Genome-wide Myb chromatin occupancy in murine myeloid progenitor cells
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ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE22095 | GEO | 2011/02/23
SECONDARY ACCESSION(S): PRJNA128833
REPOSITORIES: GEO
Similar Datasets
Project description:We report genome-wide pattern of Myb chromatin occupancy in vivo. We used ERMYB, a myeloid progenitor cell line derived by transformation of primary cells by ER-Myb fusion protein, as our model system. In these cells, activation of the ER-Myb fusion protein by estrogen is required to maintain a proliferative progenitor-like phenotype. We performed ChIP-seq with biological duplicate samples from ERMYB cells with Myb either “on” or “off” (i.e. + or - ?-E2 for 6 hr). By comparing enrichment signals between Myb-on, Myb-off and isotype control samples, we identified 7,646 high-confidence Myb binding regions, which can be assigned to 4,892 annotated genes according to their distances to the nearest transcriptional start sites. Examination of Myb chromatin occupany in myeloid cells transformed by a switchable form of Myb
2011-02-23 | E-GEOD-22095 | biostudies-arrayexpress
Project description:We used the ERMYB cell line (Hogg et al., Oncogene 15, p2885-2898, 1997) as our model system to identify genes regulated by Myb using whole genome microarray expression profiling. ERMYB is a myeloid progenitor cell line derived by transformation of primary cells by an activated form of Myb (CT3-Myb) fused to the ligand binding domain of ERα. In these cells, activation of the ER-Myb fusion protein by estrogen is required to maintain a proliferative progenitor-like phenotype. The cells undergo monocytic differentiation when Myb is inactivated by withdrawal of β-estradiol (β-E2). However, re-induction of Myb within 24 hours can almost fully reverse the differentiation process. This feature enabled us to employ a novel kinetic expression profiling strategy, in that we withdrew β-E2 to inactivate Myb for 24 h, then re-added it for another 6 h and monitored the gene expression across this time course. We reasoned that this strategy may be more likely to identify true Myb target genes than conventional approaches in which differential expression is examined only at the endpoint of induction. To exclude genes that might be responsive to ERα and not Myb we used the parent CT3-Myb cell line and measured the expression changes 6hrs after β-E2 withdraw and excluded those few gene that were differentially expressed. Triplicate total RNA samples from ERMYB cells were collected at 0, 6, and 24 hr after β-E2 withdrawal and 6 hr after β-E2 re-addition. Samples were analyzed by Illumina Mouse Whole Genome arrays (WG6). Probe intensities were variance stabilised and normalized by the Lumi package (Du et al., 2008). Differentially expressed genes were identified by the LIMMA package (Smyth, 2004) and then grouped into different classes according to their kinetic profiles.
2011-02-23 | E-GEOD-22486 | biostudies-arrayexpress
Project description:We used the ERMYB cell line (Hogg et al., Oncogene 15, p2885-2898, 1997) as our model system to identify genes regulated by Myb using whole genome microarray expression profiling. ERMYB is a myeloid progenitor cell line derived by transformation of primary cells by an activated form of Myb (CT3-Myb) fused to the ligand binding domain of ERα. In these cells, activation of the ER-Myb fusion protein by estrogen is required to maintain a proliferative progenitor-like phenotype. The cells undergo monocytic differentiation when Myb is inactivated by withdrawal of β-estradiol (β-E2). However, re-induction of Myb within 24 hours can almost fully reverse the differentiation process. This feature enabled us to employ a novel kinetic expression profiling strategy, in that we withdrew β-E2 to inactivate Myb for 24 h, then re-added it for another 6 h and monitored the gene expression across this time course. We reasoned that this strategy may be more likely to identify true Myb target genes than conventional approaches in which differential expression is examined only at the endpoint of induction. To exclude genes that might be responsive to ERα and not Myb we used the parent CT3-Myb cell line and measured the expression changes 6hrs after β-E2 withdraw and excluded those few gene that were differentially expressed.
