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Chen M, Wang N, Yang H, Liu D, Gao Y, Duo L, Cui X, Hao F, Ye J, Gao F, Tu Q, Gui Y. Single-cell transcriptome analysis of the germ cells and somatic cells during mitotic quiescence stage in goats. FASEB J 2023; 37:e23244. [PMID: 37823602 DOI: 10.1096/fj.202301278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 09/25/2023] [Indexed: 10/13/2023]
Abstract
The mitotic quiescence of prospermatogonia is the event known to occur during genesis of the male germline and is tied to the development of the spermatogenic lineage. The regulatory mechanisms and the functional importance of this process have been demonstrated in mice; however, regulation of this process in human and domestic animal is still largely unknown. In this study, we employed single-cell RNA sequencing to identify transcriptional signatures of prospermatogonia and major somatic cell types in testes of goats at E85, E105, and E125. We identified both common and specific Gene Ontology categories, transcription factor regulatory networks, and cell-cell interactions in cell types from goat testis. We also analyzed the transcriptional dynamic changes in prospermatogonia, Sertoli cells, Leydig cells, and interstitial cells. Our datasets provide a useful resource for the study of domestic animal germline development.
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Affiliation(s)
- Min Chen
- Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Institute of Urology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, China
| | - Nan Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hang Yang
- University of Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Dongjun Liu
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, Inner Mongolia University, Hohhot, China
| | - Yuan Gao
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, Inner Mongolia University, Hohhot, China
| | - Lei Duo
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, Inner Mongolia University, Hohhot, China
| | - Xiuhong Cui
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
| | - Fei Hao
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, Inner Mongolia University, Hohhot, China
| | - Jing Ye
- Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Institute of Urology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, China
| | - Fei Gao
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qiang Tu
- University of Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Yaoting Gui
- Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Institute of Urology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, China
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Dumontet T, Martinez A. Adrenal androgens, adrenarche, and zona reticularis: A human affair? Mol Cell Endocrinol 2021; 528:111239. [PMID: 33676986 DOI: 10.1016/j.mce.2021.111239] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/11/2021] [Accepted: 03/01/2021] [Indexed: 12/11/2022]
Abstract
In humans, reticularis cells of the adrenal cortex fuel the production of androgen steroids, constituting the driver of numerous morphological changes during childhood. These steps are considered a precocious stage of sexual maturation and are grouped under the term "adrenarche". This review describes the molecular and enzymatic characteristics of the zona reticularis, along with the possible signals and mechanisms that control its emergence and the associated clinical features. We investigate the differences between species and discuss new studies such as genetic lineage tracing and transcriptomic analysis, highlighting the rodent inner cortex's cellular and molecular heterogeneity. The recent development and characterization of mouse models deficient for Prkar1a presenting with adrenocortical reticularis-like features prompt us to review our vision of the mouse adrenal gland maturation. We expect these new insights will help increase our understanding of the adrenarche process and the pathologies associated with its deregulation.
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Affiliation(s)
- Typhanie Dumontet
- Department of Internal Medicine, Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, MI, USA; Training Program in Organogenesis, Center for Cell Plasticity and Organ Design, University of Michigan, Ann Arbor, MI, USA.
| | - Antoine Martinez
- Génétique, Reproduction et Développement (GReD), Centre National de La Recherche Scientifique CNRS, Institut National de La Santé & de La Recherche Médicale (INSERM), Université Clermont-Auvergne (UCA), France.
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3
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Ge RS, Li X, Wang Y. Leydig Cell and Spermatogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1288:111-129. [PMID: 34453734 DOI: 10.1007/978-3-030-77779-1_6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Leydig cells of the testis have the capacity to synthesize androgen (mainly testosterone) from cholesterol. Adult Leydig cells are the cell type for the synthesis of testosterone, which is critical for spermatogenesis. At least four steroidogenic enzymes take part in testosterone synthesis: cytochrome P450 cholesterol side chain cleavage enzyme, 3β-hydroxysteroid dehydrogenase, cytochrome P450 17α-hydroxylase/17,20-lyase and 17β-hydroxysteroid dehydrogenase isoform 3. Testosterone metabolic enzyme steroid 5α-reductase 1 and 3α-hydroxysteroid dehydrogenase are expressed in some precursor Leydig cells. Androgen is transported by androgen-binding protein to Sertoli cells, where it binds to androgen receptor to regulate spermatogenesis.
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Affiliation(s)
- Ren-Shan Ge
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.
| | - Xiaoheng Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China
| | - Yiyan Wang
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China
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Mu W, Wen H, He F, Li J, Liu M, Ma R, Zhang Y, Hu J, Qi B. Cloning and expression analysis of the cytochrome P450c17s enzymes during the reproductive cycle in ovoviviparous Korean rockfish (Sebastes schlegeli). Gene 2013; 512:444-9. [DOI: 10.1016/j.gene.2012.10.064] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Revised: 09/13/2012] [Accepted: 10/10/2012] [Indexed: 10/27/2022]
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5
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Storbeck KH, Swart AC, Swart P. CYP17 causes hypocortisolism in the South African Angora goat. Mol Cell Endocrinol 2009; 300:121-5. [PMID: 18840497 DOI: 10.1016/j.mce.2008.09.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 09/01/2008] [Accepted: 09/05/2008] [Indexed: 11/17/2022]
Abstract
Two cytochrome P450 17alpha-hydroxylase/17,20-lyase (CYP17) isoforms have been identified in the South African Angora goat (Capra hircus) and have been implicated as the primary cause of hypocortisolism in this subspecies. These goats are the most efficient fibre producing, but least hardy, small stock breed in Southern Africa. Their inability to cope with prolonged exposure to cold and the resulting stock loss which occurs during winter have been the subject of numerous studies. The two isoforms are encoded for by two separate genes, a novel finding for a mammalian species. The enzymes have unique catalytic properties and differ with respect to their 17,20-lyase activities towards 17-hydroxypregnenolone and subsequent androgen production. In vivo assays confirmed that the three resulting genotypes differed in their ability to produce cortisol in response to intravenous insulin injection implicating CYP17 as the primary cause of the observed hypocortisolism.
