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Geisert RD, Bazer FW, Lucas CG, Pfeiffer CA, Meyer AE, Sullivan R, Johns DN, Sponchiado M, Prather RS. Maternal recognition of pregnancy in the pig: A servomechanism involving sex steroids, cytokines and prostaglandins. Anim Reprod Sci 2024; 264:107452. [PMID: 38522133 DOI: 10.1016/j.anireprosci.2024.107452] [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: 01/30/2024] [Revised: 03/07/2024] [Accepted: 03/08/2024] [Indexed: 03/26/2024]
Abstract
Maternal recognition of pregnancy (MRP) is a term utilized in mammals to describe pathways in which the conceptus alters the endometrial environment to prevent regression of corpora lutea to ensure continued production of progesterone (P4) required for establishment and maintenance of pregnancy. For nearly 40 years after publication of the endocrine/exocrine theory, conceptus estrogen (E2) was considered the primary maternal recognition signal in the pig. Conceptus production of prostaglandin E2 (PGE2) was also considered to be a major factor in preventing luteolysis. An addition to E2 and PGE2, pig conceptuses produce interleukin 1B2 (IL1B2) and interferons (IFN) delta (IFND) and gamma (IFNG). The present review provides brief history of the discovery of E2, PGs and IFNS which led to research investigating the role of these conceptus secreted factors in establishing and maintaining pregnancy in the pig. The recent utilization of gene editing technology allowed a more direct approach to investigate the in vivo roles of IL1B2, E2, PGE2, AND IFNG for establishment of pregnancy. These studies revealed unknown functions for IFNG and ILB2 in addition to PGE2 and E2. Thus, pregnancy recognition signal is via a servomechanism in requiring sequential effects of P4, E2, IL1B2, PGE2 and IFNG. Results indicate that the original established dogma for the role of conceptus E2 and PGs in MRP is a far too simplified model that involves the interplay of numerous mechanisms for inhibiting luteolysis, inducing critical elongation of the conceptuses and resolution of inflammation in pigs.
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Affiliation(s)
- Rodney D Geisert
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA.
| | - Fuller W Bazer
- Department of Animal Science, Texas A&M University, College Station, TX 77843, USA
| | - Caroline G Lucas
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Caroline A Pfeiffer
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Ashley E Meyer
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Riley Sullivan
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Destiny N Johns
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Mariana Sponchiado
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Randall S Prather
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
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2
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Yazawa T, Imamichi Y, Sato T, Ida T, Umezawa A, Kitano T. Diversity of Androgens; Comparison of Their Significance and Characteristics in Vertebrate Species. Zoolog Sci 2024; 41:77-86. [PMID: 38587520 DOI: 10.2108/zs230064] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Accepted: 10/31/2023] [Indexed: 04/09/2024]
Abstract
Androgen(s) is one of the sex steroids that are involved in many physiological phenomena of vertebrate species. Although androgens were originally identified as male sex hormones, it is well known now that they are also essential in females. As in the case of other steroid hormones, androgen is produced from cholesterol through serial enzymatic reactions. Although testis is a major tissue to produce androgens in all species, androgens are also produced in ovary and adrenal (interrenal tissue). Testosterone is the most common and famous androgen. It represents a major androgen both in males and females of almost vertebrate species. In addition, testosterone is a precursor for producing significant androgens such as11-ketotestosterone, 5α-dihydrotestosterone, 11-ketodihydrotestosterones and 15α-hydroxytestosterone in a species- or sex-dependent manner for their homeostasis. In this article, we will review the significance and characteristics of these androgens, following a description of the history of testosterone discovery and its synthetic pathways.
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Affiliation(s)
- Takashi Yazawa
- Department of Biochemistry, Asahikawa Medical University, Hokkaido 078-8510, Japan,
| | - Yoshitaka Imamichi
- Faculty of Marine Science and Technology, Fukui Prefectural University, Fukui 917-0003, Japan,
| | - Takahiro Sato
- Division of Molecular Genetics, Institute of Life Sciences, Kurume University, Fukuoka 830-0011, Japan
| | - Takanori Ida
- Center for Animal Disease Control, Frontier Science Research Center, University of Miyazaki, Miyazaki 889-1692, Japan
| | - Akihiro Umezawa
- National Center for Child Health and Development Research Institute, Tokyo 157-8535, Japan
| | - Takeshi Kitano
- Department of Biological Sciences, Graduate School of Science and Technology, Kumamoto University, Kumamoto 860-8555, Japan
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3
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Electromagnetic field exposure alters in vitro estrogen biosynthesis and its release by the porcine endometrium in the peri-implantation period. Reprod Biol 2022; 22:100642. [PMID: 35487179 DOI: 10.1016/j.repbio.2022.100642] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/01/2022] [Accepted: 04/14/2022] [Indexed: 11/22/2022]
Abstract
The electromagnetic field (EMF) is an environmental risk factor that may impair living organisms. This study aims to determine the functional effects of EMF exposure at 50 and 120 Hz for 2 or 4 h on estrogen synthesis and release in the endometrium. Endometrial slices were isolated from pigs (n = 5) during the peri-implantation period. To check whether progesterone (P4) exerts any protective effects against EMF, selected EMF-treated slices were also treated with P4. CYP19A3 mRNA transcript abundance was higher in slices exposed to EMF (50 Hz, 4 h) and treated with P4. HSD17B4 mRNA transcript abundance was higher in slices exposed to EMF (50 and 120 Hz, 2 h) without P4 treatment. Both EMF (50 Hz, 2 h) and EMF (50 and 120 Hz, 4 h) increased HSD17B4 mRNA transcript abundance in the presence of P4; EMF (120 Hz, 2 h, and 50 Hz, 4 h) decreased cytochrome P-450arom protein abundance in tissue slices not treated with P4. Under exposure to EMF at 120 Hz (2 h), the abundance of hydroxysteroid 17β dehydrogenase decreased in P4-treated slices and increased in slices not treated with P4 (4 h). Progesterone treatment decreased the release of estradiol-17β (E2) in endometrial slices exposed to EMF at 50 Hz (2 h), whereas in slices not treated with P4, EMF (120 Hz, 2 h) increased estrone (E1) release compared to control (without EMF). The EMF could disrupt the synthesis and release of E1 and E2 by the porcine endometrium during the peri-implantation period.
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4
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Berger T, Vanselow J, Conley A, Almand TJ, Nitta-Oda BS. Multifaceted epigenetic regulation of porcine testicular aromatase. Mol Cell Endocrinol 2022; 541:111526. [PMID: 34856344 DOI: 10.1016/j.mce.2021.111526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/27/2021] [Accepted: 11/28/2021] [Indexed: 11/20/2022]
Abstract
Testicular aromatase catalyzes the synthesis of estradiol, which contributes to regulation of porcine Sertoli cell proliferation and postpubertal maintenance of Sertoli cell numbers. Although aromatase enzymatic activity decreases with age and is persistently reprogrammed by prepubertal treatment with the aromatase inhibitor letrozole, the molecular bases for regulation have not been identified. DNA methylation was examined as a potential regulatory mechanism using DNA from Leydig cells isolated from 16-, 40-, and 68-week-old boars and from 68- week-old littermates treated with the aromatase inhibitor, letrozole. Methylation levels of individual CpG dinucleotides located in the distal untranslated exon 1 of the relevant aromatase encoding gene, CYP19A3, were quite high in Leydig cell DNA, and increased further with maturity of boar (P < 0.05), while aromatase activity and transcript abundance decreased more than two-fold. However, reduced aromatase activity following letrozole treatment was not accompanied by altered DNA methylation. Testicular expression of miR378 was altered by prepubertal treatment with letrozole. The data provide evidence for two different epigenetic mechanisms that regulate aromatase expression and enzymatic activity in the boar testis.
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Affiliation(s)
- Trish Berger
- Department of Animal Science, College of Agricultural and Environmental Sciences, University of California, Davis, CA, USA.
| | - Jens Vanselow
- Research Institute for Farm Animal Biology FBN, Wilhelm-Stahl-Allee 2, 18196, Dummerstorf, Germany.
| | - Alan Conley
- Department of Population Health & Reproduction, School of Veterinary Medicine, University of California, Davis, CA, USA.
| | - Tana Jo Almand
- Department of Animal Science, College of Agricultural and Environmental Sciences, University of California, Davis, CA, USA.
| | - Barbara S Nitta-Oda
- Department of Animal Science, College of Agricultural and Environmental Sciences, University of California, Davis, CA, USA.
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Costermans NGJ, Soede NM, van Tricht F, Blokland M, Kemp B, Keijer J, Teerds KJ. Follicular fluid steroid profile in sows: relationship to follicle size and oocyte quality†. Biol Reprod 2021; 102:740-749. [PMID: 31786607 PMCID: PMC7068110 DOI: 10.1093/biolre/ioz217] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 11/21/2019] [Accepted: 11/26/2019] [Indexed: 12/19/2022] Open
Abstract
Identification of reliable characteristics of follicle quality and developmental competence has been pursued in numerous studies, but with inconsistent outcomes. Here, we aimed to identify these characteristics by analysis of the follicular fluid (FF) steroid profile in relation to cumulus-oocyte complex (COC) morphology and follicle size, followed by molecular substantiation. Multiparous sows at weaning were used to facilitate analysis at the start of the follicular phase of the oestrus cycle. Sows with a higher average follicle size (≥5 mm vs. < 5 mm) had a higher follicular fluid β-estradiol concentration, but did not differ in other measured steroids. Sows with high compared to low percentage high-quality COCs (<70% vs. ≥70% high-quality) had follicular fluid with a higher concentration of β-estradiol, 19-norandrostenedione, progesterone, and α-testosterone, while the concentration of cortisol was lower. Transcriptome analysis of granulosa cells of healthy follicles of sows with a high percentage high-quality COCs showed higher abundance of transcripts involved in ovarian steroidogenesis (e.g., CYP19A2 and 3, POR, VEGFA) and growth (IGF1) and differential abundance of transcripts involved in granulosa cell apoptosis (e.g., GADD45A, INHBB). Differences in aromatase transcript abundance (CYP19A1, 2 and 3) were confirmed at the protein level. In addition, sows with a high percentage high-quality COCs lost less weight during lactation and had higher plasma IGF1 concentration at weaning, which may have affected COC quality. To the best of our knowledge, this study is also the first to report the relation between FF steroid profile and COC quality.
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Affiliation(s)
- N G J Costermans
- Human and Animal Physiology, Wageningen University and Research, Wageningen, The Netherlands.,Adaptation Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - N M Soede
- Adaptation Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - F van Tricht
- Wageningen Food Safety Research (WFSR), Wageningen University and Research, Wageningen, The Netherlands
| | - M Blokland
- Wageningen Food Safety Research (WFSR), Wageningen University and Research, Wageningen, The Netherlands
| | - B Kemp
- Adaptation Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - J Keijer
- Human and Animal Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - K J Teerds
- Human and Animal Physiology, Wageningen University and Research, Wageningen, The Netherlands
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Correlation Networks Provide New Insights into the Architecture of Testicular Steroid Pathways in Pigs. Genes (Basel) 2021; 12:genes12040551. [PMID: 33918852 PMCID: PMC8069258 DOI: 10.3390/genes12040551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 12/19/2022] Open
Abstract
Steroid metabolism is a fundamental process in the porcine testis to provide testosterone but also estrogens and androstenone, which are essential for the physiology of the boar. This study concerns boars at an early stage of puberty. Using a RT-qPCR approach, we showed that the transcriptional activities of several genes providing key enzymes involved in this metabolism (such as CYP11A1) are correlated. Surprisingly, HSD17B3, a key gene for testosterone production, was absent from this group. An additional weighted gene co-expression network analysis was performed on two large sets of mRNA-seq to identify co-expression modules. Of these modules, two containing either CYP11A1 or HSD17B3 were further analyzed. This comprehensive correlation meta-analysis identified a group of 85 genes with CYP11A1 as hub gene, but did not allow the characterization of a robust correlation network around HSD17B3. As the CYP11A1-group includes most of the genes involved in steroid synthesis pathways (including LHCGR encoding for the LH receptor), it may control the synthesis of most of the testicular steroids. The independent expression of HSD17B3 probably allows part of the production of testosterone to escape this control. This CYP11A1-group contained also INSL3 and AGT genes encoding a peptide hormone and an angiotensin peptide precursor, respectively.
