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  1 / 4423 MEDLINE  
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[PMID]:28744861
[Au] Autor:Pan ZJ; Zhu CK; Wang H; Zhou FJ; Qiang XG
[Ad] Endereço:School of Life Science, Huaiyin Normal University, Huaian, 223300, China.
[Ti] Título:Gonadal morphogenesis and sex differentiation in cultured Ussuri catfish Tachysurus ussuriensis.
[So] Source:J Fish Biol;91(3):866-879, 2017 Sep.
[Is] ISSN:1095-8649
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The objective of this study was to investigate the optimal developmental time to perform sex reversal in Ussuri catfish Tachysurus ussuriensis, to develop monosex breeding in aquaculture. Systematic observations of gonadal sex differentiation of P. ussiriensis were conducted. The genital ridge formed at 9 days post fertilization (dpf) and germ cells begin to proliferate at 17 dpf. The ovarian cavity began forming on 21 dpf and completed by 25 dpf while presumptive testis remained quiescent. The primary oocytes were at the chromatin nucleolus stage by 30 dpf, the peri-nucleolus stage by 44 dpf and the cortical alveoli stage by 64 dpf. The germinal vesicle migrated towards the animal pole (polarization) at 120 dpf. In presumptive testis, germ cells entered into mitosis and blood vessels appeared in the proximal gonad on 30 dpf. The efferent duct anlage appeared on 36 dpf and formation of seminal lobules with spermatogonia and lobules interstitium occurred at 120 dpf. Therefore, gonadal sex differentiation occurred earlier in females than in males, with the histological differentiation preceding cytologic differentiation in T. ussuriensis. This indicates that undifferentiated gonads directly differentiate into ovary or testis between 17 and 21 dpf and artificial induction of sexual reversal by oral steroid administration must be conducted before 17 dpf.
[Mh] Termos MeSH primário: Peixes-Gato/crescimento & desenvolvimento
Diferenciação Sexual/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Aquicultura/métodos
Proliferação Celular
Feminino
Células Germinativas/citologia
Células Germinativas/efeitos dos fármacos
Masculino
Morfogênese
Ovário/citologia
Ovário/efeitos dos fármacos
Ovário/crescimento & desenvolvimento
Testículo/citologia
Testículo/efeitos dos fármacos
Testículo/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1111/jfb.13388


  2 / 4423 MEDLINE  
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[PMID]:29272351
[Au] Autor:Crowder CM; Lassiter CS; Gorelick DA
[Ad] Endereço:Department of Pharmacology & Toxicology, University of Alabama at Birmingham, Birmingham, Alabama.
[Ti] Título:Nuclear Androgen Receptor Regulates Testes Organization and Oocyte Maturation in Zebrafish.
[So] Source:Endocrinology;159(2):980-993, 2018 02 01.
[Is] ISSN:1945-7170
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Androgens act through the nuclear androgen receptor (AR) to regulate gonad differentiation and development. In mice, AR is necessary for spermatogenesis, testis development, and formation of external genitalia in males and oocyte maturation in females. However, the extent to which these phenotypes are conserved in nonmammalian vertebrates is not well understood. Here, we generate zebrafish with a mutation in the ar gene (aruab105/105) and examine the role of AR in sexual determination and gonad development. We found that zebrafish AR regulates male sexual determination, because the majority of aruab105/105 mutant embryos developed ovaries and displayed female secondary sexual characteristics. The small percentage of mutants that developed testes displayed female secondary sexual characteristics, exhibited structurally disorganized testes, and were unable to release or produce normal levels of sperm, demonstrating that AR is necessary for zebrafish testis development and fertility. In females, we found that AR regulates oocyte maturation and fecundity. The aruab105/105 mutant females developed ovaries filled primarily with immature stage I oocytes and few mature stage III oocytes. Two genes whose expression is enriched in wild-type ovaries compared with testes (cyp19a1a, foxl2a) were upregulated in ar mutant testes, and two genes enriched in testes (amh, dmrt1) were upregulated in ar mutant ovaries. These findings demonstrate that AR regulates sexual determination, testis development, and oocyte maturation and suggest that AR regulates sexually dimorphic gene expression. The ar mutant we developed will be useful for modeling human endocrine function in zebrafish.
