Project description:FGF-MEK-ERK pathway has been implicated in diverse contexts in development. The pathway involves many autoinhibitory loops, resulting in pulse-like activity patterns. Here, we modulated the ERK activity during cardiac differentiation at the lateral plate mesoderm stage by PD0325901, a potent inhibitor of MEK, which is an upstream effector of ERK. We collected the resulting cell population, both in 2D and 3D, after cardiac specification to analyse how the ERK inhibition during induction affects the cell fate choice.
Project description:The aim of this study is to investigate a role of glycolysis in transcriptional programing of Th17 cells during differentiation. Naïve CD4 T cells were differentiated towards Th17 cells with or without a mild inhibition of glycolysis, and transcriptome signature was analyzed. We found about 200 transcripts were differentially regulated. Further pathway analysis suggested that glycolysis controls genes associated with IL-2/STAT5 signaling during Th17 differentiation. Inhibition of glycolysis resulted in enrichment of genes associated with translational processes and Th17 signature genes.
Project description:This SuperSeries is composed of the following subset Series: GSE34672: Inhibition of the LSD1 (KDM1A) demethylase reactivates the all-trans-retinoic acid differentiation pathway in acute myeloid leukemia [Illumina HumanHT-12 gene expression array] GSE34725: Inhibition of the LSD1 (KDM1A) demethylase reactivates the all-trans-retinoic acid differentiation pathway in acute myeloid leukemia [ChIP-Seq] Refer to individual Series
Project description:The role of FGF-MEK-ERK signalling pathway during embryonic heart development has not been fully elucidated. Here, we inhibited the pathway for 1 day using PD0325901, a MEK inhibitor, at the lateral plate mesoderm stage during cardiac differentiation of human embryonic stem cells. Cells were collected on day 2 (before PD0325901 administration), day 3 and day 8 to determine the effect of a transient FGF-MEK-ERK pathway modulation on the cardiac cell fate choice.
Project description:Embryonic stem cells can self-renew and differentiate, holding great promise for regenerative medicine. They also employ multiple mechanisms to preserve the integrity of their genomes. Nucleotide excision repair, a versatile repair mechanism, removes bulky DNA adducts from the genome. However, the dynamics of the capacity of nucleotide excision repair during stem cell differentiation remain unclear. Here, using immunoslot blot assay, we measured repair rates of UV-induced DNA damage during differentiation of human embryonic carcinoma (NTERA-2) cells into neurons and muscle cells. Our results revealed that the capacity of nucleotide excision repair increases as cell differentiation progresses. We also found that inhibition of the apoptotic signaling pathway has no effect on nucleotide excision repair capacity. Furthermore, RNA-seq-based transcriptomic analysis indicated that expression levels of four core repair factors, xeroderma pigmentosum (XP) complementation group A (XPA), XPC, XPG, and XPF-ERCC1, are progressively up-regulated during differentiation, but not those of replication protein A (RPA) and transcription factor IIH (TFIIH). Together, our findings reveal that increase of nucleotide excision repair capacity accompanies cell differentiation, supported by the up-regulated transcription of genes encoding DNA repair enzymes during differentiation of two distinct cell lineages.
Project description:Vascular disruption following bony injury results in a hypoxic gradient within the wound microenvironment. Nevertheless, the effects of low oxygen tension on osteogenic precursors remain to be fully elucidated. In the present study, we investigated in vitro osteoblast and mesenchymal stem cell differentiation following exposure to 21% O(2) (ambient oxygen), 2% O(2) (hypoxia), and <0.02% O(2) (anoxia). Hypoxia had little effect on osteogenic differentiation. In contrast, short-term anoxic treatment of primary osteoblasts and mesenchymal precursors inhibited in vitro bone nodule formation and extracellular calcium deposition. Cell viability assays revealed that this effect was not caused by immediate or delayed cell death. Microarray profiling implicated down-regulation of the key osteogenic transcription factor Runx2 as a potential mechanism for the anoxic inhibition of differentiation. Subsequent analysis revealed not only a short-term differential regulation of Runx2 and its targets by anoxia and hypoxia, but a long-term inhibition of Runx2 transcriptional and protein levels after only 12-24 h of anoxic insult. Furthermore, we present evidence that Runx2 inhibition may, at least in part, be because of anoxic repression of BMP2, and that restoring Runx2 levels during anoxia by pretreatment with recombinant BMP2 rescued the anoxic inhibition of differentiation. Taken together, our findings indicate that brief exposure to anoxia (but not 2% hypoxia) down-regulated BMP2 and Runx2 expression, thus inhibiting critical steps in the osteogenic differentiation of pluripotent mesenchymal precursors and committed osteoblasts.