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1.
Gene ; 718: 144049, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31430520

RESUMO

The role of epigenetics in development has garnered attention in recent years due to their ability to modulate the embryonic developmental gene expression in response to the environmental cues. The epigenetic mechanisms - DNA methylation, histone modification, and non-coding RNAs have a unique impact on vertebrate development. Zebrafish, a model vertebrate organism is being used widely in developmental studies due to their high fecundability and rapid organogenesis. With increased studies on various aspects of epigenetics in development, this review gives a glimpse of the major epigenetic modifications and their role in zebrafish development. In this review, the basic mechanism behind each modification followed by their status in zebrafish has been reviewed. Further, recent advancements in the epigenetic aspect of zebrafish development have been discussed.


Assuntos
Metilação de DNA/fisiologia , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/fisiologia , Epigênese Genética/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Peixe-Zebra/embriologia , Animais , Histonas/genética , Histonas/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Peixe-Zebra/genética
2.
BMC Vet Res ; 15(1): 203, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31200703

RESUMO

BACKGROUND: Prostaglandin F2α (PGF2α) is an important component for the physiology of female reproductive processes. In the literature, the data pertaining to the synthesis and action of PGF2α in early embryonic bovine development are limited. In our study, we used the bovine in vitro culture model based on the time of first cleavage to determine the mRNA expression and immunolocalization of PGF2α synthase and its receptor in bovine embryos from the 2-cell stage to the hatched blastocyst stage. We also evaluated PGF2α production at 2, 5 and 7 days of in vitro culture. RESULTS: We found a significantly higher proportion of blastocysts obtained from the early-cleaved embryos than from the late-cleaved embryos (37.7% vs. 26.1% respectively, P < 0.05). The PGFS mRNA expression was significantly higher in the late-cleaved group than in the early-cleaved group at the 2-, 4- and 16-cell stages (P < 0.05). For PTGFR, we observed that within the late-cleaved group, the mRNA abundance was significantly higher in embryos at the 2- and 16-cell stages than in embryos at the 4- and 8-cell stages (P < 0.05). We observed that PTGFR mRNA expression was significantly higher in the 2- and 16-cell embryos in the late-cleaved group than that in the early-cleaved group embryos (P < 0.05). Among the blastocysts, the PGFS and PTGFR expression levels showed a trend towards higher mRNA expression in the late-cleaved group than in the early-cleaved group. Analysis of PGF2α production showed that within the early-cleaved group, the content of PGF2α in the in vitro culture medium was significantly higher on day 7 than it was on day 2 (P < 0.05). CONCLUSIONS: The mRNA expression levels of PGF2α synthase and its receptor depend on the developmental stage and the embryo quality. Analyses of PGFS and PTGFR expression in bovine blastocysts and of PGF2α embryo production suggest that prostaglandin F2α can act in an autocrine and paracrine manner in bovine in vitro-produced preimplantation embryos. Moreover, the tendency of PTGFR and PGFS mRNA expression to be upregulated in embryos with low developmental potential can indicate a compensation mechanism related to high PGFS and PTGFR mRNA expression levels in low-quality embryos.


Assuntos
Blastocisto/fisiologia , Bovinos/fisiologia , Prostaglandinas F/metabolismo , Receptores de Prostaglandina/metabolismo , Animais , Blastocisto/metabolismo , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/fisiologia , Prostaglandina-Endoperóxido Sintases/genética , Prostaglandina-Endoperóxido Sintases/metabolismo , RNA Mensageiro/metabolismo , Receptores de Prostaglandina/genética
3.
Cochrane Database Syst Rev ; 5: CD011320, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-31140578

