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Decidualisation of the endometrium is a key event in early pregnancy, which enables embryo implantation. Importantly, the molecular processes impairing decidualisation in obese mothers are yet to be characterised. We hypothesise that impaired decidualisation in obese mice is mediated by the upregulation of leptin modulators, the suppressor of cytokine signalling 3 (SOCS3) and the protein tyrosine phosphatase non-receptor type 2 (PTPN2), together with the disruption of progesterone (P4)-signal transducer and activator of transcription (STAT3) signalling. After feeding mice with chow diet (CD) or high-fat diet (HFD) for 16 weeks, we confirmed the downregulation of P4 and oestradiol (E2) steroid receptors in decidua from embryonic day (E) 6.5 and decreased proliferation of stromal cells from HFD. In vitro decidualised mouse endometrial stromal cells (MESCs) and E6.5 deciduas from the HFD showed decreased expression of decidualisation markers, followed by the upregulation of SOCS3 and PTPN2 and decreased phosphorylation of STAT3. In vivo and in vitro leptin treatment of mice and MESCs mimicked the results observed in the obese model. The downregulation of Socs3 and Ptpn2 after siRNA transfection of MESCs from HFD mice restored the expression level of decidualisation markers. Finally, DIO mice placentas from E18.5 showed decreased labyrinth development and vascularisation and fetal growth restricted embryos. The present study revealed major defects in decidualisation in obese mice, characterised by altered uterine response to E2 and P4 steroid signalling. Importantly, altered hormonal response was associated with increased expression of leptin signalling modulators SOCS3 and PTPN2. Elevated levels of SOCS3 and PTPN2 were shown to molecularly affect decidualisation in obese mice, potentially disrupting the STAT3-PR regulatory molecular hub.
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Decidua , Retardo del Crecimiento Fetal , Leptina , Placenta , Transducción de Señal , Animales , Femenino , Ratones , Embarazo , Decidua/metabolismo , Decidua/patología , Dieta Alta en Grasa/efectos adversos , Retardo del Crecimiento Fetal/metabolismo , Retardo del Crecimiento Fetal/patología , Leptina/metabolismo , Ratones Endogámicos C57BL , Ratones Obesos , Obesidad/metabolismo , Obesidad/patología , Placenta/metabolismo , Progesterona/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 2/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 2/genética , Factor de Transcripción STAT3/metabolismo , Células del Estroma/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/genéticaRESUMEN
The glycosylphosphatidylinositol (GPI) biosynthetic pathway in the endoplasmic reticulum (ER) is crucial for generating GPI-anchored proteins (GPI-APs), which are translocated to the cell surface and play a vital role in cell signaling and adhesion. This study focuses on two integral components of the GPI pathway, the PIGL and PIGF proteins, and their significance in trophoblast biology. We show that GPI pathway mutations impact on placental development impairing the differentiation of the syncytiotrophoblast (SynT), and especially the SynT-II layer, which is essential for the establishment of the definitive nutrient exchange area within the placental labyrinth. CRISPR/Cas9 knockout of Pigl and Pigf in mouse trophoblast stem cells (mTSCs) confirms the role of these GPI enzymes in syncytiotrophoblast differentiation. Mechanistically, impaired GPI-AP generation induces an excessive unfolded protein response (UPR) in the ER in mTSCs growing in stem cell conditions, akin to what is observed in human preeclampsia. Upon differentiation, the impairment of the GPI pathway hinders the induction of WNT signaling for early SynT-II development. Remarkably, the transcriptomic profile of Pigl- and Pigf-deficient cells separates human patient placental samples into preeclampsia and control groups, suggesting an involvement of Pigl and Pigf in establishing a preeclamptic gene signature. Our study unveils the pivotal role of GPI biosynthesis in early placentation and uncovers a new preeclampsia gene expression profile associated with mutations in the GPI biosynthesis pathway, providing novel molecular insights into placental development with implications for enhanced patient stratification and timely interventions.