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Affiliation(s)
- Karl-Heinz Storbeck
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7602, South Africa
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6
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Shet MS, Fisher CW, Tremblay Y, Belanger A, Conley AJ, Mason JI, Estabrook RW. Comparison of the 17α-Hydroxylase/C17,20-Lyase Activities of Porcine, Guinea Pig and Bovine P450c17 Using Purified Recombinant Fusion Proteins Containing P450c17 Linked to NADPH-P450 Reductase. Drug Metab Rev 2008; 39:289-307. [PMID: 17786622 DOI: 10.1080/03602530701468391] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The cDNAs for cytochrome P450c17 (P450c17) of three species, pig, guinea pig, and cow, representing three families of mammals (suidae, procaviidae, and bovidae, respectively) were each engineered into an expression plasmid (pCWori+). The P450c17 domain of the coding sequence was connected to a truncated form of rat NADPH-P450 reductase by a linker sequence encoding two amino acids (SerThr). These fusion proteins were expressed in E. coli and purified for use in enzymatic assays to determine similarities and differences in 17 alpha-hydroxylase and lyase activities. The fusion proteins were found to catalyze both the 17 alpha-hydroxylation of progesterone (P4) and pregnenolone (P5) to 17 alpha-hydroxylated P4 and P5 (17 alpha-OH P4 and 17 alpha-OH P5) followed by the C17,20-lyase reaction for the conversion of these C(21)-17 alpha-hydroxylated steroids to C(19)-steroids (the C17,20-lyase reaction). These in vitro studies show that (a) porcine P450c17 possesses cytochrome b(5) (b(5))-stimulated C17,20-lyase activity that converts 17 alpha OH-P4 to androstenedione (AD) but also converts 17 alpha-OHP5 to dehydroepiandrosterone (DHEA); (b) guinea pig P450c17 possesses a b(5)-stimulated C17,20-lyase activity that converts 17 alpha-OH P4 to AD but does not convert 17 alpha-OH P5 to DHEA., and (c) bovine P450c17 possesses a b(5)-stimulated C17,20-lyase activity that converts 17 alpha-OH P5 to DHEA but does not convert 17 alpha-OH P4 to AD. Thus, the P450c17 of each species differs in its ability to catalyze in vitro the conversion of C(21)-steroids to C(19)-steroids. In addition, each P450c17 is capable of catalyzing additional hydroxylation reactions leading to low levels of 2 alpha-, 6 beta-, 16- and 21-hydroxy-metabolites. Porcine P450c17 also catalyzes the b(5)-dependent synthesis of andien-beta (androsta-5,16-dien-3beta-ol) from P5. When the amino acid sequences of the three P450c17s were aligned there was an approximate 50% variation in the alignment identity (227 differences in the sequences of 509 amino acids). Alignment did not permit the assignment of specific amino acids or domains to the observed differences in enzymatic activities.
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Affiliation(s)
- Manjunath S Shet
- Purdue Pharma LP, Department of Pharmocokinetics and Drug Metabolism, Stamford, Connecticut, USA
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7
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Storbeck KH, Swart AC, Snyman MA, Swart P. Two CYP17 genes in the South African Angora goat (Capra hircus) - the identification of three genotypes that differ in copy number and steroidogenic output. FEBS J 2008; 275:3934-43. [PMID: 18616460 DOI: 10.1111/j.1742-4658.2008.06539.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In mammals, cytochrome P450 17alpha-hydroxylase/17-20 lyase (CYP17), which is encoded by a single gene, plays a critical role in the production of mineralocorticoids, glucocorticoids and androgens by the adrenal cortex. Two CYP17 isoforms with unique catalytic properties have been identified in the South African Angora goat (Capra hircus), a subspecies that is susceptible to cold stress because of the inability of the adrenal cortex to produce sufficient levels of cortisol. A real-time-based genotyping assay was used in this study to identify the distribution of the two CYP17 alleles in the South African Angora population. These data revealed that the two CYP17 isoforms were not the product of two alleles of the same gene, but two separate CYP17 genes encoding the two unique CYP17 isoforms. This novel finding was subsequently confirmed by quantitative real-time PCR. Goats were divided into three unique genotypes which differed not only in the genes encoding CYP17, but also in copy number. Furthermore, in vivo assays revealed that the identified genotypes differed in their ability to produce cortisol in response to intravenous insulin injection. This study clearly demonstrates the presence of two CYP17 genes in the South African Angora goat, and further implicates CYP17 as the primary cause of the observed hypocortisolism in this subspecies.
