This SuperSeries is composed of the SubSeries listed below.
HoxA3 is an apical regulator of haemogenic endothelium.
Specimen part
View SamplesWe used a murine ES cell line in which HoxA3 expression is under control of a tetracycline-responsive element and differentiated these cells as embryoid bodies (EBs). Endothelial (Flk-1 VE-cadherin double positive, FV) and hematopoieitc progenitors (c-Kit CD41 double positive, K41) were isolated from differentiated EBs that had been induced for 6 hours by doxycycline (Dox) treatment.
HoxA3 is an apical regulator of haemogenic endothelium.
Specimen part
View SamplesThe Hippo pathway directs cell differentiation during organogenesis, in part by restricting proliferation. How Hippo signaling maintains a proliferation-differentiation balance in developing tissues and its underlying molecular targets are poorly understood. Our study shows that Hippo suppresses NF?B signaling in pancreatic progenitors to permit cell differentiation and developmental progression. We found that pancreas-specific Lats1/2 kinase deletion (Lats1/2PanKO) from mouse progenitor epithelia results in failure to differentiate 3 key pancreatic lineages: acinar, ductal, and endocrine. We performed an unbiased transcriptome analysis to query the differentiation defects in Lats1/2PanKO. This analysis revealed increased NF?B activator expression, including the pantetheinase Vanin1 (Vnn1). Through in vivo and ex vivo studies, we show that VNN1 activates a detrimental cascade of processes in Lats1/2PanKO epithelium, whereby 1) NF?B activation and 2) initiation of epithelial-to-mesenchymal transition (EMT) together override normal differentiation. We show that exogenous stimulation of VNN1 or NF?B can also trigger this cascade in WT pancreatic progenitors. These findings show that pancreas development requires active suppression of NF?B by LATS1/2 kinases to restrain a cell-autonomous transcriptional program and thereby allow for differentiation. Overall design: RNA-Seq comparing total RNA from 5 WT samples and 3 Lats1/2-deficient pancreas samples at E11.0.
LATS1/2 suppress NFκB and aberrant EMT initiation to permit pancreatic progenitor differentiation.
Cell line, Subject
View SamplesThis study examined the effects of genetic knockdown of autophagy genes on vertebrate cardiac development
Autophagy is essential for cardiac morphogenesis during vertebrate development.
Age, Specimen part
View SamplesHow organ size and form are controlled during development is a major question of biology. Blood vessels have been shown to be essential for early development of the liver and pancreas, and are fundamental to normal and pathological tissue growth. Here we report that non-nutritional signals from blood vessels surprisingly act to restrain pancreas growth. Elimination of endothelial cells increases the size of embryonic pancreatic buds. Conversely, VEGF-induced hypervascularization decreases pancreas size. The growth phenotype results from vascular restriction of pancreatic tip cell formation, lateral branching and differentiation of the pancreatic epithelium into endocrine and acinar cells. The effects are seen both in vivo and ex vivo, indicating a perfusion-independent mechanism. Thus the vasculature controls pancreas morphogenesis and growth by reducing branching and differentiation of primitive epithelial cells.
Blood vessels restrain pancreas branching, differentiation and growth.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Pbx1 regulates self-renewal of long-term hematopoietic stem cells by maintaining their quiescence.
Age, Specimen part
View SamplesSelf-renewal is a defining characteristic of stem cells, however the molecular pathways underlying its regulation are poorly understood. Here we demonstrate that conditional inactivation of the Pbx1 proto-oncogene in the hematopoietic compartment results in a progressive loss of long-term hematopoietic stem cells (LT-HSCs) that is associated with concomitant reduction in their quiescence, leading to a defect in the maintenance of self-renewal as assessed by serial transplantation. Transcriptional profiling revealed that multiple stem cell maintenance factors are perturbed in Pbx1-deficient LT-HSCs, which prematurely express a large subset of genes, including cell cycle regulators, normally expressed in non-self-renewing multipotent progenitors. A significant proportion of Pbx1-dependent genes are associated with the Tgf-b pathway, which serves a major role in maintaining HSC quiescence. Pbx1-deficient LT-HSCs are unable to up-regulate the cyclin dependent kinase inhibitor p57 in response to Tgf-b, providing a mechanism through which Pbx1 maintenance of stem cell self-renewal is achieved.
Pbx1 regulates self-renewal of long-term hematopoietic stem cells by maintaining their quiescence.
Age, Specimen part
View SamplesSelf-renewal is a defining characteristic of stem cells, however the molecular pathways underlying its regulation are poorly understood. Here we demonstrate that conditional inactivation of the Pbx1 proto-oncogene in the hematopoietic compartment results in a progressive loss of long-term hematopoietic stem cells (LT-HSCs) that is associated with concomitant reduction in their quiescence, leading to a defect in the maintenance of self-renewal as assessed by serial transplantation. Transcriptional profiling revealed that multiple stem cell maintenance factors are perturbed in Pbx1-deficient LT-HSCs, which prematurely express a large subset of genes, including cell cycle regulators, normally expressed in non-self-renewing multipotent progenitors.
Pbx1 regulates self-renewal of long-term hematopoietic stem cells by maintaining their quiescence.
Age, Specimen part
View SamplesThere are currently no biological tests that differentiate patients with bipolar disorder (BPD) from healthy controls. While there is evidence that peripheral gene expression differences between patients and controls can be utilized as biomarkers for psychiatric illness, it is unclear whether current use or residual effects of antipsychotic and mood stabilizer medication drives much of the differential transcription. We therefore tested whether expression changes in first-episode, never-medicated bipolar patients, can contribute to a biological classifier that is less influenced by medication and could potentially form a practicable biomarker assay for BPD.
Utilization of never-medicated bipolar disorder patients towards development and validation of a peripheral biomarker profile.
Sex, Age, Specimen part
View SamplesIrritant contact dermatitis (ICD) pathogenesis is not completely understood and the genes participating in the epidermal response towards chemical irritants are only partly known. It is commonly accepted that different irritants have different mechanisms of action in the development of ICD. To define the differential molecular events induced in the epidermis by different irritants, we collected sequential biopsies (, 4 and 24 hours after a single exposure and at day 11 after repeated exposure) from human volunteers exposed to sodium lauryl sulphate (SLS) or nonanoic acid (NON). Gene expression analysis using high-density oligonucleotide microarrays revealed essentially different pathway responses h after exposure: NON transiently induced the IL-6 pathway as well as a number of mitogen activated signalling cascades including ERK and growth factor receptor signalling, whereas SLS transiently downregulated cellular energy metabolism pathways. Differential expression of the cyclooxygenase-2 and matrix metalloproteinase 3 transcripts was confirmed immunohistochemically. After cumulative exposure, 883 genes were differentially expressed while 26 suggested common biomarkers were identified . In conclusion, we bring new insights into two hitherto less well elucidated phases of skin irritancy: the very initial as well as the late phase after single and cumulative exposure, respectively.
Genome-wide expression analysis of human in vivo irritated epidermis: differential profiles induced by sodium lauryl sulfate and nonanoic acid.
Specimen part
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