[Mh] Termos MeSH primário: Oogênese/genética
Receptores Androgênicos/fisiologia
Diferenciação Sexual/genética
Espermatogênese/genética
Testículo/citologia
Testículo/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Animais
Animais Geneticamente Modificados
Núcleo Celular/metabolismo
Embrião não Mamífero
Feminino
Fertilidade/genética
Masculino
Receptores Androgênicos/genética
Testículo/metabolismo
Peixe-Zebra/embriologia
Peixe-Zebra/genética
Peixe-Zebra/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Receptors, Androgen)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:171223
[St] Status:MEDLINE
[do] DOI:10.1210/en.2017-00617


  3 / 4423 MEDLINE  
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[PMID]:29051026
[Au] Autor:Ramos L; Chávez B; Mares L; Valdés E; Vilchis F
[Ad] Endereço:Department of Reproductive Biology, Instituto Nacional de Ciencias Médicas y Nutrición S.Z., Mexico.
[Ti] Título:Mutational analysis of the androgen receptor (NR3C4) gene in patients with 46,XY DSD.
[So] Source:Gene;641:86-93, 2018 Jan 30.
[Is] ISSN:1879-0038
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Androgen insensitivity syndrome (AIS) is an X-linked disorder caused by mutations in the NR3C4 gene, which encodes the androgen receptor (AR). In this study, we performed mutational analyses to identify AR molecular defects, in individuals with 46,XY disorders of sex development (46,XY DSD) and a presumptive diagnosis of AIS. Eighteen different gene mutations, including seven previously unreported new variants, were detected in 26 unrelated cases. These included two deletion mutations (P49fs*185 and E308f*320) in exon 1 and five substitution mutations (p.S792P, p.D829G, p.R832P, p.L839F, and p.K906E) located in the steroid-binding domain. Expression analyses of mutants generated by site-directed mutagenesis indicated that these new gene variants impaired AR function by affecting its binding activity. Seventeen of 18 mutations likely lead to reduced or absent responses to androgens, which may in turn account for the different degrees of undermasculinization observed. Our study provides insight into the functional consequences of these mutations.
[Mh] Termos MeSH primário: Síndrome de Resistência a Andrógenos/genética
Transtornos do Desenvolvimento Sexual/genética
Receptores Androgênicos/genética
Diferenciação Sexual/genética
[Mh] Termos MeSH secundário: Adolescente
Adulto
Criança
Pré-Escolar
Análise Mutacional de DNA
Feminino
Seres Humanos
Lactente
Masculino
México
Mutação/genética
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Receptors, Androgen)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:180110
[Lr] Data última revisão:
180110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171021
[St] Status:MEDLINE


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[PMID]:29174386
[Au] Autor:Li T; Lu Z; Luo R; Gao J; Zhao X; Ma Y
[Ad] Endereço:College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China; Sheep Breeding Biotechnology Engineering Laboratory of Gansu Province, Minqin 733300, China.
[Ti] Título:Expression and cellular localization of double sex and mab-3 related transcription factor 1 in testes of postnatal Small-Tail Han sheep at different developmental stages.
[So] Source:Gene;642:467-473, 2018 Feb 05.
[Is] ISSN:1879-0038
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Double sex and mab-3 related transcription factor 1 (Dmrt1), an evolutionarily conserved gene, is a sex-related gene expressed in male gonads, that is involved in the regulation of sex differentiation, testicular development and reproductive function maintenance. Until now, functional studies on the Dmrt1 gene in sheep (Ovis aries) have been lacking. In this study, testis, heart, liver, spleen, lung, kidney and longissimus dorsi muscle tissues were collected from Small-Tail Han sheep at 0, 2, 5, 12 and 24months after birth (mab). Dmrt1 expression and cellular localization were detected in various testicular tissues by quantitative real time PCR (qRT-PCR), western blot and immunohistochemistry methods. The morphological structures of testicular tissues at different developmental stages were observed by hematoxylin & eosin (HE) staining. The Dmrt1 mRNA expression levels in 12 and 24 mab sheep were significantly higher than those in 0 and 2 mab sheep (P<0.05), and Dmrt1 protein expression showed a similar trend. The qRT-PCR results in various tissues at 12 mab showed that Dmrt1 mRNA was predominantly expressed in testes. Immunohistochemical staining in testes at different developmental stages showed that Dmrt1 protein immunoreactive responses were mainly localized in Sertoli cells and gonocytes at 0, 2 and 5 mab, while they were localized in spermatocytes, sperm cells and some spermatogonia and Sertoli cells at 12 and 24 mab. We speculate that the Dmrt1 gene plays a vital role in postnatal sheep spermatogenesis, perhaps by regulating the maturation and functional maintenance of Sertoli cells, the proliferation and differentiation of gonocytes in prepubertal sheep testes, and the mitosis and meiosis of germ cells in adult sheep, but the specific mechanisms underlying these phenomena must be further studied and verified.
