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Cell Discovery Oct 2021Paternal life experiences impact offspring health via germline, and epigenetic inheritance provides a potential mechanism. However, global reprogramming during offspring...
Sperm epigenetic alterations contribute to inter- and transgenerational effects of paternal exposure to long-term psychological stress via evading offspring embryonic reprogramming.
Paternal life experiences impact offspring health via germline, and epigenetic inheritance provides a potential mechanism. However, global reprogramming during offspring embryogenesis and gametogenesis represents the largest hurdle to conceptualize it. Yet, detailed characterization of how sperm epigenetic alterations carrying "environmental memory" can evade offspring embryonic reprogramming remains elusive. Here, mice exposed to long-term restraint stress were employed to study the mechanisms underlying inter- and transgenerational effects of paternal exposure to a long-term psychological stress. We found that stress could induce paternal inheritance of reproductive, behavioral, and metabolic disorders. Bisulfite methylation profiling of 18 sperm and 12 embryo samples of three consecutive generations identified inter- and transgenerational inheritance of paternal Differential DNA Methylation Regions (DMRs) at frequencies ~11.36% and 0.48%, respectively. These DMRs related to genes with functional implications for psychological stress response, and tissue inheritance of these DMRs passed paternal disorders epigenetically to offspring. More importantly, these DMRs evaded offspring embryonic reprogramming through erasure and subsequent reestablishment, but not via un-erasure way. Nonetheless, their reestablishment proportions in the primitive streak (E7.5) stage were altered. Furthermore, sncRNA-seq revealed that stress-induced tsRNA, miRNA and rsRNA dysregulation in paternal sperm might play important roles in DMRs occurrence and paternal inheritance. These finding implied that sperm epigenetic alterations contribute to inter- and transgenerational effects of paternal exposure to long-term psychological stress, and highlighted the possible underlying molecular mechanism.
PubMed: 34711814
DOI: 10.1038/s41421-021-00343-5 -
Molecular Biology of the Cell Dec 2021Mesendoderm cells are key intermediate progenitors that form at the early primitive streak (PrS) and give rise to mesoderm and endoderm in the gastrulating embryo. We...
Mesendoderm cells are key intermediate progenitors that form at the early primitive streak (PrS) and give rise to mesoderm and endoderm in the gastrulating embryo. We have identified an interaction between CNOT3 and the cell cycle kinase Aurora B that requires sequences in the NOT box domain of CNOT3 and regulates MAPK/ERK signaling during mesendoderm differentiation. Aurora B phosphorylates CNOT3 at two sites located close to a nuclear localization signal and promotes localization of CNOT3 to the nuclei of mouse embryonic stem cells (ESCs) and metastatic lung cancer cells. ESCs that have both sites mutated give rise to embryoid bodies that are largely devoid of mesoderm and endoderm and are composed mainly of cells with ectodermal characteristics. The mutant ESCs are also compromised in their ability to differentiate into mesendoderm in response to FGF2, BMP4, and Wnt3 due to reduced survival and proliferation of differentiating mesendoderm cells. We also show that the double mutation alters the balance of interaction of CNOT3 with Aurora B and with ERK and reduces phosphorylation of ERK in response to FGF2. Our results identify a potential adaptor function for CNOT3 that regulates the Ras/MEK/ERK pathway during embryogenesis.
Topics: A549 Cells; Animals; Aurora Kinase B; Cell Differentiation; Cell Survival; Cells, Cultured; Endoderm; Extracellular Signal-Regulated MAP Kinases; Female; Humans; Mesoderm; Mice; Mouse Embryonic Stem Cells; Mutation; Phosphorylation; Transcription Factors
PubMed: 34613789
DOI: 10.1091/mbc.E21-02-0089 -
ELife Jul 2021In classical descriptions of vertebrate development, the segregation of the three embryonic germ layers completes by the end of gastrulation. Body formation then...