2011-02-23 | GSE22486 | GEO
Project description:The transcription factor c-Myb has been well characterized as an oncogene in several human tumor types, and its expression in the hematopoietic stem/progenitor cell population is essential for proper hematopoiesis. However, the role of c-Myb in mammopoeisis and breast tumorigenesis is poorly understood, despite its high expression in the majority of breast cancer cases (60-80%). We find that c-Myb high expression in human breast tumors correlates with the luminal/ER+ phenotype and a good prognosis. RNAi knock-down of endogenous c-Myb levels in the MCF7 luminal breast tumor cell line increases tumorigenesis both in vitro and in vivo, suggesting a tumor suppressor role in luminal breast cancer. We created a mammary-derived c-Myb expression signature and found it to be highly correlated with a published mature luminal mammary cell signature and least correlated with a mammary stem/progenitor lineage gene signature. These data describe, for the first time, a tumor suppressor role for the c-Myb proto-oncogene in breast cancer that has implications for understanding luminal tumorigenesis and for guiding treatment. refXsample
2010-10-15 | E-GEOD-21371 | biostudies-arrayexpress
Project description:BACKGROUND: The transcription factor c-Myb has been well characterized as an oncogene in several human tumor types, and its expression in the hematopoietic stem/progenitor cell population is essential for proper hematopoiesis. However, the role of c-Myb in mammopoeisis and breast tumorigenesis is poorly understood, despite its high expression in the majority of breast cancer cases (60-80%). METHODOLOGY/PRINCIPAL FINDINGS: We find that c-Myb high expression in human breast tumors correlates with the luminal/ER+ phenotype and a good prognosis. Stable RNAi knock-down of endogenous c-Myb in the MCF7 luminal breast tumor cell line increased tumorigenesis both in vitro and in vivo, suggesting a possible tumor suppressor role in luminal breast cancer. We created a mammary-derived c-Myb expression signature, comprised of both direct and indirect c-Myb target genes, and found it to be highly correlated with a published mature luminal mammary cell signature and least correlated with a mammary stem/progenitor lineage gene signature. CONCLUSIONS/SIGNIFICANCE: These data describe, for the first time, a possible tumor suppressor role for the c-Myb proto-oncogene in breast cancer that has implications for the understanding of luminal tumorigenesis and for guiding treatment.
2010-10-15 | GSE21371 | GEO
Project description:Earlier we have shown important roles of MYB in pancreatic tumor pathobiology. To better understand the role of MYB in the tumor microenvironment and identify MYB-associated secreted biomarker proteins, we conducted mass spectrometry analysis of the secretome from MYB-modulated and control pancreatic cancer cell lines. We also performed in silico analyses to determine MYB-associated biofunctions, gene networks and altered biological pathways. We further investigated the secreted proteins for their potential biomarker properties.
2021-09-08 | PXD015126 | Pride
Project description:Most E2F-binding sites repress transcription through the recruitment of Retinoblasoma (RB) family members until the end of the G1 cell-cycle phase. Although the MYB promoter contains an E2F-binding site, its transcription is activated shortly after the exit from quiescence, before RB family members inactivation, by unknown mechanisms. We had previously uncovered a nuclear factor distinct from E2F, Myb-sp, whose DNA-binding site overlapped the E2F element and had hypothesized that this factor might overcome the transcriptional repression of MYB by E2F-RB family members. We have purified Myb-sp and discovered that Myc-associated zinc finger proteins (MAZ) are major components. We show that various MAZ isoforms are present in Myb-sp and activate transcription via the MYB-E2F element. Moreover, while forced RB or p130 expression repressed the activity of a luciferase reporter driven by the MYB-E2F element, co-expression of MAZ proteins not only reverted repression, but also activated transcription. Finally, we show that MAZ binds the MYB promoter in vivo, that its binding site is critical for MYB transactivation, and that MAZ knockdown inhibits MYB expression during the exit from quiescence. Together, these data indicate that MAZ is essential to bypass MYB promoter repression by RB family members and to induce MYB expression.
