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1.
Gene ; 764: 145093, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32866588

RESUMO

Phenotypic sex of an organism is determined by molecular changes in the gonads, so-called molecular sex differentiation, which should precede the rise of cellular or anatomical sex-distinguishing features. This study characterized molecular and morphological sex differentiation in sablefish (Anoplopoma fimbria), a marine teleost with established XX/XY genotypic sex determination. Next generation sequencing was conducted on sablefish ovarian and testicular mRNAs to obtain sequences for transcripts associated with vertebrate sex determination and differentiation and early reproductive development. Gene-specific PCRs were developed to determine the distribution and ontogenetic gonadal expression of transcription, growth, steroidogenic and germline factors, as well as gonadotropin and steroid receptors. Molecular changes associated with sex differentiation were first apparent in both XY- and XX-genotype sablefish at ~ 60 mm in body length and prior to histological signs of sex differentiation. The earliest and most robust markers of testicular differentiation were gsdf, amh, dmrt1, cyp11b, star, sox9a, and fshr. Markedly elevated mRNA levels of several steroidogenesis-related genes and ar2 in differentiating testes suggested that androgens play a role in sablefish testicular differentiation. The earliest markers of ovarian differentiation were cyp19a1a, lhcgr, foxl2, nr0b1, and igf3. Other transcripts such as figla, zp3, and pou5f3 were expressed predominantly in XX-genotype fish and significantly increased with the first appearance and subsequent development of primary oocytes. This study provides valuable insight to the developmental sequence of events associated with gonadal sex differentiation in marine teleosts with XX/XY sex determination. It also implicates particular genes in processes of male and female development and establishes robust molecular markers for phenotypic sex in sablefish, useful for ongoing work related to sex control and reproductive sterilization.


Assuntos
Proteínas de Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Perciformes/fisiologia , Processos de Determinação Sexual/genética , Diferenciação Sexual/genética , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Feminino , Proteínas de Peixes/análise , Proteínas de Peixes/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Fenótipo , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Testículo/crescimento & desenvolvimento , Testículo/metabolismo
2.
Science ; 370(6513): 208-214, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33033216

RESUMO

Linking genomic variation to phenotypical traits remains a major challenge in evolutionary genetics. In this study, we use phylogenomic strategies to investigate a distinctive trait among mammals: the development of masculinizing ovotestes in female moles. By combining a chromosome-scale genome assembly of the Iberian mole, Talpa occidentalis, with transcriptomic, epigenetic, and chromatin interaction datasets, we identify rearrangements altering the regulatory landscape of genes with distinct gonadal expression patterns. These include a tandem triplication involving CYP17A1, a gene controlling androgen synthesis, and an intrachromosomal inversion involving the pro-testicular growth factor gene FGF9, which is heterochronically expressed in mole ovotestes. Transgenic mice with a knock-in mole CYP17A1 enhancer or overexpressing FGF9 showed phenotypes recapitulating mole sexual features. Our results highlight how integrative genomic approaches can reveal the phenotypic impact of noncoding sequence changes.


Assuntos
Adaptação Fisiológica/genética , Fator 9 de Crescimento de Fibroblastos/genética , Toupeiras/genética , Elementos Reguladores de Transcrição , Diferenciação Sexual/genética , Esteroide 17-alfa-Hidroxilase/genética , Animais , Inversão Cromossômica , Conjuntos de Dados como Assunto , Feminino , Regulação da Expressão Gênica , Genoma , Camundongos , Camundongos Transgênicos , Sequências de Repetição em Tandem , Testosterona/sangue , Testosterona/genética
3.
Ecotoxicol Environ Saf ; 205: 111367, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32971454

RESUMO

Tebuconazole (TBZ), an azole pesticide, is one of the most frequently detected fungicides in surface water. Despite its harmful effects, mainly related to endocrine disturbance, the consequences of TBZ exposure in amphibians remain poorly understood. Here, we investigated the adverse and delayed effects of TBZ chronic exposure on a native anuran species, often inhabiting cultivated areas, the Italian tree frog (Hyla intermedia). To disclose the multiple mechanisms of action through which TBZ exerts its toxicity we exposed tadpoles over the whole larval period to two sublethal TBZ concentrations (5 and 50 µg/L), and we evaluated histological alterations in three target organs highly susceptible to xenobiotics: liver, kidney, and gonads. We also assessed morphometric and gravimetric parameters: snout-vent length (SVL), body mass (BM), liver somatic index (LSI), and gonad-mesonephros complex index (GMCI) and determined sex ratio, gonadal development, and differentiation. Our results show that TBZ induces irreversible effects on multiple target organs in H. intermedia, exerting its harmful effects through several pathological pathways, including a massive inflammatory response. Moreover, TBZ markedly affects sexual differentiation also by inducing the appearance of sexually undetermined individuals and a general delay of germ cell maturation. Given the paucity of data on the effects of TBZ in amphibians, our results will contribute to a better understanding of the environmental risk posed by this fungicide to the most endangered group of vertebrates.