[Mh] Termos MeSH primário: Ovinos/crescimento & desenvolvimento
Testículo/crescimento & desenvolvimento
Fatores de Transcrição/genética
Fatores de Transcrição/metabolismo
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Proliferação Celular
Regulação da Expressão Gênica no Desenvolvimento
Masculino
Células de Sertoli/metabolismo
Diferenciação Sexual
Ovinos/genética
Ovinos/metabolismo
Espermatócitos/citologia
Espermatócitos/metabolismo
Espermatogênese
Testículo/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Transcription Factors)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171226
[Lr] Data última revisão:
171226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171128
[St] Status:MEDLINE


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[PMID]:29016690
[Au] Autor:Wu GC; Li HW; Tey WG; Lin CJ; Chang CF
[Ad] Endereço:Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan.
[Ti] Título:Expression profile of amh/Amh during bi-directional sex change in the protogynous orange-spotted grouper Epinephelus coioides.
[So] Source:PLoS One;12(10):e0185864, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Gonadal differentiation is tightly regulated by the initial sex determining gene and the downstream sex-related genes in vertebrates. However, sex change in fish can alter the sexual fate from one sex to the other. Chemical-induced maleness in the protogynous orange-spotted grouper is transient, and a reversible sex change occurs after the chemical treatment is withdrawn. We used these characteristics to study Amh signaling during bi-directional sex change in the grouper. We successfully induced the female-to-male sex change by chemical (aromatase inhibitor, AI, or methyltestosterone, MT) treatment. A dormant gonad (a low proliferation rate of early germ cells and no characteristics of both sexes) was found during the transient phase of reversible male-to-female sex change after the withdrawal of chemical administration. Our results showed that amh (anti-mullerian hormone) and its receptor amhr2 (anti-mullerian hormone receptor type 2) were significantly increased in the gonads during the process of female-to-male sex change. Amh is expressed in the Sertoli cells surrounding the type A spermatogonia in the female-to-male grouper. Male-related gene (dmrt1 and sox9) expression was immediately decreased in MT-terminated males during the reversible male-to-female sex change. However, Amh expression was found in the surrounding cells of type A spermatogonia-like cells during the transient phase of reversible male-to-female sex change. This phenomenon is correlated with the dormancy of type A spermatogonia-like cells. Thus, Amh signaling is suggested to play roles in regulating male differentiation during the female-to-male sex change and in inhibiting type-A spermatogonia-like cell proliferation/differentiation during the reversible male-to-female sex change. We suggest that Amh signaling might play dual roles during bi-directional sex change in grouper.
[Mh] Termos MeSH primário: Hormônio Antimülleriano/genética
Inibidores da Aromatase/farmacologia
Regulação da Expressão Gênica no Desenvolvimento
Metiltestosterona/farmacologia
Receptores de Peptídeos/genética
Receptores de Fatores de Crescimento Transformadores beta/genética
Diferenciação Sexual/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Hormônio Antimülleriano/metabolismo
Feminino
Masculino
Ovário/citologia
Ovário/efeitos dos fármacos
Ovário/metabolismo
Perciformes
Receptores de Peptídeos/metabolismo
Receptores de Fatores de Crescimento Transformadores beta/metabolismo
Fatores de Transcrição SOX9/genética
Fatores de Transcrição SOX9/metabolismo
Células de Sertoli/citologia
Células de Sertoli/efeitos dos fármacos
Células de Sertoli/metabolismo
Processos de Determinação Sexual
Diferenciação Sexual/genética
Transdução de Sinais
Espermatogônias/citologia
Espermatogônias/efeitos dos fármacos
Espermatogônias/metabolismo
Fatores de Transcrição/genética
Fatores de Transcrição/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Aromatase Inhibitors); 0 (DMRT1 protein); 0 (Receptors, Peptide); 0 (Receptors, Transforming Growth Factor beta); 0 (SOX9 Transcription Factor); 0 (Transcription Factors); 0 (anti-Mullerian hormone receptor); 80497-65-0 (Anti-Mullerian Hormone); V9EFU16ZIF (Methyltestosterone)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171011
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185864


  6 / 4423 MEDLINE  
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[PMID]:28977609
[Au] Autor:Morishita M; Maejima S; Tsukahara S
[Ad] Endereço:Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan.
