We explored the relationship between Myc activity and PI3K signaling in ESCs. Our data demonstrate that Myc and PI3K signaling function cooperatively for supporting pluripotent property of ESCs. Moreover, our data demonstrate that exposure of ESCs to 2i condition render both Myc and PI3K dispensable for preserving ESC status.
Functional compensation between Myc and PI3K signaling supports self-renewal of embryonic stem cells.
Sex, Specimen part
View Samplesc-Myc is one of key players that are crucially involved in maintaining the undifferentiated state and the self-renewal of ESCs. To understand the mechanism by which c-Myc helps preserve these prominent characteristics of ESCs, we generated null-ES cells for the Max gene, which encodes the best characterized partner protein for all Myc family proteins. Although Myc/Max complexes have been widely regarded as crucial regulators of the ESC status, our data reveal that ESCs do not absolutely require these complexes in so-called ground state or related conditons and that this requirement is restricted to conventional ES culture conditions without using a MAPK inhibitor.
Indefinite self-renewal of ESCs through Myc/Max transcriptional complex-independent mechanisms.
Sex, Specimen part
View SamplesPartial induced pluripotent cells (iPSCs) are cell lines strayed from normal route from somatic cells to iPSCs and are immortalized. Mouse partial iPSCs are able to convert to real iPSCs by the exposure to 2i condition using MAPK and GSK3? inhibitors. However, the molecular mechanisms of this conversion are totally not known. Our piggyback vector mediated genome-wide screen revealed that Cnot2, one of core components of Ccr4-Not complex participates in this conversion. Subsequent analyses revealed other core components, i.e., Cnot1 and Cnot3 and Trim28 which is known to extensively share genomic binding sites with Cnot3 contribute to this conversion as well. Our bioinformatics analyses indicate that the major role of these factors in the conversion is the down-regulation of developmental genes in partial iPSCs.
Identification of Ccr4-not complex components as regulators of transition from partial to genuine induced pluripotent stem cells.
Sex, Specimen part
View SamplesSomatic cell reprogramming can be achieved by cell fusion with embryonic stem cells (ESCs), nuclear transfer into oocytes, or forced expression of transcription factors essential for ESC identity. Reprogramming by transcription factors is a less efficient and slower process than that by other methods. Identification of a gene set capable of driving rapid and proper reprogramming to induced pluripotent stem cells (iPSCs) is an important issue. Here, we show that the efficiency and kinetics of iPSC reprogramming are dramatically improved by combined transduction of Jarid2, a gene highly expressed in both ESCs and oocytes and genes encoding its associated proteins. We demonstrate that forced expression of Jarid2 promotes iPSC reprogramming by suppressing the expression of Arf, a known reprogramming barrier, and that the N-terminal half of JARID2 is sufficient for such promotion. Moreover, Jarid2 accelerated retroviral transgene silencing and Nanog promoter demethylation, confirming its promoting activity. We further reveal that JARID2 physically interacts with ESRRB, SALL4A and PRDM14, and show that these JARID2-associated proteins synergistically and robustly facilitate iPSC reprogramming in a Jarid2-dependent manner. Our findings provide an insight into the important roles of Jarid2 during reprogramming, and suggest that the JARID2-associated protein network contributes to overcoming reprogramming barriers.
No associated publication
Specimen part
View SamplesNucleostemin (NS) gene is known to be expressed in stem cells in general including embryonic stem cells (ESCs). Previous knockdown and knockout studies have demonstrated that NS is important for the preservation of their self-renewality and high levels of pluripotent marker gene expression in mouse ESCs. In this study, we demonstrate that the forced expression of Nanog or Esrrb, but not other pluripotency factors, made NS expression dispensable in mouse ESCs. DNA microarray data deposited here underscored the notion that both Nanog and Esrrb could rather faithfully counteract the alteration of gene expression profile caused by NS expression ablation in ESCs.
Forced expression of Nanog or Esrrb preserves the ESC status in the absence of nucleostemin expression.
Sex, Specimen part
View SamplesWe explored Max ablation-mediated up-regulation of germ-related genes, especially meiosis-related genes in mouse embryonic stem cells which were cultured either under conventional mouse ES medium or 2i condition using inhibitors against MEK and GSK3b.
Loss of MAX results in meiotic entry in mouse embryonic and germline stem cells.
Sex, Specimen part
View SamplesThe aim of this study is to investigate the gene expression profiles during masculinization of neonatal female mice brain by exogenous androgen treatment.
Gene expression profile of the neonatal female mouse brain after administration of testosterone propionate.
Sex, Specimen part, Treatment
View SamplesAblation of expression of the Max gene encoding a Myc protein partner in ES cells provoked two major phenomena, i.e. loss of pluripotency and apoptotic cell death. We found that nicotinamide (Nam) significantly alleviates these Max expression ablation-coupled phenotypes in ES cells. To see the alleviation effect of Nam on the overall expression profile of Max-null ES cells whose Max expression is controlled by the tet-off system, we eliminated Max expression by adding doxycycline (Dox) in the presence of Nam.
Sirt1, p53, and p38(MAPK) are crucial regulators of detrimental phenotypes of embryonic stem cells with Max expression ablation.
Sex, Specimen part, Treatment
View SamplesTo examine the role of Efp in endometrial cancer cells, Ishikawa and HEC-1A cells were treated with siRNA targeting Efp (siEfp) or control siRNA (siControl). Microarray analysis showed that Efp knockdown represses NF-B-signaling pathway-associated genes.
No associated publication
Cell line
View SamplesTo identify novel Peroxisome Proliferator-Activated Receptor gamma (PPARg) responsive secretory and/or transmembrane genes that is related to obesity, we integrated the expression data from the adipose tissue derived from obese mice with the other two data sets: expression profiling of adipocyte differentiation using ST2 cells and siRNA-mediated knockdown of Pparg during ST2 cell adipogenesis.
Fam57b (family with sequence similarity 57, member B), a novel peroxisome proliferator-activated receptor γ target gene that regulates adipogenesis through ceramide synthesis.
Specimen part
View Samples