RESUMO

BACKGROUND: Embryo incubation and assessment is a vital step in assisted reproductive technology (ART). Traditionally, embryo assessment has been achieved by removing embryos from a conventional incubator daily for quality assessment by an embryologist, under a microscope. In recent years time-lapse systems (TLS) have been developed which can take digital images of embryos at frequent time intervals. This allows embryologists, with or without the assistance of embryo selection software, to assess the quality of the embryos without physically removing them from the incubator.The potential advantages of a TLS include the ability to maintain a stable culture environment, therefore limiting the exposure of embryos to changes in gas composition, temperature, and movement. A TLS has the potential advantage of improving embryo selection for ART treatment by utilising additional information gained through continuously monitoring embryo development. Use of a TLS often adds significant extra cost to ART treatment. OBJECTIVES: To determine the effect of a TLS compared to conventional embryo incubation and assessment on clinical outcomes in couples undergoing ART. SEARCH METHODS: We used standard methodology recommended by Cochrane. We searched the Cochrane Gynaecology and Fertility (CGF) Group Trials Register, CENTRAL, MEDLINE, Embase, CINAHL, and two trials registers on 7 January 2019 and checked references of appropriate papers. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing TLS, with or without embryo selection software, versus conventional incubation with morphological assessment; and TLS with embryo selection software versus TLS without embryo selection software among couples undergoing ART. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures recommended by Cochrane. The primary review outcomes were live birth or ongoing pregnancy, miscarriage and stillbirth, and cumulative live birth or ongoing pregnancy rate. The secondary outcomes were clinical pregnancy and cumulative clinical pregnancy. We assessed the quality of the evidence using GRADE methodology. We made the following comparisons.TLS with conventional morphological assessment of still TLS images versus conventional incubation and assessmentTLS utilising embryo selection software versus TLS with conventional morphological assessment of still TLS images TLS utilising embryo selection software versus conventional incubation and assessment MAIN RESULTS: We included nine RCTs (N = 2955 infertile couples). The quality of the evidence ranged from very low to low. The main limitations were high risk of bias in the included studies, imprecision, indirectness, and inconsistency. There were no data on cumulative live birth or ongoing pregnancy rate or cumulative clinical pregnancy rate.TLS with conventional morphological assessment of still TLS images versus conventional incubation and assessmentIt is unclear whether there is any difference between interventions in rates of live birth or ongoing pregnancy (odds ratio (OR) 0.91, 95% confidence interval (CI) 0.67 to 1.23, 3 RCTs, N = 826, I2 = 33%, low-quality evidence) or in miscarriage rates (OR 1.90, 95% CI 0.99 to 3.61, 3 RCTs, N = 826, I2 = 0%, low-quality evidence). The evidence suggests that if the rate of live birth or ongoing pregnancy associated with conventional incubation and assessment is 35%, the rate with the use of TLS with conventional morphological assessment of still TLS images would be between 27% and 40%, and if the miscarriage rate with conventional incubation is 4%, the rate associated with conventional morphological assessment of still TLS images would be between 4% and 14%. It is unclear whether there is a difference between the interventions in rates of stillbirth (OR 1.00, 95% CI 0.13 to 7.49, 1 RCT, N = 76, low-quality evidence) or clinical pregnancy (OR 1.06, 95% CI 0.79 to 1.41, 4 RCTs, N = 875, I2 = 0%, low-quality evidence).TLS utilising embryo selection software versus TLS with conventional morphological assessment of still TLS imagesAll findings for this comparison were very uncertain due to the very low-quality of the evidence. No data were available on live birth, but one RCT reported ongoing pregnancy. It is unclear whether there is any difference between the interventions in rates of ongoing pregnancy (OR 0.61, 95% CI 0.32 to 1.20, 1 RCT, N = 163); miscarriage (OR 1.39, 95% CI 0.64 to 3.01, 2 RCTs, N = 463, I2 = 0%); or clinical pregnancy (OR 0.97, 95% CI 0.67 to 1.42, 2 RCTs, N = 463, I2 = 0%). The evidence suggests that if the rate of ongoing pregnancy associated with TLS with conventional morphological assessment of still TLS images is 47%, the rate associated with TLS utilising embryo selection software would be between 22% and 52%, and if the miscarriage rate associated with conventional morphological assessment of still TLS images is 5%, the rate associated with TLS utilising embryo selection software would be between 4% and 15%. No studies reported stillbirth.TLS utilising embryo selection software versus conventional incubation and assessmentThe findings for this comparison were also very uncertain due to the very low quality of the evidence. It is unclear whether there is any difference between the interventions in rates of live birth (OR 1.12, 95% CI 0.92 to 1.36, 3 RCTs, N = 1617, I2 = 84%). There was very low-quality evidence that TLS might reduce miscarriage rates (OR 0.63, 95% CI 0.45 to 0.89, 3 RCTs, N = 1617, I2 = 0%). It is unclear whether there is any difference between the interventions in rates of clinical pregnancy (OR 0.95, 95% CI 0.78 to 1.16, 3 RCTs, N = 1617, I2 = 89%). The evidence suggests that if the rate of live birth associated with conventional incubation and assessment is 48%, the rate with TLS utilising embryo selection software would be between 46% and 55%, and if the miscarriage rate with conventional incubation and assessment is 11%, the rate associated with TLS would be between 5% and 10%. No stillbirths occurred in the only study reporting this outcome. AUTHORS' CONCLUSIONS: There is insufficient good-quality evidence of differences in live birth or ongoing pregnancy, miscarriage and stillbirth, or clinical pregnancy to choose between TLS, with or without embryo selection software, and conventional incubation. As the evidence is of low or very low-quality, our findings should be interpreted with caution.