In classical descriptions of vertebrate development, the segregation of the three embryonic germ layers completes by the end of gastrulation. Body formation then proceeds in a head to tail fashion by progressive deposition of lineage-committed progenitors during regression of the primitive streak (PS) and tail bud (TB). The identification by retrospective clonal analysis of a population of neuromesodermal progenitors (NMPs) contributing to both musculoskeletal precursors (paraxial mesoderm) and spinal cord during axis formation challenged these notions. However, classical fate mapping studies of the PS region in amniotes have so far failed to provide direct evidence for such bipotential cells at the single-cell level. Here, using lineage tracing and single-cell RNA sequencing in the chicken embryo, we identify a resident cell population of the anterior PS epiblast, which contributes to neural and mesodermal lineages in trunk and tail. These cells initially behave as monopotent progenitors as classically described and only acquire a bipotential fate later, in more posterior regions. We show that NMPs exhibit a conserved transcriptomic signature during axis elongation but lose their epithelial characteristicsin the TB. Posterior to anterior gradients of convergence speed and ingression along the PS lead to asymmetric exhaustion of PS mesodermal precursor territories. Through limited ingression and increased proliferation, NMPs are maintained and amplified as a cell population which constitute the main progenitors in the TB. Together, our studies provide a novel understanding of the PS and TB contribution through the NMPs to the formation of the body of amniote embryos.
Topics: Animals; Body Patterning; Cell Differentiation; Chick Embryo; Gene Expression Regulation, Developmental; Mesoderm; Neural Stem Cells; Primitive Streak
PubMed: 34227938
DOI: 10.7554/eLife.64819 -
Nature Cell Biology Jul 2021It is generally accepted that epiblast cells ingress into the primitive streak by epithelial-to-mesenchymal transition (EMT) to give rise to the mesoderm; however, it is...
It is generally accepted that epiblast cells ingress into the primitive streak by epithelial-to-mesenchymal transition (EMT) to give rise to the mesoderm; however, it is less clear how the endoderm acquires an epithelial fate. Here, we used embryonic stem cell and mouse embryo knock-in reporter systems to combine time-resolved lineage labelling with high-resolution single-cell transcriptomics. This allowed us to resolve the morphogenetic programs that segregate the mesoderm from the endoderm germ layer. Strikingly, while the mesoderm is formed by classical EMT, the endoderm is formed independent of the key EMT transcription factor Snail1 by mechanisms of epithelial cell plasticity. Importantly, forkhead box transcription factor A2 (Foxa2) acts as an epithelial gatekeeper and EMT suppressor to shield the endoderm from undergoing a mesenchymal transition. Altogether, these results not only establish the morphogenetic details of germ layer formation, but also have broader implications for stem cell differentiation and cancer metastasis.
Topics: Animals; Blastocyst; Cell Differentiation; Cell Line; Cell Plasticity; Endoderm; Epithelial Cells; Epithelial-Mesenchymal Transition; Gastrulation; Gene Expression Regulation, Developmental; Gestational Age; Hepatocyte Nuclear Factor 3-beta; Mice; Mice, Transgenic; Mouse Embryonic Stem Cells; Phenotype; Snail Family Transcription Factors; Time Factors
PubMed: 34168324
DOI: 10.1038/s41556-021-00694-x -
EMBO Reports Aug 2021Fine-tuned dissolution of pluripotency is critical for proper cell differentiation. Here we show that the mesodermal transcription factor, T, globally affects the...
Fine-tuned dissolution of pluripotency is critical for proper cell differentiation. Here we show that the mesodermal transcription factor, T, globally affects the properties of pluripotency through binding to Oct4 and to the loci of other pluripotency regulators. Strikingly, lower T levels coordinately affect naïve pluripotency, thereby directly activating the germ cell differentiation program, in contrast to the induction of germ cell fate of primed models. Contrary to the effect of lower T levels, higher T levels more severely affect the pluripotency state, concomitantly enhancing the somatic differentiation program and repressing the germ cell differentiation program. Consistent with such in vitro findings, nascent germ cells in vivo are detected in the region of lower T levels at the posterior primitive streak. Furthermore, T and core pluripotency regulators co-localize at the loci of multiple germ cell determinants responsible for germ cell development. In conclusion, our findings indicate that residual pluripotency establishes the earliest and fundamental regulatory mechanism for inductive germline segregation from somatic lineages.