Assuntos
Fungicidas Industriais/toxicidade , Triazóis/toxicidade , Animais , Anuros/crescimento & desenvolvimento , Gônadas/efeitos dos fármacos , Larva/efeitos dos fármacos , Diferenciação Sexual/efeitos dos fármacos
4.
Urologe A ; 59(11): 1356-1360, 2020 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-32990770

RESUMO

Individuals born with a variant of gender development still have a special status in our dyadic-oriented society that even nowadays impairs their life in many ways. Thus, physicians and parents regulated the life's journey of these children until less than 30 years ago by conducting a gender assignment after birth and its implementation by surgical interventions. This approach was ensued in the hope that the child would develop the relevant gender identity, an assumption that did not hold true in many cases. Only during the last 20 years, especially due to the public relations activities of associations of affected individuals, a process of rethinking has taken place that strives to focus on the child's right to self-determination. Reforms of the Personal Statute Act have already been accomplished. Apart from the entry "female" and "male" for newborn children, the categories "open" and "diverse" also now exist. This should exonerate the parents and enable affected persons to later register a distinct term. A draft Act about the interdiction of gender-modifying interventions in the case of a child unable to consent already exists, but is controversially discussed, particularly among CAH associations that do not class themselves as variants of gender differentiation and still advocate early surgical operations. Furthermore, there is also an absolute necessity for structural reforms on the care level to ensure a competent counselling, support and/or treatment for individuals born with a variant of gender differentiation.


Assuntos
Identidade de Gênero , Diferenciação Sexual , Família , Feminino , Humanos , Recém-Nascido , Masculino , Pais
5.
Proc Biol Sci ; 287(1932): 20200992, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32752987

RESUMO

Most organisms are exposed to bouts of warm temperatures during development, yet we know little about how variation in the timing and continuity of heat exposure influences biological processes. If heat waves increase in frequency and duration as predicted, it is necessary to understand how these bouts could affect thermally sensitive species, including reptiles with temperature-dependent sex determination (TSD). In a multi-year study using fluctuating temperatures, we exposed Trachemys scripta embryos to cooler, male-producing temperatures interspersed with warmer, female-producing temperatures (heat waves) that varied in either timing during development or continuity and then analysed resulting sex ratios. We also quantified the expression of genes involved in testis differentiation (Dmrt1) and ovary differentiation (Cyp19A1) to determine how heat wave continuity affects the expression of genes involved in sexual differentiation. Heat waves applied during the middle of development produced significantly more females compared to heat waves that occurred just 7 days before or after this window, and even short gaps in the continuity of a heat wave decreased the production of females. Continuous heat exposure resulted in increased Cyp19A1 expression while discontinuous heat exposure failed to increase expression in either gene over a similar time course. We report that even small differences in the timing and continuity of heat waves can result in drastically different phenotypic outcomes. This strong effect of temperature occurred despite the fact that embryos were exposed to the same number of warm days during a short period of time, which highlights the need to study temperature effects under more ecologically relevant conditions where temperatures may be elevated for only a few days at a time. In the face of a changing climate, the finding that subtle shifts in temperature exposure result in substantial effects on embryonic development becomes even more critical.


Assuntos
Temperatura Alta , Processos de Determinação Sexual , Tartarugas/fisiologia , Animais , Mudança Climática , Embrião não Mamífero , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Fenótipo , Diferenciação Sexual , Razão de Masculinidade
6.
PLoS One ; 15(7): e0235817, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32678858