Assuntos
Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/fisiologia , Técnicas de Reprodução Assistida , Implantação do Embrião , Feminino , Humanos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Br Poult Sci ; 60(4): 395-403, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31132872

RESUMO

1. In this study, geese (Anas cygnoides) embryonic pituitary cells were cultured in vitro to determine if glucocorticoids could induce growth hormone (GH) expression and to investigate the molecular mechanisms involved in this process. 2. On embryonic day 15 (e15) and e20 the pituitary cells were treated with corticosterone (CORT), membrane impermeable bovine serum albumin-conjugate corticosterone (CORT-BSA), dexamethasone (DEX), and a glucocorticoid receptor (GR) antagonist (RU486) to detect responsiveness of somatotrophs to glucocorticoids. 3. Treatment with CORT, CORT-BSA, and DEX for as little as 6 h increased the percentage of GH-positive cells (P < 0.01) and increased GH mRNA expression (P < 0.01) in e15 goose pituitary cells compared to the control. CORT significantly increased the level of GH protein secreted from cultured e15 goose embryonic pituitary cells, and CORT-BSA increased GH secretion from e20 goose embryonic pituitary cells. 4. A significant increase was observed in the glucocorticoid receptor in GR transcription levels (P < 0.01) with CORT, CORT-BSA, and DEX treatment. Furthermore, the CORT-stimulated GH mRNA expression was completely negated by pre-treatment with RU486. 5. These findings demonstrate that glucocorticoids can stimulate somatotroph differentiation in vitro, as characterised by enhanced GH protein secretion andmRNA expression in cultured geese embryonic pituitary cells. The membrane GR was involved in pituitary somatotroph differentiation induced by glucocorticoids during the embryonic development of geese.


Assuntos
Diferenciação Celular/fisiologia , Corticosterona/farmacologia , Cortisona/farmacologia , Dexametasona/farmacologia , Gansos/fisiologia , Receptores de Glucocorticoides/metabolismo , Soroalbumina Bovina/farmacologia , Somatotrofos/fisiologia , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Células Cultivadas , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/fisiologia , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/fisiologia , Gansos/genética , Antagonistas de Hormônios/farmacologia , Mifepristona/farmacologia , Hipófise/fisiologia , RNA Mensageiro/metabolismo
5.
BMC Vet Res ; 15(1): 166, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31122240

RESUMO

BACKGROUND: In broilers chickens, the molecular bases for promoting muscle development and growth requires further investigation. Therefore, the current study aimed to investigate the effects of daily thermal manipulation (TM) during embryonic days (ED) 12 to 18 on body, carcass and internal organ weights as well as on the expression of muscle growth markers genes during late embryogenesis and post-hatch days. 1500 fertile Cobb eggs were divided into five groups. The first group was a control group and incubated at 37.8°C. The other four groups were thermally manipulated (TM) and exposed to 38.5°C (TM1), 39°C (TM2), 39.5°C (TM3) and 40°C (TM4) daily for 18 h, respectively, with a relative humidity of 56%. Body weights (BW) from ED 12 to 18 and on post-hatch days 1, 2, 3, 4, 5, 6, 7, 14, 21, 28 and 35 were recorded. mRNA expression levels of muscle growth factor genes (IGF-1 and GH) and muscle marker genes (Myogenic Differentiation Antigen; MyoD), Myogenin, Pax7, and PCNA) during ED 12 to 18 and on post-hatch days 1, 3, 5, 7, 14 were analyzed. On post-hatch day 35, the carcass and internal organ weights have been also evaluated. RESULTS: TM during certain days of embryogenesis (ED 12 to 18) did not affect the BW of broilers during their embryonic lives. However, TM, particularly TM1 and TM2, significantly increased BW, carcass and internal weights of hatched chicks near to the marketing age (post-hatch days 28 and 35). Most of TM protocols induced up-regulation of muscle growth factor genes (IGF-1 and GH) and muscle marker genes (MyoD, Myogenin, Pax7, and PCNA) during embryonic life (ED 12 to 18) and on post-hatch days. CONCLUSION: Among the various TM conditions, it seems that,TM1 and TM2 induced a significant increase in BW, carcass and internal weights of hatched chicks near to the marketing age. This increase in BW induced presumably via up-regulation of muscle growth factor genes and muscle growth markers genes during embryonic life (ED 12 to 18) and on post-hatch days. Both protocols (TM1 and TM2) can be used in real-world applications of poultry industry for maximum benefit.


