Lgr5+ adult intestinal stem cells are highly proliferative throughout life. Single Lgr5+ stem cells can be cultured into 3D epithelial organoids containing all cell types at nearnormal ratios. Culture conditions to generate the main cell types have been established previously, but signals inducing the various types of enteroendocrine cells (EECs) have remained elusive. Here we generate quiescent Lgr5+ stem cells in vitro by inhibition of the EGF-receptor (EGFR) and mitogen-associated protein kinase (MAPK) signaling pathways in organoids, a state that can be readily reversed. Quiescent Lgr5+ stem cells gain a distinct molecular signature, biased towards EEC differentiation. Indeed, combined inhibition of Wnt, Notch and MAPK pathways efficiently generates a diversity of EEC subtypes in vitro. Our observations uncouple Wnt-dependent stem cell maintenance from EGF-dependent proliferation and cell fate choice, and provide an in vitro approach for the study of the elusive EECs. Overall design: We established a stable culture of quiescent Lgr5+ intestinal stem cells in culture. These highly resemble quiescent secretory precursors, which has high EEC differentiation potential. Following on this lead, we elucidated what signals are required to generate EEC cells of all varieties, and provide a method to produce these EEC cells in large numbers.
Induced Quiescence of Lgr5+ Stem Cells in Intestinal Organoids Enables Differentiation of Hormone-Producing Enteroendocrine Cells.
Specimen part, Cell line, Subject
View SamplesUnderstanding the development and function of an organ requires the characterization of all of its cell types. Traditional methods for visualizing and isolating sub-populations of cells are based on mRNA or protein expression of only few known marker genes. The unequivocal identification of a specific marker gene, however, poses a major challenge, particularly if this cell type is rare. Identifying rare cell types, such as stem cells, short-lived progenitors, cancer stem cells, or circulating tumor cells is crucial to acquire a better understanding of normal or diseased tissue biology. To address this challenge we sequenced the transcriptome of hundreds of randomly selected cells from mouse intestinal organoids, cultured self-organizing epithelial structures that contain all cell lineages of the mammalian intestine. Organoid buds, like intestinal crypts, harbor stem cells that continuously differentiate into a variety of cell types, occurring at widely different abundances. Since available computational methods can only resolve more abundant cell types, we developed RaceID, an algorithm for rare cell type identification in complex populations of single cells. We demonstrate that this algorithm can resolve cell types represented by only a single cell in a population of randomly sampled organoid cells. We use this algorithm to identify Reg4 as a novel marker for enteroendocrine cells, a rare population of hormone producing intestinal cells. Next, we use Reg4 expression to enrich for these rare cells and investigate the heterogeneity within this population. Reassuringly, RaceID confirmed the existence of known enteroendocrine lineages, and moreover, discovered novel subtypes, which we subsequently validated in vivo. Having validated RaceID by this proof-of-principle experiment we then apply the algorithm to ex vivo isolated LGR5 positive cells and their direct progeny and demonstrate homogeneity of the stem cell pool. We envision broad applicability of our method for discovering rare cell types and the corresponding marker genes in healthy and diseased organs. Overall design: Small intestinal crypts were isolated from a single wild-type C57BL/6 mouse, a Reg4-dsRed-knock-in mouse and an Lgr5-GFP-DTR mouse. The crypts were propagated and expanded in culture as organoids. For each experiment, multiple organoids were harvested and dissociated into single cells. Each experiment was done twice, using different passage of the same organoid culture. We also included a pool-and-split control for 96 Reg4-dsRed positive intetsinal cells and a control library with 5 mouse embryonic stem cells (wells 1-5), 5 mouse embryonic fibroblasts (wells 6-10), 75 random organoid cells (wells 11-85), 5 wells without primer and without template (wells 86 and 93-96), and five wells with primer and without template (wells 87-92). We also sequenced two 96 well plates of Lgr5-EGFP positive single cells isolated ex vivo, and Lgr5 progeny collected after five days of lineage tracing. Label induction was performed using an Lgr5-Cre reporter mouse expressing YFP from Rosa26 promoter with a loxP flanked transcriptional road block in between. Five 96 well plates of YFP positive were sequenced. Sample number four also contains also unrelated samples (single cell barcode 49-96), which should be discarded.
