| 1. |
- C. Lin, Yin, et al.
(författare)
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A global network of transcription factors, involving E2A, EBF1 and Foxo1, that orchestrates B cell fate
- 2010
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Ingår i: Nature Immunology. - : Nature Publishing Group. - 1529-2908 .- 1529-2916. ; 11:7, s. 635-U109
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Tidskriftsartikel (refereegranskat)abstract
- It is now established that the transcription factors E2A, EBF1 and Foxo1 have critical roles in B cell development. Here we show that E2A and EBF1 bound regulatory elements present in the Foxo1 locus. E2A and EBF1, as well as E2A and Foxo1, in turn, were wired together by a vast spectrum of cis-regulatory sequences. These associations were dynamic during developmental progression. Occupancy by the E2A isoform E47 directly resulted in greater abundance, as well as a pattern of monomethylation of histone H3 at lysine 4 (H3K4) across putative enhancer regions. Finally, we divided the pro-B cell epigenome into clusters of loci with occupancy by E2A, EBF and Foxo1. From this analysis we constructed a global network consisting of transcriptional regulators, signaling and survival factors that we propose orchestrates B cell fate.
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| 2. |
- Mansson, Robert, et al.
(författare)
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Positive intergenic feedback circuitry, involving EBF1 and FOXO1, orchestrates B-cell fate
- 2012
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 109:51, s. 21028-21033
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies have identified a number of transcriptional regulators, including E2A, early B-cell factor 1 (EBF1), FOXO1, and paired box gene 5 (PAX5), that promote early B-cell development. However, how this ensemble of regulators mechanistically promotes B-cell fate remains poorly understood. Here we demonstrate that B-cell development in FOXO1-deficient mice is arrested in the common lymphoid progenitor (CLP) LY6D(+) cell stage. We demonstrate that this phenotype closely resembles the arrest in B-cell development observed in EBF1-deficient mice. Consistent with these observations, we find that the transcription signatures of FOXO1- and EBF1-deficient LY6D(+) progenitors are strikingly similar, indicating a common set of target genes. Furthermore, we found that depletion of EBF1 expression in LY6D(+) CLPs severely affects FOXO1 mRNA abundance, whereas depletion of FOXO1 activity in LY6D(+) CLPs ablates EBF1 transcript levels. We generated a global regulatory network from EBF1 and FOXO1 genome-wide transcription factor occupancy and transcription signatures derived from EBF1- and FOXO1-deficient CLPs. This analysis reveals that EBF1 and FOXO1 act in a positive feedback circuitry to promote and stabilize specification to the B-cell lineage.
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| 3. |
- Mercer, Elinore M, et al.
(författare)
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Multilineage Priming of Enhancer Repertoires Precedes Commitment to the B and Myeloid Cell Lineages in Hematopoietic Progenitors
- 2011
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Ingår i: Immunity. - : Elsevier (Cell Press). - 1074-7613 .- 1097-4180. ; 35:3, s. 413-425
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies have documented genome-wide binding patterns of transcriptional regulators and their associated epigenetic marks in hematopoietic cell lineages. In order to determine how epigenetic marks are established and maintained during developmental progression, we have generated long-term cultures of hematopoietic progenitors by enforcing the expression of the E-protein antagonist Id2. Hematopoietic progenitors that express Id2 are multipotent and readily differentiate upon withdrawal of Id2 expression into committed B lineage cells, thus indicating a causative role for E2A (Tcf3) in promoting the B cell fate. Genome-wide analyses revealed that a substantial fraction of lymphoid and myeloid enhancers are premarked by the poised or active enhancer mark H3K4me1 in multipotent progenitors. Thus, in hematopoietic progenitors, multilineage priming of enhancer elements precedes commitment to the lymphoid or myeloid cell lineages.
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| 4. |
- Welinder, Eva, et al.
(författare)
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The transcription factors E2A and HEB act in concert to induce the expression of FOXO1 in the common lymphoid progenitor
- 2011
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 108:42, s. 17402-17407
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies have identified a number of transcriptional regulators, including E proteins, EBF1, FOXO1, and PAX5, that act together to orchestrate the B-cell fate. However, it still remains unclear as to how they are linked at the earliest stages of B-cell development. Here, we show that lymphocyte development in HEB-ablated mice exhibits a partial developmental arrest, whereas B-cell development in E2A(+/-)HEB(-/)-mice is completely blocked at the LY6D(-) common lymphoid progenitor stage. We show that the transcription signatures of E2A-and HEB-ablated common lymphoid progenitors significantly overlap. Notably, we found that Foxo1 expression was substantially reduced in the LY6D-HEB-and E2A-deficient cells. Finally, we show that E2A binds to enhancer elements across the FOXO1 locus to activate Foxo1 expression, linking E2A and FOXO1 directly in a common pathway. In summary, the data indicate that the earliest event in B-cell specification involves the induction of FOXO1 expression and requires the combined activities of E2A and HEB.
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