ABSTRACT: Satb1 and Satb2 are regulators of higher order chromatin in T cells and osteoblasts repectively. We were interested if Satb1 and Satb2 play a role in the regulation of gene expression in ES cells. This SuperSeries is composed of the following subset Series: GSE17487: Expression data in WT and Satb1-/- ES cells GSE17488: Expression data in WT and ES cells overexpressing Satb1 GSE17489: Expression data in WT and ES cells overexpressing Satb2 Refer to individual Series
Project description:Satb1 and Satb2 are regulators of higher order chromatin in T cells and osteoblasts repectively. We were interested if Satb1 and Satb2 play a role in the regulation of gene expression in ES cells. In this experiment, we compared the transcriptome of wild type and Satb1-/- ES cells. Interestingly Satb1-/- ES cells display an impaired differentiation potential. WT and Satb1-/- ES cells were grown for 3 days in the presence of LIF and selected for Oct4-expression cells by the addition of hygromycin to the culture medium. Previously the cells had been engineered so that they contain a selectable HygroTK reporter in the the Oct4 locus. Total RNA was harvested and used for hybridization.
Project description:Satb1 and Satb2 are regulators of higher order chromatin in T cells and osteoblasts repectively. We were interested if Satb1 and Satb2 play a role in the regulation of gene expression in ES cells. In this experiment, we compared the transcriptome of wild type and Satb1-/- ES cells. Interestingly Satb1-/- ES cells display an impaired differentiation potential.
Project description:Satb1 and Satb2 are regulators of higher order chromatin in T cells and osteoblasts repectively. We were interested if Satb1 and Satb2 play a role in the regulation of gene expression in ES cells. ES cells which can inducibly express Satb1 or Satb2 were generated using the tet-ON system. In this experiment, we compared gene expression in uninduced cells to that in cells which had been induced for 24h to express Satb2 ectopcially at very high levels.
Project description:Satb1 and Satb2 are regulators of higher order chromatin in T cells and osteoblasts repectively. We were interested if Satb1 and Satb2 play a role in the regulation of gene expression in ES cells. ES cells which can inducibly express Satb1 or Satb2 were generated using the tet-ON system. In this experiment, we compared gene expression in uninduced cells to that in cells which had been induced for 24h to express Satb1 ectopcially at very high levels.
Project description:Satb1 and Satb2 are regulators of higher order chromatin in T cells and osteoblasts repectively. We were interested if Satb1 and Satb2 play a role in the regulation of gene expression in ES cells. This SuperSeries is composed of the SubSeries listed below.
Project description:The non-coding Xist RNA triggers silencing of one of the two female X chromosomes during X inactivation in mammals. Gene silencing by Xist is restricted to special developmental contexts found in cells of the early embryo and specific hematopoietic precursors. The absence of critical silencing factors might explain why Xist cannot silence outside these contexts. Here, we show that Xist can also initiate silencing in a lymphoma model. Using the tumor context we identify the special AT rich binding protein SATB1 as an essential silencing factor. We show that loss of SATB1 in tumor cells abrogates the silencing function of Xist. In normal female lymphocytes Xist localizes along SATB1 filaments and, importantly, forced Xist expression can relocalize SATB1 into the Xist cluster. This reciprocal influence on localization suggests a molecular interaction between Xist and SATB1. SATB1 and its close homologue SATB2 are expressed during the initiation window for X inactivation in embryonic stem cells and are recruited to surround the Xist cluster. Furthermore, ectopic expression SATB1 or SATB2 enables gene silencing by Xist in embryonic fibroblasts, which normally do not provide an initiation context. Thus, SATB1 functions as a crucial initiation factor and may act to organize genes for silencing by Xist during the initiation of X inactivation. Experiment Overall Design: Normal mouse thymus, tumor, and XIST resistant tumor tissue was hybridized on the Affymetrix Mouse430_2 chip. All groups consist of triplicates.
Project description:The chromatin organizers Satb1 and Satb2 regulate developmental genes in a tissue- and locus-specific manner. In mouse Embryonic Stem Cells (mESCs), the Satb proteins are involved in the balance between pluripotency and differentiation by direct control of key developmental factors such as Nanog and a number of Hox genes. Despite their structural similarities, the Satb proteins regulate mESC pluripotency in opposing ways: Satb1 promotes differentiation by repressing Nanog and activating the neural genes Bcl2 and Nestin, while Satb2 supports the pluripotent state by activating Nanog and repressing Satb1. To further address the mechanisms by which the Satb proteins regulate gene expression, we examined the conjugation of Satb2 with the small ubiquitin-like modifier (SUMO) in pluripotent and differentiated mESCs. We describe for the first time the endogenous SUMOylation of Satb2 in mESCs as a response to developmental cues. We found that Satb2 is progressively SUMO2-modified during differentiation of ESCs towards ectodermal precursors. Moreover, we identified Zfp451 as a SUMO E3 ligase able to interact with and modify Satb2 with SUMO2 in vitro and in vivo. Ablation of Zfp451 or mutation of the SUMO-acceptor lysines in the Satb2 protein disrupt the ability of mESCs to efficiently shut-down pluripotency genes and activate the differentiation program. Importantly, forced expression of SUMO2-Satb2 N-terminal fusions rescues the differentiation defect of SUMO-Satb2 deficient mESCs. Mechanistically, SUMOylation reduces binding of Satb2 to a subset of loci associated to pluripotency genes and changes the composition of Satb2-containing complexes in chromatin. Taken together, our data suggests that SUMO modification of the chromatin organizer Satb2 by the E3 ligase Zfp451 is required for the efficient downregulation of pluripotency genes and initiation of the differentiation program in mouse embryonic stem cells.