Single-cell messenger RNA sequencing reveals rare intestinal cell types.
No sample metadata fields
View SamplesTo understand organ (dys)function it is important to have a complete inventory of its cell types and the corresponding markers that unambiguously identify these cell types. This is a challenging task, in particular in human tissues, because unique cell-type markers are typically unavailable, necessitating the analysis of complex cell type mixtures. Transcriptome-wide studies on pancreatic tissue are typically done on pooled islet material. To overcome this challenge we sequenced the transcriptome of thousands of single pancreatic cells from deceased organ donors with and without type 2 diabetes (T2D) allowing in silico purification of the different cell types. We identified the major pancreatic cell types resulting in the identification of many new cell-type specific and T2D-specific markers. Additionally we observed several subpopulations within the canonical pancreatic cell types, which we validated in situ. This resource will be useful for developing a deeper understanding of pancreatic biology and diabetes mellitus. Overall design: Human cadaveric pancreata were used to extract islets of Langerhans, which were kept in culture until single-cell dispersion and FACS sorting. Single-cell transcriptomics was performed on live cells from this mixture using CEL-seq or on cells stained for CD63, CD13, TGFBR3 or CD24 and CD44. The RaceID algorithm was used to identify clusters of cells corresponding to the major pancreatic cell types and to mine for novel cell type-specific genes as well as subpopulations within the known pancreatic cell types.
De Novo Prediction of Stem Cell Identity using Single-Cell Transcriptome Data.
Specimen part, Subject
View SamplesPaneth cells (PCs) are long-lived secretory cells that reside at the bottoms of small intestinal crypts. Besides serving as niche cells for the neighboring Lgr5-positive stem cells, PCs secrete granules containing a broad spectrum of antimicrobial proteins, including lysozymes and defensins1. Here, we have used single-cell RNA sequencing to explore PC differentiation. We found a maturation gradient from early secretory progenitors to mature PCs, capturing the full maturation path of PCs. Moreover, differential expression of a subset of defensin genes in lysozyme-high PCs, e.g. Defa20, reveals at least two distinct stages of maturation. Overall design: We traced Lgr5+ stem cells from Lgr5-CreERT2 C57Bl6/J mice bred to a Rosa26LSL-YFP reporter mice and sorted YFP+ cells 5 days, 3 weeks and 8 weeks after tamoxifen injection.
De Novo Prediction of Stem Cell Identity using Single-Cell Transcriptome Data.
Specimen part, Cell line, Subject
View SamplesGerm plasm, the Balbiani body and nuage are evolutionary conserved structures essential for germ cell specification and maintenance. We describe Tdrd6a as a component of these structures with two distinct molecular functions. First, Tdrd6a facilitates the accumulation of the typical antisense-bias of piRNAs, without having effects on piRNA biogenesis signatures. Second, we show that Tdrd6a is required for Balbiani body and germ plasm integrity, and associates with RNA-binding proteins and germ plasm mRNAs. On the cell-biological level, maternally contributed Tdrd6a strongly impacts germ cell formation, but is dispensable for fertility. Using single-cell RNA-sequencing we demonstrate that Tdrd6a promotes early germ cell development and regulates the stoichiometry of germ plasm mRNAs. We propose that Tdrd6a functions as a scaffold to recruit correct ratios of germ plasm transcripts and to accumulate antisense piRNA complexes in order to ensure both specification and maintenance of germ cells. Overall design: Single cell were sorted directly in Trizolfrom embryos spawned by mz tdrd6a-/- mother and wt mother carrying a kop::egfp-f-nos1-3'UTR transgene. Thereafter single cell trizol extractio was performed followed by RT, IVT and RNA-seq library prep.
Tdrd6a Regulates the Aggregation of Buc into Functional Subcellular Compartments that Drive Germ Cell Specification.