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Genomic Structure of the Porcine CYP19 Locus and Expression of the CYP19A3 Paralog. Genes (Basel) 2021; 12:genes12040533. [PMID: 33917597 PMCID: PMC8067493 DOI: 10.3390/genes12040533] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 03/30/2021] [Accepted: 04/05/2021] [Indexed: 11/17/2022] Open
Abstract
Proper, tissue-specific regulation of CYP19, the gene encoding aromatase, the key enzyme of estrogen synthesis, is essential for reproductive processes. Here, we analyzed transcriptional regulation of the porcine CYP19 in female and male gonads and brain by 5'RACE and RT-PCR and comprehensively mapped the pig CYP19 locus by in silico analysis. Our data revealed that the complete locus, including three paralogous copies, CYP19A1, CYP19A2 and CYP19A3, spans approximately 330 kb of the porcine chromosome 1. The locus also harbors the first exon of the Gliomedin gene (GLDN) in reverse orientation. Only transcripts of the CYP19A3 paralog were substantially expressed in gonads and hypothalamus. We identified CYP19A3-associated untranslated exons approximately 160 kb and 50 kb distal from the first codon. The 5´ untranslated regions of transcripts were derived from either a proximal or from one of these distal untranslated exons. Transcripts including only untranslated exons could be amplified from testis, thus suggesting long non-coding transcripts. The data revealed an additional layer of complexity in the regulation of the porcine CYP19 locus. Tissue-specific expression is not only achieved by tissue- and stage-specific expression of the three different CYP19 paralogs, but also by directing the expression of CYP19A3 from different, proximal and distal promoter regions.
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Meng L, Zhao K, Wang CC, Tao J, Wu Z, Teerds K, Zhang S. Characterization of Long Non-Coding RNA Profiles in Porcine Granulosa Cells of Healthy and Atretic Antral Follicles: Implications for a Potential Role in Apoptosis. Int J Mol Sci 2021; 22:ijms22052677. [PMID: 33800928 PMCID: PMC7962063 DOI: 10.3390/ijms22052677] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 02/23/2021] [Accepted: 03/01/2021] [Indexed: 12/13/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) play important roles in multiple biological processes including ovarian follicular development. Here we aimed to gain novel information regarding lncRNAs transcriptome profiles in porcine granulosa cells of advanced atretic antral (AA) and healthy antral (HA) follicles using RNA-seq. A total of 11,321 lncRNAs including 10,813 novel and 508 annotated lncRNAs were identified, of which 173 lncRNAs were differentially expressed (DE-lncRNAs); ten of these were confirmed by qRT-PCR. Gene Ontology indicated that DE-lncRNAs associated with developmental processes were highly enriched. Pathway analysis demonstrated predicted cis- and trans-targets of DE-lncRNAs. Potential mRNA targets of up-regulated DE-lncRNAs were mainly enriched in apoptosis related pathways, while targeted genes of downregulated DE-lncRNAs were primarily enriched in metabolism and ovarian steroidogenesis pathways. Linear regression analyses showed that expression of upregulated DE-lncRNAs was significantly associated with apoptosis related genes. NOVEL_00001850 is the most-downregulated DE-lncRNA (FDR = 0.04, FC = -6.53), of which miRNA binding sites were predicted. KEGG analysis of its downregulated target genes revealed that ovarian steroidogenesis was the second most highlighted pathway. qRT-PCR and linear regression analysis confirmed the expression and correlation of its potential targeted gene, CYP19A1, a key gene involved in estradiol synthesis. Our results indicate that lncRNAs may participate in granulosa cells apoptosis and thus antral follicular atresia.
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Affiliation(s)
- Li Meng
- National Engineering Research Center of Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; (L.M.); (K.Z.); (J.T.); (Z.W.)
- Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Key Lab of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Department of Obstetrics & Gynaecology, Li Ka Shing Institute of Health Sciences, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China;
| | - Kun Zhao
- National Engineering Research Center of Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; (L.M.); (K.Z.); (J.T.); (Z.W.)
- Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Key Lab of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
| | - Chi Chiu Wang
- Department of Obstetrics & Gynaecology, Li Ka Shing Institute of Health Sciences, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China;
| | - Jian Tao
- National Engineering Research Center of Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; (L.M.); (K.Z.); (J.T.); (Z.W.)
- Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Key Lab of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
| | - Zhenfang Wu
- National Engineering Research Center of Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; (L.M.); (K.Z.); (J.T.); (Z.W.)
- Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Key Lab of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
| | - Katja Teerds
- Human and Animal Physiology, Wageningen University, De Elst 1, 6708 WD Wageningen, The Netherlands
- Correspondence: (K.T.); (S.Z.)
| | - Shouquan Zhang
- National Engineering Research Center of Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; (L.M.); (K.Z.); (J.T.); (Z.W.)
- Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Key Lab of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Correspondence: (K.T.); (S.Z.)
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Transcriptome Analysis of Porcine Granulosa Cells in Healthy and Atretic Follicles: Role of Steroidogenesis and Oxidative Stress. Antioxidants (Basel) 2020; 10:antiox10010022. [PMID: 33379347 PMCID: PMC7824097 DOI: 10.3390/antiox10010022] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 12/20/2020] [Accepted: 12/22/2020] [Indexed: 12/14/2022] Open
Abstract
One of the main causes of female infertility is a deregulated antral follicular atresia, a process of which the underlying molecular mechanisms are largely unknown. Our objective was therefore to characterize the complex transcriptome changes in porcine granulosa cells of healthy antral (HA) and advanced antral atretic (AA) follicles, using ELISA and RNA-Seq followed by qRT-PCR and immunohistochemistry. Granulosa cell RNA-Seq data revealed 2160 differentially expressed genes, 1483 with higher and 677 with lower mRNA concentrations in AA follicles. Bioinformatic analysis showed that the upregulated genes in AA follicles were highly enriched in inflammation and apoptosis processes, while the downregulated transcripts were mainly highlighted in the steroid biosynthesis pathway and response to oxidative stress processes including antioxidant genes (e.g., GSTA1, GCLC, GCLM, IDH1, GPX8) involved in the glutathione metabolism pathway and other redox-related genes (e.g., RRM2B, NDUFS4). These observations were confirmed by RT-qPCR and immunohistochemistry. Additionally, the granulosa cells of AA follicles express significantly stronger 8-OHdG immunostaining, a marker of oxidative DNA damage, implicating that oxidative stress may participate in follicular atresia. We hypothesize that the decrease in anti-apoptotic factors and steroid hormones coincides with increased oxidative stress markers and the expression of pro-apoptotic factors, all contributing to antral follicular atresia.
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Lin CJ, Maugars G, Lafont AG, Jeng SR, Wu GC, Dufour S, Chang CF. Basal teleosts provide new insights into the evolutionary history of teleost-duplicated aromatase. Gen Comp Endocrinol 2020; 291:113395. [PMID: 31981691 DOI: 10.1016/j.ygcen.2020.113395] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 01/04/2020] [Accepted: 01/20/2020] [Indexed: 11/25/2022]
Abstract
Duplicated cyp19a1 genes (cyp19a1a encoding aromatase a and cyp19a1b encoding aromatase b) have been identified in an increasing number of teleost species. Cyp19a1a is mainly expressed in the gonads, while cyp19a1b is mainly expressed in the brain, specifically in radial glial cells, as largely investigated by Kah and collaborators. The third round of whole-genome duplication that specifically occurred in the teleost lineage (TWGD or 3R) is likely at the origin of the duplicated cyp19a1 paralogs. In contrast to the situation in other teleosts, our previous studies identified a single cyp19a1 in eels (Anguilla), which are representative species of a basal group of teleosts, Elopomorpha. In the present study, using genome data mining and phylogenetic and synteny analyses, we confirmed that the whole aromatase genomic region was duplicated in eels, with most aromatase-neighboring genes being conserved in duplicate in eels, as in other teleosts. These findings suggest that specific gene loss of one of the 3R-duplicated cyp19a1 paralogs occurred in Elopomorpha after TWGD. Similarly, a single cyp19a1 gene was found in the arowana, which is a representative species of another basal group of teleosts, Osteoglossomorpha. In eels, the single cyp19a1 is expressed in both the brain and the gonads, as observed for the single CYP19A1 gene present in other vertebrates. The results of phylogenetic, synteny, closest neighboring gene, and promoter structure analyses showed that the single cyp19a1 of the basal teleosts shared conserved properties with both teleost cyp19a1a and cyp19a1b paralogs, which did not allow us to conclude which of the 3R-duplicated paralogs (cyp19a1a or cyp19a1b) was lost in Elopomorpha. Elopomorpha and Osteoglossomorpha cyp19a1 genes exhibited preserved ancestral functions, including expression in both the gonad and brain. We propose that the subfunctionalization of the 3R-duplicated cyp19a1 paralogs expressed specifically in the gonad or brain occurred in Clupeocephala, after the split of Clupeocephala from Elopomorpha and Osteoglossomorpha, which represented a driving force for the conservation of both 3R-duplicated paralogs in all extant Clupeocephala. In contrast, the functional redundancy of the undifferentiated 3R-duplicated cyp19a1 paralogs in elopomorphs and osteoglossomorphs would have favored the loss of one 3R paralog in basal teleosts.
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Affiliation(s)
- Chien-Ju Lin
- Department of Aquaculture, National Taiwan Ocean University, Keelung 20224, Taiwan; Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 20224, Taiwan
| | - Gersende Maugars
- Laboratory Biology of Aquatic Organisms and Ecosystems (BOREA), Muséum National d'Histoire Naturelle, CNRS, IRD, Sorbonne Université, Université de Caen Normandie, Université des Antilles, 75231 Paris Cedex 05, France
| | - Anne-Gaëlle Lafont
- Laboratory Biology of Aquatic Organisms and Ecosystems (BOREA), Muséum National d'Histoire Naturelle, CNRS, IRD, Sorbonne Université, Université de Caen Normandie, Université des Antilles, 75231 Paris Cedex 05, France
| | - Shan-Ru Jeng
- Department of Aquaculture, National Kaohsiung University of Science and Technology, Kaohsiung 811, Taiwan
| | - Guan-Chung Wu
- Department of Aquaculture, National Taiwan Ocean University, Keelung 20224, Taiwan; Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 20224, Taiwan
| | - Sylvie Dufour
- Laboratory Biology of Aquatic Organisms and Ecosystems (BOREA), Muséum National d'Histoire Naturelle, CNRS, IRD, Sorbonne Université, Université de Caen Normandie, Université des Antilles, 75231 Paris Cedex 05, France.
| | - Ching-Fong Chang
- Department of Aquaculture, National Taiwan Ocean University, Keelung 20224, Taiwan; Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 20224, Taiwan.