RESUMO

Whether marine fish will grow differently in future high pCO2 environments remains surprisingly uncertain. Long-term and whole-life cycle effects are particularly unknown, because such experiments are logistically challenging, space demanding, exclude long-lived species, and require controlled, restricted feeding regimes-otherwise increased consumption could mask potential growth effects. Here, we report on repeated, long-term, food-controlled experiments to rear large populations (>4,000 individuals total) of the experimental model and ecologically important forage fish Menidia menidia (Atlantic silverside) under contrasting temperature (17°, 24°, and 28°C) and pCO2 conditions (450 vs. ~2,200 µatm) from fertilization to ~ a third of this annual species' life span. Quantile analyses of trait distributions showed mostly negative effects of high pCO2 on long-term growth. At 17°C and 28°C, but not at 24°C, high pCO2 fish were significantly shorter [17°C: -5 to -9%; 28°C: -3%] and weighed less [17°C: -6 to -18%; 28°C: -8%] compared to ambient pCO2 fish. Reductions in fish weight were smaller than in length, which is why high pCO2 fish at 17°C consistently exhibited a higher Fulton's k (weight/length ratio). Notably, it took more than 100 days of rearing for statistically significant length differences to emerge between treatment populations, showing that cumulative, long-term CO2 effects could exist elsewhere but are easily missed by short experiments. Long-term rearing had another benefit: it allowed sexing the surviving fish, thereby enabling rare sex-specific analyses of trait distributions under contrasting CO2 environments. We found that female silversides grew faster than males, but there was no interaction between CO2 and sex, indicating that males and females were similarly affected by high pCO2. Because Atlantic silversides are known to exhibit temperature-dependent sex determination, we also analyzed sex ratios, revealing no evidence for CO2-dependent sex determination in this species.


Assuntos
Dióxido de Carbono/análise , Peixes/crescimento & desenvolvimento , Animais , Dióxido de Carbono/metabolismo , Mudança Climática , Feminino , Masculino , Água do Mar/análise , Processos de Determinação Sexual , Diferenciação Sexual , Temperatura
7.
Gene ; 754: 144853, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32531459

RESUMO

The freshwater mussel Hyriopsis cumingii, is the most important species for pearl culture in China. At present, the mechanisms underlying sex differentiation and determination remain unclear in this species. Herein the open reading frame (ORF) of Foxl2 from H. cumingii (Hc-Foxl2) was cloned, and Hc-Foxl2 expression levels in six tissues (the gonad, gill, adductor muscle, foot, mantle, and kidney) were determined. Further, we performed quantitative real-time PCR to compare expressions levels between 1 and 8 months of age and 1-, 2-, and 3-year-old H. cumingii. The localization of Hc-Foxl2 expression in the ovary was analyzed by in situ hybridization, and its function was explored using RNA interference. We found that the ORF region of Hc-Foxl2 was 1215 bp in length, encoded 404 amino acids, and contained conserved FH domains. Hc-Foxl2 was expressed in the male and female tissues, with the expression levels being significantly higher in the ovary than in the testis. In 1-8-month-old H. cumingii, Hc-Foxl2 was expressed at the highest level at 5 months of age, and the gonads began to differentiate at the same time. Moreover, in 1-, 2-, and 3-year-old individuals, Hc-Foxl2 expression levels in the ovaries gradually decreased, but they were higher than those in the testis. Strong hybridization signals for Hc-Foxl2 were detected on the oocyte membrane in 3-year-old female mussels. We also performed double-stranded RNA (dsRNA) interference experiments using three dsRNA strands, which were injected into 5-month-old H. cumingii; the interference effects were the best at 12 h and 48 h post-injection. After interference with Hc-Foxl2, the expression levels of Wnt4, which has an antagonistic relationship with Foxl2 during ovarian development, were slightly increased. Thus, we speculate that Hc-Foxl2 is a female-related gene in H. cumingii and that it is involved in sex differentiation and ovarian development.


Assuntos
Bivalves/metabolismo , Proteína Forkhead Box L2/metabolismo , Diferenciação Sexual , Sequência de Aminoácidos , Animais , Sequência de Bases , Bivalves/genética , Clonagem Molecular , Proteína Forkhead Box L2/genética , Água Doce , Regulação da Expressão Gênica , Filogenia , Homologia de Sequência
8.
PLoS Genet ; 16(6): e1008810, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32497091

RESUMO

Urogenital tract abnormalities are among the most common congenital defects in humans. Male urogenital development requires Hedgehog-GLI signaling and testicular hormones, but how these pathways interact is unclear. We found that Gli3XtJ mutant mice exhibit cryptorchidism and hypospadias due to local effects of GLI3 loss and systemic effects of testicular hormone deficiency. Fetal Leydig cells, the sole source of these hormones in developing testis, were reduced in numbers in Gli3XtJ testes, and their functional identity diminished over time. Androgen supplementation partially rescued testicular descent but not hypospadias in Gli3XtJ mutants, decoupling local effects of GLI3 loss from systemic effects of androgen insufficiency. Reintroduction of GLI3 activator (GLI3A) into Gli3XtJ testes restored expression of Hedgehog pathway and steroidogenic genes. Together, our results show a novel function for the activated form of GLI3 that translates Hedgehog signals to reinforce fetal Leydig cell identity and stimulate timely INSL3 and testosterone synthesis in the developing testis. In turn, exquisite timing and concentrations of testosterone are required to work alongside local GLI3 activity to control development of a functionally integrated male urogenital tract.


