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1.
Nat Commun ; 11(1): 3491, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32661239

RESUMO

Sperm contributes genetic and epigenetic information to the embryo to efficiently support development. However, the mechanism underlying such developmental competence remains elusive. Here, we investigated whether all sperm cells have a common epigenetic configuration that primes transcriptional program for embryonic development. Using calibrated ChIP-seq, we show that remodelling of histones during spermiogenesis results in the retention of methylated histone H3 at the same genomic location in most sperm cell. This homogeneously methylated fraction of histone H3 in the sperm genome is maintained during early embryonic replication. Such methylated histone fraction resisting post-fertilisation reprogramming marks developmental genes whose expression is perturbed upon experimental reduction of histone methylation. A similar homogeneously methylated histone H3 fraction is detected in human sperm. Altogether, we uncover a conserved mechanism of paternal epigenetic information transmission to the embryo through the homogeneous retention of methylated histone in a sperm cells population.


Assuntos
Metilação de DNA/genética , Epigênese Genética/genética , Animais , Cromatina/genética , Cromatina/metabolismo , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Histonas/genética , Histonas/metabolismo , Masculino , Espermatogênese/genética , Espermatogênese/fisiologia , Xenopus
2.
Nat Commun ; 11(1): 3653, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32694534

RESUMO

The vasculature represents a highly plastic compartment, capable of switching from a quiescent to an active proliferative state during angiogenesis. Metabolic reprogramming in endothelial cells (ECs) thereby is crucial to cover the increasing cellular energy demand under growth conditions. Here we assess the impact of mitochondrial bioenergetics on neovascularisation, by deleting cox10 gene encoding an assembly factor of cytochrome c oxidase (COX) specifically in mouse ECs, providing a model for vasculature-restricted respiratory deficiency. We show that EC-specific cox10 ablation results in deficient vascular development causing embryonic lethality. In adult mice induction of EC-specific cox10 gene deletion produces no overt phenotype. However, the angiogenic capacity of COX-deficient ECs is severely compromised under energetically demanding conditions, as revealed by significantly delayed wound-healing and impaired tumour growth. We provide genetic evidence for a requirement of mitochondrial respiration in vascular endothelial cells for neoangiogenesis during development, tissue repair and cancer.


Assuntos
Mitocôndrias/metabolismo , Neoplasias/patologia , Neovascularização Patológica/patologia , Neovascularização Fisiológica , Cicatrização/fisiologia , Trifosfato de Adenosina/metabolismo , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Animais , Linhagem Celular Tumoral/transplante , Respiração Celular , Modelos Animais de Doenças , Embrião de Mamíferos , Desenvolvimento Embrionário/fisiologia , Células Endoteliais/fisiologia , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Feminino , Técnicas de Inativação de Genes , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Mitocôndrias/genética , Neoplasias/irrigação sanguínea , Fosforilação Oxidativa
3.
Nat Commun ; 11(1): 3760, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32724077

RESUMO

Human embryogenesis is hallmarked by two phases of yolk sac development. The primate hypoblast gives rise to a transient primary yolk sac, which is rapidly superseded by a secondary yolk sac during gastrulation. Moreover, primate embryos form extraembryonic mesoderm prior to gastrulation, in contrast to mouse. The function of the primary yolk sac and the origin of extraembryonic mesoderm remain unclear. Here, we hypothesise that the hypoblast-derived primary yolk sac serves as a source for early extraembryonic mesoderm, which is supplemented with mesoderm from the gastrulating embryo. We discuss the intricate relationship between the yolk sac and the primate embryo and highlight the pivotal role of the yolk sac as a multifunctional hub for haematopoiesis, germ cell development and nutritional supply.


