p53 induces cell death upon DNA damage, but this may not confer all of its tumor suppressor activity. We report that p53 activation enhances the processivity of DNA replication, as monitored by multi-label fiber assays, whereas removal of p53 reduces fork progression. This was observed in tumor-derived U2OS cells, but also in murine embryonic fibroblasts with heterozygous or homozygous p53 deletion, and in freshly isolated thymocytes from mice with differential p53 status. Mdm2, a p53-inducible gene product, similarly supported DNA replication even in p53-deficient cells, suggesting that sustained Mdm2-expression is at least one of the mechanisms allowing p53 to prevent replicative stress. Thus, p53 helps to protect the genome during S phase, by preventing the occurrence of stalled or collapsed replication forks. These results expand p53’s tumor-suppressive functions, adding to the ex-post model (elimination of damaged cells) an ex-ante activity, i.e. the prevention of DNA damage during replication. Overall design: Expression profiling by high throughput sequencing
p53 Activity Results in DNA Replication Fork Processivity.
Specimen part, Cell line, Subject
View SamplesMouse erythroid progenitors (EP) in comparison to granulocyte/monocyte - macrophage progenitors (GMP) from 10 - 16 week old C57/Bl6 - S129Ola (mixed genetic background) purified by flow cytometry
Prospective isolation and global gene expression analysis of the erythrocyte colony-forming unit (CFU-E).
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Cell competition is a tumour suppressor mechanism in the thymus.
Specimen part
View SamplesLeukemia cells are considered developmentally 'frozen', and their phenotype is thought to reflect their stage of origin. To gain insights into the cell population from which T-ALL arises, we compared by global gene expression profiling T-ALL samples (n = 10) to different stages of T cell development, following the order from early thymic progenitor (ETP), to triple negative (TN) TN2, to TN3, to TN4, to immature single positive (ISP), to double positive (DP) thymocytes.
Cell competition is a tumour suppressor mechanism in the thymus.
Specimen part
View SamplesWild type thymi were transplanted into a competitive (wild type hosts), or non-competitive (Rag2-/-c-/-KitW/Wv hosts) environment. Triple negative 2 and 3 (TN2/3) stages were sorted 14 days afetr transplantation and separated for cells of host or donor origin.
Cell competition is a tumour suppressor mechanism in the thymus.
Specimen part
View SamplesTranscriptome was assessed in the transitions from the normal thymus (with regular progenitor turnover), to a thymus devoid of extrinsic progenitor competition for 10 weeks, to fully malignant T cell acute lymphoblastic leukemia (T-ALL).
Cell competition is a tumour suppressor mechanism in the thymus.
Specimen part
View SamplesIt is now well established that the E- and Id-protein axis regulates multiple steps in lymphocyte development. However, it remains unknown as to how E- and Id-proteins mechanistically enforce and maintain the naïve T cell fate. Here we show that Id2 and Id3 suppressed the development and expansion of innate-variant TFH cells. Innate-variant TFH cells required MHC Class I-like signalling and were associated with germinal center B cell development. We found that Id2 and Id3 induced Foxo1 and Foxp1 expression to antagonize the activation of TFH transcription signature. We show that Id2 and Id3 acted upstream of the Hif1a/Foxo/AKT/mTORC1 pathway as well as the c-myc/p19Arf module to control cellular expansion and activation. We found that mice depleted for Id2 and Id3 expression developed colitis and aß T cell lymphomas. Lymphomas depleted for Id2 and Id3 expression displayed elevated levels of c-myc whereas p19Arf abundance declined. Transcription signatures of Id2- and Id3-depleted lymphomas revealed similarities with genetic deficiencies associated with Burkitt lymphoma. We propose that in response to antigen receptor and/or cytokine signaling the E-Id protein axis modulates the activities of the PI3K-AKT-mTORC1-Hifa and c-myc/p19Arf pathways to control cellular expansion and homeostatic proliferation. Overall design: RNA-seq data of 5 of wild type CD4SP cells, 3 of wild type Tfh cells, 3 of Id3-/- CD4SP cells, 3 of Id2-/-Id3-/-(dKO) CD4SP cells, and 6 of Id2-/-Id3-/- lymphoma cells.
The E-Id protein axis modulates the activities of the PI3K-AKT-mTORC1-Hif1a and c-myc/p19Arf pathways to suppress innate variant TFH cell development, thymocyte expansion, and lymphomagenesis.
No sample metadata fields
View SamplesRNA sequencing of ILC2s sorted from ß2 adrenergic receptor agonist-treated and non-treated mice Overall design: RNAs of ILC2s sorted as KLRG1+CD127+CD90+Lin-CD45+ from ß2 adrenergic receptor agonist-treated and non-treated mice mLNs 4 days post N. brasiliensis infection were analyzed
β<sub>2</sub>-adrenergic receptor-mediated negative regulation of group 2 innate lymphoid cell responses.
Specimen part, Cell line, Treatment, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
GATA4-dependent organ-specific endothelial differentiation controls liver development and embryonic hematopoiesis.
Specimen part, Cell line
View SamplesMicrovascular endothelial cells (EC) are increasingly recognized as organ-specific gatekeepers of their microenvironment. Microvascular EC instruct neighboring cells in their organ-specific vascular niches by angiocrine factors that comprise secreted growth factors/angiokines, but also extracellular matrix molecules and transmembrane proteins. The molecular regulators, however, that drive organ-specific microvascular transcriptional programs and thereby regulate angiodiversity, are largely elusive. Opposite to continuous barrier-forming EC, liver sinusoids are a prime model of discontinuous, permeable micro-vessels. Here, we show that transcription factor GATA4 controls liver sinusoidal endothelial (LSEC) specification and function. LSEC-restricted deletion of GATA4 caused transformation of discontinuous liver sinusoids into continuous capillaries. Capillarization was characterized by ectopic basement membrane deposition and formation of an abundantly VE-Cadherin expressing continuous endothelium. Correspondingly, ectopic expression of GATA4 in cultured continuous EC mediated downregulation of continuous EC transcripts and upregulation of LSEC genes. Regarding angiocrine functions, the switch from discontinuous LSEC to continuous EC during embryogenesis caused liver hypoplasia, fibrosis, and impaired colonization by hematopoietic progenitor cells resulting in anemia and embryonic lethality. Thus, GATA4 acts as master regulator of hepatic microvascular specification and acquisition of organ-specific vascular competence indispensable for liver development. The data also establish an essential role of the hepatic microvasculature for embryonic hematopoiesis.
GATA4-dependent organ-specific endothelial differentiation controls liver development and embryonic hematopoiesis.
Cell line
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