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8
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Takamiya M, Lambard S, Huhtaniemi IT. Effect of bisphenol A on human chorionic gonadotrophin-stimulated gene expression of cultured mouse Leydig tumour cells. Reprod Toxicol 2007; 24:265-75. [PMID: 17706920 DOI: 10.1016/j.reprotox.2007.07.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Revised: 06/27/2007] [Accepted: 07/02/2007] [Indexed: 12/20/2022]
Abstract
Endocrine disrupting chemicals (EDCs) have been reported to affect the reproductive system of various animal species. However, their specific effects and modes of action on gonadal function remain largely unclear. We studied the effects of a model EDC, bisphenol A (BPA), on human chorionic gonadotrophin (hCG)-stimulated global gene expression of cultured mouse Leydig tumour cells (mLTC-1). The time and dose of BPA exposure were set after semiquantitative (sq) RT-PCR analysis of response of candidate genes (StAR, Cyp 17 a1 and AR) to 3h at 10 microg/l hCG +/- 10(-5)M BPA. Affymetrix microarray analysis demonstrated > or =1.5-fold up-regulation of 8- and < or =1.5-fold down-regulated of 16 genes by BPA. Several of these genes were related to steroid/cholesterol metabolism/transport and cell cycle regulation. sqRT-PCR demonstrated induction of StAR expression by hCG stimulation and no effect of BPA. In conclusion, our results indicate that BPA has only subtle modulating effects on gene expression of gonadotrophin-stimulated mLTC-1 cells.
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Affiliation(s)
- Minako Takamiya
- Cranfield Health, Cranfield University, Barton Road, Silsoe, Bedfordshire MK45 4DT, UK.
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9
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Ingman WV, Robker RL, Woittiez K, Robertson SA. Null mutation in transforming growth factor beta1 disrupts ovarian function and causes oocyte incompetence and early embryo arrest. Endocrinology 2006; 147:835-45. [PMID: 16269452 DOI: 10.1210/en.2005-1189] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
TGFbeta1 is implicated in regulation of ovarian function and the events of early pregnancy. We have investigated the effect of null mutation in the Tgfbeta1 gene on reproductive function in female mice. The reproductive capacity of TGFbeta1 null mutant females was severely impaired, leading to almost complete infertility. Onset of sexual maturity was delayed, after which ovarian function was disrupted, with extended ovarian cycles, irregular ovulation, and a 40% reduction in oocytes ovulated. Serum FSH and estrogen content were normal, but TGFbeta1 null mutant mice failed to display the characteristic proestrus surge in circulating LH. Ovarian hyperstimulation with exogenous gonadotropins elicited normal ovulation rates in TGFbeta1 null mutant mice. After mating with wild-type stud males, serum progesterone content was reduced by 75% associated with altered ovarian expression of mRNAs encoding steroidogenic enzymes 3beta-hydroxysteroid dehydrogenase-1 and P450 17 alpha-hydroxylase/C17-20-lyase. Embryos recovered from TGFbeta1 null mutant females were developmentally arrested in the morula stage and rarely progressed to blastocysts. Attempts to rescue embryos by exogenous progesterone administration and in vitro culture were unsuccessful, and in vitro fertilization and culture experiments demonstrated that impaired development is unlikely to result from lack of maternal tract TGFbeta1. We conclude that embryo arrest is due to developmental incompetence in oocytes developed in a TGFbeta1-deficient follicular environment. This study demonstrates that TGFbeta1 is a critical determinant of normal ovarian function, operating through regulation of LH activity and generation of oocytes competent for embryonic development and successful initiation of pregnancy.
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Affiliation(s)
- Wendy V Ingman
- Research Centre for Reproductive Health, Department of Obstetrics and Gynaecology, University of Adelaide, South Australia
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10
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Liu Y, Yao ZX, Bendavid C, Borgmeyer C, Han Z, Cavalli LR, Chan WY, Folmer J, Zirkin BR, Haddad BR, Gallicano GI, Papadopoulos V. Haploinsufficiency of cytochrome P450 17alpha-hydroxylase/17,20 lyase (CYP17) causes infertility in male mice. Mol Endocrinol 2005; 19:2380-9. [PMID: 15890676 DOI: 10.1210/me.2004-0418] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Cytochrome P450 17alpha-hydroxylase/17,20-lyase (CYP17) is critical in determining cortisol and sex steroid biosynthesis. To investigate how CYP17 functions in vivo, we generated mice with a targeted deletion of CYP17. Although in chimeric mice Leydig cell CYP17 mRNA and intratesticular and circulating testosterone levels were dramatically reduced (80%), the remaining testosterone was sufficient to support spermatogenesis as evidenced by the generation of phenotypical black C57BL/6 mice. However, male chimeras consistently failed to generate heterozygous CYP17 mice and after five matings chimeric mice stopped mating indicating a change in sexual behavior. These results suggested that CYP17 deletion caused a primary phenotype (infertility), probably not due to the anticipated androgen imbalance and a secondary phenotype (change in sexual behavior) due to the androgen imbalance. Surprisingly, CYP17 mRNA was found in mature sperm, and serial analysis of gene expression identified CYP17 mRNA in other testicular germ cells. CYP17 mRNA levels were directly related to percent chimerism. Moreover, more than 50% of the sperm from high-percentage chimeric mice were morphologically abnormal, and half of them failed the swim test. Furthermore, 60% of swimming abnormal sperm was devoid of CYP17. These results suggest that CYP17, in addition to its role in steroidogenesis and androgen formation, is present in germ cells where it is essential for sperm function, and deletion of one allele prevents genetic transmission of mutant and wild-type alleles causing infertility followed by change in sexual behavior due to androgen imbalance.