Assuntos
Desenvolvimento Embrionário/fisiologia , Mesoderma/embriologia , Primatas/embriologia , Saco Vitelino/embriologia , Animais , Diferenciação Celular/fisiologia , Células Germinativas Embrionárias/fisiologia , Hematopoese/fisiologia
4.
Nat Commun ; 11(1): 2958, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32528010

RESUMO

The high incidence of aneuploidy in the embryo is considered the principal cause for low human fecundity. However, the prevalence of aneuploidy dramatically declines as pregnancy progresses, with the steepest drop occurring as the embryo completes implantation. Despite the fact that the plasticity of the embryo in dealing with aneuploidy is fundamental to normal development, the mechanisms responsible for eliminating aneuploid cells are unclear. Here, using a mouse model of chromosome mosaicism, we show that aneuploid cells are preferentially eliminated from the embryonic lineage in a p53-dependent process involving both autophagy and apoptosis before, during and after implantation. Moreover, we show that diploid cells in mosaic embryos undertake compensatory proliferation during the implantation stages to confer embryonic viability. Together, our results indicate a close link between aneuploidy, autophagy, and apoptosis to refine the embryonic cell population and ensure only chromosomally fit cells proceed through development of the fetus.


Assuntos
Aneuploidia , Apoptose/fisiologia , Autofagia/fisiologia , Animais , Apoptose/genética , Autofagia/genética , Proliferação de Células/genética , Proliferação de Células/fisiologia , Diploide , Implantação do Embrião , Embrião de Mamíferos/metabolismo , Embriologia , Desenvolvimento Embrionário/fisiologia , Feminino , Imunofluorescência , Camadas Germinativas/metabolismo , Camundongos , Mosaicismo
5.
PLoS One ; 15(6): e0235140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32574203

RESUMO

BACKGROUND: Due to improved treatment, there is an increasing focus on the reproductive potential of survivors of childhood cancer. Cytotoxic chemotherapy accelerates the decline in the number of primordial follicles within the mammalian ovary at all ages, but effects on the developmental potential of remaining oocytes following prepubertal cancer treatment are unclear. OBJECTIVES: To investigate whether cyclophosphamide (CY) exposure in the prepubertal period in female mice influences ovarian function and the functional competence of oocytes in adulthood. METHODS: This study used Swiss albino mice as the experimental model. Female mice were treated with 200 mg/kg CY on either postnatal day 14 (CY14), 21 (CY21) or 28 (CY28) i.e at a prepubertal and 2 young postpubertal ages. At 14 weeks of life, ovarian function, functional competence of oocytes, and embryo quality were assessed. RESULTS: The number of primordial follicles decreased significantly in CY14 and CY21 groups compared to control (p < 0.01). The number of oocytes from superovulated was 8.5 ± 1.4, 24.1 ± 2.9 and 26.8 ± 2.1 in CY14, CY21 and CY28 respectively which was significantly lower than control (50.2 ± 3.2; p < 0.001). In vitro culture of CY14 embryos demonstrated only 55.4% blastocyst formation (p < 0.0001) and reduced ability of inner cell mass (ICM) to proliferate in vitro (p < 0.05) at 120 and 216 h post insemination respectively. On the other hand, ICM proliferation was unaltered in 2 young postpubertal ages. CONCLUSION: Our results indicate long-term effects on the developmental competence of oocytes exposed to CY in early but not adult life. These data provide a mechanism whereby long-term fertility can be impaired after chemotherapy exposure, despite the continuing presence of follicles within the ovary, and support the need for fertility preservation in prepubertal girls before alkylating agent exposure.


Assuntos
Blastocisto/efeitos dos fármacos , Ciclofosfamida/farmacologia , Desenvolvimento Embrionário/efeitos dos fármacos , Reserva Ovariana/efeitos dos fármacos , Maturidade Sexual/fisiologia , Animais , Hormônio Antimülleriano/sangue , Antineoplásicos Alquilantes/farmacologia , Blastocisto/citologia , Blastocisto/fisiologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Proliferação de Células/efeitos dos fármacos , Ciclofosfamida/administração & dosagem , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/embriologia , Desenvolvimento Embrionário/fisiologia , Feminino , Fertilidade/efeitos dos fármacos , Fertilidade/fisiologia , Camundongos , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Tamanho do Órgão/efeitos dos fármacos , Reserva Ovariana/fisiologia , Ovário/anatomia & histologia , Ovário/citologia , Ovário/efeitos dos fármacos , Fatores de Tempo
6.
Proc Natl Acad Sci U S A ; 117(26): 14636-14641, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32541064