Assuntos
Criptorquidismo/genética , Regulação da Expressão Gênica no Desenvolvimento , Células Intersticiais do Testículo/patologia , Proteínas do Tecido Nervoso/metabolismo , Diferenciação Sexual/genética , Proteína Gli3 com Dedos de Zinco/metabolismo , Animais , Criptorquidismo/patologia , Modelos Animais de Doenças , Proteínas Hedgehog/metabolismo , Humanos , Insulina/metabolismo , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Mutação , Proteínas do Tecido Nervoso/genética , Proteínas/metabolismo , Transdução de Sinais/genética , Testosterona/metabolismo , Proteína Gli3 com Dedos de Zinco/genética
9.
Gene ; 755: 144906, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32554048

RESUMO

The olive flounder Paralichthys olivaceus, an important marine fish, shows gender differences in growth. The mechanism on its gonadal differentiation direction affected with exogenous factors still needs to be clarified. The anti-Müllerian hormone (amh) gene is involved in fish testicular differentiation and maintenance. The aim of this study was to investigate the expression of the flounder amh in tissues and the gonads. The quantitative expression analysis results showed that it was highly expressed in the testis, especially in the testis at stages I - IV (P < 0.05). Also, amh was detected in Sertoli cells surrounding spermatogonia and peripheral seminiferous lobule of the testis with in situ hybridization (ISH) and immunohistochemistry (IHC). During the differentiation period, the amh expression in the testis of the tamoxifen treatment group (100 ppm) was higher than that in the ovary of the 17ß-estradiol (E2, 5 ppm) group, and the expression levels of amh during process of the male differentiation in the tamoxifen group were higher than those in the 17ɑ-methyltestosterone (MT, 5 ppm) group (P < 0.05). ISH results also exhibited that amh was expressed in the somatic cells that surrounded the germ cells of juvenile flounder similar to adult ones. Furthermore, the flounder gonads in the tamoxifen group maintained more germ cells and somatic cells than those in the MT group from 20 to 80 mm total length (TL). Especially, at 60 and 80 mm TL, the numbers of germ and somatic cells in the tamoxifen group were significantly higher than those in the MT group (P < 0.05). In summary, amh might initiate the process of testicular differentiation, and is involved in the early development and maintenance of testis.


Assuntos
Hormônio Antimülleriano/genética , Linguado/genética , Células de Sertoli/metabolismo , Animais , Hormônio Antimülleriano/metabolismo , Diferenciação Celular , Estradiol/farmacologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Gônadas/metabolismo , Hibridização In Situ/métodos , Masculino , Metiltestosterona/farmacologia , Ovário/metabolismo , Diferenciação Sexual/genética , Espermatogônias/metabolismo , Tamoxifeno/farmacologia , Testículo/metabolismo
10.
Gene ; 752: 144783, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32428699

RESUMO

RNA interference (RNAi), which employs double-strand RNA (dsRNA) or small interference RNA (siRNA), is a popular reverse genetic manipulation tool to study gene function. Presently, there is few reports on the implementation of RNAi on the insulin-like androgenic gland gene (IAG) in red swamp crayfish Procambarus clarkii. In this study, the effective sequence of siRNA and optimal injection dose were determined, and the effects of RNAi using dsRNA, siRNA, and long-term RNAi were investigated. The results showed that the doses of 0.5 and 1 µg/g of body weight of IAG-siRNA3 produced significantly better inhibition than 0.1 µg/g. qPCR assays showed that both dsRNA and siRNA silenced the IAG expression in five tissues (brain, ventral nerve cord, androgenic gland, testis, and vas deferens) in adult P. clarkii, with the effectiveness decreasing over time, inhibiting the production of spermatid. dsRNA exhibited a longer interference effect than siRNA in adults. For long-term interference (P. clarkii juveniles were injected 7 times with 1 µg/g of body weight of IAG-dsRNA), and found that the secondary sexual characteristics of juveniles were affected, while the control group developed normally. The results of this study could lay the foundation for crayfish sex reversal with IAG RNAi, and provide the reference for those studies in which the technique of RNAi was used.