Cell line, Subject
View SamplesLgr5+ stem cells reside at crypt bottoms of the small and large intestine. Small intestinal Paneth cells supply Wnt3, EGF and Notch signals to neighboring Lgr5+ stem cells. While the colon lacks Paneth cells, Deep Crypt Secretory (DCS) cells are intermingled with Lgr5+ stem cells at crypt bottoms. Here, we report Reg4 as a marker of DCS cells. To investigate a niche function, we eliminated DCS cells using the diphtheria-toxin receptor gene knocked into the murine Reg4 locus. Ablation of DCS cells results in loss of stem cells from colonic crypts and disrupts gut homeostasis and colon mini-gut formation. In agreement, sorted Reg4+ DCS cells promote organoid formation of single Lgr5+ colon stem cells. Stem cells are forced to generate DCS cells in vitro by combined Notch inhibition and Wnt activation. We conclude that Reg4+ DCS cells serve as Paneth cell equivalents in the colon crypt niche. Overall design: To define a global gene expression signature of DCS cells, we performed RNA-sequencing (RNA-seq) of sorted Reg4-dsRed+ and Lgr5-GFP+ cells from colonic epithelium. Sorting and RNA-seq library preparation was performed twice, to obtain a biological replicate.
Reg4+ deep crypt secretory cells function as epithelial niche for Lgr5+ stem cells in colon.
No sample metadata fields
View SamplesIn industrial fermentations of Saccharomyces cerevisiae, transient changes in oxygen concentration commonly occur and it is important to understand the behaviour of cells during these changes. Saccharomyces cerevisiae CEN.PK113-1A was grown in glucose-limited chemostat culture with 1.0% and 20.9% O2 in the inlet gas (D= 0.10 /h, pH5, 30C). After steady state was achieved, oxygen was replaced with nitrogen and cultures were followed until new steady state was achieved. The overall responses to anaerobic conditions of cells initially in different conditions were very similar. Independent of initial culture conditions, transient downregulation of genes related to growth and cell proliferation, mitochondrial translation and protein import, and sulphate assimilation was seen. In addition, transient or permanent upregulation of genes related to protein degradation, and phosphate and amino acid uptake was observed in all cultures. However, only in the initially oxygen-limited cultures was a transient upregulation of genes related to fatty acid oxidation, peroxisomal biogenesis, oxidative phosphorylation, TCA cycle, response to oxidative stress, and pentose phosphate pathway observed. Furthermore, from the initially oxygen-limited conditions, a rapid response around the metabolites of upper glycolysis and the pentose phosphate pathway was seen, while from the initially fully aerobic conditions, a slower response around the pathways for utilisation of respiratory carbon sources was observed.
Transcriptional responses of Saccharomyces cerevisiae to shift from respiratory and respirofermentative to fully fermentative metabolism.
Time
View SamplesIn most embryos, the mid-blastula transition is a complex process featuring maternal RNA degradation, cell cycle pause, zygotic transcriptional activation and morphological changes. The nucleocytoplasmic (N/C) ratio has been proposed to control the multiple events at MBT. To understand the global transcriptional response to the changes of the N/C ratio, we profiled wild type and haploid embryos using cDNA microarrays at three developmental stages.
Coupling of zygotic transcription to mitotic control at the Drosophila mid-blastula transition.
No sample metadata fields
View SamplesKaposis sarcoma-associated hepesvirus (KSHV) encodes four genes with homology to human interferon regulatory factors (IRFs). One of these IRFs, the viral interferon regulatory factor 3 (vIRF-3) is expressed in latently infected PEL cells and required for their continuous proliferation. Moreover, vIRF-3 is known to be involved in modulation of the type I interferon response.
Kaposi's sarcoma-associated herpesvirus viral interferon regulatory factor 3 inhibits gamma interferon and major histocompatibility complex class II expression.
Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Promoter-proximal transcription factor binding is transcriptionally active when coupled with nucleosome repositioning in immediate vicinity.
Specimen part, Disease, Cell line
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