Assuntos
Galinhas/fisiologia , Temperatura Alta , Desenvolvimento Muscular/fisiologia , Animais , Peso Corporal/fisiologia , Embrião de Galinha , Galinhas/genética , Galinhas/crescimento & desenvolvimento , Desenvolvimento Embrionário/fisiologia , Marcadores Genéticos , Desenvolvimento Muscular/genética , Tamanho do Órgão/fisiologia , RNA Mensageiro
6.
Acta Histochem ; 121(5): 604-610, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31113654

RESUMO

Endogenous gaseous transmitters (nitric oxide, carbon monoxide, and hydrogen sulphide) form a special neuromodulation system mediating the development and modification of nerve centers. Here, we examined the localization of key gaseous transmitter enzymes: cystathionine ß-synthetase (CBS), cystathionine γ-lyase (CSE), heme oxygenase 2 (HO-2), and constitutive NO synthase (nNOS) in the fetal human retina at different stages of development. The number of CBS- and CSE-positive photoreceptors and intermediate retinal neurons was high in trimester I and gradually decreased to the end of trimester III. The number of HO-2-positive cells followed the same trend. The number of nNOS-positive intermediate retinal neurons and neurons within the ganglion cell layer showed the opposite dynamics with the peak in trimester III. The results are interpreted in terms of the role of gaseous transmitters in retinogenesis and cytoprotection.


Assuntos
Monóxido de Carbono/metabolismo , Gasotransmissores/metabolismo , Sulfeto de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Retina/embriologia , Retina/enzimologia , Cistationina beta-Sintase/metabolismo , Cistationina gama-Liase/metabolismo , Desenvolvimento Embrionário/fisiologia , Heme Oxigenase (Desciclizante)/metabolismo , Humanos , Imuno-Histoquímica , Óxido Nítrico Sintase/metabolismo
7.
Nat Commun ; 10(1): 2219, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101825

RESUMO

A long-standing question in the field of embryogenesis is how the zygotic genome is precisely activated by maternal factors, allowing normal early embryonic development. We have previously shown that N6-methyladenine (6mA) DNA modification is highly dynamic in early Drosophila embryos and forms an epigenetic mark. However, little is known about how 6mA-formed epigenetic information is decoded. Here we report that the Fox-family protein Jumu binds 6mA-marked DNA and acts as a maternal factor to regulate the maternal-to-zygotic transition. We find that zelda encoding the pioneer factor Zelda is marked by 6mA. Our genetic assays suggest that Jumu controls the proper zygotic genome activation (ZGA) in early embryos, at least in part, by regulating zelda expression. Thus, our findings not only support that the 6mA-formed epigenetic marks can be read by specific transcription factors, but also uncover a mechanism by which the Jumu regulates ZGA partially through Zelda in early embryos.


Assuntos
DNA/metabolismo , Proteínas de Drosophila/metabolismo , Desenvolvimento Embrionário/fisiologia , Fatores de Transcrição/metabolismo , Zigoto/metabolismo , Adenina/análogos & derivados , Adenina/metabolismo , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiologia , Embrião não Mamífero , Epigênese Genética/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Técnicas de Silenciamento de Genes , Genoma de Inseto , Masculino , Fatores de Transcrição/genética
8.
Int J Mol Sci ; 20(7)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987365

RESUMO

The somatic embryogenesis (SE) process of plants, as one of the typical responses to abiotic stresses with hormone, occurs through the dynamic expression of different proteins that constitute a complex regulatory network in biological activities and promotes plant totipotency. Plant SE includes two critical stages: primary embryogenic calli redifferentiation and somatic embryos development initiation, which leads to totipotency. The isobaric labels tandem mass tags (TMT) large-scale and quantitative proteomics technique was used to identify the dynamic protein expression changes in nonembryogenic calli (NEC), primary embryogenic calli (PEC) and globular embryos (GEs) of cotton. A total of 9369 proteins (6730 quantified) were identified; 805, 295 and 1242 differentially accumulated proteins (DAPs) were identified in PEC versus NEC, GEs versus PEC and GEs versus NEC, respectively. Eight hundred and five differentially abundant proteins were identified, 309 of which were upregulated and 496 down regulated in PEC compared with NEC. Of the 295 DAPs identified between GEs and PEC, 174 and 121 proteins were up- and down regulated, respectively. Of 1242 differentially abundant proteins, 584 and 658 proteins were up- and down regulated, respectively, in GEs versus NEC. We have also complemented the authenticity and accuracy of the proteomic analysis. Systematic analysis indicated that peroxidase, photosynthesis, environment stresses response processes, nitrogen metabolism, phytohormone response/signal transduction, transcription/posttranscription and modification were involved in somatic embryogenesis. The results generated in this study demonstrate a proteomic molecular basis and provide a valuable foundation for further investigation of the roles of DAPs in the process of SE transdifferentiation during cotton totipotency.