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Affiliation(s)
- Ying Liu
- Department of Biochemistry and Molecular Biology, Georgetown University Medical Center, Washington, DC 20057, USA
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11
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Abstract
Significant advances have taken place in our knowledge of the enzymes involved in steroid hormone biosynthesis since the last comprehensive review in 1988. Major developments include the cloning, identification, and characterization of multiple isoforms of 3beta-hydroxysteroid dehydrogenase, which play a critical role in the biosynthesis of all steroid hormones and 17beta-hydroxysteroid dehydrogenase where specific isoforms are essential for the final step in active steroid hormone biosynthesis. Advances have taken place in our understanding of the unique manner that determines tissue-specific expression of P450aromatase through the utilization of alternative promoters. In recent years, evidence has been obtained for the expression of steroidogenic enzymes in the nervous system and in cardiac tissue, indicating that these tissues may be involved in the biosynthesis of steroid hormones acting in an autocrine or paracrine manner. This review presents a detailed description of the enzymes involved in the biosynthesis of active steroid hormones, with emphasis on the human and mouse enzymes and their expression in gonads, adrenal glands, and placenta.
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Affiliation(s)
- Anita H Payne
- Division of Reproductive Biology, Department of Obstetrics and Gynecology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, California 94305-5317, USA.
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London SE, Boulter J, Schlinger BA. Cloning of the zebra finch androgen synthetic enzyme CYP17: a study of its neural expression throughout posthatch development. J Comp Neurol 2004; 467:496-508. [PMID: 14624484 DOI: 10.1002/cne.10936] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Male zebra finches develop a robust neural song system that supports singing, but females have a minimal song circuit and do not sing. Estrogens masculinize the song circuit and are especially potent during the first 3 weeks of posthatch development. The gonads do not seem to supply the masculinizing steroids, implying that another tissue synthesizes steroids. Evidence suggests that the brain is capable of synthesizing neurosteroids, which in developing zebra finches may be required for song system differentiation. Aromatase, the enzyme that synthesizes estrogen from androgen, is equally abundant in male and female brains. To investigate further the potential for neurosteroidogenesis in the zebra finch brain, we cloned and examined the expression of 17alpha-hydroxylase/17,20 lyase (CYP17), the enzyme that synthesizes the androgenic substrate for aromatase. We used Northern blots, reverse transcription-polymerase chain reaction, and in situ hybridization to show that CYP17 is transcribed in developing and adult brains. CYP17 is transcribed at developmental stages and in brain areas potentially important to aspects of the developing song system, although no sex difference was detected in mRNA levels. Our results support the hypothesis that neurosteroids may act to influence brain organization and function in the zebra finch.
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Affiliation(s)
- Sarah E London
- Interdepartmental Graduate Program in Neuroscience, University of California--Los Angeles, Los Angeles, California 90095, USA.
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13
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Bielinska M, Parviainen H, Porter-Tinge SB, Kiiveri S, Genova E, Rahman N, Huhtaniemi IT, Muglia LJ, Heikinheimo M, Wilson DB. Mouse strain susceptibility to gonadectomy-induced adrenocortical tumor formation correlates with the expression of GATA-4 and luteinizing hormone receptor. Endocrinology 2003; 144:4123-33. [PMID: 12933687 DOI: 10.1210/en.2003-0126] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Certain inbred strains of mice, including DBA/2J, develop adrenocortical tumors in response to gonadectomy. Spindle-shaped cells with limited steroidogenic capacity, termed A cells, appear in the subcapsular region of the adrenal gland, followed by sex steroid-producing cells known as B cells. These changes result from unopposed gonadotropin production by the pituitary, but the adrenocortical factors involved in tumorigenesis have not been characterized. GATA-4, a transcription factor normally expressed in fetal, but not adult, adrenocortical cells, was found in neoplastic cells that proliferate in the adrenal cortex of gonadectomized DBA/2J mice. GATA-4 mRNA was detected in the adrenal glands of female mice 0.5 months after ovariectomy and reached a maximum by 4 months. Castrated male mice developed adrenocortical tumors more slowly than gonadectomized females, and the onset of GATA-4 expression in the adrenal was delayed. In situ hybridization and immunohistochemistry revealed GATA-4 mRNA and protein in A and B cells, but not in normal adrenocortical cells. mRNA encoding another factor associated with adrenocortical tumorigenesis, LH receptor (LHR), was detected in A and B cells. In addition, transcripts for P450 17 alpha-hydroxylase/C17-C20 lyase, an enzyme essential for the production of sex steroids, and inhibin-alpha were found in B cells. Unilateral ovarian regeneration, a phenomenon known to occur in gonadectomized mice, was observed in a subset of DBA/2J mice undergoing complete ovariectomy. In these animals, adrenocortical tumor progression was arrested; A cells and GATA-4 expression were evident, but there was no expression of LHR or P450 17 alpha-hydroxylase/C17-C20 lyase. Strain susceptibility to adrenocortical tumorigenesis (DBA/2J >> FVB/N) correlated with the expression of GATA-4 and LHR, implicating these factors in the process of adrenocortical neoplasia in response to continuous gonadotropin stimulation.