2017-10-04 | PXD006857 | Pride
Project description:The epithelium of the pulmonary airway is specially differentiated to provide defense against environmental insults, but also subject to dysregulated differentiation that results in lung disease. The current paradigm for airway epithelial differentiation is a one-step program whereby a p63+ basal epithelial progenitor cell generates a ciliated or secretory cell lineage, but the cue for this transition and whether there are intermediate steps is poorly defined. Here we identify transcription factor Myb as a key regulator that permits early multilineage differentiation of airway epithelial cells. Myb+ cells were identified as p63– and therefore distinct from basal progenitor cells, but were still negative for markers of differentiation. Myb RNAi treatment of primary-culture airway epithelial cells and Myb gene deletion in mice resulted in a p63– population with failed maturation of Foxj1+ ciliated cells, as well as Scbg1a1+ and Muc5ac+ secretory cells. Consistent with these findings, analysis of whole genome expression of Myb-deficient cells identified Myb-dependent programs for ciliated and secretory cell differentiation. Myb+ cells were rare in human airways but were increased in regions of ciliated cells and mucous cell hyperplasia in samples from subjects with chronic obstructive pulmonary disease. Together, the results show that a p63– Myb+ population of airway epithelial cells represents a distinct intermediate stage of differentiation that is required under normal conditions and may be heightened in airway disease.
2014-08-12 | GSE60365 | GEO
Project description:The epithelium of the pulmonary airway is specially differentiated to provide defense against environmental insults, but also subject to dysregulated differentiation that results in lung disease. The current paradigm for airway epithelial differentiation is a one-step program whereby a p63+ basal epithelial progenitor cell generates a ciliated or secretory cell lineage, but the cue for this transition and whether there are intermediate steps is poorly defined. Here we identify transcription factor Myb as a key regulator that permits early multilineage differentiation of airway epithelial cells. Myb+ cells were identified as p63– and therefore distinct from basal progenitor cells, but were still negative for markers of differentiation. Myb RNAi treatment of primary-culture airway epithelial cells and Myb gene deletion in mice resulted in a p63– population with failed maturation of Foxj1+ ciliated cells, as well as Scbg1a1+ and Muc5ac+ secretory cells. Consistent with these findings, analysis of whole genome expression of Myb-deficient cells identified Myb-dependent programs for ciliated and secretory cell differentiation. Myb+ cells were rare in human airways but were increased in regions of ciliated cells and mucous cell hyperplasia in samples from subjects with chronic obstructive pulmonary disease. Together, the results show that a p63– Myb+ population of airway epithelial cells represents a distinct intermediate stage of differentiation that is required under normal conditions and may be heightened in airway disease. 12 samples, 2x2 factorial design, factor 1: time (days post-ALI), factor 2:shRNA (Myb vs Scrambled Control), performed in triplicate (biological replicates)
2014-08-12 | E-GEOD-60365 | biostudies-arrayexpress
Project description:The B-myb (MYBL2) gene is a member of the MYB family of transcription factors and is involved in cell cycle regulation, DNA replication and maintenance of genomic integrity. However, its function during adult development and hematopoiesis is unknown. We show here that conditional inactivation of B-myb in vivo results in depletion of the HSC pool, leading to profound reductions in mature lymphoid, erythroid and myeloid cells. This defect is autonomous to the bone marrow and is first evident in the HSCs, which accumulate in the S and G2/M phases. B-myb inactivation also causes defects in the myeloid progenitor compartment and results in an accumulation of GMPs. Microarray studies indicate that B-myb null LKS+ cells differentially express genes that direct myeloid lineage development and commitment, suggesting that B-myb is a key player in controlling cell fate. Collectively, these studies demonstrate that B-myb is essential for HSC and progenitor maintenance and survival during hematopoiesis. Total RNA was isolated from FACS purified LKS+ cells isolated from pIpC-treated control and B-myb floxed-MxCre mice. Each sample is derived from a pool of 3-5 mice. 2 samples were analyzed for each genotype.
2014-02-12 | E-GEOD-53875 | biostudies-arrayexpress