 06/30/2004] [Indexed: 11/24/2022]
Abstract
Changes in the gene expressions of hepatic enzymes responsible for cholesterol homeostasis were examined during the process of lead nitrate (LN)-induced development of hypercholesterolemia in male rats. Total cholesterol levels in the liver and serum were significantly increased at 3-72 h and 12-72 h, respectively, after LN-treatment (100 micromol/kg, i.v.). Despite the development of hypercholesterolemia, the genes for hepatic 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) and other enzymes (FPPS, farnesyl diphosphate synthase; SQS, squalene synthase; CYP51, lanosterol 14alpha-demethylase) responsible for cholesterol biosynthesis were activated at 3-24 h and 12-18 h, respectively. On the other hand, the gene expression of cholesterol 7alpha-hydroxylase (CYP7A1), a catabolic enzyme of cholesterol, was remarkably suppressed at 3-72 h. The gene expression levels of cytokines interleukin-1beta (IL-1beta) and TNF-alpha, which activate the HMGR gene and suppress the CYP7A1 gene, were significantly increased at 1-3 h and 3-24 h, respectively. Furthermore, gene activation of SREBP-2, a gene activator of several cholesterogenic enzymes, occurred before the gene activations of FPPS, SQS and CYP51. This is the first report demonstrating sterol-independent gene regulation of hepatic enzymes responsible for cholesterol homeostasis in LN-treated male rats. The mechanisms for the altered-gene expressions of hepatic enzymes in LN-treated rats are discussed.
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Affiliation(s)
- Misaki Kojima
- Laboratory of Animal Gene Function, Department of Physiology and Gene Regulation, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba 305-8602, Japan
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71
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Rezen T, Debeljak N, Kordis D, Rozman D. New Aspects on Lanosterol 14α-Demethylase and Cytochrome P450 Evolution: Lanosterol/Cycloartenol Diversification and Lateral Transfer. J Mol Evol 2004; 59:51-8. [PMID: 15383907 DOI: 10.1007/s00239-004-2603-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2003] [Accepted: 01/12/2004] [Indexed: 11/30/2022]
Abstract
Sterol 14alpha-demethylase (CYP51) is a member of the cytochrome P450 superfamily, widely found in animals, fungi, and plants but present in few prokaryotic groups. CYP51 is currently believed to be the ancestral cytochrome P450 that has been transferred from prokaryotes to eukaryotic kingdoms. We propose an alternate view of CYP51 evolution that has an impact on understanding the evolution of the entire CYP superfamily. Two hundred forty-nine bacterial and four archaeal CYP sequences have been aligned and a bacterial CYP tree designed, showing a separation of two branches. Prokaryotic CYP51s cluster to the minor branch, together with other eukaryote-like CYPs. Mycobacterial and methylococcal CYP51s cluster together (100% bootstrap probability), while Streptomyces CYP51 remains on a distant branch. A CYP51 phylogenetic tree has been constructed from 44 sequences resulting in a ((plant, bacteria),(animal, fungi)) topology (100% bootstrap probability). This is in accordance with the lanosterol/cycloartenol diversification of sterol biosynthesis. The lanosterol branch (nonphotosynthetic lineage) follows the previously proposed topology of animal and fungal orthologues (100% bootstrap probability), while plant and D. discoideum CYP51s belong to the cycloartenol branch (photosynthetic lineage), all in accordance with biochemical data. Bacterial CYP51s cluster within the cycloartenol branch (69% bootstrap probability), which is indicative of a lateral gene transfer of a plant CYP51 to the methylococcal/mycobacterial progenitor, suggesting further that bacterial CYP51s are not the oldest CYP genes. Lateral gene transfer is likely far more important than hitherto thought in the development of the diversified CYP superfamily. Consequently, bacterial CYPs may represent a mixture of genes with prokaryotic and eukaryotic origin.
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Affiliation(s)
- Tadeja Rezen
- Institute of Biochemistry, Medical Center for Molecular Biology, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, SI-1000, Ljubljana, Slovenia
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72
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Nelson DR, Schuler MA, Paquette SM, Werck-Reichhart D, Bak S. Comparative genomics of rice and Arabidopsis. Analysis of 727 cytochrome P450 genes and pseudogenes from a monocot and a dicot. PLANT PHYSIOLOGY 2004; 135:756-72. [PMID: 15208422 PMCID: PMC514113 DOI: 10.1104/pp.104.039826] [Citation(s) in RCA: 291] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2004] [Revised: 03/31/2004] [Accepted: 03/31/2004] [Indexed: 05/18/2023]
Abstract
Data mining methods have been used to identify 356 Cyt P450 genes and 99 related pseudogenes in the rice (Oryza sativa) genome using sequence information available from both the indica and japonica strains. Because neither of these genomes is completely available, some genes have been identified in only one strain, and 28 genes remain incomplete. Comparison of these rice genes with the 246 P450 genes and 26 pseudogenes in the Arabidopsis genome has indicated that most of the known plant P450 families existed before the monocot-dicot divergence that occurred approximately 200 million years ago. Comparative analysis of P450s in the Pinus expressed sequence tag collections has identified P450 families that predated the separation of gymnosperms and flowering plants. Complete mapping of all available plant P450s onto the Deep Green consensus plant phylogeny highlights certain lineage-specific families maintained (CYP80 in Ranunculales) and lineage-specific families lost (CYP92 in Arabidopsis) in the course of evolution.
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Affiliation(s)
- David R Nelson
- Department of Molecular Sciences and Center of Excellence in Genomics and Bioinformatics, University of Tennessee, Memphis, Tennessee 38163, USA.
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Oishi K, Miyazaki K, Kadota K, Kikuno R, Nagase T, Atsumi GI, Ohkura N, Azama T, Mesaki M, Yukimasa S, Kobayashi H, Iitaka C, Umehara T, Horikoshi M, Kudo T, Shimizu Y, Yano M, Monden M, Machida K, Matsuda J, Horie S, Todo T, Ishida N. Genome-wide expression analysis of mouse liver reveals CLOCK-regulated circadian output genes. J Biol Chem 2003; 278:41519-27. [PMID: 12865428 DOI: 10.1074/jbc.m304564200] [Citation(s) in RCA: 271] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
CLOCK is a positive component of a transcription/translation-based negative feedback loop of the central circadian oscillator in the suprachiasmatic nucleus in mammals. To examine CLOCK-regulated circadian transcription in peripheral tissues, we performed microarray analyses using liver RNA isolated from Clock mutant mice. We also compared expression profiles with those of Cryptochromes (Cry1 and Cry2) double knockout mice. We identified more than 100 genes that fluctuated from day to night and of which expression levels were decreased in Clock mutant mice. In Cry-deficient mice, the expression levels of most CLOCK-regulated genes were elevated to the upper range of normal oscillation. Most of the screened genes had a CLOCK/BMAL1 binding site (E box) in the 5'-flanking region. We found that CLOCK was absolutely concerned with the circadian transcription of one type of liver genes (such as DBP, TEF, and Usp2) and partially with another (such as mPer1, mPer2, mDec1, Nocturnin, P450 oxidoreductase, and FKBP51) because the latter were damped but remained rhythmic in the mutant mice. Our results showed that CLOCK and CRY proteins are involved in the transcriptional regulation of many circadian output genes in the mouse liver. In addition to being a core component of the negative feedback loop that drives the circadian oscillator, CLOCK also appears to be involved in various physiological functions such as cell cycle, lipid metabolism, immune functions, and proteolysis in peripheral tissues.
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Affiliation(s)
- Katsutaka Oishi
- Clock Cell Biology Research Group, Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology, Central 6, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan
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