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11
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Aromatase expression and function in the brain and behavior: A comparison across communication systems in teleosts. J Chem Neuroanat 2018; 94:139-153. [DOI: 10.1016/j.jchemneu.2018.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/09/2018] [Accepted: 10/14/2018] [Indexed: 11/18/2022]
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12
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Martyniak M, Franczak A, Kotwica G. Synthesis of steroid hormones in the porcine oviduct during early pregnancy. Reprod Biol 2018; 18:143-150. [DOI: 10.1016/j.repbio.2018.02.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 02/04/2018] [Accepted: 02/08/2018] [Indexed: 10/18/2022]
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13
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LaVoie HA. Transcriptional control of genes mediating ovarian follicular growth, differentiation, and steroidogenesis in pigs. Mol Reprod Dev 2017; 84:788-801. [DOI: 10.1002/mrd.22827] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/28/2017] [Accepted: 05/01/2017] [Indexed: 01/01/2023]
Affiliation(s)
- Holly A. LaVoie
- Deptartment of Cell Biology and AnatomyUniversity of South Carolina School of MedicineColumbiaSouth Carolina
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14
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Martyniak M, Zglejc K, Franczak A, Kotwica G. Expression of 3β-hydroxysteroid dehydrogenase and P450 aromatase in porcine oviduct during the oestrous cycle. JOURNAL OF ANIMAL AND FEED SCIENCES 2016. [DOI: 10.22358/jafs/65557/2016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Chaube R, Rawat A, Joy KP. Molecular cloning and characterization of brain and ovarian cytochrome P450 aromatase genes in the catfish Heteropneustes fossilis: Sex, tissue and seasonal variation in, and effects of gonadotropin on gene expression. Gen Comp Endocrinol 2015; 221:120-33. [PMID: 26144886 DOI: 10.1016/j.ygcen.2015.06.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 05/28/2015] [Accepted: 06/08/2015] [Indexed: 11/22/2022]
Abstract
Cytochrome P450 aromatase (Cyp19arom) is the rate-limiting enzyme controlling estrogen biosynthesis, coded by Cyp19a1 in most gnathostomes. Most teleosts have two forms expressed differentially in ovary (cyp19a1a) and neural tissue (cyp19a1b). In this study, full length cDNAs of 2006 bp and 1913 bp with ORFs of 1575 bp and 1488 bp were isolated from the brain and ovary, respectively, of the catfish Heteropneustes fossilis, an air-breathing species with high aquaculture potential. The ORFs encode predicted proteins of 495 and 524 amino acid residues, respectively. The proteins show 62% identity with each other and cluster in two distinct clades (the brain type and ovary type) in the teleost taxon, separated from the tetrapod type. In the in situ localization study, both cyp19a1a and cyp19a1b transcripts were localized in the brain but the signal intensity was higher for the brain type paralog. The transcript signals were observed in the radial glial cells and in neuronal populations of the dorso-lateral region of the telencephalon, pre-tectum, hypothalamus and medulla oblongata. In the ovary, both paralogs were expressed in the follicular layer with a high signal intensity of the ovarian type (cyp19a1a). The differential expression of the gene paralogs was evident from qPCR analysis. Cyp19a1b has relatively a high abundance in the female brain, followed by other peripheral tissues (gonads, liver, gill, kidney and muscle). On the other hand, cyp19a1a has relatively a high transcript abundance in the ovary and female brain, followed by the testis and male brain, and female liver and muscle. The expression was low in male liver and muscle, and the lowest in the gill and kidney. The expression of the two paralogs exhibit brain regional differences; both types have relatively a high transcript abundance in telencephalon-preoptic area with the cyp19a1b expression higher in females than males. In hypothalamus, the expression of both types is higher in males than females. In medulla, the expression of the cyp19a1b is higher than cyp19a1a, and the transcript abundance of the ovarian type is higher in females than males. The expression of the gene paralogs elicits significant seasonal variations in the ovary and brain. In both tissues, the expression increases from the resting to preparatory phases, and decreases through the prespawning phase to low levels in spawning phase. In vivo and/or in vitro treatments with human chorionic gonadotropin (hCG) stimulated the expression of the gene paralogs in the brain and ovary, time-dependently. In conclusion, both paralogs have an overlapping distribution at different levels of the brain-pituitary-gonad axis and may function as a single functional unit as far as the estrogen synthesis is concerned.
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Affiliation(s)
- Radha Chaube
- Zoology Department, Mahila Mahavidyalaya, Banaras Hindu University, Varanasi 221005, India.
| | - Arpana Rawat
- Department of Zoology, Centre of Advanced Study, Banaras Hindu University, Varanasi 221005, India
| | - Keerrikkattil P Joy
- Department of Zoology, Centre of Advanced Study, Banaras Hindu University, Varanasi 221005, India.
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16
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Di Nardo G, Gilardi G. Human aromatase: perspectives in biochemistry and biotechnology. Biotechnol Appl Biochem 2014; 60:92-101. [PMID: 23586996 DOI: 10.1002/bab.1088] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 12/25/2012] [Indexed: 11/07/2022]
Abstract
Aromatase (CYP19) is involved in steroidogenesis, catalyzing the conversion of androgens into estrogens through a unique reaction that causes the aromatization of the A ring of the steroid. The enzyme is widely distributed and well conserved among species as it plays a crucial role in physiological processes such as control of reproduction and neuroprotection. It has also been a subject of intense research both at the biotechnological level in drug development due to its involvement in estrogen-dependent tumors and at a fundamental biochemical level because there are numerous questions regarding its reaction mechanism. This review will report the great progress made in this area.
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Affiliation(s)
- Giovanna Di Nardo
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
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17
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Duda M, Grzesiak M, Knet M, Knapczyk-Stwora K, Tabarowski Z, Michna A, Slomczynska M. The impact of antiandrogen 2-hydroxyflutamide on the expression of steroidogenic enzymes in cultured porcine ovarian follicles. Mol Biol Rep 2014; 41:4213-22. [PMID: 24584661 PMCID: PMC4066179 DOI: 10.1007/s11033-014-3291-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 02/13/2014] [Indexed: 11/25/2022]
Abstract
We used our model system for agonism and antagonism of the androgen receptor (AR), in which the porcine ovarian follicles were exposed on the excessive concentration of an AR agonist- testosterone (T) or an AR antagonist- 2-hydroxyflutamide (2-Hf) to: (1) analyze the spatiotemporal expression of ovarian 3β-hydroxysteroid dehydrogenase (3β-HSD), cytochrome P450 17α-hydroxylase/c17,20-lyase (P450c17) and cytochrome P450 aromatase (P450arom); (2) to determine the contribution of AR-mediated action during steroidogenesis and (3) to establish some correlations between the onset and expression pattern of the investigated proteins. Whole follicles (6–8 mm in diameter) isolated from mature porcine ovaries have been incubated (for 24 h) in an organ culture system in the presence of T (10−7 M), 2-Hf (1.7 × 10−4 M) or both T and 2-hydroxyflutamide (T+2-Hf, at the same concentrations as when added separately). Thereafter, sections obtained from cultured follicles were processed for main steroidogenic enzymes detection by immunohistochemistry. Moreover, expression of their mRNA and protein was determined by real-time PCR and Western blot analysis. Progesterone, androgens and estradiol concentrations in the culture media were measured by radioimmunoassays (RIA). Our results demonstrated that 2-Hf can influence the steroidogenic activity of porcine follicles in vitro through the blockade of AR. It was shown that follicular 2-Hf treatment brought about dramatic decline in the production of the investigated steroids. What is more the addition of 2-Hf separately caused a negative effect on 3β-HSD and P450c17 mRNA and protein expression by ovarian follicles, while it was without effect on P450arom mRNA level. Quite opposite effect was observed in case of the simultaneous addition of 2-Hf and T. It caused high increase, in both P450arom mRNA and its protein. What was interesting, addition T+2-Hf evoked 3β-HSD and P450c17 increase on mRNA level, but decreased their protein expression. This was against our expectations but the reason for that finding remains undiscovered, intriguing and worth reporting. These results suggest that alike, steroidogenic enzymes activity and their expression is associated with the presence of androgens and AR in the porcine ovary.
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Affiliation(s)
- Malgorzata Duda
- Department of Endocrinology, Institute of Zoology, Jagiellonian University, Gronostajowa 9, 30-387, Cracow, Poland,
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Robic A, Faraut T, Prunier A. Pathways and genes involved in steroid hormone metabolism in male pigs: a review and update. J Steroid Biochem Mol Biol 2014; 140:44-55. [PMID: 24239507 DOI: 10.1016/j.jsbmb.2013.11.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 09/19/2013] [Accepted: 11/04/2013] [Indexed: 10/26/2022]
Abstract
This paper reviews state-of-the-art knowledge on steroid biosynthesis pathways in the pig and provides an updated characterization of the porcine genes involved in these pathways with particular focus on androgens, estrogens, and 16-androstenes. At least 21 different enzymes appear to be involved in these pathways in porcine tissues together with at least five cofactors. Until now, data on several porcine genes were scarce or confusing. We characterized the complete genomic and transcript sequences of the single porcine CYP11B gene. We analyzed the porcine AKR1 gene cluster and identified four AKR1C, one AKR1C like genes and one AKR1E2 gene. We provide evidence that porcine AKR1C genes are not orthologous to human AKR1C. A new nomenclature is thus needed for this gene family in the pig. Thirty-two genes are now described: transcript (30+2 characterized in this study) and genomic (complete: 18+1 and partial: 12+1) sequences are identified. However, despite increasing knowledge on steroid metabolism in the pig, there is still no explanation of why porcine testes can produce androstenone and epiandrosterone, but not dihydrotestosterone (DHT), which is also a reduced steroid.
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Key Words
- 11-K-DHT
- 11-K-Testo
- 11-OH-DHT
- 11-OH-Testo
- 11-OH-Δ4-AD
- 11-keto dihydrotestosterone
- 11-ketotestosterone or 17-Hydroxyandrost-4-ene-3,11-dione
- 11deoxycorticosterone or 21-hydroxyprogesterone (21-hydroxy-4-pregnene-3,20-dione)
- 11β hydroxy-androstenedione or 11β-hydroxyandrost-4-ene-3,17-dione
- 11β-hydroxy dihydrotestosterone
- 11β-hydroxy testosterone or 11β,17β-dihydroxy-4-androsten-3-one
- 17-hydroxy pregnenolone
- 17-hydroxy progesterone
- 17OH- progesterone
- 17OH-pregnenolone
- 17β-estra-1,3,5(10)-triene-3,17-diol
- 17β-hydroxy-5alpha-androst-1-en-3-one
- 19-OH-Testo
- 19-OH-Δ4-AD
- 19-norTesto
- 19-nortestosterone (or nandrolone) or 17β-hydroxyestra-4-en-3-one
- 19β hydroxy-androstenedione or 19β hydroxyandrost-4-ene-3,17-dione
- 19β-hydroxy testosterone or 17β,19-dihydroxyandrost-4-en-3-one
- 20-OH-progesterone
- 20αprogesterone or 4-pregnen-20-α-ol-3-one
- 21 steroid hydroxylase enzyme encoded by porcine CYP21 gene
- 3-hydroxyestra-1,3,5(10)-triene-17-one
- 3α-hydroxy-5α-androstan-17-one
- 4-pregnen-3,20-dione
- 5-pregnen-3β-ol-20-one
- 5-α reductase
- 5α-R
- 5α-Reduction
- 5α-androstan-3,17-diol
- AD
- AKR1C
- Adrenosterone
- Androstadienol
- Androstadienone
- Androstanediol
- Androstenone
- Androsterone
- Boar
- CYP11
- Cytb5
- Cytb5-red
- DHEA
- DHT
- DOC
- EpiA
- Estradiol
- Estrone
- HSD
- Hormones
- P450 aromatase encoded by one of the three porcine CYP19A genes
- P450aro
- P450c11
- P450c17
- P450c21
- P450scc
- Pregnenolone
- Progesterone
- S
- StAR
- Steroidogenesis
- Testosterone
- aa
- amino acid
- androst-4-ene-3,11,17-trione or 11-oxoandrostenedione
- androstanedione or 5α-androstan-3,17-dione
- androstenediol or 5-Androstene-3,17-diol
- androstenedione or 4-Androstene-3,17-dione
- cytochrome P450 side chain cleavage encoded by porcine CYP11A1 gene
- cytochrome b5
- cytochrome b5 reductase
- dehydroepiandrosterone or 3β-hydroxyandrost-5-en-17-one
- dihydrotestosterone or 17β-hydroxy-5α-androstan-3-one
- enzyme encoded by porcine CYP11B gene
- enzyme encoded by porcine CYP17A1 gene
- epiandrosterone or 3β-hydroxy-5α-androstan-17-one
- hydroxysteroid dehydrogenase
- steroidogenic acute regulatory encoded by porcine STAR gene
- sulphate
- Δ 4,16-androstadien-3-ol
- Δ 4,16-androstadien-3-one
- Δ4-AD
- Δ4-androstene -3-one
- Δ5-ADiol
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Affiliation(s)
- Annie Robic
- UMR444, Génétique Cellulaire, INRA, CS 52627, 31326 Castanet Tolosan, France; UMR444, Génétique Cellulaire, Université de Toulouse, INP, ENVT, 31076 Toulouse, France.