RESUMO

Understanding the coordination of cell-division timing is one of the outstanding questions in the field of developmental biology. One active control parameter of the cell-cycle duration is temperature, as it can accelerate or decelerate the rate of biochemical reactions. However, controlled experiments at the cellular scale are challenging, due to the limited availability of biocompatible temperature sensors, as well as the lack of practical methods to systematically control local temperatures and cellular dynamics. Here, we demonstrate a method to probe and control the cell-division timing in Caenorhabditis elegans embryos using a combination of local laser heating and nanoscale thermometry. Local infrared laser illumination produces a temperature gradient across the embryo, which is precisely measured by in vivo nanoscale thermometry using quantum defects in nanodiamonds. These techniques enable selective, controlled acceleration of the cell divisions, even enabling an inversion of division order at the two-cell stage. Our data suggest that the cell-cycle timing asynchrony of the early embryonic development in C. elegans is determined independently by individual cells rather than via cell-to-cell communication. Our method can be used to control the development of multicellular organisms and to provide insights into the regulation of cell-division timings as a consequence of local perturbations.


Assuntos
Temperatura Corporal/fisiologia , Divisão Celular/fisiologia , Desenvolvimento Embrionário/fisiologia , Pontos Quânticos/química , Termometria , Animais , Caenorhabditis elegans/embriologia , Nanodiamantes/química , Termometria/instrumentação , Termometria/métodos
7.
Anim Sci J ; 91(1): e13374, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378282

RESUMO

Superovulation is an important animal breeding biotechnology, while the quality of embryos obtained from superovulation is unstable in cattle. The relationship between the microorganisms in the cattle uterus and embryo qualities was determined to identify the key bacterial populations affecting early embryonic development. A total of 10 Xia Nan cows underwent superovulation, we collected cervical mucus and flush samples to investigated by 16S rDNA sequencing. Results showed that there were abundant microorganisms in cervical mucus, but no obvious relationship with the quality of embryos. The clustering results of flush samples were consistent with the grouping of embryo quality. Proteobacteria accounted for more than 95% of the total bacterial community in group A with the best embryo quality (qualified embryo ratio above 0.8), and as embryo quality decreased, the Proteobacteria proportion also decreased. In contrast to the proportion of Proteobacteria, the proportions of Firmicutes and Bacteroidetes significantly increased as embryo quality decreased. For group C with the worst embryo quality, the proportions of Firmicutes and Bacteroidetes increased to 4.7 times and 12.3 times of group A, respectively. These results showed that the quantities and proportions of Firmicutes and Bacteroidetes may be related to early embryonic development in cattle.


Assuntos
Bovinos/fisiologia , Embrião de Mamíferos , Desenvolvimento Embrionário/fisiologia , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Superovulação , Útero/microbiologia , Animais , Endométrio/microbiologia , Feminino , Firmicutes/genética , Firmicutes/isolamento & purificação , Firmicutes/fisiologia , Gravidez , Proteobactérias/fisiologia , Análise de Sequência de DNA
8.
Nat Commun ; 11(1): 2366, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398639

RESUMO

Epithelial bending is a fundamental process that shapes organs during development. Previously known mechanisms involve cells locally changing shape from columnar to wedge-shaped. Here we report a different mechanism that occurs without cell wedging. In mammalian salivary glands and teeth, we show that initial invagination occurs through coordinated vertical cell movement: cells towards the periphery of the placode move vertically upwards while their more central neighbours move downwards. Movement is achieved by active cell-on-cell migration: outer cells migrate with apical, centripetally polarised leading edge protrusions but remain attached to the basal lamina, depressing more central neighbours to "telescope" the epithelium downwards into underlying mesenchyme. Inhibiting protrusion formation by Arp2/3 protein blocks invagination. FGF and Hedgehog morphogen signals are required, with FGF providing a directional cue. These findings show that epithelial bending can be achieved by a morphogenetic mechanism of coordinated cell rearrangement quite distinct from previously recognised invagination processes.