Topics: Cell Differentiation; Cell Separation; Germ Cells; Mesoderm; Transcription Factors
PubMed: 34156139
DOI: 10.15252/embr.202152553 -
The Journal of Veterinary Medical... Aug 2021The large Japanese field mouse (Apodemus speciosus) is a small rodent species endemic to Japan. The genetic characteristics of A. speciosus include different chromosome...
The large Japanese field mouse (Apodemus speciosus) is a small rodent species endemic to Japan. The genetic characteristics of A. speciosus include different chromosome numbers within the same species. Furthermore, A. speciosus has been used in radiation and genetic research. In the present study, a pregnant A. speciosus was obtained, and histochemical analysis of the implanted embryos was performed and compared with the developmental stages of the mouse (Mus musculus). Although there were some differences, the structures of the implanted embryos, including the primitive streak and placenta of A. speciosus were similar to those of mouse. Our study will be important for the construction of a developmental atlas of A. speciosus.
Topics: Animals; Arvicolinae; Female; Japan; Mice; Murinae; Pregnancy
PubMed: 34148913
DOI: 10.1292/jvms.21-0197 -
Development Genes and Evolution Jul 2021The anterior-posterior axis is a central element of the body plan and, during amniote gastrulation, forms through several transient domains with specific morphogenetic...
The anterior-posterior axis is a central element of the body plan and, during amniote gastrulation, forms through several transient domains with specific morphogenetic activities. In the chick, experimentally proven activity of signalling molecules and transcription factors lead to the concept of a 'global positioning system' for initial axis formation whereas in the (mammotypical) rabbit embryo, a series of morphological or molecular domains are part of a putative 'three-anchor-point model'. Because circular expression patterns of genes involved in axis formation exist in both amniote groups prior to, and during, gastrulation and may thus be suited to reconcile these models, the expression patterns of selected genes known in the chick, namely the ones coding for the transcription factors eomes and tbx6, the signalling molecule wnt3 and the wnt inhibitor pkdcc, were analysed in the rabbit embryonic disc using in situ hybridisation and placing emphasis on their germ layer location. Peripheral wnt3 and eomes expression in all layers is found initially to be complementary to central pkdcc expression in the hypoblast during early axis formation. Pkdcc then appears - together with a posterior-anterior gradient in wnt3 and eomes domains - in the epiblast posteriorly before the emerging primitive streak is marked by pkdcc and tbx6 at its anterior and posterior extremities, respectively. Conserved circular expression patterns deduced from some of this data may point to shared mechanisms in amniote axis formation while the reshaping of localised gene expression patterns is discussed as part of the 'three-anchor-point model' for establishing the mammalian body plan.
Topics: Animals; Body Patterning; Gene Expression Regulation, Developmental; Germ Layers; Rabbits; T-Box Domain Proteins; Wnt Proteins
PubMed: 34100128
DOI: 10.1007/s00427-021-00677-w -
PLoS Biology May 2021The heart develops from 2 sources of mesoderm progenitors, the first and second heart field (FHF and SHF). Using a single-cell transcriptomic assay combined with genetic...