[Ti] Título:Gonadal Hormone-Dependent Sexual Differentiation of a Female-Biased Sexually Dimorphic Cell Group in the Principal Nucleus of the Bed Nucleus of the Stria Terminalis in Mice.
[So] Source:Endocrinology;158(10):3512-3525, 2017 Oct 01.
[Is] ISSN:1945-7170
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We recently reported a female-biased sexually dimorphic area in the mouse brain in the boundary region between the preoptic area and the bed nucleus of the stria terminalis (BNST). We reexamined this area and found that it is a ventral part of the principal nucleus of the BNST (BNSTp). The BNSTp is a male-biased sexually dimorphic nucleus, but the ventral part of the BNSTp (BNSTpv) exhibits female-biased sex differences in volume and neuron number. The volume and neuron number of the BNSTpv were increased in males by neonatal orchiectomy and decreased in females by treatment with testosterone, dihydrotestosterone, or estradiol within 5 days after birth. Sex differences in the volume and neuron number of the BNSTpv emerged before puberty. These sex differences became prominent in adulthood with increasing volume in females and loss of neurons in males during the pubertal/adolescent period. Prepubertal orchiectomy did not affect the BNSTpv, although prepubertal ovariectomy reduced the volume increase and induced loss of neurons in the female BNSTpv. In contrast, the volume and neuron number of male-biased sexually dimorphic nuclei that are composed of mainly calbindin neurons and are located in the preoptic area and BNST were decreased by prepubertal orchiectomy but not affected by prepubertal ovariectomy. Testicular testosterone during the postnatal period may defeminize the BNSTpv via binding directly to the androgen receptor and indirectly to the estrogen receptor after aromatization, although defeminization may proceed independently of testicular hormones in the pubertal/adolescent period. Ovarian hormones may act to feminize the BNSTpv during the pubertal/adolescent period.
[Mh] Termos MeSH primário: Neurônios/citologia
Área Pré-Óptica/anatomia & histologia
Núcleos Septais/anatomia & histologia
Diferenciação Sexual
[Mh] Termos MeSH secundário: Androgênios/farmacologia
Animais
Animais Recém-Nascidos
Calbindinas/metabolismo
Contagem de Células
Di-Hidrotestosterona/farmacologia
Estradiol/farmacologia
Estrogênios/farmacologia
Feminino
Imagem Tridimensional
Imuno-Histoquímica
Hibridização in Situ Fluorescente
Masculino
Camundongos
Proteínas do Tecido Nervoso/metabolismo
Neurônios/efeitos dos fármacos
Proteínas Nucleares/metabolismo
Orquiectomia
Tamanho do Órgão
Ovariectomia
Área Pré-Óptica/citologia
Área Pré-Óptica/efeitos dos fármacos
RNA Mensageiro/metabolismo
Núcleos Septais/citologia
Núcleos Septais/efeitos dos fármacos
Testosterona/farmacologia
Quinases Ativadas por p21/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Androgens); 0 (Calbindins); 0 (Estrogens); 0 (Nerve Tissue Proteins); 0 (NeuN protein, mouse); 0 (Nuclear Proteins); 0 (RNA, Messenger); 08J2K08A3Y (Dihydrotestosterone); 3XMK78S47O (Testosterone); 4TI98Z838E (Estradiol); EC 2.7.11.1 (Pak3 protein, mouse); EC 2.7.11.1 (p21-Activated Kinases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:171005
[St] Status:MEDLINE
[do] DOI:10.1210/en.2017-00240


  7 / 4423 MEDLINE  
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[PMID]:28911176
[Au] Autor:Tang H; Chen Y; Liu Y; Yin Y; Li G; Guo Y; Liu X; Lin H
[Ad] Endereço:State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
[Ti] Título:New Insights Into the Role of Estrogens in Male Fertility Based on Findings in Aromatase-Deficient Zebrafish.
[So] Source:Endocrinology;158(9):3042-3054, 2017 Sep 01.