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Affiliation(s)
- Malgorzata Bielinska
- Department of Pediatrics, Washington University School of Medicine, St. Louis Children's Hospital, St. Louis, Missouri 63110, USA
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Mathieu AP, LeHoux JG, Auchus RJ. Molecular dynamics of substrate complexes with hamster cytochrome P450c17 (CYP17): mechanistic approach to understanding substrate binding and activities. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1619:291-300. [PMID: 12573489 DOI: 10.1016/s0304-4165(02)00488-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The cytochrome P450c17 isoforms from various animal species have different substrate selectivity, especially for 17,20-lyase activity. In particular, the human P450c17 selectively produces dehydroepiandrosterone with little androstenedione (AD). Hamster P450c17, on the other hand, produces both of these steroids at comparable rates. We thus investigated if computational analysis could explain the difference in activity profiles. Therefore, we inserted the four P450c17 substrates-pregnenolone, progesterone, and their 17alpha-hydroxylated forms-inside our hamster P450c17 model, which we derived from our human P450c17 model based on the crystal structure of P450BMP. We performed molecular dynamics (MD) simulations on the complexes and analyzed the resultant trajectories to identify amino acids that interact with substrates. Starting with substrates in two different orientations, we obtained two sets of binding trajectories in each case. The first set of trajectories reveal structural rearrangements that occur during binding, whereas the second set of trajectories reflects substrate orientations during catalysis. Our modeling suggests that three distinct steps are required for substrate selectivity and binding to the hamster P450c17: (1) recognition of the substrate at the putative substrate entrance, characterized by a pocket at the surface of the hamster P450c17 containing charged residues R96 and D116; (2) entry of the substrate into the active site, in an intermediate position directed by possible hydrogen bonding of the substrates with the heme D-ring propionate group, R96, R440, and T306; followed by (3) 90 degrees counterclockwise rotation of the substrates, positioning them in optimal position for reactivity, a process that may be directed by hydrogen bonding to the 110-112 region of the hamster P450c17. With some substrates, we obtained trajectories which suggest that major distortions in the I-helix and opening of the H-I loop occur during substrate binding. In conclusion, these modeling exercises provide insight to possible structural reorganizations that occur during substrate binding and suggest that amino acids that participate in three distinct steps of this process may all contribute to substrate binding and activity.
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Affiliation(s)
- Axel P Mathieu
- Department of Biochemistry, Faculty of Medicine, University of Sherbrooke, QC, J1H 5N4, Sherbrooke, Canada
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15
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Schwartz JR, Roy SK. Developmental expression of cytochrome P450 side-chain cleavage and cytochrome P450 17 alpha-hydroxylase messenger ribonucleic acid and protein in the neonatal hamster ovary. Biol Reprod 2000; 63:1586-93. [PMID: 11090424 DOI: 10.1095/biolreprod63.6.1586] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The temporal and spatial expression of cytochrome P450 side-chain cleavage (CYP11A1) and cytochrome P450 17 alpha-hydroxylase (CYP17) mRNA and protein during thecal cell differentiation in developing hamster ovaries were evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence histochemistry, respectively. Ovaries were collected from 15-day fetal through 20-day-old postnatal hamsters and used either for immunofluorescence detection of enzyme protein or RT-PCR evaluation of enzyme mRNA. Immunoreactivity of CYP11A1 first appeared in the interstitial cells on Day 10 postnatal (PN), and the intensity increased significantly with further ovarian development beyond 11 days of age. In contrast, CYP17 immunostaining was first detected in a few interstitial cells closer to large preantral follicles by Day 12 PN, and their number increased appreciably by Day 14 PN. By age 18-20 days, CYP17-positive cells were localized primarily in the thecal layer of large preantral follicles. A low level of CYP17 and CYP11A1 mRNA was present in fetal ovaries. The CYP17 mRNA levels increased sharply by Day 1 PN but decreased to a low baseline level by Day 2 PN and remained low up to Day 9 PN. Both CYP11A1 and CYP17 mRNA levels increased significantly by Day 10 PN compared to Day 9 PN; however, the increase for CYP11A1 was greater than CYP17. The CYP11A1 mRNA levels decreased noticeably on Day 11 PN and remained relatively stable until Day 14 PN; however, mRNA levels started increasing by Day 15 PN and increased sharply by Day 17 PN onward, corresponding to the increase in CYP11A1 protein in the ovarian interstitium and thecal compartments. On the other hand, CYP17 mRNA expression increased progressively through Day 12 PN. A sharp increase in CYP17 mRNA was noted on Day 13 PN in conjunction with the morphological development of thecal cells; mRNA levels remained steady afterward. The correlation of the increase in enzyme mRNA and protein, especially of CYP17, with the morphological development of thecal layers suggests that the differentiation of interstitial cells into theca may be modulated by multilayered preantral follicles, and the expression of enzyme protein occurs prior to an increase in serum LH.