| | - Thomas Faraut
- UMR444, Génétique Cellulaire, INRA, CS 52627, 31326 Castanet Tolosan, France; UMR444, Génétique Cellulaire, Université de Toulouse, INP, ENVT, 31076 Toulouse, France.
| | - Armelle Prunier
- UMR1348-PEGASE, INRA, 35590 Saint-Gilles, France; UMR1348-PEGASE, Agrocampus Ouest, 35000 Rennes, France.
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19
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Böhne A, Heule C, Boileau N, Salzburger W. Expression and sequence evolution of aromatase cyp19a1 and other sexual development genes in East African cichlid fishes. Mol Biol Evol 2013; 30:2268-85. [PMID: 23883521 PMCID: PMC3773371 DOI: 10.1093/molbev/mst124] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Sex determination mechanisms are highly variable across teleost fishes and sexual development is often plastic. Nevertheless, downstream factors establishing the two sexes are presumably conserved. Here, we study sequence evolution and gene expression of core genes of sexual development in a prime model system in evolutionary biology, the East African cichlid fishes. Using the available five cichlid genomes, we test for signs of positive selection in 28 genes including duplicates from the teleost whole-genome duplication, and examine the expression of these candidate genes in three cichlid species. We then focus on a particularly striking case, the A- and B-copies of the aromatase cyp19a1, and detect different evolutionary trajectories: cyp19a1A evolved under strong positive selection, whereas cyp19a1B remained conserved at the protein level, yet is subject to regulatory changes at its transcription start sites. Importantly, we find shifts in gene expression in both copies. Cyp19a1 is considered the most conserved ovary-factor in vertebrates, and in all teleosts investigated so far, cyp19a1A and cyp19a1B are expressed in ovaries and the brain, respectively. This is not the case in cichlids, where we find new expression patterns in two derived lineages: the A-copy gained a novel testis-function in the Ectodine lineage, whereas the B-copy is overexpressed in the testis of the speciest-richest cichlid group, the Haplochromini. This suggests that even key factors of sexual development, including the sex steroid pathway, are not conserved in fish, supporting the idea that flexibility in sexual determination and differentiation may be a driving force of speciation.
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Affiliation(s)
- Astrid Böhne
- Zoological Institute, University of Basel, Basel, Switzerland
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20
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Kwon JY, Kim J. Differential expression of two distinct aromatase genes (cyp19a1aandcyp19a1b) during vitellogenesis and gestation in the viviparous black rockfishSebastes schlegelii. Anim Cells Syst (Seoul) 2013. [DOI: 10.1080/19768354.2013.773941] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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21
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Berger T, Conley AJ, Van Klompenberg M, Roser JF, Hovey RC. Increased testicular Sertoli cell population induced by an estrogen receptor antagonist. Mol Cell Endocrinol 2013. [PMID: 23178163 DOI: 10.1016/j.mce.2012.11.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Sertoli cell proliferation is prolonged in neonatal boars treated with the aromatase inhibitor letrozole, but porcine testicular aromatase synthesizes a potent, non-aromatizable androgen, 1-hydroxytestosterone, as well as estradiol. Therefore, experiments were conducted to determine whether the Sertoli cell proliferative response to letrozole is due to a loss of estrogen or a loss of androgen signaling. Littermate boars were treated with letrozole, the estrogen receptor blocker ICI 182,780, or vehicle, from 1 week of age and testes collected at 6.5 weeks. Sertoli cell number was increased 30% by letrozole or ICI 182,780 compared with vehicle. Neither treatment affected testosterone, gonadotropins or prolactin. We conclude that Sertoli cell proliferation in neonatal boars is restricted by the local activation of estrogen receptors. The response to letrozole is apparently not mediated by the novel capacity of the porcine gonadal aromatase for 1-hydroxytestosterone but by estradiol synthesis; therefore, aromatase inhibition may have similar effects on Sertoli cell proliferation in other species.
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Affiliation(s)
- Trish Berger
- Department of Animal Science, University of California, Davis, CA 95616, USA.
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22
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Jeng SR, Pasquier J, Yueh WS, Chen GR, Lee YH, Dufour S, Chang CF. Differential regulation of the expression of cytochrome P450 aromatase, estrogen and androgen receptor subtypes in the brain-pituitary-ovarian axis of the Japanese eel (Anguilla japonica) reveals steroid dependent and independent mechanisms. Gen Comp Endocrinol 2012; 175:163-72. [PMID: 22107840 DOI: 10.1016/j.ygcen.2011.11.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 10/31/2011] [Accepted: 11/04/2011] [Indexed: 11/15/2022]
Abstract
This study aimed at investigating the role of sexual steroids in the regulation of the expression of the single aromatase gene and steroid receptor subtypes in the brain-pituitary-ovarian axis of the Japanese eel. Unlike other teleosts, which possess duplicated genes for aromatase, cyp19a1a and cyp19a1b, expressed in the gonads and in the brain, respectively, eel species possess a single cyp19a1. Phylogenetic analysis indicated that eel brain/gonadal cyp19a1 branches at the basis of both teleost gonadal cyp19a1a and brain cyp19a1b clades. Female eels treated with catfish pituitary homogenate (CPH) to induce sexual maturation showed an increase in the expression of cyp19a1 and aromatase enzymatic activity in the brain and in the ovaries. Treatments with sex steroids (estradiol-17β, E(2) or testosterone, T) revealed that the increase in cyp19a1 expression in the brain may result from E(2)-specific induction. In contrast, the increase in cyp19a1 expression in the ovaries of CPH-treated eels is a result of steroid-independent control, probably from a direct effect of gonadotropins contained in the pituitary extract. Analysis of the expression of estrogen and androgen receptor subtypes, esr-α, esr-β, ar-α and ar-β, in eels treated with CPH or sex steroids revealed differential regulations. In CPH-treated eels, the expression of esr-α and ar-α was significantly increased in the brain, while the expression of ar-α and ar-β was increased in the ovaries. No change was observed in esr-β in any organ. Steroid treatments induced an upregulation by E(2) of esr-α, but not esr-β expression, in the brain, pituitary and ovaries, while no autoregulation by T of its own receptors could be observed. These results reveal both steroid-dependent and -independent mechanisms in the regulation of cyp19a1 and steroid receptor subtype expression in the eel.
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Affiliation(s)
- Shan-Ru Jeng
- Department of Aquaculture, National Kaohsiung Marine University, Kaohsiung 811, Taiwan.
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23
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Diotel N, Le Page Y, Mouriec K, Tong SK, Pellegrini E, Vaillant C, Anglade I, Brion F, Pakdel F, Chung BC, Kah O. Aromatase in the brain of teleost fish: expression, regulation and putative functions. Front Neuroendocrinol 2010; 31:172-92. [PMID: 20116395 DOI: 10.1016/j.yfrne.2010.01.003] [Citation(s) in RCA: 223] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Revised: 01/20/2010] [Accepted: 01/24/2010] [Indexed: 12/25/2022]
Abstract
Unlike that of mammals, the brain of teleost fish exhibits an intense aromatase activity due to the strong expression of one of two aromatase genes (aromatase A or cyp19a1a and aromatase B or cyp19a1b) that arose from a gene duplication event. In situ hybridization, immunohistochemistry and expression of GFP (green fluorescent protein) in transgenic tg(cyp19a1b-GFP) fish demonstrate that aromatase B is only expressed in radial glial cells (RGC) of adult fish. These cells persist throughout life and act as progenitors in the brain of both developing and adult fish. Although aromatase B-positive radial glial cells are most abundant in the preoptic area and the hypothalamus, they are observed throughout the entire central nervous system and spinal cord. In agreement with the fact that brain aromatase activity is correlated to sex steroid levels, the high expression of cyp19a1b is due to an auto-regulatory loop through which estrogens and aromatizable androgens up-regulate aromatase expression. This mechanism involves estrogen receptor binding on an estrogen response element located on the cyp19a1b promoter. Cell specificity is achieved by a mandatory cooperation between estrogen receptors and unidentified glial factors. Given the emerging roles of estrogens in neurogenesis, the unique feature of the adult fish brain suggests that, in addition to classical functions on brain sexual differentiation and sexual behaviour, aromatase expression in radial glial cells could be part of the mechanisms authorizing the maintenance of a high proliferative activity in the brain of fish.
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Affiliation(s)
- Nicolas Diotel
- Neurogenesis And OEstrogens, UMR CNRS 6026, IFR 140, Université de Rennes 1, Rennes, France
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24
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Hong Y, Li H, Yuan YC, Chen S. Sequence-function correlation of aromatase and its interaction with reductase. J Steroid Biochem Mol Biol 2010; 118:203-6. [PMID: 19944754 PMCID: PMC2836254 DOI: 10.1016/j.jsbmb.2009.11.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Revised: 11/19/2009] [Accepted: 11/19/2009] [Indexed: 11/26/2022]
Abstract
Aromatase is an enzyme required for the conversion of androgens to estrogens. Estrogens are female sex hormones involved in the development and growth of breast tumors. It has been of significant interest to investigate the structure-function relationship of aromatase since its inhibitors have shown great promise in fighting breast cancer. Aromatase belongs to the cytochrome P450 family, and forms an electron-transfer complex with its partner, NADPH-cytochrome P450 reductase (CPR), during the aromatization reaction. Aromatase is found to be widely expressed in vertebrates with unique substrates androstenedione and testosterone, but with various catalytic capacities reflecting species differences in K(m), Vmax, etc. This report will summarize current progress in sequence-function correlation analysis of the aromatase protein family and molecular characterization of the interaction between aromatase and CPR. These studies may lead to a novel field for the development of new inhibitors which interfere with the interaction between aromatase and CPR in order to inhibit the aromatization reaction.