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Diferenciación Celular , Glicosilfosfatidilinositoles , Placentación , Trofoblastos , Trofoblastos/metabolismo , Trofoblastos/citología , Femenino , Embarazo , Animales , Humanos , Ratones , Placentación/genética , Glicosilfosfatidilinositoles/metabolismo , Glicosilfosfatidilinositoles/biosíntesis , Placenta/metabolismo , Placenta/citología , Vía de Señalización Wnt , Preeclampsia/metabolismo , Preeclampsia/genética , Preeclampsia/patología , Retículo Endoplásmico/metabolismo , Vías Biosintéticas/genética , Respuesta de Proteína Desplegada , Sistemas CRISPR-CasRESUMEN
The placenta is the organ that dictates the reproductive outcome of mammalian pregnancy by supplying nutrients and oxygen to the developing fetus to sustain its normal growth. During early mammalian development, trophoblast cells are the earliest cell type to differentiate with multipotent capacity to generate the trophoblast components of the placenta. The isolation and use of mouse trophoblast stem cells (mTSCs) to model in vitro trophoblast differentiation, in combination with CRISPR/Cas9 genome editing technology, has provided tremendous insight into the molecular mechanisms governing early mouse placentation. By knocking out a specific gene of interest in mTSCs, researchers are shedding light onto the molecular pathways involved in normal placental development and pregnancy disorders associated with abnormal placentation. In this chapter, we provide a detailed protocol for the genetic modification of mTSCs by using CRISPR/Cas9 genome editing system.
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Sistemas CRISPR-Cas , Placenta , Embarazo , Femenino , Animales , Ratones , Ratones Noqueados , Trofoblastos , Diferenciación Celular/genética , Células Madre , MamíferosRESUMEN
The placenta is a vital organ that regulates nutrient supply to the developing embryo during gestation. In mice, the placenta is composed of trophoblast lineage and mesodermal derivatives, which merge through the chorioallantoic fusion process in a critical event for the progression of placenta development. The trophoblast lineage is derived from self-renewing, multipotent cells known as mouse trophoblast stem cells (mTSCs). These cells are a valuable tool that allows scientists to comprehend the signals regulating major placental cell types' self-renewal and differentiation capacity. Recent advances in CRISPR-Cas9 genome editing applied in mTSCs have provided novel insights into the molecular networks involved in placentation. Here, we present a comprehensive CRISPR activation (CRISPRa) protocol based on the CRISPR/gRNA-directed synergistic activation mediator (SAM) method to overexpress specific target genes in mTSCs.
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Placenta , ARN Guía de Sistemas CRISPR-Cas , Embarazo , Femenino , Animales , Ratones , Trofoblastos , Placentación/fisiología , Diferenciación Celular/genética , Células MadreRESUMEN
Global polystyrene (PS) production has been influenced by the lightness and heat resistance this material offers in different applications, such as construction and packaging. However, population growth and the lack of PS recycling lead to a large waste generation, affecting the environment. Pyrolysis has been recognized as an effective recycling method, converting PS waste into valuable products in the chemical industry. The present work addresses a systematic, bibliometric, and statistical analysis of results carried out from 2015 to 2022, making an extensive critique of the most influential operation parameters in the thermo-catalytic pyrolysis of PS and its waste. The systematic study showed that the conversion of PS into a liquid with high aromatic content (84.75% of styrene) can be achieved by pyrolysis. Discussion of PS as fuel is described compared to commercial fuels. In addition, PS favors the production of liquid fuel when subjected to co-pyrolysis with biomass, improving its properties such as viscosity and energy content. A statistical analysis of the data compilation was also discussed, evaluating the influence of temperature, reactor design, and catalysts on product yield.