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Affiliation(s)
- J R Schwartz
- Department of Obstetrics and Gynecology, University of Nebraska Medical Center, Omaha, Nebraska 68198-4515, USA
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Schwartz JR, Roy SK. Expression of P450 side-chain cleavage (CYP11A1) and P450 17alpha-hydroxylase-17/20 lyase (CYP17) messenger ribonucleic acid in hamster primary interstitial cells in vitro: differential regulation of steroidogenesis by cyclic adenosine monophosphate. Biol Reprod 2000; 63:503-7. [PMID: 10906056 DOI: 10.1095/biolreprod63.2.503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Interstitial cells in the neonatal hamster do not respond to LH in vitro; however, side-chain cleavage (CYP11A1) and 17alpha-hydroxylase (CYP17) enzyme proteins are expressed in these cells. The objective of the study was to evaluate whether the cAMP second messenger system was active in these cells and if cAMP upregulates the levels of CYP11A1 and CYP17 mRNA. Interstitial cells (ICs) were cultured for 96 h in the presence of 5% fetal bovine serum and then cultured in serum-free medium in the presence of LH, forskolin, or 8-Br-cAMP for 24 h. The accumulation of cAMP, progesterone, and androstenedione was measured by radioimmunoassay, whereas CYP11A1 and CYP17 mRNA levels were determined by a semiquantitative reverse transcription-polymerase chain reaction and Southern hybridization analysis. LH failed to induce either progesterone or androstenedione production; however, forskolin stimulated cAMP production by interstitial cells in a dose-dependent manner. Moreover, both forskolin and 8-Br-cAMP significantly elevated the levels of CYP11A1 and CYP17 mRNA and induced progesterone synthesis by the interstitial cell monolayer. Despite the increase in CYP17 mRNA levels by 8-Br-cAMP, no appreciable change was noted in androstenedione production. These results suggest that, in vitro, a fully functional adenylate cyclase system is present in cultured interstitial cells of the neonatal hamster and that cAMP can influence the expression of CYP11A1 and CYP17 genes; however, cultured cells do not appear to express LH receptors that are functionally linked to the adenylate cyclase system. Moreover, the translation of CYP17 mRNA may require additional factors, which may originate from maturing granulosa cells.
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Affiliation(s)
- J R Schwartz
- Leland J. and Dorothy H. Olson Center for Women's Health, Omaha, Nebraska 68198-4515, USA
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Datta M, Nagendra Prasad RJ, Bhattacharya S. Thyroid hormone regulation of perch ovarian 3beta-hydroxysteroid dehydrogenase/delta5-delta4-isomerase activity: involvement of a 52-kDa protein. Gen Comp Endocrinol 1999; 113:212-20. [PMID: 10082623 DOI: 10.1006/gcen.1998.7175] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ovarian follicles were collected from perch belonging to the prespawning (vitellogenic) stage and incubated in vitro for 5 h in the absence (control) and presence of 3, 5, 3'-triiodothyronine (T3). Addition of increasing concentrations of T3 from 12.5 to 100 ng/ml caused a linear increase of 3beta-hydroxysteroid dehydrogenase/delta5-delta4-isomerase (3 beta-HSD) activity to 50 ng and then it leveled off indicating a saturation of enzyme activity with 50 ng T3. T3 stimulation of 3beta-HSD activity could be blocked by cycloheximide indicating the involvement of T3-induced protein (TIP) isolated and purified earlier from this laboratory. Addition of fish TIP purified from perch ovarian follicle (fTIP) or rat granulosa cell TIP to ovarian follicular incubation at a dose of 5 microg/ml significantly increased (P < 0.01) 3beta-HSD activity. To observe whether TIP acts directly on the enzyme or not, 3beta-HSD from perch ovarian follicle was purified to homogeneity by the following steps: (i) Sephadex G 75 gel filtration, (ii) DEAE-Sephacel chromatography, and (iii) NAD-affinity column chromatography. Purified 3beta-HSD gave a clear single band on an SDS gel and its molecular weight is 45 kDa. Addition of fTIP to an assay mixture containing purified 3beta-HSD resulted in a fourfold increase of the enzyme activity. fTIP alone did not show enzyme activity when incubated with the radiolabeled substrate. Addition of T3 (50 ng) to the 3beta-HSD assay mixture had no effect on the enzyme activity. Determination of Vmax and Km of the purified enzyme in the absence (control) and presence of fTIP demonstrated a considerable increase of 3beta-HSD affinity and rate of enzyme reaction.
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Affiliation(s)
- M Datta
- Department of Zoology, School of Life Sciences, Santiniketan, West Bengal, 731235, India
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Trant JM. Isolation and characterization of the cDNA encoding the spiny dogfish shark (Squalus acanthias) form of cytochrome P450c17. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1995; 272:25-33. [PMID: 7738515 DOI: 10.1002/jez.1402720104] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Cytochrome P450c17 is a key steroidogenic enzyme for the production of sex steroids in gonadal tissue and for cortisol production in adrenal tissue. This protein possesses two enzymatic activities. The 17 alpha-hydroxylase activity results in the introduction of a hydroxyl group at the 17 alpha-position. The resultant 17 alpha-hydroxylated, C21 pregnene is converted to a C19 androgen by the C17,20-lyase activity. A cDNA library was constructed from poly(A)-enriched mRNA isolated from spiny dogfish shark (Squalus acanthias) testis and ligated into EcoRI-cut lambda arms. The amplified library was screened using a bovine P450c17 cDNA probe and five positive clones were isolated. The described cDNA encompasses 23 bp of the 5'-untranslated region, a 1,527 bp open reading frame, and 414 bp of the 3'-untranslated region. A putative polyadenylation signal (AATAAA) is 18 bp from the poly(A) tail. Northern blot analysis showed a single transcript of 1.9 kb, thus indicating the isolated clone is a full-length cDNA. The deduced amino acid sequence of the shark form of P450c17 is 59% and 57% identical to the rainbow trout and chicken forms, respectively. The shark form is 43% to 46% identical to mammalian forms (rat, human, mouse, bovine, and porcine). There are large regions of extremely high identity shared among all the forms. The deduced shark 17 alpha-hydroxylase protein is 509 residues in length with a predicted weight of 57.2 kDa. Non-steroidogenic COS cells, transfected with the shark P450c17 cDNA, was capable of 17 alpha-hydroxylase and C17,20-lyase activities using both pregnenolone and progesterone as initial substrates.