Assuntos
Movimento Celular/fisiologia , Desenvolvimento Embrionário/fisiologia , Epitélio/embriologia , Dente Molar/embriologia , Glândulas Salivares/embriologia , Animais , Ectoderma/citologia , Ectoderma/embriologia , Embrião de Mamíferos/citologia , Células Epiteliais/fisiologia , Feminino , Microscopia Intravital , Masculino , Camundongos , Dente Molar/citologia , Glândulas Salivares/citologia , Técnicas de Cultura de Tecidos
9.
Nat Commun ; 11(1): 2383, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32409662

RESUMO

The duration of the developmental period represents a fundamental axis of life-history variation, yet broad insights regarding the drivers of this diversity are currently lacking. Here, we test mechanistic and ecological explanations for the evolution of developmental duration using embryological data and information on incubation and fledging for 3096 avian species. Developmental phases associated primarily with growth are the longest and most variable, consistent with a role for allometric constraint in determining the duration of development. In addition, developmental durations retain a strong imprint of deep evolutionary history and body size differences among species explain less variation than previously thought. Finally, we reveal ecological correlates of developmental durations, including variables associated with the relative safety of the developmental environment and pressures of breeding phenology. Overall, our results provide broad-scale insight into the relative importance of mechanistic, ecological and evolutionary constraints in shaping the diversification of this key life-history trait.


Assuntos
Aves/fisiologia , Desenvolvimento Embrionário/fisiologia , Traços de História de Vida , Modelos Biológicos , Animais , Tamanho Corporal/fisiologia , Conjuntos de Dados como Assunto , Ecologia/métodos , Embrião não Mamífero , Feminino , Masculino , Comportamento de Nidação/fisiologia , Fatores de Tempo
10.
Sci China Life Sci ; 63(6): 849-865, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32291558

RESUMO

The number of growth factors involved in female fertility has been extensively studied, but reluctance to add essential growth factors in culture media has limited progress in optimizing embryonic growth and implantation outcomes, a situation that has ultimately led to reduced pregnancy outcomes. Insulin-like growth factor II (IGF-II) is the most intricately regulated of all known reproduction-related growth factors characterized to date, and is perhaps the predominant growth factor in human ovarian follicles. This review aims to concisely summarize what is known about the role of IGF-II in follicular development, oocyte maturation, embryonic development, implantation success, placentation, fetal growth, and in reducing placental cell apoptosis, as well as present strategies that use growth factors in culture systems to improve the developmental potential of oocytes and embryos in different species. Synthesizing the present knowledge about the physiological roles of IGF-II in follicular development, oocyte maturation, and early embryonic development should, on the one hand, deepen our overall understanding of the potential beneficial effects of growth factors in female reproduction and on the other hand support development (optimization) of improved outcomes for assisted reproductive technologies.


Assuntos
Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/fisiologia , Reprodução/fisiologia , Animais , Desenvolvimento Embrionário/fisiologia , Feminino , Desenvolvimento Fetal/fisiologia , Regulação da Expressão Gênica , Humanos , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Gravidez
11.
Nature ; 580(7801): 124-129, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32238941

RESUMO

Pluripotent stem cells are increasingly used to model different aspects of embryogenesis and organ formation1. Despite recent advances in in vitro induction of major mesodermal lineages and cell types2,3, experimental model systems that can recapitulate more complex features of human mesoderm development and patterning are largely missing. Here we used induced pluripotent stem cells for the stepwise in vitro induction of presomitic mesoderm and its derivatives to model distinct aspects of human somitogenesis. We focused initially on modelling the human segmentation clock, a major biological concept believed to underlie the rhythmic and controlled emergence of somites, which give rise to the segmental pattern of the vertebrate axial skeleton. We observed oscillatory expression of core segmentation clock genes, including HES7 and DKK1, determined the period of the human segmentation clock to be around five hours, and demonstrated the presence of dynamic travelling-wave-like gene expression in in vitro-induced human presomitic mesoderm. Furthermore, we identified and compared oscillatory genes in human and mouse presomitic mesoderm derived from pluripotent stem cells, which revealed species-specific and shared molecular components and pathways associated with the putative mouse and human segmentation clocks. Using CRISPR-Cas9-based genome editing technology, we then targeted genes for which mutations in patients with segmentation defects of the vertebrae, such as spondylocostal dysostosis, have been reported (HES7, LFNG, DLL3 and MESP2). Subsequent analysis of patient-like and patient-derived induced pluripotent stem cells revealed gene-specific alterations in oscillation, synchronization or differentiation properties. Our findings provide insights into the human segmentation clock as well as diseases associated with human axial skeletogenesis.


