In birds and mammals, all mesoderm cells are generated from the primitive streak. Nascent mesoderm cells contain unique dorso-ventral (D/V) identities depending on their relative ingression position along the streak. Molecular mechanisms controlling this initial phase of mesoderm diversification are not well-understood. Using chick model, we generated high-quality transcriptomic datasets of different streak regions and analyzed their molecular heterogeneity.
Transcriptomic landscape of the primitive streak.
Specimen part
View SamplesThe neuroectoderm is patterned along a rostral-caudal axis in response to localized factors in the embryo, but exactly how these factors act as positional information for this patterning is not yet fully understood. Here, using the self-organizing properties of mouse embryonic stem cell (ESC), we report that ESC-derived neuroectoderm self-generates a Six3+ rostral and a Irx3+ caudal bipolarized patterning. In this instance, localized Fgf signaling performs dual roles, as it regulates Six3+ rostral polarization at an earlier stage and promotes Wnt signaling at a later stage. The Wnt signaling components are differentially expressed in the polarized tissues, leading to genome-wide Irx3+ caudal-polarization signals. Surprisingly, differentially expressed Wnt agonists and antagonists have essential roles in orchestrating the formation of a balanced rostral-caudal neuroectoderm pattern. Together, our findings provide key processes for dynamic self-patterning and evidence that a temporally and locally regulated interaction between Fgf and Wnt signaling controls self-patterning in ESC-derived neuroectoderm.
Self-patterning of rostral-caudal neuroectoderm requires dual role of Fgf signaling for localized Wnt antagonism.
Specimen part
View SamplesThe epiblast (foremost embryonic ectoderm) generates all three germ layers and therefore has crucial roles in the formation of all mammalian body cells. Regulation of epiblast gene expression is poorly understood due to the difficulty of manipulating epiblast tissues in vivo. In the present study, using the self-organizing properties of embryonic stem cells (ESCs), we generated and characterized epiblast-like tissue in three-dimensional (3D) culture. We identified significant genome-wide expression changes in this epiblast-like tissue. Additionally, we identified the significance of the Fgf/Erk and ectoderm formation pathways, using the bioinformatics resource IPA and DAVID. We first focused on Fgf5, which ranked in the top 10 among discovered genes. Toward functional analysis of Fgf5, we developed efficient methods of genome engineering (CRISPR/Cas9) and RNA interference (RNAi). Notably, we show one-step generation of an Fgf5 reporter line, null and in/del mutants. Furthermore, mutation types correlated well with CRISPR/Cas9 activity. For time- and dose-dependent depletion of Fgf5 over the course of development, we generated an ESC line harboring a drug-inducible short hairpin RNA cassette integrated by the Tol2 transposon system (pRNAi). Our methods provide a framework for a broad array of applications in the areas of mammalian genetics and molecular biology to understand development and to improve future therapeutics.
Establishment of Functional Genomics Pipeline in Mouse Epiblast-Like Tissue by Combining Transcriptomic Analysis and Gene Knockdown/Knockin/Knockout, Using RNA Interference and CRISPR/Cas9.
Specimen part
View SamplesCellular diversity of the brain is largely attributed to the spatial and temporal heterogeneity of progenitor cells. In mammalian cerebral development, it has been difficult to determine how neural progenitor cells are heterogeneous, due to their dynamic changes in nuclear position and gene expression. To address this issue, we systematically analyzed the cDNA profiles of a large number of single progenitor cells at the mid-embryonic stage.
Single-cell gene profiling defines differential progenitor subclasses in mammalian neurogenesis.
Specimen part
View SamplesDuring cerebral development, a variety of neurons are sequentially generated by self-renewing progenitor cells, apical progenitors (APs). A temporal change in AP identity is thought to produce a diversity of progeny neurons, while underlying mechanisms are largely unknown. Here we performed single cell genome-wide transcriptome profiling of APs at different neurogenic stages, and identified a set of genes that are temporally expressed in APs in a manner independent of differentiation state. Surprisingly, the temporal pattern of such AP gene expression was not affected by arresting cell cycling. Consistently, a transient cell cycle arrest of APs in vivo did not prevent descendant neurons to acquire their correct laminar fates. in vitro cell culture of APs revealed that transitions in AP gene expression involved in both cell-autonomous and non-autonomous mechanisms. These results suggest that timers controlling AP temporal identity run independently of cell cycle progression and Notch activation mode.