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Affiliation(s)
- Yanyan Hong
- Division of Tumor Cell Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
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25
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Androgens and estradiol-17beta production by porcine uterine cells: In vitro study. Theriogenology 2010; 73:232-41. [PMID: 19880166 DOI: 10.1016/j.theriogenology.2009.09.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 09/14/2009] [Accepted: 09/14/2009] [Indexed: 11/22/2022]
Abstract
Porcine (Sus scrofa domestica) uterine slices harvested during both early pregnancy and luteolysis produce steroid hormones. The aim of the present study was to determine (1) which porcine separated uterine cells secrete androgens: androstenedione (A(4)) and testosterone (T), and estradiol-17beta (E(2)) in culture; (2) if the production of A(4), T and E(2) in the uterine cells is regulated by P4 and OT; (3) if uterine tissues expressed cytochrome P450arom gene (CYP19). Uteri were collected on Days 14 to 16 of early pregnancy and the estrous cycle. Enzymatically separated epithelial cells, stromal cells, and myocytes were cultured in vitro for 2, 6, and 12h with control medium, progesterone (P(4); 10(-5) M), oxytocin (OT; 10(-7) M), and both hormones (P(4)+OT). The studied cells secreted A(4), T, and E(2) in vitro. Progesterone served as a substrate for steroid synthesis in the uterine cells. Isolated uterine cells, cultured separately, contributed in equal portion to the basal production of androgens (A(4) and T) during both early pregnancy and luteolysis. In pregnant pigs, the epithelial and stromal cells were rich sources of E(2) compared with myocytes. Myocytes produced E(2) mainly during luteolysis. Pregnant porcine endometrium and myometrium expressed the gene CYP19, which encodes for P450 aromatase, a steroidogenic enzyme. The results indicate an active steroidogenic pathway in porcine uterine cells. The epithelial cells, stromal cells, and myocytes participate in steroid production as an alternative source for their action in pigs.
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26
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Do Rego JL, Seong JY, Burel D, Leprince J, Luu-The V, Tsutsui K, Tonon MC, Pelletier G, Vaudry H. Neurosteroid biosynthesis: enzymatic pathways and neuroendocrine regulation by neurotransmitters and neuropeptides. Front Neuroendocrinol 2009; 30:259-301. [PMID: 19505496 DOI: 10.1016/j.yfrne.2009.05.006] [Citation(s) in RCA: 277] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Revised: 05/12/2009] [Accepted: 05/21/2009] [Indexed: 01/09/2023]
Abstract
Neuroactive steroids synthesized in neuronal tissue, referred to as neurosteroids, are implicated in proliferation, differentiation, activity and survival of nerve cells. Neurosteroids are also involved in the control of a number of behavioral, neuroendocrine and metabolic processes such as regulation of food intake, locomotor activity, sexual activity, aggressiveness, anxiety, depression, body temperature and blood pressure. In this article, we summarize the current knowledge regarding the existence, neuroanatomical distribution and biological activity of the enzymes responsible for the biosynthesis of neurosteroids in the brain of vertebrates, and we review the neuronal mechanisms that control the activity of these enzymes. The observation that the activity of key steroidogenic enzymes is finely tuned by various neurotransmitters and neuropeptides strongly suggests that some of the central effects of these neuromodulators may be mediated via the regulation of neurosteroid production.
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Affiliation(s)
- Jean Luc Do Rego
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 413, 76821 Mont-Saint-Aignan, France
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27
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Conley AJ, Corbin CJ, Hughes AL. Adaptive evolution of mammalian aromatases: lessons from Suiformes. ACTA ACUST UNITED AC 2009; 311:346-57. [PMID: 18381772 DOI: 10.1002/jez.451] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Estrogen synthesis evolved in chordates to control reproduction. The terminal enzyme in the cascade directly responsible for estrogen synthesis is aromatase cytochrome P450 (P450arom) encoded by the CYP19 gene. Mammals typically have a single CYP19 gene but pigs, peccaries and other Suiformes have two or more resulting from duplication in a common ancestor. Duplication of CYP genes in the steroid synthetic cascade has occurred for only one other enzyme, also terminal, 11beta-hydroxylase P450 (P450c11). P450arom and P450c11 share common substrates and even physiological functions as possible remnants from a common P450 progenitor, perhaps an ancestral P450arom, which is supported by phylogenetic analysis. Conserved tissue-specific expression patterns of P450arom paralogs in placenta and gonads of pigs and peccaries suggest how functional adaptation may have proceeded divergently and influenced adopted reproductive strategies including ovulation rate and litter size. Data suggest that the porcine placental paralog evolved catalytically to protect female conceptuses from testosterone produced by male siblings; the gonadal paralog to synthesize a novel, nonaromatizable testosterone metabolite (1OH-testosterone) that may increase ovulation rate. This would represent a coevolution facilitating litter bearing as pigs diverged from peccaries. Evidence of convergence between the peccary CYP19 genes and lower tissue expression may therefore represent initiation of loss of the functional paralogs. Studies on the Suiforme aromatases provide insights into the evolution of the steroidogenic cascade and metabolic pathways in general, how it translates into physiological adaptations (altered reproductive strategies for instance), and how duplicated genes become stabilized or disappear from genomes.
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Affiliation(s)
- A J Conley
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Abstract
Aromatase is an estrogen synthetase. Estrogens are female sex hormones involved in the development and growth of breast tumors. Elucidation of the structure-function relationship of aromatase has been of significant interest since its inhibitors have shown great promise in fighting breast cancer. Aromatase belongs to the cytochrome P450 family and forms an electron-transfer complex with its partner, NADPH-cytochrome P450 reductase. Because of the membrane-bound character and heme-binding instability, no crystal structure of aromatase has been reported so far. Much remains to be investigated, including the 3-dimensional structure of aromatase, interaction between aromatase and reductase, catalytic mechanism of estrogen synthesis by aromatase, and the binding mechanism of aromatase inhibitors. This review presents current knowledge about structural and functional characteristics of aromatase to address unsolved mysteries about this enzyme.
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Affiliation(s)
- Yanyan Hong
- Department of Surgical Research, Beckman Research Institute of City of Hope, Duarte, California 91010, USA
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Effects of transferrin on aromatase activity in porcine granulosa cells in vitro. Folia Histochem Cytobiol 2009; 46:423-8. [PMID: 19141392 DOI: 10.2478/v10042-008-0070-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Proliferating cells have an absolute requirement for iron, which is delivered by transferrin with subsequent intracellular transport via the transferrin receptor. Recent studies have reported that transferrin plays a crucial role in the local regulation of ovarian function, apart from its iron-binding characteristic. Therefore, the present study was undertaken to explore the possible role of transferrin in porcine granulosa cells function by examining its influence on aromatase activity, the most important indicator of follicular cell differentiation. In the first series of studies, pig granulosa cells isolated from small, immature follicles were cultured in the presence of transferrin alone (10 microg/ml or 100 microg/ml) or with the addition of FSH (100ng/ml). The second series of studies was undertaken to determine transferrin-stimulated granulosa cells ability to aromatize exogenous testosterone (1x10(-7)M). One hour after the establishment of cultures an aromatase inhibitor CGS16949A was added to test its influence on estradiol production. After 48 hours, cultures were terminated and cells were processed for immunocytochemical staining of aromatase. Media were frozen for further estradiol level analysis. Positive immunostaining for aromatase was found in all granulosa cell cultures. The intensity of immunostaining was always stronger in cultures supplemented with FSH whereas the addition of transferrin had no effect. Granulosa cells in vitro synthesized the highest amount of estradiol after the addition of FSH and exogenous testosterone as measured radioimmunologically. Concomitant treatment with FSH and transferrin caused an inhibition of FSH-stimulated aromatase activity. The production of estradiol also declined in the presence of FSH, testosterone and transferrin. This study demonstrates that transferrin had a dose-dependent inhibitory effect on FSH-stimulated aromatase activity, which was confirmed by radioimmunoassay. Our results indicate that transferrin may be an important factor in the regulation of granulosa cell diferentiation.
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Klaunig JE, Babich MA, Baetcke KP, Cook JC, Corton JC, David RM, DeLuca JG, Lai DY, McKee RH, Peters JM, Roberts RA, Fenner-Crisp PA. PPARα Agonist-Induced Rodent Tumors: Modes of Action and Human Relevance. Crit Rev Toxicol 2008; 33:655-780. [PMID: 14727734 DOI: 10.1080/713608372] [Citation(s) in RCA: 433] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Widely varied chemicals--including certain herbicides, plasticizers, drugs, and natural products--induce peroxisome proliferation in rodent liver and other tissues. This phenomenon is characterized by increases in the volume density and fatty acid oxidation of these organelles, which contain hydrogen peroxide and fatty acid oxidation systems important in lipid metabolism. Research showing that some peroxisome proliferating chemicals are nongenotoxic animal carcinogens stimulated interest in developing mode of action (MOA) information to understand and explain the human relevance of animal tumors associated with these chemicals. Studies have demonstrated that a nuclear hormone receptor implicated in energy homeostasis, designated peroxisome proliferator-activated receptor alpha (PPARalpha), is an obligatory factor in peroxisome proliferation in rodent hepatocytes. This report provides an in-depth analysis of the state of the science on several topics critical to evaluating the relationship between the MOA for PPARalpha agonists and the human relevance of related animal tumors. Topics include a review of existing tumor bioassay data, data from animal and human sources relating to the MOA for PPARalpha agonists in several different tissues, and case studies on the potential human relevance of the animal MOA data. The summary of existing bioassay data discloses substantial species differences in response to peroxisome proliferators in vivo, with rodents more responsive than primates. Among the rat and mouse strains tested, both males and females develop tumors in response to exposure to a wide range of chemicals including DEHP and other phthalates, chlorinated paraffins, chlorinated solvents such as trichloroethylene and perchloroethylene, and certain pesticides and hypolipidemic pharmaceuticals. MOA data from three different rodent tissues--rat and mouse liver, rat pancreas, and rat testis--lead to several different postulated MOAs, some beginning with PPARalpha activation as a causal first step. For example, studies in rodent liver identified seven "key events," including three "causal events"--activation of PPARalpha, perturbation of cell proliferation and apoptosis, and selective clonal expansion--and a series of associative events involving peroxisome proliferation, hepatocyte oxidative stress, and Kupffer-cell-mediated events. Similar in-depth analysis for rat Leydig-cell tumors (LCTs) posits one MOA that begins with PPARalpha activation in the liver, but two possible pathways, one secondary to liver induction and the other direct inhibition of testicular testosterone biosynthesis. For this tumor, both proposed pathways involve changes in the metabolism and quantity of related hormones and hormone precursors. Key events in the postulated MOA for the third tumor type, pancreatic acinar-cell tumors (PACTs) in rats, also begin with PPARalpha activation in the liver, followed by changes in bile synthesis and composition. Using the new human relevance framework (HRF) (see companion article), case studies involving PPARalpha-related tumors in each of these three tissues produced a range of outcomes, depending partly on the quality and quantity of MOA data available from laboratory animals and related information from human data sources.
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Affiliation(s)
- James E Klaunig
- Indiana University School of Medicine, Indianapolis, IN, USA
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31
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Wynne RD, Maas S, Saldanha CJ. Molecular characterization of the injury-induced aromatase transcript in the adult zebra finch brain. J Neurochem 2008; 105:1613-24. [PMID: 18312309 DOI: 10.1111/j.1471-4159.2008.05256.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the zebra finch (Taeniopygia guttata), the aromatase gene is transcribed from one of two promoters resulting in two transcripts constitutively expressed in brain or ovary. These transcripts differ only in Exon 1 which lies in the 5' un-translated region (UTR). An inducible form of aromatase is expressed following brain injury in glia. Towards characterizing this transcript, we (a) examined the up-regulation of amplicons within the aromatase transcript using quantitative PCR (qPCR), (b) performed 5' and 3' rapid amplification of cDNA ends (RACE) on injured brain RNA and (c) sequenced the injury-induced aromatase transcript. qPCR suggested that inducible aromatase may contain a novel 3'UTR. However, neither 3' nor 5' RACE revealed novel UTRs in the injured telencephalon. We then sequenced aromatase from injured entopallium, a region that lacks detectable constitutive aromatase. Inducible aromatase was identical in sequence to the known neural aromatase transcript. These data suggest that injury-induced aromatase differs from ovarian, but is indistinguishable from neuronal aromatase. We suggest that an injury-specific signal in glia may modulate aromatase transcription. Alternatively, injury-induced aromatase transcription may be silenced under constitutive conditions. To the best of our knowledge, this is the first report that documents the sequence of inducible aromatase in any vertebrate.