Assuntos
Relógios Biológicos/fisiologia , Desenvolvimento Embrionário/fisiologia , Células-Tronco Pluripotentes/citologia , Somitos/citologia , Somitos/crescimento & desenvolvimento , Anormalidades Múltiplas/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Relógios Biológicos/genética , Desenvolvimento Embrionário/genética , Edição de Genes , Regulação da Expressão Gênica no Desenvolvimento/genética , Glicosiltransferases/deficiência , Glicosiltransferases/genética , Hérnia Diafragmática/genética , Humanos , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Fenótipo , Somitos/metabolismo , Fatores de Tempo
12.
PLoS One ; 15(4): e0230943, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240230

RESUMO

Pericellular and extracellular proteoglycans play an important role in modulating morphogen gradients and signal transductions. Chondroitin sulfate proteoglycan 4 (Cspg4) is a membrane spanning proteoglycan expressed in immature progenitor cells and cancer cells. Cspg4 participates in cellular events such as proliferation, migration and signal transduction, and these events are generally important for embryo development. In this study, we characterized Cspg4 for its roles in zebrafish embryonic development. Our results demonstrated that cspg4 was maternally expressed from 0 to 3 hours post fertilization (hpf) and expressed in the anterior and posterior embryo end after 9 hpf. Knocking-down cspg4 resulted in a shorter anterior-posterior axis than control embryo, which could be rescued by co-injecting wnt11 mRNA suggesting that Cspg4 regulates body axis organization through modulating the Wnt/planar cell polarity signaling pathway. In addition, overexpressing cspg4 caused cyclopia. The Cspg4 transmembrane domain mutant embryo phenocopied the global over-expression of cspg4 mRNA and led to cyclopia with a very low penetrance. Our results demonstrated that the quantitatively and spatially accurate distribution of Cspg4 is critical for body axis and midline development during gastrulation.


Assuntos
Antígenos/metabolismo , Polaridade Celular/fisiologia , Proteoglicanas/metabolismo , Via de Sinalização Wnt/fisiologia , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/fisiologia , RNA Mensageiro/metabolismo
13.
Integr Zool ; 15(4): 338-348, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32297704

RESUMO

Low-elevation species can migrate toward higher elevations to survive in a warming world. However, animals' responses to hypoxia when migrating to high elevations have rarely been addressed. To identify the response of low-elevation lizards to high-elevation hypoxia, we collected field body temperatures (Tfb ) and operative temperatures (Te ) of lizards (Eremias argus) from a low-elevation population (1036 m) and a high-elevation population (2036 m), and then determined adult thermal physiology, embryonic development, and hatchling phenotypes after acclimating low-elevation lizards and incubating their eggs in conditions mimicking the low-elevation oxygen condition (18.5% O2 ) and high-elevation oxygen (hypoxic) condition (16.5% O2 ). Our study revealed that Tfb and Te were higher for the low-elevation population compared to the high-elevation population. We also found adults from low elevation acclimated to hypoxia preferred lower body temperatures, but did not show changes in locomotor performance or growth. In addition, hypoxia did not affect embryonic development (hatching time and success) or hatchling phenotypes (body size and locomotor performance). These results suggest that adult lizards from low elevations can respond to hypoxia-induced stress when migrating to high elevations by behaviorally thermoregulating to lower body temperatures in order to sustain normal functions. Similarly, low-elevation embryos can develop normally (with unchanged hatching success and offspring phenotypes) under the high-elevation hypoxic condition. This study highlights that low-elevation populations of a species that inhabits a range of elevations can buffer the impact of high-elevation hypoxic conditions to some degree and thus attain similar fitness to the source population.