[Is] ISSN:1945-7170
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:It has been demonstrated that estrogens are indispensable for male fertility in mammals. Aromatase (encoded by CYP19) catalyzes the final step of estradiol biosynthesis. However, less is known about the role of aromatase in male fertility in nonmammalian species. Fish aromatase is encoded by two separate genes: the gonad-specific cyp19a1a and the brain-specific cyp19a1b. In a recent study, we used transcription activatorlike effector nucleases to systematically generate cyp19a1a and cyp19a1b mutant lines and a cyp19a1a;cyp19a1b double-mutant line in zebrafish and demonstrated that cyp19a1a was indispensable for sex differentiation. In this study, we focused on male fertility in these aromatase-deficient zebrafish. Our results showed that all aromatase-deficient male fish had normal fertility even at 1 year after fertilization. Interestingly, we observed more spermatozoa in the cyp19a1a and double-mutant males than in the wild-type and cyp19a1b mutant males. The whole-body androgen levels, follicle-stimulating hormone ß and luteinizing hormone ß protein levels in the pituitary, and transcript levels of genes known to be involved in spermatogenesis and steroidogenesis in the testes were significantly higher in the cyp19a1a mutant and aromatase double-mutant males than in the wild-type and cyp19a1b mutant males. These results might explain why more spermatozoa were observed in these fish. Collectively, our findings indicate that estrogens are not needed to achieve and maintain normal fertility in male zebrafish. This finding challenges the traditional view that estrogens are indispensable for male fertility.
[Mh] Termos MeSH primário: Aromatase/genética
Estrogênios/farmacologia
Fertilidade/efeitos dos fármacos
Diferenciação Sexual
Testículo/efeitos dos fármacos
Proteínas de Peixe-Zebra/genética
Peixe-Zebra
[Mh] Termos MeSH secundário: Animais
Animais Geneticamente Modificados
Embrião não Mamífero
Feminino
Fertilidade/genética
Hormônios Esteroides Gonadais/biossíntese
Masculino
Diferenciação Sexual/efeitos dos fármacos
Diferenciação Sexual/genética
Espermatogênese/efeitos dos fármacos
Espermatogênese/genética
Testículo/metabolismo
Peixe-Zebra/embriologia
Peixe-Zebra/genética
Peixe-Zebra/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Estrogens); 0 (Gonadal Steroid Hormones); 0 (Zebrafish Proteins); EC 1.14.14.1 (Aromatase); EC 1.14.14.1 (Cyp19a1a protein, zebrafish); EC 1.14.14.1 (Cyp19a1b protein, zebrafish)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171002
[Lr] Data última revisão:
171002
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170916
[St] Status:MEDLINE
[do] DOI:10.1210/en.2017-00156


  8 / 4423 MEDLINE  
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[PMID]:28911174
[Au] Autor:Hirst CE; Major AT; Ayers KL; Brown RJ; Mariette M; Sackton TB; Smith CA
[Ad] Endereço:Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.
[Ti] Título:Sex Reversal and Comparative Data Undermine the W Chromosome and Support Z-linked DMRT1 as the Regulator of Gonadal Sex Differentiation in Birds.
[So] Source:Endocrinology;158(9):2970-2987, 2017 Sep 01.
[Is] ISSN:1945-7170
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The exact genetic mechanism regulating avian gonadal sex differentiation has not been completely resolved. The most likely scenario involves a dosage mechanism, whereby the Z-linked DMRT1 gene triggers testis development. However, the possibility still exists that the female-specific W chromosome may harbor an ovarian determining factor. In this study, we provide evidence that the universal gene regulating gonadal sex differentiation in birds is Z-linked DMRT1 and not a W-linked (ovarian) factor. Three candidate W-linked ovarian determinants are HINTW, female-expressed transcript 1 (FET1), and female-associated factor (FAF). To test the association of these genes with ovarian differentiation in the chicken, we examined their expression following experimentally induced female-to-male sex reversal using the aromatase inhibitor fadrozole (FAD). Administration of FAD on day 3 of embryogenesis induced a significant loss of aromatase enzyme activity in female gonads and masculinization. However, expression levels of HINTW, FAF, and FET1 were unaltered after experimental masculinization. Furthermore, comparative analysis showed that FAF and FET1 expression could not be detected in zebra finch gonads. Additionally, an antibody raised against the predicted HINTW protein failed to detect it endogenously. These data do not support a universal role for these genes or for the W sex chromosome in ovarian development in birds. We found that DMRT1 (but not the recently identified Z-linked HEMGN gene) is male upregulated in embryonic zebra finch and emu gonads, as in the chicken. As chicken, zebra finch, and emu exemplify the major evolutionary clades of birds, we propose that Z-linked DMRT1, and not the W sex chromosome, regulates gonadal sex differentiation in birds.