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DNA methylation is a repressive epigenetic modification that is essential for development, exemplified by the embryonic and perinatal lethality observed in mice lacking de novo DNA methyltransferases (DNMTs). Here we characterise the role for DNMT3A, 3B and 3L in gene regulation and development of the mouse placenta. We find that each DNMT establishes unique aspects of the placental methylome through targeting to distinct chromatin features. Loss of Dnmt3b results in de-repression of germline genes in trophoblast lineages and impaired formation of the maternal-foetal interface in the placental labyrinth. Using Sox2-Cre to delete Dnmt3b in the embryo, leaving expression intact in placental cells, the placental phenotype was rescued and, consequently, the embryonic lethality, as Dnmt3b null embryos could now survive to birth. We conclude that de novo DNA methylation by DNMT3B during embryogenesis is principally required to regulate placental development and function, which in turn is critical for embryo survival.
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Metilación de ADN , ADN Metiltransferasa 3A , Embarazo , Femenino , Animales , Ratones , Placentación , Placenta/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , Epigénesis GenéticaRESUMEN
The mechanism governing the transition of human embryonic stem cells (hESCs) toward differentiated cells is only partially understood. To explore this transition, the activity and expression of the ubiquitous phosphatidylinositol 3-kinase (PI3Kα and PI3Kß) were modulated in primed hESCs. The study reports a pathway that dismantles the restraint imposed by the EZH2 polycomb repressor on an essential stemness gene, NODAL, and on transcription factors required to trigger primitive streak formation. The primitive streak is the site where gastrulation begins to give rise to the three embryonic cell layers from which all human tissues derive. The pathway involves a PI3Kß non-catalytic action that controls nuclear/active RAC1 levels, activation of JNK (Jun N-terminal kinase) and nuclear ß-catenin accumulation. ß-Catenin deposition at promoters triggers release of the EZH2 repressor, permitting stemness maintenance (through control of NODAL) and correct differentiation by allowing primitive streak master gene expression. PI3Kß epigenetic control of EZH2/ß-catenin might be modulated to direct stem cell differentiation.
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Células Madre Embrionarias , Proteína Potenciadora del Homólogo Zeste 2 , Fosfatidilinositol 3-Quinasas , Línea Primitiva , beta Catenina , Diferenciación Celular/genética , Células Madre Embrionarias/citología , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Expresión Génica , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , beta Catenina/genética , beta Catenina/metabolismoRESUMEN
In all eutherian mammals, growth of the fetus is dependent upon a functional placenta, but whether and how the latter adapts to putative fetal signals is currently unknown. Here, we demonstrate, through fetal, endothelial, hematopoietic, and trophoblast-specific genetic manipulations in the mouse, that endothelial and fetus-derived IGF2 is required for the continuous expansion of the feto-placental microvasculature in late pregnancy. The angiocrine effects of IGF2 on placental microvasculature expansion are mediated, in part, through IGF2R and angiopoietin-Tie2/TEK signaling. Additionally, IGF2 exerts IGF2R-ERK1/2-dependent pro-proliferative and angiogenic effects on primary feto-placental endothelial cells ex vivo. Endothelial and fetus-derived IGF2 also plays an important role in trophoblast morphogenesis, acting through Gcm1 and Synb. Thus, our study reveals a direct role for the imprinted Igf2-Igf2r axis on matching placental development to fetal growth and establishes the principle that hormone-like signals from the fetus play important roles in controlling placental microvasculature and trophoblast morphogenesis.
