Base de dados : MEDLINE
Pesquisa : A11.284.187.865 [Categoria DeCS]
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  1 / 8877 MEDLINE  
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[PMID]:29385171
[Au] Autor:Aguayo A; Martin CS; Huddy TF; Ogawa-Okada M; Adkins JL; Steele AD
[Ad] Endereço:Department of Biological Sciences, California State Polytechnic University Pomona, Pomona, CA, United States of America.
[Ti] Título:Sex differences in circadian food anticipatory activity are not altered by individual manipulations of sex hormones or sex chromosome copy number in mice.
[So] Source:PLoS One;13(1):e0191373, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Recent studies in mice have demonstrated a sexual dimorphism in circadian entrainment to scheduled feeding. On a time restricted diet, males tend to develop food anticipatory activity (FAA) sooner than females and with a higher amplitude of activity. The underlying cause of this sex difference remains unknown. One study suggests that sex hormones, both androgens and estrogens, modulate food anticipatory activity in mice. Here we present results suggesting that the sex difference in FAA is unrelated to gonadal sex hormones. While a sex difference between males and females in FAA on a timed, calorie restricted diet was observed there were no differences between intact and gonadectomized mice in the onset or magnitude of FAA. To test other sources of the sex difference in circadian entrainment to scheduled feeding, we used sex chromosome copy number mutants, but there was no difference in FAA when comparing XX, XY-, XY-;Sry Tg, and XX;Sry Tg mice, demonstrating that gene dosage of sex chromosomes does not mediate the sex difference in FAA. Next, we masculinized female mice by treating them with 17-beta estradiol during the neonatal period; yet again, we saw no difference in FAA between control and masculinized females. Finally, we observed that there was no longer a sex difference in FAA for older mice, suggesting that the sex difference in FAA is age-dependent. Thus, our study demonstrates that singular manipulations of gonadal hormones, sex chromosomes, or developmental patterning are not able to explain the difference in FAA between young male and female mice.
[Mh] Termos MeSH primário: Antecipação Psicológica/fisiologia
Ritmo Circadiano/efeitos dos fármacos
Ritmo Circadiano/genética
Alimentos
Hormônios Esteroides Gonadais/farmacologia
Caracteres Sexuais
Cromossomos Sexuais/genética
[Mh] Termos MeSH secundário: Animais
Antecipação Psicológica/efeitos dos fármacos
Estradiol/farmacologia
Feminino
Dosagem de Genes
Masculino
Camundongos
Camundongos Endogâmicos C57BL
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Gonadal Steroid Hormones); 4TI98Z838E (Estradiol)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180201
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191373


  2 / 8877 MEDLINE  
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[PMID]:29293639
[Au] Autor:Ieda R; Hosoya S; Tajima S; Atsumi K; Kamiya T; Nozawa A; Aoki Y; Tasumi S; Koyama T; Nakamura O; Suzuki Y; Kikuchi K
[Ad] Endereço:Fisheries Laboratory, University of Tokyo, Hamamatsu, Shizuoka, Japan.
[Ti] Título:Identification of the sex-determining locus in grass puffer (Takifugu niphobles) provides evidence for sex-chromosome turnover in a subset of Takifugu species.
[So] Source:PLoS One;13(1):e0190635, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:There is increasing evidence for frequent turnover in sex chromosomes in vertebrates. Yet experimental systems suitable for tracing the detailed process of turnover are rare. In theory, homologous turnover is possible if the new sex-determining locus is established on the existing sex-chromosome. However, there is no empirical evidence for such an event. The genus Takifugu includes fugu (Takifugu rubripes) and its two closely-related species whose sex is most likely determined by a SNP at the Amhr2 locus. In these species, males are heterozygous, with G and C alleles at the SNP site, while females are homozygous for the C allele. To determine if a shift in the sex-determining locus occurred in another member of this genus, we used genetic mapping to characterize the sex-chromosome systems of Takifugu niphobles. We found that the G allele of Amhr2 is absent in T. niphobles. Nevertheless, our initial mapping suggests a linkage between the phenotypic sex and the chromosome 19, which harbors the Amhr2 locus. Subsequent high-resolution analysis using a sex-reversed fish demonstrated that the sex-determining locus maps to the proximal end of chromosome 19, far from the Amhr2 locus. Thus, it is likely that homologous turnover involving these species has occurred. The data also showed that there is a male-specific reduction of recombination around the sex-determining locus. Nevertheless, no evidence for sex-chromosome differentiation was detected: the reduced recombination depended on phenotypic sex rather than genotypic sex; no X- or Y-specific maker was obtained; the YY individual was viable. Furthermore, fine-scale mapping narrowed down the new sex-determining locus to the interval corresponding to approximately 300-kb of sequence in the fugu genome. Thus, T. niphobles is determined to have a young and small sex-determining region that is suitable for studying an early phase of sex-chromosome evolution and the mechanisms underlying turnover of sex chromosome.
[Mh] Termos MeSH primário: Cromossomos Sexuais
Processos de Determinação Sexual
Takifugu/genética
[Mh] Termos MeSH secundário: Animais
Cruzamentos Genéticos
Feminino
Masculino
Filogenia
Polimorfismo de Nucleotídeo Único
Locos de Características Quantitativas
Recombinação Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180221
[Lr] Data última revisão:
180221
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180103
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190635


