A number of key regulators of mouse embryonic stem (ES) cell identity, including the transcription factor Nanog, show strong expression fluctuations at the single cell level. The molecular basis for these fluctuations is unknown. Here we used a genetic complementation strategy to investigate expression changes during transient periods of Nanog downregulation. Employing an integrated approach, that includes high-throughput single cell transcriptional profiling and mathematical modelling, we found that early molecular changes subsequent to Nanog loss are stochastic and reversible. However, analysis also revealed that Nanog loss severely compromises the self-sustaining feedback structure of the ES cell regulatory network. Consequently, these nascent changes soon become consolidated to committed fate decisions in the prolonged absence of Nanog. Consistent with this, we found that exogenous regulation of Nanog-dependent feedback control mechanisms produced more a homogeneous ES cell population. Taken together our results indicate that Nanog-dependent feedback loops play a role in controlling both ES cell fate decisions and population variability.
Nanog-dependent feedback loops regulate murine embryonic stem cell heterogeneity.
Specimen part
View SamplesAlthough nuclear transfer allows the reprogramming of somatic cells to totipotency, little is known concerning the kinetics by which it takes place or the minimum requirements for its success. Here, we demonstrate that reprogramming can be achieved within a few hours and a single cell-cycle as long as two key constraints on reprogramming are satisfied. First, the recipient cell chromosomes must be removed during mitosis. Second, the nuclear envelope of the donor cell must be broken down and its chromosomes condensed, allowing an embryonic nucleus to be constructed around the incoming chromosomes. If these requirements are not met, then reprogramming fails and embryonic development arrests. These results point to a central role for processes intimately linked to cell division in mediating efficient transitions between transcriptional programs.
Reprogramming within hours following nuclear transfer into mouse but not human zygotes.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Human oocytes reprogram somatic cells to a pluripotent state.
Specimen part
View SamplesGene expression of sibling human ES cell lines are more similar to each other than unrelated cell lines.
Optimal timing of inner cell mass isolation increases the efficiency of human embryonic stem cell derivation and allows generation of sibling cell lines.
Specimen part
View SamplesThe exchange of the oocyte's genome with the genome of a somatic cell, followed by the derivation of pluripotent stem cells, could enable the generation of specific cell types affected in degenerative human diseases. Such cells, carrying the patient's genome, might be useful for cell replacement. Here we report that the development of human oocytes activated after genome exchange invariably arrests at the late cleavage stages in association with transcriptional abnormalities. In contrast, if the oocyte genome is not removed and the somatic cell genome is merely added, they efficiently develop to the blastocyst stage. Human stem cell lines derived from these blastocysts differentiate into cell types of all three germ layers, and a pluripotent gene expression program is established on the genome derived from the somatic cell. This result demonstrates the feasibility of reprogramming human cells using oocytes and identifies the removal of the oocyte genome as the primary cause of developmental failure after genome exchange. Future work should focus on the critical elements that are associated with the human oocyte genome.
Human oocytes reprogram somatic cells to a pluripotent state.
Specimen part
View SamplesThe exchange of the oocytes genome with the genome of a somatic cell, followed by the derivation of pluripotent stem cells, could enable the generation of specific cell types affected in degenerative human diseases. Such cells, carrying the patients genome, might be useful for cell replacement. Here we report that the development of human oocytes activated after genome exchange invariably arrests at the late cleavage stages in association with transcriptional abnormalities. In contrast, if the oocyte genome is not removed and the somatic cell genome is merely added, they efficiently develop to the blastocyst stage. Human stem cell lines derived from these blastocysts differentiate into cell types of all three germ layers, and a pluripotent gene expression program is established on the genome derived from the somatic cell. This result demonstrates the feasibility of reprogramming human cells using oocytes and identifies the removal of the oocyte genome as the primary cause of developmental failure after genome exchange. Future work should focus on the critical elements that are associated with the human oocyte genome.
Human oocytes reprogram somatic cells to a pluripotent state.
Specimen part
View SamplesBreast cancer (BRC) is the most invasive cancer in women. Although the survival rate of BRC is gradually increasing due to improved screening systems, development of novel therapeutic targets for inhibition of BRC proliferation, metastasis and recurrence have been constantly needed. Thus, in this study, we identified overexpression of SETDB1, a histone methyltransferase, in RNA-seq data of BRC derived from TCGA portal. In Gene Ontology (GO) analysis, cell migration-related GO terms were enriched, and we confirmed down-regulation of cell migration/invasion and alteration of EMT /MET markers after knockdown of SETDB1. Moreover, gene network analysis showed that SMAD7 expression is regulated by SETDB1 levels, indicating that up-regulation of SMAD7 by SETDB1 knockdown inhibited BRC metastasis. Therefore, development of SETDB1 inhibitors and functional studies may help develop more effective clinical guidelines for BRC treatment
No associated publication
Sex, Age, Specimen part, Disease, Cell line, Treatment
View SamplesNPTX1 is a key inducer of neural lineages from the human ESC.
NPTX1 regulates neural lineage specification from human pluripotent stem cells.
Cell line, Time
View SamplesNicotinamide (NAM) inhibited the expression of Age related macular degeneration (AMD) associated proteins in hiPSC-derived retinal pigment epithelium (RPE).
No associated publication
Disease, Treatment
View SamplesDuring development, lineage specification is controlled by several signaling pathways involving various transcription factors (TFs). Here, we studied the RE1-silencing transcription factor (REST) and identified an important role of this TF in cardiac differentiation. Using mouse embryonic stem cells (ESC) to model development, we analyzed the effect of REST knock-out on the ability to these cells to differentiate into the cardiac lineage. Detailed analysis of specific lineage markers expression showed selective down-regulation of endoderm markers in REST-null cells, thus contributing to a loss of cardiogenic signals.
A Role for RE-1-Silencing Transcription Factor in Embryonic Stem Cells Cardiac Lineage Specification.
Specimen part, Treatment
View Samples