Cultured pluripotent stem cells are a cornerstone of regenerative medicine due to their ability to give rise to all cell types of the body. While pluripotent stem cells can be propagated indefinitely in vitro, pluripotency is paradoxically a very transient state in vivo, lasting 2-3 days around the time of blastocyst implantation. The exception to this rule is embryonic diapause, a reversible state of suspended development triggered by unfavorable conditions. Diapause is a strategy widely employed across the animal kingdom, including in mammals, but its regulation remains poorly understood. Here we report that inhibition of mechanistic target of rapamycin (mTor), a major nutrient sensor and promoter of growth, induces reversible pausing of mouse blastocyst development and allows their prolonged culture ex vivo. Paused blastocysts remain pluripotent and competent to give rise to embryonic stem (ES) cells and mice. We show that both natural diapause blastocysts in vivo and paused blastocysts ex vivo display pronounced reductions in mTor activity, translation and transcription. In addition, pausing can be induced directly in cultured ES cells and sustained for weeks in the absence of cell death or deviations from cell cycle distributions. We show that paused ES cells remain pluripotent, display a remarkable global suppression of transcription, and maintain a gene expression signature of diapaused blastocysts. These results allow for the first time the sustained suspension of development of a mammalian embryo in the laboratory, and shed light on the regulation of diapause and the origins of ES cells. Our findings have important implications in the fields of assisted reproduction, regenerative medicine, cancer, metabolic disorders and aging. Overall design: Examination of RNA expression profiles of embryonic stem cells in serum, 2i and paused states by RNA-seq
Inhibition of mTOR induces a paused pluripotent state.
Specimen part, Cell line, Treatment, Subject
View SamplesRoberts syndrome (RBS) is a human developmental disorder caused by mutations in the cohesin acetyltransferase ESCO2. We previously reported that mTORC1 was inhibited and overall translation was reduced in RBS cells. Treatment of RBS cells with L-leucine partially rescued mTOR function and protein synthesis, correlating with increased cell division. In this study, we use RBS as a model for mTOR inhibition and analyze transcription and translation with ribosome profiling to determine genome-wide effects of L-leucine. The translational efficiency of many genes is increased with Lleucine in RBS cells including genes involved in ribosome biogenesis, translation, and mitochondrial function. snoRNAs are strongly upregulated in RBS cells, but decreased with L-leucine. Imprinted genes, including H19 and GTL2, are differentially expressed in RBS cells consistent with contribution to mTORC1 control. This study reveals dramatic effects of L-leucine stimulation of mTORC1 and supports that ESCO2 function is required for normal gene expression and translation. Overall design: 42 samples of human fibroblast cell lines with various genotypes (wt, corrected, and esco2 mutants) are treated with l-leucine or d-leucine (control) for 3 or 24 hours. Biological replicates are present.
Improved transcription and translation with L-leucine stimulation of mTORC1 in Roberts syndrome.
No sample metadata fields
View SamplesMultiple regulatory regions have the potential to regulate a single gene, yet how these elements combine to impact gene expression remains unclear. To uncover the combinatorial relationships between enhancers, we developed Enhancer-interference (Enhancer-i), a CRISPR interference-based approach that can prevent enhancer activation simultaneously at multiple regulatory regions. We applied Enhancer-i to promoter-distal estrogen receptor a binding sites (ERBS), which cluster around estradiol-responsive genes and therefore may collaborate to regulate gene expression. Targeting individual sites revealed predominant ERBS that are completely required for the transcriptional response, indicating a lack of redundancy. Simultaneous interference of different ERBS combinations identified supportive ERBS that contribute only when predominant sites are active. Using mathematical modeling, we find strong evidence for collaboration between predominant and supportive ERBS. Overall, our findings expose a complex functional hierarchy of enhancers, where multiple loci bound by the same transcription factor combine to fine tune the expression of target genes. Overall design: The effects of Enhancer interference (Enhancer-i) and control guide RNA treatment on the transcriptome before and after estrogen treatment, with 2 replicates per condition.
Multiplex Enhancer Interference Reveals Collaborative Control of Gene Regulation by Estrogen Receptor α-Bound Enhancers.
Specimen part, Treatment, Subject
View SamplesCohesinopathies are characterized by mutations in the cohesin complex. Mutations in NIPBL, a cohesin loader, result in Cornelia de Lange syndrome (CdLS). CdLS is a congenital genetic disorder distinguished by craniofacial dysmorphism, abnormal upper limb development, delayed growth, severe cognitive retardation, and multiple organ malformations.It has been suggested that CdLS is caused by defects in the cohesin network that alter gene expression and genome organization. However, the precise molecular etiology of CdLS is largely unclear. To gain insights, we sequenced mRNAs isolated from mouse embryonic fibroblasts of both WT and NIPBL-haploinsufficient mice and compared their transcriptomes. Overall design: Examination of gene expression of WT and NIPBL+/- mice by RNA-seq
NIPBL Controls RNA Biogenesis to Prevent Activation of the Stress Kinase PKR.
No sample metadata fields
View SamplesCondensin complexes are highly conserved for chromosome compaction to ensure their faithful segregation in mitosis. Condensin II is present in the nucleus throughout the cell cycle, including interphase. The aim of these experiments is to investigate the changes of gene expression in knockdown of NCAPH2, a condensin II subunit, in mouse embryonic stem cells compared to their control cells. Overall design: Examination of gene expression of controls and NCAPH2 knockdown cells by RNA-seq
Condensin II is anchored by TFIIIC and H3K4me3 in the mammalian genome and supports the expression of active dense gene clusters.