Assuntos
Regulação da Temperatura Corporal , Desenvolvimento Embrionário/fisiologia , Lagartos/fisiologia , Oxigênio/metabolismo , Fenótipo , Aclimatação , Altitude , Anaerobiose , Animais , China , Embrião não Mamífero/fisiologia , Feminino , Lagartos/crescimento & desenvolvimento , Masculino
14.
Front Biosci (Schol Ed) ; 12: 116-136, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32114451

RESUMO

Oocyte quality influences early embryonic survival, establishment and maintenance of pregnancy, fetal development and adult diseases. The developmental competence of oocytes is acquired gradually and increases with follicular development. The ability of an oocyte to develop into an embryo depends on, having enough specific information in the form of mRNA or proteins. If this information is insufficient, defects in nuclear or cytoplasmic maturation, or in both processes, may arise and thus affect the in vitro development of fertilized oocytes. The greater developmental competence of oocytes aspirated from larger follicles is reported as compared with smaller follicles. Oocyte developmental competence is greatly correlated with the morphology of the cumulus oocyte complexes (COCs). Apart from morphological or biochemical markers, molecular markers have also been investigated. Until now, no specific markers of oocyte developmental competence could be described for the oocyte developmental competence. To, utilize female germplasm to its maximum, there is a need to enhance developmental competence of lesser competent oocytes derived from the follicles which are not fully grown. The oocyte pre-maturation and maturation conditions affect gene expression not only in the oocyte but till the blastocyst stages too. Strategies have been discussed in this review would be useful to enhance the developmental competence of oocytes.


Assuntos
Oócitos/fisiologia , Animais , Blastocisto/citologia , Blastocisto/fisiologia , Células do Cúmulo/citologia , Células do Cúmulo/fisiologia , Desenvolvimento Embrionário/fisiologia , Feminino , Humanos , Oócitos/citologia , Oócitos/crescimento & desenvolvimento , Oogênese/fisiologia , Gravidez
15.
Nat Commun ; 11(1): 1269, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152267

RESUMO

Multicellular rosettes are transient epithelial structures that serve as intermediates during diverse organ formation. We have identified a unique contributor to rosette formation in zebrafish Kupffer's vesicle (KV) that requires cell division, specifically the final stage of mitosis termed abscission. KV utilizes a rosette as a prerequisite before forming a lumen surrounded by ciliated epithelial cells. Our studies identify that KV-destined cells remain interconnected by cytokinetic bridges that position at the rosette's center. These bridges act as a landmark for directed Rab11 vesicle motility to deliver an essential cargo for lumen formation, CFTR (cystic fibrosis transmembrane conductance regulator). Here we report that premature bridge cleavage through laser ablation or inhibiting abscission using optogenetic clustering of Rab11 result in disrupted lumen formation. We present a model in which KV mitotic cells strategically place their cytokinetic bridges at the rosette center, where Rab11-associated vesicles transport CFTR to aid in lumen establishment.


Assuntos
Divisão Celular/fisiologia , Polaridade Celular/fisiologia , Embrião não Mamífero/fisiologia , Desenvolvimento Embrionário/fisiologia , Macrófagos do Fígado/fisiologia , Organogênese/fisiologia , Peixe-Zebra/embriologia , Animais , Linhagem Celular , Movimento Celular , Cílios/fisiologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/genética , Células Epiteliais/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Macrófagos do Fígado/citologia , Mitose , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
16.
Aquat Toxicol ; 222: 105466, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32172180