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Factor II del Crecimiento Similar a la Insulina/metabolismo , Placenta/irrigación sanguínea , Receptor IGF Tipo 2/metabolismo , Animales , Línea Celular , Proteínas de Unión al ADN/genética , Células Endoteliales/metabolismo , Femenino , Desarrollo Fetal , Feto/metabolismo , Factor II del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/fisiología , Ratones , Ratones Endogámicos C57BL , Microvasos/metabolismo , Neovascularización Fisiológica/fisiología , Placenta/metabolismo , Placenta/fisiología , Placentación , Embarazo , Receptor IGF Tipo 2/fisiología , Factores de Transcripción/genética , Trofoblastos/metabolismoRESUMEN
Two recently developed models, trophoblast organoids and trophoblast stem cells (TSCs), are useful tools to further the understanding of human placental development. Both differentiate from villous cytotrophoblast (VCT) to either extravillous trophoblast (EVT) or syncytiotrophoblast (SCT). Here, we compare the transcriptomes and miRNA profiles of these models to identify which trophoblast they resemble in vivo. Our findings indicate that TSCs do not readily undergo SCT differentiation and closely resemble cells at the base of the cell columns from where EVT derives. In contrast, organoids are similar to VCT and undergo spontaneous SCT differentiation. A defining feature of human trophoblast is that VCT and SCT are human leukocyte antigen (HLA) null, whereas EVT expresses HLA-C, -G and -E molecules. We find that trophoblast organoids retain these in vivo characteristics. In contrast, TSCs express classical HLA-A and HLA-B molecules, and maintain their expression after EVT differentiation, with upregulation of HLA-G. Furthermore, HLA expression in TSCs differs when grown in 3D rather than in 2D, suggesting that mechanical cues are important. Our results can be used to select the most suitable model for the study of trophoblast development, function and pathology.
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Modelos Biológicos , Trofoblastos/citología , Técnicas de Cultivo de Célula , Diferenciación Celular , Células Cultivadas , Femenino , Antígenos HLA/genética , Antígenos HLA/metabolismo , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Organoides/citología , Organoides/crecimiento & desarrollo , Organoides/metabolismo , Placentación , Embarazo , Células Madre/citología , Células Madre/metabolismo , Transcriptoma , Trofoblastos/metabolismoRESUMEN
Normal function of the placenta depends on the earliest developmental stages when trophoblast cells differentiate and invade into the endometrium to establish the definitive maternal-fetal interface. Previously, we identified the ubiquitously expressed tumour suppressor BRCA1-associated protein 1 (BAP1) as a central factor of a novel molecular node controlling early mouse placentation. However, functional insights into how BAP1 regulates trophoblast biology are still missing. Using CRISPR/Cas9 knockout and overexpression technology in mouse trophoblast stem cells, here we demonstrate that the downregulation of BAP1 protein is essential to trigger epithelial-mesenchymal transition (EMT) during trophoblast differentiation associated with a gain of invasiveness. Moreover, we show that the function of BAP1 in suppressing EMT progression is dependent on the binding of BAP1 to additional sex comb-like (ASXL1/2) proteins to form the polycomb repressive deubiquitinase (PR-DUB) complex. Finally, both endogenous expression patterns and BAP1 overexpression experiments in human trophoblast stem cells suggest that the molecular function of BAP1 in regulating trophoblast differentiation and EMT progression is conserved in mice and humans. Our results reveal that the physiological modulation of BAP1 determines the invasive properties of the trophoblast, delineating a new role of the BAP1 PR-DUB complex in regulating early placentation.
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Transición Epitelial-Mesenquimal/genética , Proteínas Represoras/genética , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Animales , Diferenciación Celular/genética , Regulación de la Expresión Génica , Humanos , Ratones , Proteínas Represoras/metabolismo , Trofoblastos/fisiología , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina Tiolesterasa/metabolismoRESUMEN
Transient receptor potential (TRP) channels play prominent roles in ion homeostasis by their ability to control cation influx. Mouse placentation is governed by the processes of trophoblast proliferation, invasion, differentiation, and fusion, all of which require calcium signaling. Although certain TRP channels have been shown to contribute to maternal-fetal transport of magnesium and calcium, a role for TRP channels in specific trophoblast functions has been disregarded. Using qRT-PCR and in situ hybridisation, the spatio-temporal expression pattern of TRP channels in the mouse placenta across gestation (E10.5-E18.5) was assessed. Prominent expression was observed for Trpv2, Trpm6, and Trpm7. Calcium microfluorimetry in primary trophoblast cells isolated at E14.5 of gestation further revealed the functional activity of TRPV2 and TRPM7. Finally, comparing TRP channels expression in mouse trophoblast stem cells (mTSCs) and mouse embryonic stem cells (mESC) confirmed the specific expression of TRPV2 during placental development. Moreover, TRP channel expression was similar in mTSCs compared to primary trophoblasts and validate mTSC as a model to study TRP channels in placental development. Collectivity, our results identify a specific spatio-temporal TRP channel expression pattern in trophoblasts, suggesting a possible involvement in regulating the process of placentation.