Specimen part, Subject
View SamplesEstrogen receptor alpha (ESR1) mutations have been identified in hormone therapy resistant breast cancer and primary endometrial cancer. Analyses in breast cancer suggests that mutant ESR1 exhibits estrogen independent activity. In endometrial cancer, ESR1 mutations are associated with worse outcomes and less obesity, however experimental investigation of these mutations has not been performed. Using a unique CRISPR/Cas9 strategy, we introduced the D538G mutation, a common endometrial cancer mutation that alters the ligand binding domain of ESR1, while epitope tagging the endogenous locus. We discovered estrogen-independent mutant ESR1 genomic binding that is significantly altered from wildtype ESR1. The D538G mutation impacted expression, including a large set of non-estrogen regulated genes, and chromatin accessibility, with most affected loci bound by mutant ESR1. Mutant ESR1 is unique from constitutive ESR1 activity as mutant-specific changes are not recapitulated with prolonged estrogen exposure. Overall, D538G mutant ESR1 confers estrogen-independent activity while causing additional regulatory changes in endometrial cancer cells that are distinct from breast cancer cells. Overall design: RNA-seq was used to study the effects of the D538G mutation on gene expression
Estrogen-independent molecular actions of mutant estrogen receptor 1 in endometrial cancer.
Cell line, Treatment, Subject, Time
View SamplesBackground: Degenerative disc disease (DDD) is a primary contributor to low back pain, a leading cause of disability. Progression of DDD is aided by inflammatory cytokines in the intervertebral disc (IVD), particularly TNF-a and IL-1ß, but current treatments fail to effectively target this mechanism. The objective of this study was to explore the feasibility of CRISPR epigenome editing based therapy for DDD, by modulation of TNFR1/IL1R1 signaling in pathological human IVD cells. Methods: Human IVD cells from the nucleus pulposus of patients receiving surgery for back pain were obtained and the regulation of TNFR1/IL1R1 signaling by a lentiviral CRISPR epigenome editing system was tested. These cells were tested for successful lentiviral transduction/expression of dCas9-KRAB system and regulation of TNFR1/IL1R1 expression. TNFR1/IL1R1 signaling disruption was investigated via measurement of NF-?B activity, apoptosis, and anabolic/catabolic changes in gene expression post inflammatory challenge. Results: CRISPR epigenome editing systems were effectively introduced into pathological human IVD cells and significantly downregulated TNFR1 and IL1R1. This downregulation significantly attenuated deleterious TNFR1 signaling but not IL1R1 signaling. This is attributed to less robust IL1R1 expression downregulation, and IL-1ß driven reversal of IL1R1 expression downregulation in a portion of patient IVD cells. Additionally, RNAseq data indicated a novel transcription factor targets, IRF1 and TFAP2C, as being a primary regulators of inflammatory signaling in IVD cells. Discussion: These results demonstrate the feasibility of CRISPR epigenome editing of inflammatory receptors in pathological IVD cells, but highlight a limitation in epigenome targeting of IL1R1. This method has potential application as a novel gene therapy for DDD, to attenuate the deleterious effect of inflammatory cytokines present in the degenerative IVD. Overall design: Patient nucleus pulposus cells (TNFR1kd and nontargeting control) were analyzed by RNA-seq with and without TNF-a treatment.
Lentiviral CRISPR Epigenome Editing of Inflammatory Receptors as a Gene Therapy Strategy for Disc Degeneration.
Sex, Age, Specimen part, Treatment, Subject
View SamplesSteroid hormone receptors are simultaneously active in many tissues and capable of altering each other's function. Estrogen receptor ? (ER) and glucocorticoid receptor (GR) are expressed in the uterus and their ligands have opposing effects on uterine growth. In endometrial tumors expressing high levels of ER, we surprisingly found that expression of GR is associated with poor prognosis. Dexamethasone reduced normal uterine growth in vivo; however, this growth inhibition was abolished in estrogen-induced endometrial hyperplasia. We observed low genomic binding site overlap when ER and GR are induced with their respective ligands; however, upon simultaneous induction they co-occupy more sites. GR binding is significantly altered by estradiol with GR recruited to ER bound loci that become more accessible upon estradiol induction. Gene expression responses to co-treatment were more similar to estradiol, but with novel regulated genes. Our results suggest phenotypic and molecular interplay between ER and GR in endometrial cancer. Overall design: ChIP-seq, ATAC-seq, and RNA-seq data collected from endometrial cancer cell lines induced with dexamethasone, estradiol, or the combination
FFPEcap-seq: a method for sequencing capped RNAs in formalin-fixed paraffin-embedded samples.
Cell line, Treatment, Subject
View SamplesRNA-seq transcriptome measurements are typically performed by isolating RNA from large numbers of cells in culture or tissues. While highly informative, such experiments mask the variability in gene expression patterns that exists between individual cells. To gain insight into the dynamics of gene expression on the level of single-cells, we have carried out the transcriptomes of single-cells from the GM12878 cell line using RNA-seq. Overall design: Single GM12878 cells were picked and RNA-seq libraries were generated using the SMART-seq protocol. We also carried out RNA-seq experiments on pools of 10, 30 and 100 cells, on 100pg and 10ng of total RNA, and on pools of 10 cells that were subsequently split into 10 separate sample and processed as if they were single cells in order to assess technical variation in our experiments.
From single-cell to cell-pool transcriptomes: stochasticity in gene expression and RNA splicing.
No sample metadata fields
View SamplesGoal of the experiment: Analysis of gene expression changes in the cortex, striatum, hippocampus, hypothalamus, Drd2-MSNs and Drd1-MSNs of mice with a postnatal, neuron-specific ablation of GLP or G9a as compared to control mice.
Control of cognition and adaptive behavior by the GLP/G9a epigenetic suppressor complex.
Specimen part
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