Project description:The chromatin organizers Satb1 and Satb2 regulate developmental genes in a tissue- and locus-specific manner. In mouse Embryonic Stem Cells (mESCs), the Satb proteins are involved in the balance between pluripotency and differentiation by direct control of key developmental factors such as Nanog and a number of Hox genes. Despite their structural similarities, the Satb proteins regulate mESC pluripotency in opposing ways: Satb1 promotes differentiation by repressing Nanog and activating the neural genes Bcl2 and Nestin, while Satb2 supports the pluripotent state by activating Nanog and repressing Satb1. To further address the mechanisms by which the Satb proteins regulate gene expression, we examined the conjugation of Satb2 with the small ubiquitin-like modifier (SUMO) in pluripotent and differentiated mESCs. We describe for the first time the endogenous SUMOylation of Satb2 in mESCs as a response to developmental cues. We found that Satb2 is progressively SUMO2-modified during differentiation of ESCs towards ectodermal precursors. Moreover, we identified Zfp451 as a SUMO E3 ligase able to interact with and modify Satb2 with SUMO2 in vitro and in vivo. Ablation of Zfp451 or mutation of the SUMO-acceptor lysines in the Satb2 protein disrupt the ability of mESCs to efficiently shut-down pluripotency genes and activate the differentiation program. Importantly, forced expression of SUMO2-Satb2 N-terminal fusions rescues the differentiation defect of SUMO-Satb2 deficient mESCs. Mechanistically, SUMOylation reduces binding of Satb2 to a subset of loci associated to pluripotency genes and changes the composition of Satb2-containing complexes in chromatin. Taken together, our data suggests that SUMO modification of the chromatin organizer Satb2 by the E3 ligase Zfp451 is required for the efficient downregulation of pluripotency genes and initiation of the differentiation program in mouse embryonic stem cells.
Project description:The chromatin organizers Satb1 and Satb2 regulate developmental genes in a tissue- and locus-specific manner. In mouse Embryonic Stem Cells (mESCs), the Satb proteins are involved in the balance between pluripotency and differentiation by direct control of key developmental factors such as Nanog and a number of Hox genes. Despite their structural similarities, the Satb proteins regulate mESC pluripotency in opposing ways: Satb1 promotes differentiation by repressing Nanog and activating the neural genes Bcl2 and Nestin, while Satb2 supports the pluripotent state by activating Nanog and repressing Satb1. To further address the mechanisms by which the Satb proteins regulate gene expression, we examined the conjugation of Satb2 with the small ubiquitin-like modifier (SUMO) in pluripotent and differentiated mESCs. We describe for the first time the endogenous SUMOylation of Satb2 in mESCs as a response to developmental cues. We found that Satb2 is progressively SUMO2-modified during differentiation of ESCs towards ectodermal precursors. Moreover, we identified Zfp451 as a SUMO E3 ligase able to interact with and modify Satb2 with SUMO2 in vitro and in vivo. Ablation of Zfp451 or mutation of the SUMO-acceptor lysines in the Satb2 protein disrupt the ability of mESCs to efficiently shut-down pluripotency genes and activate the differentiation program. Importantly, forced expression of SUMO2-Satb2 N-terminal fusions rescues the differentiation defect of SUMO-Satb2 deficient mESCs. Mechanistically, SUMOylation reduces binding of Satb2 to a subset of loci associated to pluripotency genes and changes the composition of Satb2-containing complexes in chromatin. Taken together, our data suggests that SUMO modification of the chromatin organizer Satb2 by the E3 ligase Zfp451 is required for the efficient downregulation of pluripotency genes and initiation of the differentiation program in mouse embryonic stem cells.
Project description:β-Catenin is the major co-regulator of the Wnt signalling pathway. β-Catenin lysine 49 is post-translationally modified. The histone methyl transferase Ezh2 trimethylates β-catenin at lysine 49 and the acetyl transferase Cbp acetylates β-catenin at the same lysine. To determine the effects on gene expression embryonic stem cells containing either a Gfp tagged β-catenin wildtype (wt) or lysine 49 to alanine (K49A) loss of function mutation were analysed by micro array expression profiling. To determine the effects on gene expression in the pluripotent state two biological replicates of Gfp β-catenin wt and Gfp β-catenin K49A were analysed. The results showed that genes which affect pluripotency as well as differentiation were altered by β-catenin K49A mutation. To analyse the effects of gene expression during ES cell differentiation ES cells containing Gfp β-catenin wt or K49A were differentiated into mesodermal progenitors (mp) and neuronal progenitors (np). Two biological replicates were analysed by micro array expression profiling. Differentially expressed genes between Gfp β-catenin wt and K49A during differentiation were observed. Mesodermal marker genes like t-brachyury and cdx2 were not upregulated in mesodermal differentiation of Gfp β-catenin K49A Es cells.