Project description:The transcription factor Ikaros represses Notch signaling. Since Ikaros and Notch treanscriptional mediator RBPJ both recognize sequences that contain the same core TGGGAA motif, it was hypothesized that Ikaros represses Notch signaling by targeting Notch response elements and competing with RBPJ for their binding. Here we used the mouse T-cell leukemia cell line T29 to compare the genomic binding profiles of Ikaros and RBPJ by ChIP-seq. The T29 cell line is derived from a Ikaros-deficient T-cell leukemia (Dumortier et al, MCB 26, 209-220, 2006) and exhibits strong Notch activation. We performed two chip-seq experiments with an anti-RBPJ antibody to map RBPJ binding sites. To map Ikaros binding sites, we engineered a T29-derived cell line that expresses a fusion protein between Ikaros and the ligand binding domain of the estrogen receptor (Ik1-ER) which is activated by addition of 4-hydroxy-tamoxifen (4OHT). We used an anti-Ikaros antibody to map the sites bound by Ik1-ER after treatment of the cells with 4OHT. Sequencing were performed with the Illumina GAII sequencer as as single end 36 base pair reads.
Project description:The transcription factor Ikaros represses Notch signaling. Since Ikaros and Notch treanscriptional mediator RBPJ both recognize sequences that contain the same core TGGGAA motif, it was hypothesized that Ikaros represses Notch signaling by targeting Notch response elements and competing with RBPJ for their binding. Here we used the mouse T-cell leukemia cell line T29 to compare the genomic binding profiles of Ikaros and RBPJ by ChIP-seq.
Project description:The mouse Ikaros-deficient thymic lymphoma cell line T29 was transduced with an empty retrovirus (MigR1) or a retrovirus expressing an fusion proein between Ikaros1 and the ligand binding domain of the estrogen receptor. Cells trreated with ethanol or 4-hydroxy-tamoxyfen (4OHT) for 24h were profiled. We used expression of an inducible ersion of the Ikaros protein in an Ikaros-deficient cell line to identify Ikaros-regulated genes
Project description:The mouse Ikaros-deficient thymic lymphoma cell line T29 was transduced with a retrovirus expressing an fusion protein between a dominant-negative form of Mastermind and the ligand binding domain of the estrogen receptor. Cells trreated with Ethanol or 4-hydroxy-tamoxyfen for 24h were profiled. We used expression of an inducible ersion of the dominant negative Mastermind protein in an Ikaros-deficient cell line to identify Notch-regulated genes
Project description:The mouse Ikaros-deficient thymic lymphoma cell line T29 was transduced with a retrovirus expressing an fusion protein between a dominant-negative form of Mastermind and the ligand binding domain of the estrogen receptor. Cells trreated with Ethanol or 4-hydroxy-tamoxyfen for 24h were profiled.
Project description:The mouse Ikaros-deficient thymic lymphoma cell line T29 was transduced with an empty retrovirus (MigR1) or a retrovirus expressing an fusion proein between Ikaros1 and the ligand binding domain of the estrogen receptor. Cells trreated with ethanol or 4-hydroxy-tamoxyfen (4OHT) for 24h were profiled.
Project description:The mouse Ikaros-deficient thymic lymphoma cell line T29 was treated with a gamma-secretase inhibitor or vehicle (DMSO) for 36h and subjected to transcriptome analysis.
Project description:The mouse Ikaros-deficient thymic lymphoma cell line T29 was treated with a gamma-secretase inhibitor or vehicle (DMSO) for 36h and subjected to transcriptome analysis. 4 samples
Project description:The most recurrently mutated oncogene in T-cell acute lymphoblastic leukemia (T-ALL) is NOTCH1. The core Notch complex consists of an ICN protein, a Maml cofactor, and the DNA binding factor Rbpj. The known direct cofactors of Notch appear to act nonselectively, homogeneously driving Notch gene expression functions. It is unclear whether there are direct cofactors of Notch that act selectively and heterogeneously regulate ICN. We discovered that Zmiz1, a Protein Inhibitor of Activated STAT (PIAS)-like coactivator, directly bound ICN1. In order to determine whether this interaction occured at chromatin, we performed ChIP-Seq. We identified significant overlap between ICN1, Rbpj, and Zmiz1 peaks. 75% of overlapping ICN1/Rbpj peaks overlapped with Zmiz1 (HA) peaks (273 peaks). The size of Zmiz1 (HA) peaks had moderate correlation with the size of Rbpj and ICN1 peaks. Like Rbpj and ICN1 peaks, Zmiz1 (HA) peaks were associated with activating H3K27ac, H3K4me1, and H3K4me3 chromatin marks and were devoid of repressive H3K27me3 marks. These data suggest that Zmiz1 is a selective Notch regulator. It co-binds only a subset of ICN1 and Rbpj-regulated sites. Zmiz1, ICN1, Rbpj, histone mehylation ChIP-Seq in murine T-ALL cell line