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Affiliation(s)
- Ryan D Wynne
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania 18015, USA
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Carreau S, Silandre D, Bourguiba S, Hamden K, Said L, Lambard S, Galeraud-Denis I, Delalande C. Estrogens and male reproduction: a new concept. Braz J Med Biol Res 2008; 40:761-8. [PMID: 17581673 DOI: 10.1590/s0100-879x2007000600003] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2007] [Accepted: 05/04/2007] [Indexed: 01/30/2023] Open
Abstract
The mammalian testis serves two main functions: production of spermatozoa and synthesis of steroids; among them estrogens are the end products obtained from the irreversible transformation of androgens by a microsomal enzymatic complex named aromatase. The aromatase is encoded by a single gene (cyp19) in humans which contains 18 exons, 9 of them being translated. In rats, the aromatase activity is mainly located in Sertoli cells of immature rats and then in Leydig cells of adult rats. We have demonstrated that germ cells represent an important source of estrogens: the amount of P450arom transcript is 3-fold higher in pachytene spermatocytes compared to gonocytes or round spermatids; conversely, aromatase activity is more intense in haploid cells. Male germ cells of mice, bank voles, bears, and monkeys express aromatase. In humans, we have shown the presence of a biologically active aromatase and of estrogen receptors (alpha and ss) in ejaculated spermatozoa and in immature germ cells in addition to Leydig cells. Moreover, we have demonstrated that the amount of P450arom transcripts is 30% lower in immotile than in motile spermatozoa. Alterations of spermatogenesis in terms of number and motility of spermatozoa have been described in men genetically deficient in aromatase. These last observations, together with our data showing a significant decrease of aromatase in immotile spermatozoa, suggest that aromatase could be involved in the acquisition of sperm motility. Thus, taking into account the widespread localization of aromatase and estrogen receptors in testicular cells, it is obvious that, besides gonadotrophins and androgens, estrogens produced locally should be considered to be physiologically relevant hormones involved in the regulation of spermatogenesis and spermiogenesis.
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Affiliation(s)
- S Carreau
- Department of Biochemistry, University of Caen, Caen, France.
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Raeside JI, Christie HL. The presence of 19-norandrostenedione and its sulphate form in yolk-sac fluid of the early equine conceptus. J Steroid Biochem Mol Biol 2008; 108:149-54. [PMID: 17980578 DOI: 10.1016/j.jsbmb.2007.09.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2007] [Accepted: 09/24/2007] [Indexed: 10/22/2022]
Abstract
C(18) neutral steroid formation by cytochrome P450 aromatase has been recorded for several equine and porcine tissues. High activity of P450 aromatase is reflected in the quantities of estrogens in yolk-sac (y-s) fluid of early equine conceptuses. In a previous study of y-s fluid we detected large amounts of androgens by radioimmunoassay (RIA), using an antiserum for androstenedione (A(4)). Here, we report that RIA, following chromatography, gave tentative identification of the major peak as norandrostenedione (19-norA) not as A(4). Furthermore, even greater quantities of 19-norA seemed to be present in y-s fluid as a sulphoconjugate, as noted from extraction, solvolysis, HPLC, followed by RIA. Confirmation of these unusual findings was attained after further purification with two HPLC systems and definitive identification by LC-MS with an authentic standard of 19-norA. Initial extraction of the steroid sulphate as a methylene-blue complex also yielded 19-norA suggesting that the 3-enol form had enabled sulphoconjugation. The biological significance of retention mainly as a sulphate is not known; however, the large amounts of 19-norA found in the fluid accords well with reports on the catalytic activity shown in vitro by the blastocyst isozyme of P450 aromatase in the pig and horse.
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Affiliation(s)
- J I Raeside
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada.
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Corbin CJ, Hughes AL, Heffelfinger JR, Berger T, Waltzek TB, Roser JF, Santos TC, Miglino MA, Oliveira MF, Braga FC, Meirelles FV, Conley AJ. Evolution of suiform aromatases: ancestral duplication with conservation of tissue-specific expression in the collared peccary (Pecari tayassu). J Mol Evol 2007; 65:403-12. [PMID: 17912474 DOI: 10.1007/s00239-007-9021-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2006] [Revised: 04/24/2007] [Accepted: 07/31/2007] [Indexed: 11/25/2022]
Abstract
Aromatase cytochrome P450 (P450arom), the enzyme that catalyzes estrogen synthesis, is required for successful reproduction and is encoded by a single copy gene (CYP19) in most mammals. However, pigs and their distant suiform relatives the peccaries experienced CYP19 duplication. Here, the evolutionary origin of CYP19 duplication, and the evolution of the gene paralogs, was explored further in collared peccaries (Pecari tayassu). Exons IV and V, and the intervening intron, representing duplicated CYP19 genes, were cloned and sequenced from collared peccary, pig, and hippopotamus. Sequence alignment and analysis identified a gene conversion in collared peccary with a breakpoint 102 base pairs (bp) upstream of exon V. Phylogenetic analyses of nucleotide and amino acid sequence upstream of the breakpoint supported a tree in which one peccary sequence was orthologous with the porcine gonadal gene. Cloning and sequencing of tissue transcripts, using reverse-transcriptase polymerase chain reaction techniques (RT-PCR), confirmed that the gonadal ortholog was expressed in collared peccary testis. Orthology of the other genomic sequence with the porcine placental gene was not resolved, but its placenta-specific expression in collared peccary was confirmed by similar transcript analysis. Immunoblot and enzyme activity in collared peccary testes demonstrated much lower levels of P450arom than in pig testis. Collared peccary placental P450arom expression also seemed much lower than pigs. Thus, suiform CYP19 genes arose from an ancestral duplication that has maintained gonad- and placenta-specific expression, but at lower levels in peccaries than pigs, perhaps facilitating the emergence of different reproductive strategies as Suiformes diverged and evolved.
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Affiliation(s)
- C J Corbin
- Department of Population Health and Reproduction, University of California, Davis, CA, USA
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35
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Toffolo V, Belvedere P, Colombo L, Dalla Valle L. Tissue-specific transcriptional initiation of the CYP19 genes in rainbow trout, with analysis of splicing patterns and promoter sequences. Gen Comp Endocrinol 2007; 153:311-9. [PMID: 17400217 DOI: 10.1016/j.ygcen.2007.02.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 02/09/2007] [Accepted: 02/13/2007] [Indexed: 11/27/2022]
Abstract
The rainbow trout (Oncorhynchus mykiss Walbaum) genome contains three separate CYP19 genes for distinct isoforms of cytochrome P450arom: CYP19A encoding the prevalently ovarian isoform P450aromA, and CYP19B-I and II, encoding forms I and II of the mainly cerebral variant P450aromB. RNA Ligase-Mediated 5'-Rapid Amplification of cDNA Ends analysis was used to determine the 5'-untranslated terminal regions (5'-UTRs) of the corresponding mRNAs, which are actually all expressed in the ovary, brain and gills. CYP19A is transcribed at different transcription start sites (TSSs) in each tissue, the most distal TSS being found in the brain, the intermediate one in the gills, and the proximal one in the ovary. CYP19B-I also displays tissue-specific TSSs, but transcripts undergo three distinct splicing patterns: the same pattern as previously reported for the brain and occurring also in the gills, and two novel patterns, established in the ovary and brain, which include two cryptic 3'-splice sites in intron 1, leading to the inclusion of intronic sequences of 92/94 and 66 b in the 5'-UTRs. Lastly, the CYP19B-II transcript in the ovary shows the same splicing pattern previously described for the brain. A PCR-based gene walking strategy was used to explore the promoter regions of the rainbow trout CYP19 genes, which were found to contain potential binding sites for a variety of transcription factors.
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Affiliation(s)
- Vania Toffolo
- Comparative Endocrinology Laboratory, Department of Biology, University of Padova, Via U. Bassi 58/B, 35131 Padova, Italy
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Forlano PM, Schlinger BA, Bass AH. Brain aromatase: new lessons from non-mammalian model systems. Front Neuroendocrinol 2006; 27:247-74. [PMID: 16828853 DOI: 10.1016/j.yfrne.2006.05.002] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2006] [Revised: 05/11/2006] [Accepted: 05/16/2006] [Indexed: 01/29/2023]
Abstract
This review highlights recent studies of the anatomical and functional implications of brain aromatase (estrogen synthase) expression in two vertebrate lineages, teleost fishes and songbirds, that show remarkably high levels of adult brain aromatase activity, protein and gene expression compared to other vertebrate groups. Teleosts and birds have proven to be important neuroethological models for investigating how local estrogen synthesis leads to changes in neural phenotypes that translate into behavior. Region-specific patterns of aromatase expression, and thus estrogen synthesis, include the vocal and auditory circuits that figure prominently into the life history adaptations of vocalizing teleosts and songbirds. Thus, by targeting, for example, vocal motor circuits without inappropriate steroid exposure to other steroid-dependent circuits, such as those involved in either copulatory or spawning behaviors, the neuroendocrine system can achieve temporal and spatial specificity in its modulation of neural circuits that lead to the performance of any one behavior.
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Affiliation(s)
- Paul M Forlano
- Vollum Institute, Oregon Health and Science University, Portland, OR 97239, USA.
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Kanda H, Okubo T, Omori N, Niihara H, Matsumoto N, Yamada K, Yoshimoto S, Ito M, Yamashita S, Shiba T, Takamatsu N. Transcriptional regulation of the rainbow trout CYP19a gene by FTZ-F1 homologue. J Steroid Biochem Mol Biol 2006; 99:85-92. [PMID: 16621513 DOI: 10.1016/j.jsbmb.2005.12.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2005] [Accepted: 12/06/2005] [Indexed: 11/27/2022]
Abstract
In rainbow trout, there are at least two CYP19 genes (CYP19a and CYP19b). They encode distinct P450arom isozymes that are differentially expressed in the ovary and brain. To understand the transcriptional regulation of the rainbow trout CYP19a (rtCYP19a) gene in the ovary, we isolated its 5'-flanking region. The presence of potential FTZ-F1-binding sites prompted us to isolate the cDNA encoding a rainbow trout FTZ-F1 homologue (rtFTZ-F1) and analyze its effect on the rtCYP19a gene transcriptional activity. RT-PCR analysis showed overlapping expression of the rtCYP19a and rtFTZ-F1 genes in the ovary. Transient transfection studies in Chinese hamster ovary-derived CHO-K1 cells revealed that the region from -247 to -105, which contains three potential FTZ-F1-binding sites, was required for rtFTZ-F1-mediated transcriptional activation of the rtCYP19a gene. Among the three potential binding sites, the two from -150 to -142 and from -118 to -110 showed strong affinities for rtFTZ-F1 in gel shift assays, and base substitutions in either site almost abolished the transcriptional activation by rtFTZ-F1. Taken together, these results demonstrate that rtFTZ-F1 plays an important role in the transcriptional regulation of the rtCYP19a gene in the ovary.