Cell-cycle-independent transitions in temporal identity of mammalian neural progenitor cells.
Specimen part
View SamplesLiving organisms detect seasonal changes in day length (photoperiod), and alter their physiological functions accordingly, to fit seasonal environmental changes. This photoperiodic system is implicated in seasonal affective disorders and the season-associated symptoms observed in bipolar disease and schizophrenia. Thyroid-stimulating hormone beta subunit (Tshb), induced in the pars tuberalis (PT), plays a key role in the pathway that regulates animal photoperiodism. However, the upstream inducers of Tshb expression remain unknown. Here we show that late-night light stimulation acutely triggers the Eya3-Six1 pathway, which directly induces Tshb expression. Using melatonin-proficient CBA/N mice, which preserve the photoperiodic Tshb-expression response, we performed a genome-wide expression analysis of the PT under chronic short-day and long-day conditions. These data comprehensively identified long-day and short-day genes, and indicated that late-night light stimulation induces long-day genes. We verified this by advancing and extending the light period by 8 hours, which acutely induced Tshb expression, within one day. In a genome-wide expression analysis under this condition, we searched for candidate upstream genes by looking for expression that preceded Tshbs, and identified Eya3 gene. These results elucidate the comprehensive transcriptional photoperiodic response in the PT, revealing the complex regulation of Tshb expression and unexpectedly rapid response to light changes in the mammalian photoperiodic system.
Acute induction of Eya3 by late-night light stimulation triggers TSHβ expression in photoperiodism.
Sex, Age, Specimen part, Time
View SamplesSince Japanese quail and chicken belong to the same order Galliforms, DNA sequence of both species are highly conserved and proved to be applicable for various analyses each other. Quail are commonly used to address physiological questions for reasons of economy.
Thyrotrophin in the pars tuberalis triggers photoperiodic response.
No sample metadata fields
View SamplesThe FANTOM5 promoter expression atlas provides a rich source of expression and functional annotation of human and mouse cell-type specific transcriptomes with wide applications in biomedical research.
An atlas of human long non-coding RNAs with accurate 5' ends.
No sample metadata fields
View SamplesDendritic cells (DCs) are critical regulators of Foxp3+ regulatory T (Treg) cell-homeostasis. Recent reports have suggested that Langerin+ DCs, especially epidermal Langerhans cells (LCs), play an important role in inducing Treg cells. We investigated the roles of Langerin+ DCs in expanding Treg cells after ultraviolet B (UVB) exposure. We found that Treg cells were expanded in UVB-exposed skin in vivo even without Langerin+ DCs including LCs. In the UVB-exposed skin, Langerin- DCs showed a mature phenotype, and the Treg-expansion induced by UVB was significantly abrogated by CD86/CD80 blockade. Thus, maturing Langerin- DCs, rather than LCs and Langerin+ dermal DCs, are the main contributors to UVB-induced Treg expansion in the skin. These results indicate that a new mechanism for UVB-mediated tolerance, which can provide a new concept of treatment using DC-mediated tolerance.
Ultraviolet B-Induced Maturation of CD11b-Type Langerin<sup>-</sup> Dendritic Cells Controls the Expansion of Foxp3<sup>+</sup> Regulatory T Cells in the Skin.
Specimen part, Cell line
View SamplesA/J mice are genetically predisposed to spontaneous and/or chemically-induced lung tumors while C57BL/6J (B6) mice are resistant. This genetic disparity provides a unique scenario to identify molecular mechanisms associated with the lung response to welding fume at the transcriptome level.
Response of the mouse lung transcriptome to welding fume: effects of stainless and mild steel fumes on lung gene expression in A/J and C57BL/6J mice.
Treatment
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