  3 / 8877 MEDLINE  
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[PMID]:29186711
[Au] Autor:Viana PF; Ezaz T; Marajó L; Ferreira M; Zuanon J; Cioffi MB; Bertollo LAC; Gross MC; Feldberg E
[Ad] Endereço:Instituto Nacional de Pesquisas da Amazônia, Coordenação de Biodiversidade, Universidade Federal do Amazonas, Manaus, Brazil.
[Ti] Título:Genomic Organization of Repetitive DNAs and Differentiation of an XX/XY Sex Chromosome System in the Amazonian Puffer Fish, Colomesus asellus (Tetraodontiformes).
[So] Source:Cytogenet Genome Res;153(2):96-104, 2017.
[Is] ISSN:1424-859X
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:The genus Colomesus is the sole representative of the family Tetraodontidae in the Amazon region. Here, Colomesus asellus was analyzed using conventional and molecular cytogenetic protocols. Its diploid chromosome number is 2n = 46 with 12 meta-, 10 submeta-, 16 subtelo-, and 8 acrocentric chromosomes and a fundamental number of FN = 84. An XX/XY sex chromosome system was identified. Mapping of 18S rDNA correlated with the nucleolus organizer regions (Ag-NORs) in the short arms of the 2 X chromosomes in females and in the Y chromosome in males. C-banding revealed heterochromatin in the centromeric regions of all chromosomes, except for pair 3. Prominent sex chromosome-specific heterochromatin amplification was observed, covering the short arms of the Y chromosome almost entirely. FISH with telomeric and tropomyosin (tpm1) sequences, respectively, revealed terminal signals in all chromosomes. The analysis of extended DNA fibers confirmed the colocalization and the interspersed pattern of the telomeric and tpm1 sequences. Thus, this study highlights the remarkable evolutionary dynamism presented by the Amazonian puffer fish regarding the differentiation of a heteromorphic XY sex chromosome system and a particular sex-specific amplification of rDNA sites. This is the first record of such an association in the Tetraodontidae family.
[Mh] Termos MeSH primário: Cromossomos Sexuais/genética
Processos de Determinação Sexual
Tetraodontiformes/genética
[Mh] Termos MeSH secundário: Animais
Antígenos Nucleares/genética
Brasil
Bandeamento Cromossômico
DNA Ribossômico/genética
Feminino
Amplificação de Genes
Hibridização in Situ Fluorescente
Masculino
RNA Ribossômico 18S/genética
Sequências Repetitivas de Ácido Nucleico
Telômero/genética
Telômero/ultraestrutura
Tropomiosina/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antigens, Nuclear); 0 (DNA, Ribosomal); 0 (RNA, Ribosomal, 18S); 0 (Tropomyosin); 0 (nucleolar organizer region associated proteins)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171130
[St] Status:MEDLINE
[do] DOI:10.1159/000484423