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Affiliation(s)
- J M Trant
- Department of Zoology and Physiology, Louisiana State University, Baton Rouge 70803, USA
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Buczko E, Koh YC, Miyagawa Y, Dufau ML. The rat 17 alpha-hydroxylase-17,20-desmolase (CYP17) active site: computerized homology modeling and site directed mutagenesis. J Steroid Biochem Mol Biol 1995; 52:209-18. [PMID: 7696141 DOI: 10.1016/0960-0760(94)00174-k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A homology model of the rat 17 alpha-hydroxylase-17,20 desmolase (CYP17) steroid binding domain was derived from the alpha/beta F supersecondary structural element of the 3 alpha/20 beta hydroxysteroid dehydrogenase (HSD) of Streptomyces hydrogenans that constitutes a major segment of the C19 steroid binding cavity. A CYP17 arginine-rich domain, including Arg346, Arg361 and Arg363, that has previously been shown to be important to CYP17 catalytic activity, is conserved in this HSD structural element between two HSD domains known to be important to C19 steroid binding. These two HSD motifs, in addition to a C-terminal domain at the apex of the steroid binding cavity, are also present in similar though not identical forms in the rat CYP17 sequence. The model was evaluated in terms of both hydroxylase/lyase activity and stability of CYP17 mutant proteins (Tyr334Phe, Phe343Ile, Arg357Ala, Arg361Ala, Asp345Ala), and further tested with mutagenesis of Glu353, Glu358, and Tyr431. Those amino acids located at folding junctions in the model steroid binding domain (Glu358, Arg361, and Tyr431) are each individually required to prevent degradation of the nascent protein, as well as for basic hydroxylase/lyase activity. Genomic analysis of the rat CYP17 gene reveals that this domain is contained in exon 6, and a correlation exists between the length of exon 6 and the boundaries of the HSD supersecondary element. These studies demonstrate that exon 6 of the rat CYP17 is essential for CYP17 activity, and may be structurally related to the NAD-linked prokaryote alpha/beta F supersecondary element.
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Affiliation(s)
- E Buczko
- Section on Molecular Endocrinology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
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O'Brien EP, Novak EK, Keller SA, Poirier C, Guénet JL, Swank RT. Molecular map of chromosome 19 including three genes affecting bleeding time: ep, ru, and bm. Mamm Genome 1994; 5:356-60. [PMID: 8043950 DOI: 10.1007/bf00356554] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The mouse ruby eye (ru) and pale ear (ep) pigment dilution genes cause platelet storage pool deficiency (SPD) and prolonged bleeding times. The brachymorphic (bm) gene, in addition to causing skeletal abnormalities, is also associated with prolonged bleeding times. All three hemorrhagic genes are found within 10 cM on Chromosome (Chr) 19. In this study, 15 microsatellite markers and five cDNAs, spanning 21 cM of Chr 19, were mapped in relation to the bm, ep, and ru genes in 457 progeny of an interspecific backcross utilizing the highly inbred strain PWK derived from the Mus musculus musculus species. Several markers were found to be closely linked to the three genes and should be useful as entry points in their eventual molecular identification.
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Affiliation(s)
- E P O'Brien
- Molecular and Cellular Biology Department, Roswell Park Cancer Institute, Buffalo, New York 14263
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Kölble K. Regional mapping of short tandem repeats on human chromosome 10: cytochrome P450 gene CYP2E, D10S196, D10S220, and D10S225. Genomics 1993; 18:702-4. [PMID: 8307581 DOI: 10.1016/s0888-7543(05)80378-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Human CYP2E encodes an ethanol-inducible cytochrome P450 monooxygenase that metabolizes various carcinogens and may therefore play a role in cancer susceptibility. An intronic (GGAT)n.(CCTA)n repeat element was found to display limited polymorphism in Caucasoids and was used as a sequence-tagged site for genomic amplification from somatic cell hybrids to localize CYP2E to 10q24.3-qter; using the same panel, three microsatellite markers, D10S196, D10S220, and D10S225, were mapped to 10q21. The close synteny of CYP2E, CYP2C, and CYP17 belonging to two different cytochrome P450 families suggests a central role for the long arm of chromosome 10 in the evolution of this large gene superfamily.
