Transcription profiling of chicken Bcl6 deficient DT40 B cell line to investigate the targets of Bcl6 which is required for germinal center formation
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ABSTRACT: The transcription factor Bcl6 is required for germinal center formation and deregulated expression of Bcl6 has been observed in lymphomas. To gain insight to the function of Bcl6 in terminal differentiation of B cells to plasma cells and to investigate the targets of Bcl6, we established a Bcl6 deficient DT40 B cell line.
Project description:Transcription profiling of chicken Pax5 deficient DT40 B cell line to investigate the targets of Pax5 which is required for B-cell differentiation Used in cross-species comparison to investigate evolutionarily conserved regulatory circuits in B cell development Pax5 deficient DT40 B cells (3 biological replicates) were compared to DT40 wild-type cells (3 biological replicates).
Project description:PAx5 is indispensible for the committment if early lymphoid progenitors to the B cell lineage as well as for the development and maintenance of B cells. To better understand the functional importance of Pax5 in the later stages of B cell development and investigate the targets of Pax5 regulation, we established a novel Pax5 deficient DT40 B cell line.
Project description:Our data demonstrated that Bcl6 directly binds and represses trafficking receptors S1pr1 and Grp183 by recruiting Hdac2 through the RD2 domain. Deregulation of these genes impairs B-cell migration and may contribute to the Germinal Center failure in Bcl6RD2MUT mice. RNAseq was performed in endogenous BCL6-depleted OCI-LY1 cells rescued with either WT or RD mutant BCL6 (N=3 for each group).
Project description:T follicular helper (Tfh) cells play a pivotal role in germinal center reactions, which requires Bcl6 transcription factor. To analyze their relationships with other effector T cell lineages and their stability in vivo, we developed and analyzed a new Bcl6 reporter mouse alone or together with other lineage reporter systems. Assisted with genome-wide transcriptome analysis, we show substantial plasticity of T cell differentiation in the early phase of immune response. At this stage, CXCR5 appears to be expressed in a Bcl6-independent manner. Once Bcl6 is highly expressed, Tfh cells can persist in vivo and some of them develop into memory cells. Together, our results indicate Bcl6 as a bona fide marker for Tfh polarized program. Three group of samples, with 2 biological replicates within each group and total of 6 samples were analyzed.
Project description:To determine whether BCL6 binds to the certain locus we performed genomic localization studies by chromatin immunoprecipitations (ChIP) using a densely tiled custom oligonucleotide microarray covering the genomic loci of different genes. Keywords: ChIP-chip, Transcription Factor localization The experiment was performed in Ramos cell. Triplicate ChIP with BCL6 or actin (negative control) antibodies were cohybridized to the arrays versus the respective input chromatin.The fold enrichment for each oligonucleotide was calculated as the ratio of Cy5 vs. Cy3. Any peaks involving >5 oligonucleotides and with > 2.5 fold enrichment were considered potentially positive hits.
Project description:The Philadelphia chromosome (Ph) encodes the oncogenic BCR-ABL1 tyrosine kinase, which defines a subset of acute lymphoblastic leukemia (ALL) with a particularly unfavorable prognosis. Tyrosine kinase inhibitors (TKI) are widely used to treat patients with leukemia driven by BCR-ABL1 and other oncogenic tyrosine kinases. In response to TKI-treatment, BCR-ABL1 ALL cells upregulate BCL6 protein levels by ~90-fold, i.e. to similar levels as in diffuse large B cell lymphoma (DLBCL) with BCL6 translocations. In this study, we used genome tiling arrays to identify BCL6 target genes with specific recruitment of BCL6. Three Ph+ ALL cell lines (BV-173, NALM-1 and TOM-1) in duplicate were either treated with 10µM STI571 (Imatinib) for 24 hours or cultured in absence of STI571.
Project description:This SuperSeries is composed of the following subset Series: GSE24381: Inhibition of BCL6-dependent gene expression in Philadelphia chromosome positive acute lymphoblastic leukemia GSE24404: Recruitment of BCL6 to target genes in Philadelphia chromosome positive acute lymphoblastic leukemia Refer to individual Series
Project description:We identified the BCL6 protooncogene as a critical downstream effector of FoxO3A in self-renewal signaling of CML-initiating cells. BCL6 represses Arf and p53 in CML cells and is required for leukemia stem cell maintenance, colony formation and initiation of leukemia in transplant recipients. Importantly, peptide inhibition of BCL6 in human CML cells compromises colony formation and leukemia-initiation in xenotransplanted mouse recipients. These findings identify peptide-inhibition of BCL6 as a novel strategy to eradicate leukemia-initiating cells in CML. Identification of BCL6 binding sites in human CML cell line JURL-MK1
Project description:Identification BCL6 target genes in primary germinal center cells and DLBCL cell lines by ChIP-on-chip Three replicates in each type of cells