RESUMO

The co-occurrence of hypoxia and xenobiotics is extremely common in natural environments, highlighting the necessity to elicit their interaction on aquatic toxicities. In the present study, marine medaka embryos were exposed to various concentrations (nominal 0, 1, 3.3 and 10 mg/L) of perfluorobutane sulfonate (PFBS), an environmental pollutant of emerging concern, under either normoxia (6.9 mg/L) or hypoxia (1.7 mg/L) condition. After acute exposure till 15 days post-fertilization, single or combined toxicities of PFBS and hypoxia on embryonic development (e.g., mortality, hatching and heartbeat) and endocrine systems were investigated. Sex and thyroid hormones were measured by enzyme-linked immunosorbent assay. Transcriptional changes of endocrine genes were determined by quantitative real-time PCR assays. Co-exposure to 10 mg/L PFBS and hypoxia caused a further reduction in survival rate and heart beat compared to single exposure. PFBS induced a precocious hatching, while no larvae hatched under hypoxia condition. By disturbing the balance of sex hormones, either PFBS or hypoxia single exposure produced an anti-estrogenic activity in medaka larvae. However, PFBS and hypoxia combinations reversed to estrogenic activity in co-exposed larvae. Variation in disrupting pattern may be attributed to the interactive effects on steroidogenic pathway involving diverse cytochrome P450 enzymes. Regarding thyroid system, PFBS exposure caused detriments of multiple processes along thyroidal axis (e.g., feedback regulation, synthesis and transport of thyroid hormones, receptor-mediated signaling and thyroid gland development), while hypoxia potently impaired the development and function of thyroid gland. Combinations of PFBS and hypoxia interacted to dysregulate the function of thyroid endocrine system. In summary, the present study revealed the dynamic interaction of PFBS pollutant and hypoxia on aquatic developmental toxicities and endocrine disruption. Considering the frequent co-occurrence of xenobiotics and hypoxia, current results would be beneficial to improve our understanding about their interactive mechanisms and provide baseline evidences for accurate ecological risk evaluation.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Fluorcarbonetos/toxicidade , Hipóxia/metabolismo , Oryzias/metabolismo , Ácidos Sulfônicos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/fisiologia , Feminino , Hormônios Esteroides Gonadais/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Masculino , Oryzias/crescimento & desenvolvimento , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/embriologia , Glândula Tireoide/metabolismo , Hormônios Tireóideos/metabolismo
17.
Nat Commun ; 11(1): 1366, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170064

RESUMO

In Arabidopsis, a zygote undergoes asymmetrical cell division that establishes the first two distinct cell types of early proembryos, apical and basal cells. However, the genome-wide transcriptional activities that guide divergence of apical and basal cell development remain unknown. Here, we present a comprehensive transcriptome analysis of apical and basal cell lineages, uncovering distinct molecular pathways during cell lineage specification. Selective deletion of inherited transcripts and specific de novo transcription contribute to the establishment of cell lineage-specific pathways for cell fate specification. Embryo-related pathways have been specifically activated in apical cell lineage since 1-cell embryo stage, but quick transcriptome remodeling toward suspensor-specific pathways are found in basal cell lineage. Furthermore, long noncoding RNAs and alternative splicing isoforms may be involved in cell lineage specification. This work also provides a valuable lineage-specific transcriptome resource to elucidate the molecular pathways for divergence of apical and basal cell lineages at genome-wide scale.


Assuntos
Linhagem da Célula , Perfilação da Expressão Gênica , Desenvolvimento Vegetal/fisiologia , Sementes/fisiologia , Arabidopsis , Linhagem da Célula/genética , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Desenvolvimento Vegetal/genética , RNA Longo não Codificante , RNA não Traduzido , Sementes/citologia , Sementes/genética , Fatores de Transcrição , Transcriptoma , Zigoto/metabolismo
18.
Nat Commun ; 11(1): 1357, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170114

RESUMO

Embryonic Stem Cell (ESC) differentiation requires complex cell signalling network dynamics, although the key molecular events remain poorly understood. Here, we use phosphoproteomics to identify an FGF4-mediated phosphorylation switch centred upon the key Ephrin receptor EPHA2 in differentiating ESCs. We show that EPHA2 maintains pluripotency and restrains commitment by antagonising ERK1/2 signalling. Upon ESC differentiation, FGF4 utilises a bimodal strategy to disable EPHA2, which is accompanied by transcriptional induction of EFN ligands. Mechanistically, FGF4-ERK1/2-RSK signalling inhibits EPHA2 via Ser/Thr phosphorylation, whilst FGF4-ERK1/2 disrupts a core pluripotency transcriptional circuit required for Epha2 gene expression. This system also operates in mouse and human embryos, where EPHA receptors are enriched in pluripotent cells whilst surrounding lineage-specified trophectoderm expresses EFNA ligands. Our data provide insight into function and regulation of EPH-EFN signalling in ESCs, and suggest that segregated EPH-EFN expression coordinates cell fate with compartmentalisation during early embryonic development.