Assuntos
Astacoidea/genética , Hormônios Gonadais/genética , Androgênios/metabolismo , Animais , Astacoidea/metabolismo , Hormônios Gonadais/metabolismo , Masculino , Interferência de RNA/fisiologia , RNA de Cadeia Dupla/metabolismo , RNA Interferente Pequeno/metabolismo , Diferenciação Sexual/genética , Testículo/metabolismo
11.
Gene ; 750: 144756, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32389707

RESUMO

Noncoding RNAs (ncRNAs), including long ncRNAs (lncRNAs), circular RNAs (circRNAs) and microRNAs (miRNAs) have been extensively studied in biological processes such as disease development, cell proliferation but remained unclear in sex differentiation in organisms. In this study, the transcriptome profiles were comparatively analyzed between male and female gonads in Mauremys mutica. A total of 8237 differentially expressed genes (DEGs), 9573 DE lncRNAs, 84 DE circRNAs and 665 DE miRNAs were identified between male and female gonads. Through gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) of the DE RNAs, it was revealed that the DE mRNAs were majorly involved in GO terms, such as 'reproduction', 'reproductive process' and the pathways of 'focal adhesion' and 'oocyte meiosis'. In addition, a co-expression network showed that the expression of gametogenesis and sex differentiation related genes, including dmrt3a, tdrd7, sox14, etc were closely associated with the levels of their corresponding ncRNAs. Intriguingly, the dmrt1 circRNA and its target mRNA were detected upregulated both in adult testis and male producing temperature (MPT) embryos. Our findings demonstrated the sexually dimorphic expression profiles of mRNAs and ncRNAs in turtle gonads, which will provide the index to find out the molecular mechanisms behind the sex differentiation in turtles, even in other environmental sex determination (ESD) species.


Assuntos
Caracteres Sexuais , Tartarugas/genética , Animais , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/genética , Ontologia Genética , Gônadas/metabolismo , Masculino , MicroRNAs/genética , RNA Circular/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , RNA não Traduzido/genética , Diferenciação Sexual , Transcriptoma/genética
12.
Chemosphere ; 256: 127105, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32450357

RESUMO

Previous studies have shown that waterborne fluoride exposure has adverse effects on the reproductive system of zebrafish. However, the underlying toxic mechanisms were still not clear. In the present study, female zebrafish were exposed to different concentrations of 0.787 (Control), 18.599, 36.832 mg/L of fluoride for 30 d and 60 d, and the effects of different doses of fluoride on ovary development, reproductive hormones, oogenesis, ROS content, antioxidant levels, and the expression of apoptosis-related genes and proteins in the ovaries of female zebrafish were analyzed. The results showed that ovarian weight and GSI were significantly decreased, FSH, LH and VTG levels were significantly reduced, the transcriptional profiles of oogenesis-related genes (tgfß1, bmp15, gdf9, mprα, mprß, ptg2ß) were remarkably altered, ROS levels was notably increased, the SOD, CAT, GPx activities and GSH content as well as their mRNA expressions were significantly decreased, MDA content was remarkably increased, the expressions of apoptosis-related genes and proteins (caspase3, caspase8, caspase9, Fas-L, Cytochrome C, Bax and Bcl-2) were significantly changed, the ratio of Bax/Bcl-2 protein levels were notably increased. Taken together, this study demonstrated that fluoride exposure significantly affected ovarian development, decreased the reproductive hormones, affected oogenesis, induced oxidative stress, caused apoptosis through both extrinsic and intrinsic pathways in ovary of zebrafish. Indicating that oogenesis, oxidative stress, and apoptosis were responsible for the impairment of ovarian development.


Assuntos
Fluoretos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Feminino , Oogênese/efeitos dos fármacos , Ovário/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Diferenciação Sexual , Peixe-Zebra/metabolismo
13.
Cell Mol Life Sci ; 77(21): 4223-4236, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32367192

RESUMO

The determination of sex is an important hallmark in the life cycle of organisms, in which the fate of gonads and then the individual sex are defined. In gonochoristic teleost fish, this process is characterized by a high plasticity, considering that in spite of genotypic sex many environmental factors can cause shifts from one to another molecular pathway, resulting in organisms with mismatching genotypic and phenotypic sexes. Interestingly, in most instances, both female-to-male or male-to-female sex-reversed individuals develop functional gonads with normal gametogenesis and respective progenies with full viability. The study of these mechanisms is being spread to other non-model species or to those inhabiting more extreme environmental conditions. Although water temperature is an important mechanism involved in sex determination, there are other environmental stressors affected by the climate change which are also implicated in stress response-induced masculinization in fish. In this regard, the brain has emerged as the transducer of the environment input that can influence the gonadal fate. Furthermore, the evaluation of other environmental stressors or their synergic effect on sex determination at conditions that simulate the natural environments is growing gradually. Within such scope, the concerns related to climate change impacts rely on the fact that many of biotic and abiotic parameters reported to affect sex ratios are expected to increase concomitantly as a result of increased greenhouse gas emissions and, particularly worrying, many of them are related to male bias in the populations, such as high temperature, hypoxia, and acidity. These environmental changes can also generate epigenetic changes in sex-related genes affecting their expression, with implications on sex differentiation not only of exposed individuals but also in following generations. The co-analysis of multi-stressors with potential inter- and transgenerational effects is essential to allow researchers to perform long-term predictions on climate change impacts in wild populations and for establishing highly accurate monitoring tools and suitable mitigation strategies.