Assuntos
Transdiferenciação Celular/fisiologia , Gossypium/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Transdiferenciação Celular/genética , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Gossypium/embriologia , Gossypium/genética , Proteínas de Plantas/genética , Proteômica
9.
Methods Mol Biol ; 1976: 71-82, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30977066

RESUMO

In ovo electroporation enables transfection of non-viral plasmid DNA and/or morpholinos to fluorescently label and/or perturb gene function in cells of interest. However, targeted electroporation into specific subregions of the embryo can be challenging due to placement and size limitations of the electrodes. Here we describe the basic techniques for in ovo electroporation in the chick embryo and suggest parameters to electroporate cells within different target tissues that with some modifications may be applicable to a wide range of developmental stages and other embryo model organisms.


Assuntos
Eletroporação/métodos , Morfolinos/metabolismo , Plasmídeos/genética , Animais , Embrião de Galinha , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento
10.
Nat Commun ; 10(1): 1606, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30962435

RESUMO

Vascular endothelial growth factor (VEGF) regulates vasculogenesis by using its tyrosine kinase receptors. However, little is known about whether Sec14-like phosphatidylinositol transfer proteins (PTP) are involved in this process. Here, we show that zebrafish sec14l3, one of the family members, specifically participates in artery and vein formation via regulating angioblasts and subsequent venous progenitors' migration during vasculogenesis. Vascular defects caused by sec14l3 depletion are partially rescued by restoration of VEGFR2 signaling at the receptor or downstream effector level. Biochemical analyses show that Sec14l3/SEC14L2 physically bind to VEGFR2 and prevent it from dephosphorylation specifically at the Y1175 site by peri-membrane tyrosine phosphatase PTP1B, therefore potentiating VEGFR2 signaling activation. Meanwhile, Sec14l3 and SEC14L2 interact with RAB5A/4A and facilitate the formation of their GTP-bound states, which might be critical for VEGFR2 endocytic trafficking. Thus, we conclude that Sec14l3 controls vasculogenesis in zebrafish via the regulation of VEGFR2 activation.


Assuntos
Neovascularização Fisiológica/fisiologia , Proteínas de Transferência de Fosfolipídeos/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Animais , Animais Geneticamente Modificados , Proteínas de Transporte/metabolismo , Embrião não Mamífero , Desenvolvimento Embrionário/fisiologia , Técnicas de Silenciamento de Genes , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Lipoproteínas/metabolismo , Proteínas de Transferência de Fosfolipídeos/genética , Transdução de Sinais/fisiologia , Transativadores/metabolismo , Proteínas rab5 de Ligação ao GTP/metabolismo
11.
Biochem Soc Trans ; 47(2): 713-724, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30952803

RESUMO

How developmental gene expression is activated, co-ordinated and maintained is one of the biggest questions in developmental biology. While transcription factors lead the way in directing developmental gene expression, their accessibility to the correct repertoire of genes can depend on other factors such as DNA methylation, the presence of particular histone variants and post-translational modifications of histones. Collectively, factors that modify DNA or affect its packaging and accessibility contribute to a chromatin landscape that helps to control the timely expression of developmental genes. Zebrafish, perhaps better known for their strength as a model of embryology and organogenesis during development, are coming to the fore as a powerful model for interpreting the role played by chromatin in gene expression. Several recent advances have shown that zebrafish exhibit both similarities and differences to other models (and humans) in the way that they employ chromatin mechanisms of gene regulation. Here, I review how chromatin influences developmental transcriptional programmes during early zebrafish development, patterning and organogenesis. Lastly, I briefly highlight the importance of zebrafish chromatin research towards the understanding of human disease and transgenerational inheritance.


Assuntos
Cromatina/metabolismo , Animais , Cromatina/genética , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Epigenômica/métodos , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Peixe-Zebra
12.
Ecotoxicol Environ Saf ; 179: 151-159, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31035249