[Mh] Termos MeSH primário: Aves
Cromossomos Sexuais/genética
Processos de Determinação Sexual/genética
Diferenciação Sexual/genética
Fatores de Transcrição/fisiologia
[Mh] Termos MeSH secundário: Animais
Aves/embriologia
Aves/genética
Embrião de Galinha
Galinhas
Desenvolvimento Embrionário
Feminino
Feminização/embriologia
Feminização/genética
Tentilhões/embriologia
Tentilhões/genética
Regulação da Expressão Gênica no Desenvolvimento
Gônadas
Masculino
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DMRT1 protein); 0 (Transcription Factors)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171002
[Lr] Data última revisão:
171002
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170916
[St] Status:MEDLINE
[do] DOI:10.1210/en.2017-00316


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[PMID]:28910392
[Au] Autor:Ortega MT; Foote DJ; Nees N; Erdmann JC; Bangs CD; Rosenfeld CS
[Ad] Endereço:Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America.
[Ti] Título:Karyotype analysis and sex determination in Australian Brush-turkeys (Alectura lathami).
[So] Source:PLoS One;12(9):e0185014, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Sexual differentiation across taxa may be due to genetic sex determination (GSD) and/or temperature sex determination (TSD). In many mammals, males are heterogametic (XY); whereas females are homogametic (XX). In most birds, the opposite is the case with females being heterogametic (ZW) and males the homogametic sex (ZZ). Many reptile species lack sex chromosomes, and instead, sexual differentiation is influenced by temperature with specific temperatures promoting males or females varying across species possessing this form of sexual differentiation, although TSD has recently been shown to override GSD in Australian central beaded dragons (Pogona vitticeps). There has been speculation that Australian Brush-turkeys (Alectura lathami) exhibit TSD alone and/or in combination with GSD. Thus, we sought to determine if this species possesses sex chromosomes. Blood was collected from one sexually mature female and two sexually mature males residing at Sylvan Heights Bird Park (SHBP) and shipped for karyotype analysis. Karyotype analysis revealed that contrary to speculation, Australian Brush-turkeys possess the classic avian ZW/ZZ sex chromosomes. It remains a possibility that a biased primary sex ratio of Australian Brush-turkeys might be influenced by maternal condition prior to ovulation that result in her laying predominantly Z- or W-bearing eggs and/or sex-biased mortality due to higher sensitivity of one sex in environmental conditions. A better understanding of how maternal and extrinsic factors might differentially modulate ovulation of Z- or W-bearing eggs and hatching of developing chicks possessing ZW or ZZ sex chromosomes could be essential in conservation strategies used to save endangered members of Megapodiidae.
[Mh] Termos MeSH primário: Cariotipagem/métodos
Cromossomos Sexuais/genética
Perus/genética
[Mh] Termos MeSH secundário: Animais
Feminino
Masculino
Processos de Determinação Sexual
Diferenciação Sexual
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171012
[Lr] Data última revisão:
171012
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170915
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185014


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[PMID]:28903904
[Au] Autor:Kang Y; Guan GJ; Hong YH
[Ad] Endereço:Laboratory of Fish Sex Differentiation and Stem Cell Biology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China.
[Ti] Título:Insights of sex determination and differentiation from medaka as a teleost model.
[So] Source:Yi Chuan;39(6):441-454, 2017 Jun 20.
[Is] ISSN:0253-9772
[Cp] País de publicação:China
[La] Idioma:eng
[Ab] Resumo:The mechanisms of sex determination and differentiation in fish are highly divergent with a broad range of gonadal differentiation types from hermaphroditism to gonochorism. Multiple triggers regulate the process of sexual differentiation including genetic or environmental factors (temperature, light, hormones and/or pH value, etc.). In recent years, with the advances of molecular technologies and genetic engineering approaches, there are significant breakthroughs in identifying the master genes of vertebrate sex determination and differentiation. In this review, we explore the fundamental and molecular mechanisms underlying the sexual differentiation in teleost fish, using medaka (Oryzias latipes) as a model. We focus on the male pathways and factors, particularly on dmrt1, gsdf and amh genes involved in testicular differentiation, sexual reversal and plasticity. It is anticipated that new techniques will likely be developed in the field of sex manipulations and monosex breeding for fish aquaculture in the future.
[Mh] Termos MeSH primário: Oryzias/genética
Processos de Determinação Sexual/genética
Diferenciação Sexual/genética
[Mh] Termos MeSH secundário: Animais
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170915
[St] Status:MEDLINE
[do] DOI:10.16288/j.yczz.17-140



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