Assuntos
Peixes/fisiologia , Processos de Determinação Sexual , Animais , Mudança Climática , Meio Ambiente , Epigênese Genética , Feminino , Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Diferenciação Sexual , Estresse Fisiológico
14.
Gene ; 745: 144651, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32259633

RESUMO

Sexual differentiation and ovotestis development are closely associated with cortisol levels, the principal indicator of stress, via the glucocorticoid receptor (GR) in teleosts. Thus, GR is regarded as a mediator to expound the relationship between social stress and gonad development. In the present study, two gr genes (gr1 and gr2) were cloned and analyzed from a protandrous hermaphroditic teleost, the yellowtail clownfish (Amphiprion clarkii). GR1 was found to display a conserved nine-amino-acid insert, WRARQNTDG, between two zinc finger domains. The phylogenetic tree of GR showed that yellowtail clownfish GR1 and GR2 are clustered to teleost GR1 and teleost GR2 separately, and differ from tetrapod GR. The result of real-time PCR revealed that high-level gr1 was mainly distributed in the cerebellum, hypothalamus and heart. The gr2 gene was abundant in the pituitary and liver of females and nonbreeders, while gr2 was mainly detected in the medulla oblongata and middle kidney of males. Moreover, GRs can be expressed in cultured eukaryotic cells and functionally interact with dexamethasone (exogenous glucocorticoid), thereby triggering downstream signaling pathways of different potentials. GR1 and GR2 can be activated by 10 nM dexamethasone treatment in HEK-293T cells. Notably, real-time PCR analysis among three social status groups demonstrated that gr2 expression was the highest in the hypothalamus of nonbreeders, but gr1 was no difference. We speculate that social stress would increase the expression of gr2 gene expression in the hypothalamus to inhibit sexual development. These data provide evidence of social stress involving reproductive regulation, which may help to elucidate the underlying mechanism of sex differentiation and change.


Assuntos
Proteínas de Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Perciformes/genética , Receptores de Glucocorticoides/genética , Diferenciação Sexual/genética , Animais , Dexametasona/farmacologia , Feminino , Proteínas de Peixes/metabolismo , Células HEK293 , Humanos , Masculino , Família Multigênica , Perciformes/metabolismo , Filogenia , Receptores de Glucocorticoides/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reprodução/genética , Transdução de Sinais/efeitos dos fármacos , Estresse Psicológico/genética , Dedos de Zinco/genética
15.
Aquat Toxicol ; 223: 105476, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32315829

RESUMO

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used pharmaceuticals to treat pain, fever and inflammation. NSAIDs are also known to have many side effects including adverse effects on reproduction in both humans and animals. As NSAIDs usage is not regulated they are frequently detected at high concentrations in the environment. In order to understand the effect of NSAIDs on zebrafish sex differentiation, we used seven different NSAIDs which were either Cox-1 selective, Cox-1 biased, non-selective or COX-2 selective. We show that at higher concentration, NSAIDs are toxic to zebrafish embryo as they lead to mortality and hatching delay. Gene expression analysis following short term exposure of NSAIDs led to downregulation of female specific genes including zp2, vtg2 foxl2 and wnt4. Long term exposure of larvae to environmentally relevant concentrations of Cox-2 selective and non-selective NSAIDs resulted in male-biased sex ratio which confirmed the qRT-PCR analysis. However, the Cox-1 selective acetylsalicylic acid and the Cox-1 biased ketoprofen did not alter sex ratio. The observed male-biased sex ratio could also be due to induction of apoptosis process as the genes including p21 and casp8 were significantly upregulated following exposure to the Cox-2 selective and the non-selective NSAIDs. The present study indicates that NSAIDs alter sex differentiation in zebrafish, primarily through inhibition of Cox-2. This study clearly demonstrates that the use of NSAIDs and their release into the aquatic environment should be carefully monitored to avoid adverse effects to the aquatic organisms.