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Affiliation(s)
- K Kölble
- Department of Biochemistry, University of Oxford, United Kingdom
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Expression and purification of functional human 17 alpha-hydroxylase/17,20-lyase (P450c17) in Escherichia coli. Use of this system for study of a novel form of combined 17 alpha-hydroxylase/17,20-lyase deficiency. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(19)36570-6] [Citation(s) in RCA: 115] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Nelson DR, Kamataki T, Waxman DJ, Guengerich FP, Estabrook RW, Feyereisen R, Gonzalez FJ, Coon MJ, Gunsalus IC, Gotoh O. The P450 superfamily: update on new sequences, gene mapping, accession numbers, early trivial names of enzymes, and nomenclature. DNA Cell Biol 1993; 12:1-51. [PMID: 7678494 DOI: 10.1089/dna.1993.12.1] [Citation(s) in RCA: 1077] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We provide here a list of 221 P450 genes and 12 putative pseudogenes that have been characterized as of December 14, 1992. These genes have been described in 31 eukaryotes (including 11 mammalian and 3 plant species) and 11 prokaryotes. Of 36 gene families so far described, 12 families exist in all mammals examined to date. These 12 families comprise 22 mammalian subfamilies, of which 17 and 15 have been mapped in the human and mouse genome, respectively. To date, each subfamily appears to represent a cluster of tightly linked genes. This revision supersedes the previous updates [Nebert et al., DNA 6, 1-11, 1987; Nebert et al., DNA 8, 1-13, 1989; Nebert et al., DNA Cell Biol. 10, 1-14 (1991)] in which a nomenclature system, based on divergent evolution of the superfamily, has been described. For the gene and cDNA, we recommend that the italicized root symbol "CYP" for human ("Cyp" for mouse), representing "cytochrome P450," be followed by an Arabic number denoting the family, a letter designating the subfamily (when two or more exist), and an Arabic numeral representing the individual gene within the subfamily. A hyphen should precede the final number in mouse genes. "P" ("p" in mouse) after the gene number denotes a pseudogene. If a gene is the sole member of a family, the subfamily letter and gene number need not be included. We suggest that the human nomenclature system be used for all species other than mouse. The mRNA and enzyme in all species (including mouse) should include all capital letters, without italics or hyphens. This nomenclature system is identical to that proposed in our 1991 update. Also included in this update is a listing of available data base accession numbers for P450 DNA and protein sequences. We also discuss the likelihood that this ancient gene superfamily has existed for more than 3.5 billion years, and that the rate of P450 gene evolution appears to be quite nonlinear. Finally, we describe P450 genes that have been detected by expressed sequence tags (ESTs), as well as the relationship between the P450 and the nitric oxide synthase gene superfamilies, as a likely example of convergent evolution.
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Affiliation(s)
- D R Nelson
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill 27599
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Hanukoglu I. Steroidogenic enzymes: structure, function, and role in regulation of steroid hormone biosynthesis. J Steroid Biochem Mol Biol 1992; 43:779-804. [PMID: 22217824 DOI: 10.1016/0960-0760(92)90307-5] [Citation(s) in RCA: 335] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In the pathways of steroid hormone biosynthesis there are two major types of enzymes: cytochromes P450 and other steroid oxidoreductases. This review presents an overview of the function and expression of both types of enzymes with emphasis on steroidogenic P450s. The final part of the review on regulation of steroidogenesis includes a description of the normal physiological fluctuations in the steroid output of adrenal cortex and gonads, and provides an analysis of the relative role of enzyme levels in the determination of these fluctuations. The repertoire of enzymes expressed in a steroidogenic cell matches the cell's capacity for the biosynthesis of specific steroids. Thus, steroidogenic capacity is regulated mainly by tissue and cell specific expression of enzymes, and not by selective activation or inhibition of enzymes from a larger repertoire. The quantitative capacity of steroidogenic cells for the biosynthesis of specific steroids is determined by the levels of steroidogenic enzymes. The major physiological variations in enzyme levels, are generally associated with parallel changes in gene expression. The level of expression of each steroidogenic enzyme varies in three characteristics: (a) tissue- and cell-specific expression, determined during tissue and cell differentiation; (b) basal expression, in the absence of trophic hormonal stimulation; and (c) hormonal signal regulated expression. Each of these three types of expression probably represent the functioning of distinct gene regulatory elements. In adult steroidogenic tissues, the levels of most of the cell- and tissue-specific steroidogenic enzymes depend mainly on trophic hormonal stimulation mediated by a complex network of signal transduction systems.
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Affiliation(s)
- I Hanukoglu
- Department of Hormone Research, Weizmann Institute of Science, Rehovot, Israel
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Fan YS, Sasi R, Lee C, Winter JS, Waterman MR, Lin CC. Localization of the human CYP17 gene (cytochrome P450(17 alpha)) to 10q24.3 by fluorescence in situ hybridization and simultaneous chromosome banding. Genomics 1992; 14:1110-1. [PMID: 1478654 DOI: 10.1016/s0888-7543(05)80140-5] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The gene for human P450(17 alpha) (CYP17) was previously mapped to chromosome 10 through analysis of somatic cell hybrids. Using a modified procedure of fluorescence in situ hybridization, this gene has now been visualized on simultaneously banded chromosomes and localized to a specific subband of chromosome 10 at q24.3. This precise assignment may facilitate the understanding of the molecular basis of 17 alpha-hydroxylase/17,20-lyase deficiency and the evolution of the CYP superfamily of genes.
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Affiliation(s)
- Y S Fan
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Canada
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Nadeau JH, Davisson MT, Doolittle DP, Grant P, Hillyard AL, Kosowsky MR, Roderick TH. Comparative map for mice and humans. Mamm Genome 1992; 3:480-536. [PMID: 1392257 DOI: 10.1007/bf00778825] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- J H Nadeau
- Jackson Laboratory, Bar Harbor, Maine 04609
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