RESUMO

Tetrabromobisphenol A bis(2,3-dibromopropyl ether) (TBBPA-BDBPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTPBE) are both brominated flame retardants (BFRs) that have been detected in birds; however, their potential biological effects are largely unknown. We assessed the effects of embryonic exposure to TBBPA-BDBPE and BTBPE in a model avian predator, the American kestrel (Falco sparverius). Fertile eggs from a captive population of kestrels were injected on embryonic day 5 (ED5) with a vehicle control or one of three doses within the range of concentrations that have been detected in biota (nominal concentrations of 0, 10, 50 or 100 ng/g egg; measured concentrations 0, 3.0, 13.7 or 33.5 ng TBBPA-BDBPE/g egg and 0, 5.3, 26.8 or 58.1 ng BTBPE/g egg). Eggs were artificially incubated until hatching (ED28), at which point blood and tissues were collected to measure morphological and physiological endpoints, including organ somatic indices, circulating and glandular thyroid hormone concentrations, thyroid gland histology, hepatic deiodinase activity, and markers of oxidative stress. Neither compound had any effects on embryo survival through 90% of the incubation period or on hatching success, body mass, organ size, or oxidative stress of hatchlings. There was evidence of sex-specific effects in the thyroid system responses to the BTBPE exposures, with type 2 deiodinase (D2) activity decreasing at higher doses in female, but not in male hatchlings, suggesting that females may be more sensitive to BTBPE. However, there were no effects of TBBPA-BDBPE on the thyroid system in kestrels. For the BTPBE study, a subset of high-dose eggs was collected throughout the incubation period to measure changes in BTBPE concentrations. There was no decrease in BTBPE over the incubation period, suggesting that BTBPE is slowly metabolized by kestrel embryos throughout their ∼28-d development. These two compounds, therefore, do not appear to be particularly toxic to embryos of the American kestrel.


Assuntos
Bromobenzenos/toxicidade , Desenvolvimento Embrionário/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Falconiformes/crescimento & desenvolvimento , Retardadores de Chama/toxicidade , Óvulo/efeitos dos fármacos , Bifenil Polibromatos/toxicidade , Animais , Relação Dose-Resposta a Droga , Desenvolvimento Embrionário/fisiologia , Falconiformes/metabolismo , Feminino , Iodeto Peroxidase/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Óvulo/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Hormônios Tireóideos/metabolismo
13.
Nat Commun ; 10(1): 1839, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015398

RESUMO

Hematopoietic stem and progenitor cells (HSPCs) are capable of producing all mature blood lineages, as well as maintaining the self-renewal ability throughout life. The hairy-like organelle, cilium, is present in most types of vertebrate cells, and plays important roles in various biological processes. However, it is unclear whether and how cilia regulate HSPC development in vertebrates. Here, we show that cilia-specific genes, involved in primary cilia formation and function, are required for HSPC development, especially in hemogenic endothelium (HE) specification in zebrafish embryos. Blocking primary cilia formation or function by genetic or chemical manipulations impairs HSPC development. Mechanistically, we uncover that primary cilia in endothelial cells transduce Notch signal to the earliest HE for proper HSPC specification during embryogenesis. Altogether, our findings reveal a pivotal role of endothelial primary cilia in HSPC development, and may shed lights into in vitro directed differentiation of HSPCs.


Assuntos
Cílios/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Receptores Notch/metabolismo , Transdução de Sinais/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Cílios/genética , Embrião não Mamífero , Desenvolvimento Embrionário/fisiologia , Hemangioblastos/citologia , Hemangioblastos/metabolismo , Hematopoese/fisiologia , Modelos Animais , Peixe-Zebra/fisiologia
14.
Poult Sci ; 98(7): 2977-2988, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30915476

RESUMO

Blue-breasted quail has been recognized as a potential model animal. The aim of this study is to investigate the low-temperature-induced embryonic diapause in blue-breasted quail. To this end, the early embryonic staging in blue-breasted quail was briefly described and various incubation temperatures were tested. While the embryonic diapause in early blue-breasted quail embryos can be induced when the eggs were stored at 21°C, a lower temperature such as 16°C yielded a significantly better hatchability (P = 0.0231). Additionally, prolonged storage duration from 3, 7 to 14 d significantly reduced the hatchability (P < 0.0001). Visual examination on the unhatched eggs revealed that reduced hatchability in prolonged storage was significantly correlated with embryonic mortality during the first half of incubation period (R2 = 0.9999, P = 0.0055). High-throughput RNA sequencing with de novo assembly showed that a gene network cluster consisted of ND4, ND5, ND6, and COX3, which are components of mitochondrial respiratory complexes, was down-regulated in the cold-stored embryos, while a stress-responsive gene network cluster consisted of JUN, ATF3, and DUSP1 was up-regulated. Accordingly, cell death in the blastoderm was significantly increased as the storage duration prolonged from 3 to 10 d. Taken together, our study provided basic information on the temperature-induced embryonic diapause in blue-breasted quail. Furthermore, transcriptomic analysis sheds light for the molecular basis on how blastoderm cells respond to the prolonged cold-stress and stay diapause.