The heart develops from 2 sources of mesoderm progenitors, the first and second heart field (FHF and SHF). Using a single-cell transcriptomic assay combined with genetic lineage tracing and live imaging, we find the FHF and SHF are subdivided into distinct pools of progenitors in gastrulating mouse embryos at earlier stages than previously thought. Each subpopulation has a distinct origin in the primitive streak. The first progenitors to leave the primitive streak contribute to the left ventricle, shortly after right ventricle progenitor emigrate, followed by the outflow tract and atrial progenitors. Moreover, a subset of atrial progenitors are gradually incorporated in posterior locations of the FHF. Although cells allocated to the outflow tract and atrium leave the primitive streak at a similar stage, they arise from different regions. Outflow tract cells originate from distal locations in the primitive streak while atrial progenitors are positioned more proximally. Moreover, single-cell RNA sequencing demonstrates that the primitive streak cells contributing to the ventricles have a distinct molecular signature from those forming the outflow tract and atrium. We conclude that cardiac progenitors are prepatterned within the primitive streak and this prefigures their allocation to distinct anatomical structures of the heart. Together, our data provide a new molecular and spatial map of mammalian cardiac progenitors that will support future studies of heart development, function, and disease.
Topics: Animals; Cell Lineage; Female; Gastrula; Gene Expression; Gene Expression Regulation, Developmental; Heart; Heart Atria; Heart Ventricles; Male; Mesoderm; Mice; Mice, Inbred C57BL; Morphogenesis; Primitive Streak; Sequence Analysis, RNA; Single-Cell Analysis
PubMed: 33999917
DOI: 10.1371/journal.pbio.3001200 -
Cell Reports May 2021In the early fetal stage, the gonads are bipotent and only later become the ovary or testis, depending on the genetic sex. Despite many studies examining how sex...
In the early fetal stage, the gonads are bipotent and only later become the ovary or testis, depending on the genetic sex. Despite many studies examining how sex determination occurs from biopotential gonads, the spatial and temporal organization of bipotential gonads and their progenitors is poorly understood. Here, using lineage tracing in mice, we find that the gonads originate from a T primitive streak through WT1 posterior intermediate mesoderm and appear to share origins anteriorly with the adrenal glands and posteriorly with the metanephric mesenchyme. Comparative single-cell transcriptomic analyses in mouse and cynomolgus monkey embryos reveal the convergence of the lineage trajectory and genetic programs accompanying the specification of biopotential gonadal progenitor cells. This process involves sustained expression of epithelial genes and upregulation of mesenchymal genes, thereby conferring an epithelial-mesenchymal hybrid state. Our study provides key resources for understanding early gonadogenesis in mice and primates.
Topics: Adult Stem Cells; Animals; Cell Differentiation; Gonads; Macaca fascicularis; Male; Mice
PubMed: 33951437
DOI: 10.1016/j.celrep.2021.109075 -
International Journal of Molecular... Apr 2021Epithelial-Mesenchymal Transition (EMT) was first discovered during the transition of cells from the primitive streak during embryogenesis in chicks. It was later... (Review)
Review
Epithelial-Mesenchymal Transition (EMT) was first discovered during the transition of cells from the primitive streak during embryogenesis in chicks. It was later discovered that EMT holds greater potential in areas other than the early development of cells and tissues since it also plays a vital role in wound healing and cancer development. EMT can be classified into three types based on physiological functions. EMT type 3, which involves neoplastic development and metastasis, has been the most thoroughly explored. As EMT is often found in cancer stem cells, most research has focused on its association with other factors involving cancer progression, including telomeres. However, as telomeres are also mainly involved in aging, any possible interaction between the two would be worth noting, especially as telomere dysfunction also contributes to cancer and other age-related diseases. Ascertaining the balance between degeneration and cancer development is crucial in cell biology, in which telomeres function as a key regulator between the two extremes. The essential roles that EMT and telomere protection have in aging reveal a potential mutual interaction that has not yet been explored, and which could be used in disease therapy. In this review, the known functions of EMT and telomeres in aging are discussed and their potential interaction in age-related diseases is highlighted.
Topics: Aging; Animals; Biomarkers; Disease Susceptibility; Epithelial-Mesenchymal Transition; Extracellular Matrix; Gene Expression Regulation; Humans; Signal Transduction; Telomere; Telomere Shortening
PubMed: 33918710
DOI: 10.3390/ijms22083888