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Placenta/metabolismo , Placentación/genética , Canales de Potencial de Receptor Transitorio/metabolismo , Animales , Canales de Calcio/genética , Canales de Calcio/metabolismo , Señalización del Calcio , Diferenciación Celular , Proliferación Celular , Femenino , Regulación de la Expresión Génica , Ratones , Ratones Endogámicos C57BL , Células Madre Embrionarias de Ratones/citología , Células Madre Embrionarias de Ratones/metabolismo , Embarazo , Células Madre/citología , Células Madre/metabolismo , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo , Canales de Potencial de Receptor Transitorio/genética , Trofoblastos/citología , Trofoblastos/metabolismoRESUMEN
A fully functional placenta is critical for a successful pregnancy. In this issue of Developmental Cell, Singh et al. reveal that excessive placental DNA damage in murine models for Cornelia de Lange syndrome results in an inefficient and senescent placenta that impairs embryonic development.
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Síndrome de Cornelia de Lange , Animales , Daño del ADN , Femenino , Ratones , Placenta , EmbarazoRESUMEN
Reproductive decline in older female mice can be attributed to a failure of the uterus to decidualise in response to steroid hormones. Here, we show that normal decidualisation is associated with significant epigenetic changes. Notably, we identify a cohort of differentially methylated regions (DMRs), most of which gain DNA methylation between the early and late stages of decidualisation. These DMRs are enriched at progesterone-responsive gene loci that are essential for reproductive function. In female mice nearing the end of their reproductive lifespan, DNA methylation fidelity is lost at a number of CpG islands (CGIs) resulting in CGI hypermethylation at key decidualisation genes. Importantly, this hypermethylated state correlates with the failure of the corresponding genes to become transcriptionally upregulated during the implantation window. Thus, age-associated DNA methylation changes may underlie the decidualisation defects that are a common occurrence in older females. Alterations to the epigenome of uterine cells may therefore contribute significantly to the reproductive decline associated with advanced maternal age.
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Envejecimiento/genética , Implantación del Embrión/genética , Epigénesis Genética/fisiología , Reproducción/fisiología , Animales , Células Cultivadas , Islas de CpG/genética , Metilación de ADN/fisiología , Decidua/fisiología , Embrión de Mamíferos , Femenino , Masculino , Edad Materna , Ratones , Ratones Endogámicos C57BL , Embarazo , Reproducción/genéticaRESUMEN
Studies suggest that placental nutrient supply adapts according to fetal demands. However, signaling events underlying placental adaptations remain unknown. Here we demonstrate that phosphoinositide 3-kinase p110α in the fetus and the trophoblast interplay to regulate placental nutrient supply and fetal growth. Complete loss of fetal p110α caused embryonic death, whilst heterozygous loss resulted in fetal growth restriction and impaired placental formation and nutrient transport. Loss of trophoblast p110α resulted in viable fetuses, abnormal placental development and a failure of the placenta to transport sufficient nutrients to match fetal demands for growth. Using RNA-seq we identified genes downstream of p110α in the trophoblast that are important in adapting placental phenotype. Using CRISPR/Cas9 we showed loss of p110α differentially affects gene expression in trophoblast and embryonic stem cells. Our findings reveal important, but distinct roles for p110α in the different compartments of the conceptus, which control fetal resource acquisition and growth.