Assuntos
Temperatura Baixa , Coturnix/embriologia , Diapausa/fisiologia , Desenvolvimento Embrionário/fisiologia , Animais , Coturnix/genética , Coturnix/metabolismo , Diapausa/genética , Embrião não Mamífero/embriologia , Óvulo/fisiologia , Análise de Sequência de RNA , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia
15.
Methods Mol Biol ; 1920: 393-406, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30737705

RESUMO

The division patterns of early invertebrate and vertebrate embryos are key to the specification of cell fates and embryo body axes. We here describe a generic computational modeling method to quantitatively test mechanisms which specify successive division position and orientation of eggs and early blastomeres in 3D. This approach should serve to motivate and guide future experimental work on the mechanisms controlling early embryo morphogenesis.


Assuntos
Fase de Clivagem do Zigoto , Desenvolvimento Embrionário/fisiologia , Modelos Biológicos , Diferenciação Celular , Divisão Celular , Técnicas de Cultura Embrionária , Imagem Tridimensional , Microscopia Confocal
16.
J Reprod Dev ; 65(2): 183-190, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-30745496

RESUMO

We examined whether the use of in vivo-matured oocytes, collected by ovum pick-up (OPU) from superstimulated Japanese Black cows, can improve the productivity and quality of in vitro produced embryos. The cows were superstimulated by treatment with progesterone, GnRH, FSH and prostaglandin F2α according to a standardized protocol. The resulting in vivo-matured oocytes were collected by OPU and used subsequently for the other experiments. The immature oocytes from cows in the non-stimulated group were collected by OPU and then subjected to maturation in vitro. We found that the rate of normally distributed cortical granules of the matured oocyte cytoplasm in the superstimulated group was significantly higher than that in the non-stimulated group. The normal cleavage rate (i.e., production of embryos with two equal blastomeres without fragmentation) and freezable blastocyst rate were significantly higher in the superstimulated group than in the non-stimulated group. Among the transferable blastocysts, the ratio of embryos from normal cleavage was also significantly higher in the superstimulated group than in the non-stimulated group. For in vivo-matured oocytes, it was observed that the pregnancy rates were significantly higher when normally cleaved embryos were used for transfer. Taken together, these results suggest that high-quality embryos with respect to developmental kinetics can be efficiently produced with the use of in vivo-matured oocytes collected by OPU from superstimulated Japanese Black cows.


Assuntos
Bovinos , Embrião de Mamíferos/citologia , Fertilização In Vitro/métodos , Técnicas de Maturação in Vitro de Oócitos , Recuperação de Oócitos , Oócitos/fisiologia , Indução da Ovulação , Animais , Transferência Embrionária/veterinária , Desenvolvimento Embrionário/fisiologia , Feminino , Fertilização In Vitro/veterinária , Técnicas de Maturação in Vitro de Oócitos/métodos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Masculino , Recuperação de Oócitos/veterinária , Oócitos/citologia , Oogênese/fisiologia , Indução da Ovulação/veterinária , Gravidez , Taxa de Gravidez , Resultado do Tratamento
17.
J Reprod Dev ; 65(2): 177-182, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-30745497

RESUMO

We examined the effect of the timing of removing cumulus cells surrounding porcine oocytes from small follicles (SFs, < 3 mm in diameter) and medium follicles (MFs; 3-6 mm in diameter) on the meiotic and developmental competence of the oocytes. Cumulus-oocyte complexes (COCs) were collected from SFs and MFs, and the oocytes were denuded at 0, 20, and 44 h after the start of in vitro maturation (IVM), and the meiotic progression of the oocytes was assessed at the end of the IVM period. The incidence of mature oocytes was significantly affected by both the origin of the COCs and the time when the oocytes were denuded. Although the percentage of mature oocytes was always higher when the COCs were collected from MFs than that when the COCs were collected from SFs, the maturation rate was significantly higher when the oocytes were denuded at 20 h than when they were denuded at 44 h after the start of IVM. When the mature oocytes were activated electrically, the developmental competence of the oocytes denuded at 20 and 44 h to reach the blastocyst stage did not differ, whereas the competence of the MF-derived oocytes was significantly higher than that of SF-derived oocytes. When the intracellular cAMP and cGMP levels in SF-derived oocytes were examined at 24 h of IVM, the levels of both were significantly decreased only in the oocytes denuded at 20 h. In conclusion, denuding oocytes at 20 h of IVM caused a significant reduction in ooplasmic cAMP and cGMP levels and increased the meiotic competence of the oocytes without any reduction in blastocyst formation, even in the case of SF-derived oocytes.