Assuntos
Anti-Inflamatórios não Esteroides/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Diferenciação Sexual/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Desenvolvimento Embrionário/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Inflamação , Masculino , Diferenciação Sexual/genética , Peixe-Zebra/genética
16.
Zoolog Sci ; 37(2): 140-147, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32282145

RESUMO

To elucidate the role of dmrt1 in sex differentiation of a teleost fish Schizothorax kozlovi, the full-length sequences of its cDNA and promoter were cloned by rapid amplification of cDNA ends (RACE) and genome walking. The relative mRNA expression levels were determined by quantitative real-time PCR (RT-PCR). The 1095-bp dmrt1 cDNA was predicted to encode a protein of 264 amino acids. It was expressed only in the gonads, and the expression was 17-times higher in the testis than in the ovary. The 1215-bp promoter sequence of dmrt1 was cloned and analyzed to detect sex-related differences in its methylation levels. A significant negative relationship between the dmrt1 expression and CpG methylation of its promoter were found in the testes and ovaries of S. kozlovi. Significant differences in dmrt1 expression levels were also found between the larval and juvenile stages. No significant differences in expression were found during the entire larval stage, and in the individuals among three different temperature groups (10°C, 14°C, and 18°C). Considering that the sex of sampled larval fish cannot be distinguished, correlations between dmrt1 expression and effects of temperature on sex differentiation in S. kozlovi need further study.


Assuntos
Ilhas de CpG/fisiologia , Cyprinidae/genética , Diferenciação Sexual/genética , Sequência de Aminoácidos , Animais , Cyprinidae/crescimento & desenvolvimento , DNA Complementar/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Larva/genética , Larva/metabolismo , Masculino , Metilação , Ovário/metabolismo , Regiões Promotoras Genéticas/fisiologia , RNA Mensageiro , Análise de Sequência de DNA , Processos de Determinação Sexual/genética , Temperatura , Testículo/metabolismo
17.
Ann Endocrinol (Paris) ; 81(2-3): 83-88, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32340851

RESUMO

Gonad differentiation depends on a set of cellular and hormonal signals interacting in a specific order, with very precise windows of action, to contribute to the establishment of the genital tract and a male or female phenotype. Research initially focused on the stages of gonad differentiation toward testis, in particular following the identification in 1990 of the SRY factor on chromosome Y. The mechanisms involved in gonad differentiation toward ovary took longer to identify. Thanks to patients with different sexual development (DSD) and animal knock-out models, description of the cascades involved in the activation and maintenance of ovarian development has progressed considerably in recent years.


Assuntos
Gônadas/fisiologia , Ovário/fisiologia , Processos de Determinação Sexual/fisiologia , Diferenciação Sexual/genética , Animais , Diferenciação Celular/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Gônadas/embriologia , Gônadas/crescimento & desenvolvimento , Humanos , Masculino , Ovário/embriologia , Ovário/crescimento & desenvolvimento , Fenótipo , Desenvolvimento Sexual/genética , Desenvolvimento Sexual/fisiologia
18.
Am J Physiol Endocrinol Metab ; 318(6): E901-E919, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32286880

RESUMO

Lack of GABAB receptors in GABAB1 knockout mice decreases neonatal ARC kisspeptin 1 (Kiss1) expression in the arcuate nucleus of the hypothalamus (ARC) in females, which show impaired reproduction as adults. Our aim was to selectively impair GABAB signaling during a short postnatal period to evaluate its impact on the reproductive system. Neonatal male and female mice were injected with the GABAB antagonist CGP 55845 (CGP, 1 mg/kg body wt sc) or saline from postnatal day 2 (PND2) to PND6, three times per day (8 AM, 1 PM, and 6 PM). One group was killed on PND6 for collection of blood samples (hormones by radioimmunoassay), brains for gene expression in the anteroventral periventricular nucleus-periventricular nucleus continuum (AVPV/PeN), and ARC micropunches [quantitative PCR (qPCR)] and gonads for qPCR, hormone contents, and histology. A second group of mice was injected with CGP (1 mg/kg body wt sc) or saline from PND2 to PND6, three times per day (8 AM, 1 PM, and 6 PM), and left to grow to adulthood. We measured body weight during development and parameters of sexual differentiation, puberty onset, and estrous cycles. Adult mice were killed, and trunk blood (hormones), brains for qPCR, and gonads for qPCR and hormone contents were obtained. Our most important findings on PND6 include the CGP-induced decrease in ARC Kiss1 and increase in neurokinin B (Tac2) in both sexes; the decrease in AVPV/PeN tyrosine hydroxylase (Th) only in females; the increase in gonad estradiol content in both sexes; and the increase in primordial follicles and decrease in primary and secondary follicles. Neonatally CGP-treated adults showed decreased ARC Kiss1 and ARC gonadotropin-releasing hormone (Gnrh1) and increased ARC glutamic acid decarboxylase 67 (Gad1) only in males; increased ARC GABAB receptor subunit 1 (Gabbr1) in both sexes; and decreased AVPV/PeN Th only in females. We demonstrate that ARC Kiss1 expression is chronically downregulated in males and that the normal sex difference in AVPV/PeN Th expression is abolished. In conclusion, neonatal GABAergic input through GABAB receptors shapes gene expression of factors critical to reproduction.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Hipotálamo Anterior/metabolismo , Receptores de GABA-B/metabolismo , Animais , Animais Recém-Nascidos , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Estradiol/metabolismo , Feminino , Hormônio Foliculoestimulante/metabolismo , Antagonistas de Receptores de GABA-B/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo Anterior/efeitos dos fármacos , Kisspeptinas/genética , Kisspeptinas/metabolismo , Hormônio Luteinizante/metabolismo , Masculino , Camundongos , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ácidos Fosfínicos/farmacologia , Propanolaminas/farmacologia , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Puberdade/efeitos dos fármacos , Puberdade/genética , Receptores Estrogênicos/genética , Receptores Estrogênicos/metabolismo , Receptores de GABA-B/genética , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Reprodução/efeitos dos fármacos , Reprodução/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Diferenciação Sexual/efeitos dos fármacos , Diferenciação Sexual/genética , Taquicininas/genética , Taquicininas/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testosterona/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
19.
J Morphol ; 281(4-5): 491-499, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32198946