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Affiliation(s)
- Hiromi Kanda
- Department of Biosciences, School of Science, Kitasato University, Sagamihara, Kanagawa 228-8555, Japan
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van Nes S, Moe M, Andersen Ø. Molecular characterization and expression of twocyp19 (P450 aromatase) genes in embryos, larvae, and adults of Atlantic halibut (Hippoglossus hippoglossus). Mol Reprod Dev 2005; 72:437-49. [DOI: 10.1002/mrd.20373] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Strobl-Mazzulla PH, Moncaut NP, López GC, Miranda LA, Canario AVM, Somoza GM. Brain aromatase from pejerrey fish (Odontesthes bonariensis): cDNA cloning, tissue expression, and immunohistochemical localization. Gen Comp Endocrinol 2005; 143:21-32. [PMID: 15993101 DOI: 10.1016/j.ygcen.2005.02.026] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2004] [Revised: 02/01/2005] [Accepted: 02/21/2005] [Indexed: 11/24/2022]
Abstract
The brain-type aromatase (CYP19A2) cDNA from pejerrey Odontesthes bonariensis was characterized. Its sequence differs from the ovarian-derived aromatase (CYP19A1) previously reported for the same species. The cDNA is 2305bp in length and the deduced protein comprises 501 amino-acids. The percentage of identity was higher when compared to other brain-derived aromatase proteins (85-63%) and lower with ovarian-derived aromatases (64-57%). Pejerrey aromatases share 61% of identity. The tissue expression analysis showed that CYP19A2 was expressed in the kidney, brain, and pituitary gland of both sexes and also in the ovary, but not in the eye, spleen, liver, gill, and testis. Semi-quantitative RT-PCR analysis of different brain areas revealed that CYP19A2 was expressed significantly higher in anterior male brain areas than in the corresponding female areas, and also when compared to posterior brain areas from both sexes. An immunological analysis using a polyclonal anti-teleost aromatase showed immunoreactive aromatase cells bordering the telencephalic ventricle and a strong signal in the ependymal cells of the preoptic area and the hypothalamus. In the optic tectum immunoreactive aromatase cells were labeled in the ventral wall and in the ependymal layer of the third and fourth ventricle with lateral projections. In the pituitary gland immunoreactive aromatase cells could be found in the rostral and proximal pars distalis. In this gland, aromatase fibers were also detected in different areas; many of them concentrated around blood vessels.
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Affiliation(s)
- Pablo H Strobl-Mazzulla
- Laboratorio de Ictiofisiología y Acuicultura, Instituto de Investigaciones Biotecnológicas/Instituto Tecnológico de Chascomús (CONICET-UNSAM), C.C. 164, (B7130IWA) Chascomús, Provincia de Buenos Aires, Argentina
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Chang X, Kobayashi T, Senthilkumaran B, Kobayashi-Kajura H, Sudhakumari CC, Nagahama Y. Two types of aromatase with different encoding genes, tissue distribution and developmental expression in Nile tilapia (Oreochromis niloticus). Gen Comp Endocrinol 2005; 141:101-15. [PMID: 15748711 DOI: 10.1016/j.ygcen.2004.11.020] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2004] [Revised: 06/30/2004] [Accepted: 11/11/2004] [Indexed: 12/11/2022]
Abstract
We isolated a novel type of aromatase cDNA from a Nile tilapia (Oreochromis niloticus) ovary cDNA library. Because this aromatase is phylogenetically related to brain aromatase (CYP19b) of goldfish, zebrafish and sea bass, we named it tilapia CYP19b (tCYP19b). tCYP19b encodes a protein that is predicted to consist of 495 residues and have 63.8% homology with the aromatase (tCYP19a) we previously isolated from the same source. In vitro transient transfection of cultured COS7 cells demonstrated that tCYP19b codes a functional protein to catalyze estrogen production from an androgen substrate. RT-PCR and Northern hybridization analysis showed that tCYP19b was expressed at a high level in the brain and at a low level in a wide variety of other tissues, whereas tCYP19a was mainly present in the ovary and its level significantly increased during the vitellogenic stage. RT-PCR also detected tCYP19b expression in brain and gonad tissues of both female and male tilapia during sex differentiation, but tCYP19a was only found in the ovary of the fry at that period. These results suggest that tCYP19a plays a key role in sex differentiation and ovarian development. We also isolated genes of two tilapia aromatases. Based on the location of the transcription initiation site, we predicted that there is one promoter for tCYP19a and three promoters for tCYP19b. Although the two aromatase isoforms have similar gene structures in the coding region, we found that the binding regions of SF-1/Ad4 BP region, WT1-KTS and SRY, which are sex-determining factors in mammals, are present in the 5' flank region of tCYP19a but not tCYP19b. A similar situation is present in promoters of zebrafish and goldfish aromatase isoforms. This data indicates that CYP19a plays a decisive role in sex differentiation of those species. The unique presence of the ERE motif in the tCYP19b promoter and the high expression of tCYP19b in the brain support that CYP19b is mainly involved in estrogen-mediated neural estrogen synthesis.
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Affiliation(s)
- Xiaotian Chang
- Department of Reproductive Biology, National Institute for Basic Biology, 444 Okazaki, Japan.
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Dalla Valle L, Toffolo V, Vianello S, Ikuo H, Takashi A, Belvedere P, Colombo L. Genomic organization of the CYP19b genes in the rainbow trout (Oncorhynchus mykiss Walbaum). J Steroid Biochem Mol Biol 2005; 94:49-55. [PMID: 15862949 DOI: 10.1016/j.jsbmb.2005.01.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We report the occurrence of two CYP19b genes, namely CYP19b-I and CYP19b-II, encoding forms I and II of cytochrome P450aromB, the prevalently cerebral variant of aromatase in fish, in the nuclear genome of the rainbow trout. The CYP19b-I gene is 7.6 kbp-long, more than double the size of the known fish CYP19a and b genes, owing to the presence of three introns (1, 4 and 5) that enclose repeated sequences and are longer than 1 kbp. Unlike the CYP19a genes, but similarly to the CYP19b gene of the Nile tilapia, it contains 10, and not 9, exons, including an untranslated exon 1 (83 bp), as found also in the 5' non-coding region of mammalian CYP19 genes. The 5'-UTR is composed by exon 1 and the first 41 bp of exon 2 (150 bp), whose coding region covers the first 36 amino acid residues that incorporate the transmembrane domain. The CYP19b-II gene is only 2.5 kbp-long, because it contains only one intron, corresponding to the third intron of CYP19b-I, and lacks also its first two exons. Thus, it encodes for a presumably soluble protein. Apart from this difference, the rest of the coding region is virtually the same as that of the CYP19b-I gene. The 5'-UTR corresponds in part to the 3'-end (132 bp) of the second intron of the CYP19b-I gene, while the remaining portion (208 bp) bears no homology. CYP19b-II could be regarded as a pseudogene of the CYP19b-I gene, though it is unclear whether it is a processed or a duplicated pseudogene. Moreover, since it is transcriptionally active, it may retain a functional role for the overall brain aromatase activity in the rainbow trout.
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Affiliation(s)
- L Dalla Valle
- Comparative Endocrinology Laboratory, Department of Biology, University of Padova, Via U. Bassi 58/B, 35131 Padova, Italy.
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Wilson JY, McArthur AG, Stegeman JJ. Characterization of a cetacean aromatase (CYP19) and the phylogeny and functional conservation of vertebrate aromatase. Gen Comp Endocrinol 2005; 140:74-83. [PMID: 15596073 DOI: 10.1016/j.ygcen.2004.10.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2004] [Revised: 09/29/2004] [Accepted: 10/12/2004] [Indexed: 11/17/2022]
Abstract
Aromatase (cytochrome P450 19, CYP19, P450arom) is the enzyme responsible for the production of estrogens, hormones critical for development and reproduction. Aromatase was sequenced from a white-sided dolphin (Lagenorhynchus acutus) ovary, transiently transfected into HEK 293 cells, and the expressed protein was characterized for aromatase activity in the presence of androstenedione and testosterone and after exposure to the aromatase inhibitor letrazole. The Kms for androstenedione and testosterone were 63.5 and 75 nM, respectively, values that are very similar to those reported for other mammalian aromatases. A Bayesian phylogenetic analysis of the vertebrate aromatases was performed on the amino acid sequences of aromatases from fish, amphibians, reptiles, birds, and mammals. Based on known species phylogeny, the cetacean aromatase showed an expected grouping with artiodactyls (cow, sheep, and goat). An analysis of functional divergence showed strong conservation of aromatase across the entire protein, which indicates that the observed sequence divergence is functionally neutral.
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Affiliation(s)
- Joanna Y Wilson
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
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Abstract
Background Joining a model for the molecular evolution of a protein family to the paleontological and geological records (geobiology), and then to the chemical structures of substrates, products, and protein folds, is emerging as a broad strategy for generating hypotheses concerning function in a post-genomic world. This strategy expands systems biology to a planetary context, necessary for a notion of fitness to underlie (as it must) any discussion of function within a biomolecular system. Results Here, we report an example of such an expansion, where tools from planetary biology were used to analyze three genes from the pig Sus scrofa that encode cytochrome P450 aromatases–enzymes that convert androgens into estrogens. The evolutionary history of the vertebrate aromatase gene family was reconstructed. Transition redundant exchange silent substitution metrics were used to interpolate dates for the divergence of family members, the paleontological record was consulted to identify changes in physiology that correlated in time with the change in molecular behavior, and new aromatase sequences from peccary were obtained. Metrics that detect changing function in proteins were then applied, including KA/KS values and those that exploit structural biology. These identified specific amino acid replacements that were associated with changing substrate and product specificity during the time of presumed adaptive change. The combined analysis suggests that aromatase paralogs arose in pigs as a result of selection for Suoidea with larger litters than their ancestors, and permitted the Suoidea to survive the global climatic trauma that began in the Eocene. Conclusions This combination of bioinformatics analysis, molecular evolution, paleontology, cladistics, global climatology, structural biology, and organic chemistry serves as a paradigm in planetary biology. As the geological, paleontological, and genomic records improve, this approach should become widely useful to make systems biology statements about high-level function for biomolecular systems.
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Corbin CJ, Mapes SM, Marcos J, Shackleton CH, Morrow D, Safe S, Wise T, Ford JJ, Conley AJ. Paralogues of porcine aromatase cytochrome P450: a novel hydroxylase activity is associated with the survival of a duplicated gene. Endocrinology 2004; 145:2157-64. [PMID: 14962994 DOI: 10.1210/en.2003-1595] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The gonadal and placental paralogues of porcine aromatase cytochrome P450 (P450arom) were examined for novel catalytic properties to shed light on the evolutionary survival of duplicated copies of an enzyme critical to reproduction. Recombinant gonadal P450arom catalyzed the formation of a novel metabolite from testosterone, identified by gas chromatography/mass spectrometry and biochemical analyses as 1 beta-hydroxytestosterone (1 beta OH-T), in almost equal proportion to 17beta-estradiol (E(2)). This activity was absent in reactions with the porcine placental paralogue (or other orthologues) of P450arom and was minimal with androstenedione. Incubations with both porcine enzymes and with bovine and human P450arom demonstrated that 1 beta OH-T was not aromatizable, and 1 beta OH-T activated the androgen receptor of prostate cancer cells in vitro. Porcine testicular and follicular granulosa tissues synthesized 1 beta OH-T, which was also detected in testicular venous plasma. These results constitute the first of identification of a novel, perhaps potent, nonaromatizable metabolite of testosterone, whose synthesis (paradoxically) can be definitively ascribed to the activity of the gonadal paralogue of porcine P450arom. It probably represents an evolutionary gain of function associated with fixation and the survival of the genes after CYP19 duplication. Novel activities and adaptive functions may exist among other duplicated vertebrate aromatases.