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Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Células Madre Embrionarias/enzimología , Metabolismo Energético , Desarrollo Fetal , Placentación , Trofoblastos/enzimología , Animales , Femenino , Feto , Ratones , Embarazo , Transducción de SeñalRESUMEN
The placenta is the chief regulator of nutrient supply to the growing embryo during gestation. As such, adequate placental function is instrumental for developmental progression throughout intrauterine development. One of the most common complications during pregnancy is insufficient growth of the fetus, a problem termed intrauterine growth restriction (IUGR) that is most frequently rooted in a malfunctional placenta. Together with conventional gene targeting approaches, recent advances in screening mouse mutants for placental defects, combined with the ability to rapidly induce mutations in vitro and in vivo by CRISPR-Cas9 technology, has provided new insights into the contribution of the genome to normal placental development. Most importantly, these data have demonstrated that far more genes are required for normal placentation than previously appreciated. Here, we provide a summary of common types of placental defects in established mouse mutants, which will help us gain a better understanding of the genes impacting on human placentation. Based on a recent mouse mutant screen, we then provide examples on how these data can be mined to identify novel molecular hubs that may be critical for placental development. Given the close association between placental defects and abnormal cardiovascular and brain development, these functional nodes may also shed light onto the etiology of birth defects that co-occur with placental malformations. Taken together, recent insights into the regulation of mouse placental development have opened up new avenues for research that will promote the study of human pregnancy conditions, notably those based on defects in placentation that underlie the most common pregnancy pathologies such as IUGR and pre-eclampsia.
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Large-scale phenotyping efforts have demonstrated that approximately 25-30% of mouse gene knockouts cause intrauterine lethality. Analysis of these mutants has largely focused on the embryo and not the placenta, despite the crucial role of this extraembryonic organ for developmental progression. Here we screened 103 embryonic lethal and sub-viable mouse knockout lines from the Deciphering the Mechanisms of Developmental Disorders program for placental phenotypes. We found that 68% of knockout lines that are lethal at or after mid-gestation exhibited placental dysmorphologies. Early lethality (embryonic days 9.5-14.5) is almost always associated with severe placental malformations. Placental defects correlate strongly with abnormal brain, heart and vascular development. Analysis of mutant trophoblast stem cells and conditional knockouts suggests that a considerable number of factors that cause embryonic lethality when ablated have primary gene function in trophoblast cells. Our data highlight the hugely under-appreciated importance of placental defects in contributing to abnormal embryo development and suggest key molecular nodes that govern placenta formation.
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Pérdida del Embrión/genética , Pérdida del Embrión/patología , Mutación , Placenta/patología , Placentación/genética , Animales , Femenino , Ratones , Ratones Noqueados , Embarazo , Células Madre/metabolismo , Células Madre/patología , Trofoblastos/metabolismo , Trofoblastos/patologíaRESUMEN
The ten-eleven translocation (TET) proteins are well known for their role in maintaining naive pluripotency of embryonic stem cells. Here, we demonstrate that, jointly, TET1 and TET2 also safeguard the self-renewal potential of trophoblast stem cells (TSCs) and have partially redundant roles in maintaining the epithelial integrity of TSCs. For the more abundantly expressed TET1, we show that this is achieved by binding to critical epithelial genes, notably E-cadherin, which becomes hyper-methylated and downregulated in the absence of TET1. The epithelial-to-mesenchymal transition phenotype of mutant TSCs is accompanied by centrosome duplication and separation defects. Moreover, we identify a role of TET1 in maintaining cyclin B1 stability, thereby acting as facilitator of mitotic cell-cycle progression. As a result, Tet1/2 mutant TSCs are prone to undergo endoreduplicative cell cycles leading to the formation of polyploid trophoblast giant cells. Taken together, our data reveal essential functions of TET proteins in the trophoblast lineage.