RESUMO

Arapaima gigas is a giant air-breathing and bony tongue fish from the Amazon basin and a promising species for aquaculture. A. gigas farming industry is still not established because of the lack of information on its reproductive physiology. Reproduction in captivity cannot be manipulated or stimulated, and the identification of males and females in a broodstock is not easy. We aimed to reveal the morphological sex differentiation of pirarucu as studies involving gonad development are essential to understanding the reproductive physiology of any species. We performed histological analysis on the whole body and extracted the gonads of 150 juveniles. The first sign of ovary differentiation is the sex-specific rearrangement of the germ cells. In 9 cm total length females, the germ cells group into nests and are restricted to the lateral face of the gonad, in close contact with the abdomen wall. With further development, this region invaginates and that later develops into ovigerous lamellae. Meiosis starts soon after ovary differentiation. In males, the germ cells are scattered along the elongated differentiating testis at first, and later become more restricted to the central region where the spermatogonial cysts start to develop. Somatic and germ cells are jointly involved in the cellular reorganization during gonadal differentiation, specifically when the germ cells begin to establish new associations during the development of both the germinal epithelium and stroma. RESEARCH HIGHLIGHTS: In Arapaima gigas, the ovary differentiation occurs in 9 cm TL females and it is marked by the rearrangement of germ and somatic cells; and the germ cells entering meiosis with no formation of ovarian cavity; testis differentiation occurs later and meiosis does not start in males smaller than 80 cm TL.


Assuntos
Peixes/anatomia & histologia , Gônadas/anatomia & histologia , Diferenciação Sexual , Animais , Diferenciação Celular , Feminino , Peixes/crescimento & desenvolvimento , Peixes/fisiologia , Masculino , Ovário/anatomia & histologia , Ovário/citologia , Testículo/anatomia & histologia , Testículo/crescimento & desenvolvimento , Vitelogênese
20.
Artigo em Inglês | MEDLINE | ID: mdl-32017989

RESUMO

Steroid hormones have been proven as a key drive of sex change in sequentially hermaphroditic organisms. However, the upstream mechanism of sex steroid hormones regulation that affect sex change remain unknown. The main glucocorticoid in teleost fish is cortisol, which both regulates steroidogenesis and has antistress action. Thus, cortisol might be one of the prime factors in sex change. In this study, the glucocorticoid-induced leucine zipper (GILZ) gene, was proven to have a dramatic effect in orange-spotted groupers (Epinephelus coioides) during sex change at the early stage of gonadal transition. The specific action of the GILZ protein is at the pouch-shaped proliferative spermatogonia instead of the degenerative oocyte at the onset of sex change. Immunohistochemical (IHC) evidence revealed that GILZ performs intensively at undifferentiated spermatogonia in the early testis stage. These results imply that cortisol provokes a rise of GILZ through regulation caused by steroid hormones leading to sex change.


Assuntos
Bass/metabolismo , Proteínas de Peixes/metabolismo , Zíper de Leucina/fisiologia , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Bass/genética , Bass/crescimento & desenvolvimento , Feminino , Proteínas de Peixes/biossíntese , Proteínas de Peixes/genética , Gônadas/crescimento & desenvolvimento , Gônadas/metabolismo , Organismos Hermafroditas , Masculino , Filogenia , Homologia de Sequência de Aminoácidos , Diferenciação Sexual/fisiologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
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