Assuntos
Diferenciação Celular/fisiologia , Embrião de Mamíferos/metabolismo , Células-Tronco Embrionárias/metabolismo , Proteômica/métodos , Receptor EphA2/metabolismo , Animais , Diferenciação Celular/genética , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Efrina-A2 , Fator 4 de Crescimento de Fibroblastos/metabolismo , Humanos , Ligantes , Sistema de Sinalização das MAP Quinases , Camundongos , Fosforilação , Receptor EphA2/genética , Transdução de Sinais
19.
Proc Natl Acad Sci U S A ; 117(13): 7236-7244, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32184326

RESUMO

Spatial cellular organization is fundamental for embryogenesis. Remarkably, coculturing embryonic stem cells (ESCs) and trophoblast stem cells (TSCs) recapitulates this process, forming embryo-like structures. However, mechanisms driving ESC-TSC interaction remain elusive. We describe specialized ESC-generated cytonemes that react to TSC-secreted Wnts. Cytoneme formation and length are controlled by actin, intracellular calcium stores, and components of the Wnt pathway. ESC cytonemes select self-renewal-promoting Wnts via crosstalk between Wnt receptors, activation of ionotropic glutamate receptors (iGluRs), and localized calcium transients. This crosstalk orchestrates Wnt signaling, ESC polarization, ESC-TSC pairing, and consequently synthetic embryogenesis. Our results uncover ESC-TSC contact-mediated signaling, reminiscent of the glutamatergic neuronal synapse, inducing spatial self-organization and embryonic cell specification.


Assuntos
Comunicação Celular/fisiologia , Células-Tronco Embrionárias/metabolismo , Pseudópodes/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Drosophila , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/fisiologia , Camundongos , Trofoblastos/metabolismo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/fisiologia
20.
Animal ; 14(S1): s103-s112, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32024564

RESUMO

Assisted reproduction techniques (ARTs) provide access to early stage embryos whose analysis and assessment deliver valuable information. The handling of embryos, including the in vitro production of bovine embryos, is a rapidly evolving area which nonetheless exposes the embryos to unnatural conditions for a period of time. The Fallopian tube provides innumerable quantitative and qualitative factors, all of which guarantee the successful development of the embryo. It is well known that the Fallopian tube can be bypassed, using embryo transfer, resulting in successful implantation in the target recipient animal and the birth of calves. However, the question arises as to whether such circumvention has a negative impact on the embryo during this sensitive development period. First crosstalk between the embryo and its environment confirms mutual recognition activities and indicate bilateral effects. Nowadays, in vitro production of bovine embryos is a well-established technology. However, it is still evident that in vitro generated embryos are not qualitatively comparable to embryos obtained ex vivo. To counteract these differences, comparative studies between in vitro and ex vivo embryos are advantageous, as embryos grown in their physiological environment can provide a blueprint or gold standard against which to compare embryos produced in vitro. Attempts to harness the bovine oviduct were sometimes very invasive and did not result in wide acceptance and routine use. Long-term development and refinement of transvaginal endoscopy for accessing the bovine oviduct has meanwhile been routinely applied for research as well as in practice. Comparative studies combining in vitro development with development in the cattle oviduct revealed that the environmental conditions to which the embryo is exposed before activation of the embryonic genome can have detrimental and lasting effects on its further development. These effects are manifested as deviations in gene expression profiles and methylation signatures as well as frequency of whole chromosomal or segmental aberrations. Furthermore, it was shown that hormonal superstimulation (multiple ovulation and embryo transfer), varying progesterone concentrations as well as metabolic disorders caused by high milk production, markedly affected embryo development in the postpartum period. Assisted reproductive techniques that allow the production and handling of extra numbers of generated embryos promise to have a very high impact on scientific and practical application. Any influence on the early embryonic life, both in animals and in vitro, is accompanied by a sensitive change in embryonic activity and should be assessed in vivo on the basis of physiological conditions before being used for ART.


Assuntos
Bovinos/fisiologia , Desenvolvimento Embrionário/fisiologia , Meio Ambiente , Reprodução , Animais , Bovinos/embriologia , Implantação do Embrião , Transferência Embrionária/veterinária , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/fisiologia , Tubas Uterinas/embriologia , Tubas Uterinas/fisiologia , Feminino , Oviductos/embriologia , Oviductos/fisiologia , Gravidez , Progesterona/metabolismo
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