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Ciclo Celular , Proteínas Proto-Oncogénicas/metabolismo , Células Madre/citología , Células Madre/metabolismo , Trofoblastos/citología , Animales , Línea Celular , Forma del Núcleo Celular , Centrosoma/metabolismo , Ciclina B1/metabolismo , Endorreduplicación , Células Epiteliales/metabolismo , Transición Epitelial-Mesenquimal , Regulación de la Expresión Génica , Técnicas de Inactivación de Genes , Humanos , Poliploidía , Estabilidad ProteicaRESUMEN
Mammalian reproductive performance declines rapidly with advanced maternal age. This effect is largely attributed to the exponential increase in chromosome segregation errors in the oocyte with age. Yet many pregnancy complications and birth defects that become more frequent in older mothers, in both humans and mice, occur in the absence of karyotypic abnormalities. Here, we report that abnormal embryonic development in aged female mice is associated with severe placentation defects, which result from major deficits in the decidualisation response of the uterine stroma. This problem is rooted in a blunted hormonal responsiveness of the ageing uterus. Importantly, a young uterine environment can restore normal placental as well as embryonic development. Our data highlight the pivotal, albeit under-appreciated, impact of maternal age on uterine adaptability to pregnancy as major contributor to the decline in reproductive success in older females.Advanced maternal age has been associated with lower reproductive success and higher risk of pregnancy complications. Here the authors show that maternal ageing-related embryonic abnormalities in mouse are caused by decidualisation and placentation defects that can be rescued by transferring the embryo from an old to a young uterus.
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Envejecimiento/fisiología , Decidua/fisiopatología , Placenta/fisiopatología , Reproducción/fisiología , Factores de Edad , Envejecimiento/genética , Animales , Células Cultivadas , Decidua/metabolismo , Desarrollo Embrionario/genética , Desarrollo Embrionario/fisiología , Femenino , Perfilación de la Expresión Génica/métodos , Humanos , Masculino , Edad Materna , Ratones Endogámicos C57BL , Placenta/metabolismo , Placentación/genética , Embarazo , Complicaciones del Embarazo/genética , Complicaciones del Embarazo/fisiopatología , Reproducción/genética , Útero/metabolismo , Útero/fisiopatologíaRESUMEN
Gene expression data are accumulating exponentially in public repositories. Reanalysis and integration of themed collections from these studies may provide new insights, but requires further human curation. Here we report a crowdsourcing project to annotate and reanalyse a large number of gene expression profiles from Gene Expression Omnibus (GEO). Through a massive open online course on Coursera, over 70 participants from over 25 countries identify and annotate 2,460 single-gene perturbation signatures, 839 disease versus normal signatures, and 906 drug perturbation signatures. All these signatures are unique and are manually validated for quality. Global analysis of these signatures confirms known associations and identifies novel associations between genes, diseases and drugs. The manually curated signatures are used as a training set to develop classifiers for extracting similar signatures from the entire GEO repository. We develop a web portal to serve these signatures for query, download and visualization.
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Critical roles for DNA methylation in embryonic development are well established, but less is known about its roles during trophoblast development, the extraembryonic lineage that gives rise to the placenta. We dissected the role of DNA methylation in trophoblast development by performing mRNA and DNA methylation profiling of Dnmt3a/3b mutants. We find that oocyte-derived methylation plays a major role in regulating trophoblast development but that imprinting of the key placental regulator Ascl2 is only partially responsible for these effects. We have identified several methylation-regulated genes associated with trophoblast differentiation that are involved in cell adhesion and migration, potentially affecting trophoblast invasion. Specifically, trophoblast-specific DNA methylation is linked to the silencing of Scml2, a Polycomb Repressive Complex 1 protein that drives loss of cell adhesion in methylation-deficient trophoblast. Our results reveal that maternal DNA methylation controls multiple differentiation-related and physiological processes in trophoblast via both imprinting-dependent and -independent mechanisms.