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Affiliation(s)
- C Jo Corbin
- Department of Population Health and Reproduction, University of California School of Veterinary Medicine, Davis, California 95616, USA
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Jo Corbin C, Mapes SM, Lee YM, Conley AJ. Structural and functional differences among purified recombinant mammalian aromatases: glycosylation, N-terminal sequence and kinetic analysis of human, bovine and the porcine placental and gonadal isozymes. Mol Cell Endocrinol 2003; 206:147-57. [PMID: 12943997 DOI: 10.1016/s0303-7207(02)00422-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Recombinant porcine gonadal and placental, and the human and bovine, isozymes of aromatase cytochrome P450 (P450arom) were over-expressed in insect cells, purified and quantified by difference spectroscopy. Human and bovine P450arom exhibited greater apparent molecular size than either porcine isozyme prompting an examination of N-linked glycosylation and amino-terminal peptide sequence. Comparisons of substrate affinities and turnover were also made. In contrast to human and bovine P450arom which are N-linked glycoproteins, neither isozyme of porcine P450arom is glycosylated, explaining in part their lower molecular size. Differences found in N-terminal peptide sequences were unlikely to influence apparent molecular size or enzyme function. Human and bovine P450arom had similar affinities and turnovers for androstenedione (approximately 200 nM, 3/min) and testosterone (approximately 350 nM, 2/min). The porcine isozymes had 10-fold higher affinities but correspondingly lower turnovers, particularly the gonadal P450arom. Overall, the catalytic efficiency (Vmax/Km) was similar for all but porcine gonadal P450arom which was much lower. These data emphasize the structural and functional variability of even the most conserved of proteins among diverse species wherein such differences have previously remained unexpected.
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Affiliation(s)
- C Jo Corbin
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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Corbin CJ, Moran FM, Vidal JD, Ford JJ, Wise T, Mapes SM, Njar VC, Brodie AM, Conley AJ. Biochemical assessment of limits to estrogen synthesis in porcine follicles. Biol Reprod 2003; 69:390-7. [PMID: 12672661 DOI: 10.1095/biolreprod.103.015578] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Limits to estrogen production by early and late preovulatory porcine follicles were assessed by comparing enzymatic capacities for androgen (17,20-lyase) and estrogen (aromatase) synthesis in theca interna and granulosa, support of enzyme activities by the redox partner proteins NADPH-cytochrome P450 oxidoreductase (reductase) and cytochrome b5, and tissue-specific expression and regulation of these proteins. Parameters included follicular fluid (FF) estradiol and progesterone levels, theca and granulosa aromatase and reductase activities, and theca 17,20-lyase activity. Expression of proteins responsible for these activities, aromatase (P450arom) and 17 alpha-hydroxylase/17,20-lyase (P450c17) cytochromes P450, reductase, and for the first time in ovarian tissues cytochrome b5, were examined by Western immunoblot and immunocytochemistry. Theca and granulosa aromatase activities were as much as 100-fold lower than theca 17,20-lyase activity, but aromatase was correlated with only the log of FF estradiol. Granulosa reductase activity was twice that of the theca, and cytochrome b5 expression was clearly identified in both the theca and granulosa layers, as was P450arom, but was not highly correlated with either 17,20-lyase or aromatase activities. Reductase expression did not change with stage of follicular development, but cytochrome b5, P450c17, and P450arom were markedly lower in post-LH tissues. These data indicate that aromatase and not 17,20-lyase must limit porcine follicular estradiol synthesis, but this limitation is not reflected acutely in FF steroid concentrations. Neither reductase nor cytochrome b5 appear to regulate P450 activities, but the expression of cytochrome b5 in granulosa and theca suggests possible alternative roles for this protein in follicular development or function.
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Affiliation(s)
- C J Corbin
- Department of Population Health & Reproduction, School of Veterinary Medicine, University of California, Davis, California 95616, USA
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Golovine K, Schwerin M, Vanselow J. Three different promoters control expression of the aromatase cytochrome p450 gene (cyp19) in mouse gonads and brain. Biol Reprod 2003; 68:978-84. [PMID: 12604651 DOI: 10.1095/biolreprod.102.008037] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Aromatase cytochrome P450, the key enzyme of estrogen biosynthesis, is encoded by Cyp19. To elucidate the complex regulation of this gene in mouse gonads (ovary and testis) and brain (thalamic/hypothalamic areas), Cyp19 transcripts were isolated using rapid amplification of cDNA 5' ends and transcript concentrations were estimated in juveniles at different postnatal days (P0, P7, and P14) and in adult animals by real time polymerase chain reaction (PCR). In addition, the murine Cyp19 locus including all known exons and promoters was reconstructed from a recently published sequence of a mouse bacterial artificial chromosome. From each of the tissues investigated, Cyp19 transcripts with a specific 5' untranslated region (5' UTR) were isolated: T(ov) from ovary, T(br) from brain, and T(tes) from testis. T(tes) included a novel 5' UTR that did not show sequence similarities to other Cyp19 transcripts. Real time PCR experiments revealed similar levels of Cyp19 transcript concentrations in neonatal gonads of both sexes. The majority of transcripts were T(ov) in ovaries and T(tes) in testes. During further postnatal development, testicular Cyp19 transcript concentrations transiently decreased, but the contributions of different transcript variants basically remained unchanged. However, ovarian Cyp19 transcript concentrations increased by about 100 times, and almost 100% of all Cyp19 transcripts were identified as T(ov) in adult ovaries. Brains of both sexes showed highest transcript concentrations at P0. However, concentrations in female brains were reduced to adult levels earlier than in male brains. In brains of both sexes, T(br) was found to predominate throughout postnatal life. The results suggest that the mouse Cyp19 gene includes three different promoters that specifically direct expression in ovary, testis, and brain.
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Affiliation(s)
- Konstantin Golovine
- Research Unit Molecular Biology, Research Institute for the Biology of Farm Animals, 18196 Dummerstorf, Germany
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Roselli CE, Resko JA, Stormshak F. Estrogen synthesis in fetal sheep brain: effect of maternal treatment with an aromatase inhibitor. Biol Reprod 2003; 68:370-4. [PMID: 12533398 DOI: 10.1095/biolreprod.102.007633] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The aim of the present study was to determine whether the fetal lamb brain has the capacity to aromatize androgens to estrogens during the critical period for sexual differentiation. We also determined whether administration of the aromatase-inhibitor 1,4,6-androstatriene-3,17-dione (ATD) could cross the placenta and inhibit aromatase activity (AA) in fetal brain. Eight pregnant ewes were utilized. On Day 50 of pregnancy, four ewes were given ATD-filled Silastic implants, and the other four ewes received sham surgeries. The fetuses were surgically delivered 2 wk later (Day 64 of gestation). High levels of AA (0.8-1.4 pmol/h/mg protein) were present in the hypothalamus and amygdala. Lower levels (0.02-0.1 pmol/h/mg protein) were measured in brain stem regions, cortex, and olfactory bulbs. The Michaelis-Menten dissociation constant (K(m)) for aromatase in the fetal sheep brain was 3-4 nM. No significant sex differences in AA were observed in brain. Treatment with ATD produced significant inhibition of AA in most brain areas but did not significantly alter serum profiles of the major sex steroids in maternal and fetal serum. Concentrations of testosterone in serum from the umbilical artery and vein were significantly greater in male than in female fetuses. No other sex differences in serum steroids were observed. These data demonstrate that high levels of AA are found in the fetal sheep hypothalamus and amygdala during the critical period for sexual differentiation. They also demonstrate that AA can be inhibited in the fetal lamb brain by treating the mother with ATD, without harming fetal development.
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Affiliation(s)
- Charles E Roselli
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon 97201-3098, USA.
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Nelson DR. Comparison of P450s from human and fugu: 420 million years of vertebrate P450 evolution. Arch Biochem Biophys 2003; 409:18-24. [PMID: 12464240 DOI: 10.1016/s0003-9861(02)00553-2] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The fugu (pufferfish) genome has been sequenced, and a second genome assembly was released 17 May 2002. Exhaustive searches were made to identify all P450 genes and pseudogenes from the earlier release of 26 October 2001. P450 genes assembled as completely as possible from these data were used to do additional searches of the newer assembly and all P450 genes and pseudogenes in the available fugu sequence data have been identified, compared to human P450s, and assigned names. There are 54 P450 genes in fugu and 1 nearly intact pseudogene (CYP3A50P). CYP1A is missing much of its N-terminal half; however, 45 P450 genes are completely assembled. Eight others are lacking only one or two exons or less. CYP2X4 is known only from an EST. This may be a 55th P450 gene if it represents an accurate sequence. In addition to 2X4, there are 16 other pseudogene fragments or small pieces of P450 genes. At the P450 family level, 17 of 18 mammalian families are found in fugu. CYP39 is the only CYP family missing and it is not seen in any other fish sequence data either. The CYP2 family shows the largest degree of divergence. In the CYP2 family, only CYP2R1 and CYP2U1 are conserved as recognizable subfamilies across species. Intron-exon boundaries are largely preserved across 420 million years of evolution.
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Affiliation(s)
- David R Nelson
- Department of Molecular Sciences, University of Tennessee, 858 Madison Avenue, Memphis 38163, USA.
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Dalla Valle L, Ramina A, Vianello S, Belvedere P, Colombo L. Cloning of two mRNA variants of brain aromatase cytochrome P450 in rainbow trout (Oncorhynchus mykiss Walbaum). J Steroid Biochem Mol Biol 2002; 82:19-32. [PMID: 12429136 DOI: 10.1016/s0960-0760(02)00143-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This work describes the molecular cloning of the cDNA encoding the rainbow trout (Oncorhynchus mykiss Walbaum) brain cytochrome P450arom by means of reverse transcriptase and polymerase chain reaction (RT-PCR) and 5'- and 3'-rapid amplification of cDNA ends (RACE) analyses. The results obtained demonstrate that, as in other teleost fishes, the trout genome contains, besides the gene previously identified in the ovary, a second CYP19 gene (CYP19B) expressed at high level in the brain. Moreover, two P450aromB mRNAs, forms I and II, were found to be transcribed in trout. Form I (1816 sequenced nt) contains an open reading frame (ORF) of 1464b, a 5'-untranslated terminal region (UTR) of 124b and at least 228b in the 3'-UTR (incomplete, as the polyadenylation signal was not determined). Form II (1930 sequenced nt) contains an ORF of 1362b, a 5'-UTR of 340b and the same 3'-UTR as form I. Form II lacks the first 34 amino acids of form I, corresponding to the membrane-anchoring segment, whereas the sequence of the remaining coding region is almost the same in the two forms, resulting in proteins of 454 and 488 amino acids, respectively. Whether the two transcripts derive from the same gene by alternative splicing or are encoded by different CYP19B genes remains to be clarified. On Northern blot analyses with brain and ovary specific ORF probes and poly(A)(+)-enriched RNAs from trout ovary and brain, a transcript of about 2.6kb was identified in the ovary, as expected, whereas the full-length mRNA of brain P450arom is about 3.8kb. The brain form is expressed in the brain and gonads, whereas expression in peripheral tissues is limited mostly to the gills. The two trout CYP19 genes are not equivalent in tissue-specific expression, indicating the possibility of distinct promoters and regulatory mechanisms.
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Affiliation(s)
- Luisa Dalla Valle
- Comparative Endocrinology Laboratory, Department of Biology, University of Padova, Via Uu Bassi 58/B, Italy.
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