Assuntos
Separação Celular/métodos , Células do Cúmulo/citologia , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Técnicas de Maturação in Vitro de Oócitos/métodos , Meiose/efeitos dos fármacos , Oócitos/fisiologia , Animais , Separação Celular/veterinária , Células Cultivadas , Regulação para Baixo , Desenvolvimento Embrionário/fisiologia , Feminino , Técnicas de Maturação in Vitro de Oócitos/veterinária , Meiose/fisiologia , Oócitos/citologia , Oócitos/metabolismo , Suínos , Fatores de Tempo
18.
Dev Cell ; 48(5): 646-658.e6, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30713074

RESUMO

All living systems function out of equilibrium and exchange energy in the form of heat with their environment. Thus, heat flow can inform on the energetic costs of cellular processes, which are largely unknown. Here, we have repurposed an isothermal calorimeter to measure heat flow between developing zebrafish embryos and the surrounding medium. Heat flow increased over time with cell number. Unexpectedly, a prominent oscillatory component of the heat flow, with periods matching the synchronous early reductive cleavage divisions, persisted even when DNA synthesis and mitosis were blocked by inhibitors. Instead, the heat flow oscillations were driven by the phosphorylation and dephosphorylation reactions catalyzed by the cell-cycle oscillator, the biochemical network controlling mitotic entry and exit. We propose that the high energetic cost of cell-cycle signaling reflects the significant thermodynamic burden of imposing accurate and robust timing on cell proliferation during development.


Assuntos
Ciclo Celular/fisiologia , Proliferação de Células/fisiologia , Desenvolvimento Embrionário/fisiologia , Temperatura Alta , Animais , Proteína Quinase CDC2/metabolismo , Ciclinas/metabolismo , Replicação do DNA/fisiologia , Embrião não Mamífero/citologia , Mitose/fisiologia , Fosforilação , Peixe-Zebra/metabolismo
19.
PLoS Comput Biol ; 15(2): e1006579, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30716091

RESUMO

The reproducibility of embryonic development is remarkable, although molecular processes are intrinsically stochastic at the single-cell level. How the multicellular system resists the inevitable noise to acquire developmental reproducibility constitutes a fundamental question in developmental biology. Toward this end, we focused on vertebrate somitogenesis as a representative system, because somites are repeatedly reproduced within a single embryo whereas such reproducibility is lost in segmentation clock gene-deficient embryos. However, the effect of noise on developmental reproducibility has not been fully investigated, because of the technical difficulty in manipulating the noise intensity in experiments. In this study, we developed a computational model of ERK-mediated somitogenesis, in which bistable ERK activity is regulated by an FGF gradient, cell-cell communication, and the segmentation clock, subject to the intrinsic noise. The model simulation generated our previous in vivo observation that the ERK activity was distributed in a step-like gradient in the presomitic mesoderm, and its boundary was posteriorly shifted by the clock in a stepwise manner, leading to regular somite formation. Here, we showed that this somite regularity was robustly maintained against the noise. Removing the clock from the model predicted that the stepwise shift of the ERK activity occurs at irregular timing with irregular distance owing to the noise, resulting in somite size variation. This model prediction was recently confirmed by live imaging of ERK activity in zebrafish embryos. Through theoretical analysis, we presented a mechanism by which the clock reduces the inherent somite irregularity observed in clock-deficient embryos. Therefore, this study indicates a novel role of the segmentation clock in noise-resistant developmental reproducibility.


Assuntos
Padronização Corporal/fisiologia , Desenvolvimento Embrionário/fisiologia , Animais , Artefatos , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano , Biologia do Desenvolvimento/métodos , Embrião de Mamíferos , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Sistema de Sinalização das MAP Quinases , Mesoderma , Modelos Moleculares , Reprodutibilidade dos Testes , Somitos/fisiologia , Peixe-Zebra/embriologia
20.
Nat Commun ; 10(1): 496, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30700702

RESUMO

Spatially ordered embryo-like structures self-assembled from blastocyst-derived stem cells can be generated to mimic embryogenesis in vitro. However, the assembly system and developmental potential of such structures needs to be further studied. Here, we devise a nonadherent-suspension-shaking system to generate self-assembled embryo-like structures (ETX-embryoids) using mouse embryonic, trophoblast and extra-embryonic endoderm stem cells. When cultured together, the three cell types aggregate and sort into lineage-specific compartments. Signaling among these compartments results in molecular and morphogenic events that closely mimic those observed in wild-type embryos. These ETX-embryoids exhibit lumenogenesis, asymmetric patterns of gene expression for markers of mesoderm and primordial germ cell precursors, and formation of anterior visceral endoderm-like tissues. After transplantation into the pseudopregnant mouse uterus, ETX-embryoids efficiently initiate implantation and trigger the formation of decidual tissues. The ability of the three cell types to self-assemble into an embryo-like structure in vitro provides a powerful model system for studying embryogenesis.


Assuntos
Blastocisto/citologia , Embrião de Mamíferos/citologia , Células-Tronco/citologia , Animais , Implantação do Embrião , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/citologia , Camundongos
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