  4 / 8877 MEDLINE  
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[PMID]:29183018
[Au] Autor:Giovannotti M; Nisi Cerioni P; Slimani T; Splendiani A; Paoletti A; Fawzi A; Olmo E; Caputo Barucchi V
[Ad] Endereço:Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, Italy.
[Ti] Título:Cytogenetic Characterization of a Population of Acanthodactylus lineomaculatus Duméril and Bibron, 1839 (Reptilia, Lacertidae), from Southwestern Morocco and Insights into Sex Chromosome Evolution.
[So] Source:Cytogenet Genome Res;153(2):86-95, 2017.
[Is] ISSN:1424-859X
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Acanthodactylus lineomaculatus is now regarded as an ecotype of A. erythrurus with which it has been recently synonymized. Despite the wide range of A. erythrurus, karyological data for this species are scarce and limited to classical cytogenetic studies carried out in individuals from only 2 locations (central Spain and Spanish enclave of Melilla on the northwestern Mediterranean Moroccan coast). Here, for the first time, we cytogenetically characterized individuals of A. lineomaculatus from the southwestern Moroccan Atlantic coast with the aim to increase the karyological knowledge of this wide-ranging species and to assess if any chromosomal changes can be found in this ecotype in comparison to other populations of this species. The diploid number of the individuals investigated is 2n = 38 which is typical of most lacertids. Active NORs were located telomerically in a medium-small pair of chromosomes, and no inactive NORs were detected. C-banding revealed an intensely heterochromatic W chromosome composed of AT-rich (centromere and long arm telomeric region) and GC-rich (most of the long arm) regions, with extended interstitial telomeric sequences. These telomere-like repeats occupy the GC-rich heterochromatin of the W. The DNA composition of the W represents a trait distinguishing A. lineomaculatus (southwestern Morocco) from A. erythrurus from Spain that possess a DAPI-positive (AT-rich) W chromosome. In conclusion, these results add further evidence to the remarkable karyotype conservation in lacertid lizards, although differences in NOR location and in W chromosome structure among populations could suggest an incipient speciation mediated by chromosome changes in this wide-ranging lizard species.
[Mh] Termos MeSH primário: Evolução Biológica
Lagartos/genética
Cromossomos Sexuais/genética
[Mh] Termos MeSH secundário: Animais
Antígenos Nucleares/genética
Células Cultivadas
Bandeamento Cromossômico
DNA Ribossômico/genética
Feminino
Hibridização in Situ Fluorescente
Cariotipagem
Masculino
Marrocos
RNA Ribossômico 18S/genética
RNA Ribossômico 28S/genética
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antigens, Nuclear); 0 (DNA, Ribosomal); 0 (RNA, Ribosomal, 18S); 0 (RNA, Ribosomal, 28S); 0 (nucleolar organizer region associated proteins)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171129
[St] Status:MEDLINE
[do] DOI:10.1159/000484533


  5 / 8877 MEDLINE  
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[PMID]:28745717
[Au] Autor:Utsunomia R; Scacchetti PC; Hermida M; Fernández-Cebrián R; Taboada X; Fernández C; Bekaert M; Mendes NJ; Robledo D; Mank JE; Taggart JB; Oliveira C; Foresti F; Martínez P
[Ad] Endereço:Departamento de Morfologia, Instituto de Biociências, UNESP, Botucatu, Brazil.
[Ti] Título:Evolution and conservation of Characidium sex chromosomes.
[So] Source:Heredity (Edinb);119(4):237-244, 2017 10.
[Is] ISSN:1365-2540
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Fish species exhibit substantial variation in the degree of genetic differentiation between sex chromosome pairs, and therefore offer the opportunity to study the full range of sex chromosome evolution. We used restriction-site associated DNA sequencing (RAD-seq) to study the sex chromosomes of Characidium gomesi, a species with conspicuous heteromorphic ZW/ZZ sex chromosomes. We screened 9863 single-nucleotide polymorphisms (SNPs), corresponding to ~1 marker/100 kb distributed across the genome for sex-linked variation. With this data set, we identified 26 female-specific RAD loci, putatively located on the W chromosome, as well as 148 sex-associated SNPs showing significant differentiation (average F =0.144) between males and females, and therefore in regions of more recent divergence between the Z and W chromosomes. In addition, we detected 25 RAD loci showing extreme heterozygote deficiency in females but which were in Hardy-Weinberg equilibrium in males, consistent with degeneration of the W chromosome and therefore female hemizygosity. We validated seven female-specific and two sex-associated markers in a larger sample of C. gomesi, of which three localised to the W chromosome, thereby providing useful markers for sexing wild samples. Validated markers were evaluated in other populations and species of the genus Characidium, this exploration suggesting a rapid turnover of W-specific repetitive elements. Together, our analyses point to a complex origin for the sex chromosome of C. gomesi and highlight the utility of RAD-seq for studying the composition and evolution of sex chromosomes systems in wild populations.
[Mh] Termos MeSH primário: Caraciformes/genética
Evolução Molecular
Cromossomos Sexuais/genética
[Mh] Termos MeSH secundário: Animais
Sequência Conservada/genética
Feminino
Genoma
Masculino
Sequências Repetitivas de Ácido Nucleico/genética
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1712
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1038/hdy.2017.43


  6 / 8877 MEDLINE  
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[PMID]:28453634
[Au] Autor:Pucholt P; Wright AE; Conze LL; Mank JE; Berlin S
[Ad] Endereço:Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
[Ti] Título:Recent Sex Chromosome Divergence despite Ancient Dioecy in the Willow Salix viminalis.
[So] Source:Mol Biol Evol;34(8):1991-2001, 2017 Aug 01.
[Is] ISSN:1537-1719
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Sex chromosomes can evolve when recombination is halted between a pair of chromosomes, and this can lead to degeneration of the sex-limited chromosome. In the early stages of differentiation sex chromosomes are homomorphic, and even though homomorphic sex chromosomes are very common throughout animals and plants, we know little about the evolutionary forces shaping these types of sex chromosomes. We used DNA- and RNA-Seq data from females and males to explore the sex chromosomes in the female heterogametic willow, Salix viminalis, a species with ancient dioecy but with homomorphic sex chromosomes. We detected no major sex differences in read coverage in the sex determination (SD) region, indicating that the W region has not significantly degenerated. However, single nucleotide polymorphism densities in the SD region are higher in females compared with males, indicating very recent recombination suppression, followed by the accumulation of sex-specific single nucleotide polymorphisms. Interestingly, we identified two female-specific scaffolds that likely represent W-chromosome-specific sequence. We show that genes located in the SD region display a mild excess of male-biased expression in sex-specific tissue, and we use allele-specific gene expression analysis to show that this is the result of masculinization of expression on the Z chromosome rather than degeneration of female-expression on the W chromosome. Together, our results demonstrate that insertion of small DNA fragments and accumulation of sex-biased gene expression can occur before the detectable decay of the sex-limited chromosome.
[Mh] Termos MeSH primário: Salix/genética
Cromossomos Sexuais/genética
[Mh] Termos MeSH secundário: Alelos
Evolução Biológica
Compensação de Dosagem (Genética)/genética
Expressão Gênica/genética
Regulação da Expressão Gênica de Plantas/genética
Variação Genética/genética
Genoma de Planta/genética
Plantas/genética
Populus/genética
Caracteres Sexuais
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180201
[Lr] Data última revisão:
180201
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1093/molbev/msx144


  7 / 8877 MEDLINE  
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[PMID]:29362783
[Ti] Título:Predetermination of Sex.
[So] Source:JAMA;319(4):413, 2018 01 23.
[Is] ISSN:1538-3598
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Drosophila melanogaster/genética
Processos de Determinação Sexual
[Mh] Termos MeSH secundário: Animais
Pesquisa Biomédica/história
Drosophila melanogaster/fisiologia
Feminino
Genótipo
História do Século XX
Seres Humanos
Masculino
Fenômenos Reprodutivos Fisiológicos
Cromossomos Sexuais
Razão de Masculinidade
[Pt] Tipo de publicação:CLASSICAL ARTICLE; HISTORICAL ARTICLE; JOURNAL ARTICLE
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180131
[Lr] Data última revisão:
180131
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:180125
[St] Status:MEDLINE
[do] DOI:10.1001/jama.2017.12215


  8 / 8877 MEDLINE  
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[PMID]:28469017
[Au] Autor:Abbott JK; Nordén AK; Hansson B
[Ad] Endereço:Department of Biology, Lund University, Sölvegatan 37, 223 62 Lund, Sweden jessica.abbott@biol.lu.se.
[Ti] Título:Sex chromosome evolution: historical insights and future perspectives.
[So] Source:Proc Biol Sci;284(1854), 2017 May 17.
[Is] ISSN:1471-2954
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Many separate-sexed organisms have sex chromosomes controlling sex determination. Sex chromosomes often have reduced recombination, specialized (frequently sex-specific) gene content, dosage compensation and heteromorphic size. Research on sex determination and sex chromosome evolution has increased over the past decade and is today a very active field. However, some areas within the field have not received as much attention as others. We therefore believe that a historic overview of key findings and empirical discoveries will put current thinking into context and help us better understand where to go next. Here, we present a timeline of important conceptual and analytical models, as well as empirical studies that have advanced the field and changed our understanding of the evolution of sex chromosomes. Finally, we highlight gaps in our knowledge so far and propose some specific areas within the field that we recommend a greater focus on in the future, including the role of ecology in sex chromosome evolution and new multilocus models of sex chromosome divergence.
[Mh] Termos MeSH primário: Evolução Molecular
Cromossomos Sexuais/genética
[Mh] Termos MeSH secundário: Animais
Compensação de Dosagem (Genética)
Feminino
Masculino
Processos de Determinação Sexual
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180131
[Lr] Data última revisão:
180131
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE


  9 / 8877 MEDLINE  
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[PMID]:29025588
[Au] Autor:Do CH; Lower KM; Macardle C; Kuss BJ
[Ad] Endereço:College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia.
[Ti] Título:Trisomy 12 assessment by conventional fluorescence in-situ hybridization (FISH), FISH in suspension (FISH-IS) and laser scanning cytometry (LSC) in chronic lymphocytic leukemia.
[So] Source:Cancer Genet;216-217:142-149, 2017 Oct.
[Is] ISSN:2210-7762
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Chronic lymphocytic leukemia (CLL) has an extremely heterogeneous clinical course, and prognostication is based on common genetic abnormalities which are detected by standard cytogenetic methods. However, current methods are restricted by the low number of cells able to be analyzed, resulting in the potential to miss clinically relevant sub-clonal populations of cells. A novel high throughput methodology called fluorescence in situ hybridization in suspension (FISH-IS) incorporates a flow cytometry-based imaging approach with automated analysis of thousands of cells. Here we have demonstrated that the FISH-IS technique is applicable to aneuploidy detection in CLL samples for a range of chromosomes using appropriate centromere probes. This method is able to accurately differentiate between monosomy, disomy and trisomy with a sensitivity of 1% in CLL. An analysis comparing conventional FISH, FISH-IS and laser scanning cytometry (LSC) is presented.
[Mh] Termos MeSH primário: Hibridização in Situ Fluorescente/métodos
Citometria de Varredura a Laser/métodos
Leucemia Linfocítica Crônica de Células B/diagnóstico
Leucemia Linfocítica Crônica de Células B/genética
Trissomia/genética
[Mh] Termos MeSH secundário: Cromossomos Humanos/genética
Seres Humanos
Ploidias
Cromossomos Sexuais/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171014
[St] Status:MEDLINE


  10 / 8877 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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BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde