We report that developmental competition between sympathetic neurons for survival is critically dependent on a sensitization process initiated by target innervation and mediated by a series of feedback loops. Target-derived nerve growth factor (NGF) promoted expression of its receptor TrkA in neurons and prolonged TrkA-mediated signals. NGF also controlled expression of brain derived neurotrophic factor (BDNF) and neurotrophin-4 (NT4), which, through the receptor p75, can kill neighboring neurons with low retrograde NGFTrkA signaling whereas neurons with high NGFTrkA signaling are protected. Perturbation of any of these feedback loops disrupts the dynamics of competition. We suggest that three target-initiated events are essential for rapid and robust competition between neurons: sensitization, paracrine apoptotic signaling, and protection from such effects.
A model for neuronal competition during development.
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View SamplesAdam10, a cell surface protease, cleaving many proteins including TNF-alpha and E-cadherin. Here we investigate the genome wide effects of Adam10 knock out on the transcriptome.
The disintegrin/metalloproteinase Adam10 is essential for epidermal integrity and Notch-mediated signaling.
Specimen part
View SamplesCD20 is a clinically validated target for Non-Hodgkins lymphomas and autoimmune diseases. Interactions of CD20 with the B cell receptor (BCR) and components of the BCR signaling cascade have been reported. In this study we show that antibodies against CD20 or activation of the BCR by specific antibodies induce very similar expression patterns of up- or down-regulated genes in NHL cell lines indicating that CD20 may play a role in BCR signaling and vice versa.
Antibodies against CD20 or B-cell receptor induce similar transcription patterns in human lymphoma cell lines.
Cell line, Treatment
View SamplesBackground: Several genetic defects of the nucleotide excision repair (NER) pathway, including deficiency of the Excision Repair Cross-Complementing rodent repair deficiency, complementation group 1 (ERCC1), result in pre-mature aging, impaired growth, microcephaly and delayed development of the cerebellum. Such a phenotype also occurs in ERCC1-knockout mice which survive for up to 4 weeks after birth. Therefore, we analyzed cerebellar and hippocamapal transcriptomes of these animals at 3 weeks of age to identify the candidate mechanisms underlying brain consequences of reduced ERCC1 activity.
Downregulation of cholesterol biosynthesis genes in the forebrain of ERCC1-deficient mice.
No sample metadata fields
View SamplesTranscriptomes of mesenchymal stromal cells from bone marrow (bmMSC) were compared to MSC from term placenta (pMSC).
Expression of Desmoglein 2, Desmocollin 3 and Plakophilin 2 in Placenta and Bone Marrow-Derived Mesenchymal Stromal Cells.
Specimen part
View SamplesThese samples were all taken from patients who underwent investigations including colonoscopy but where all tests were normal and the diagnosis of irritable bowel syndrome was reached. These observations have been used as references in studies of colonic gene expression in inflammatory bowel diseases
Clinical phenotype and gene expression profile in Crohn's disease.
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View SamplesEpilepsy is a common cause of morbidity affecting approximately one third of patients with primary brain tumors. However, the molecular mechanism underlying the tumor induced epileptogenesis is poorly understood. The alteration in peritumoral microenvironments is believed to play a significant role in inducing epileptogenesis.
Transcriptomic profiling of human peritumoral neocortex tissues revealed genes possibly involved in tumor-induced epilepsy.
Sex, Specimen part, Disease, Disease stage
View SamplesGestational protein restriction is a model for low birth size. We hypothesized that taurine supplementation would protect against changes in newborn liver and muscle caused by a maternal low protein diet.
Gestational protein restriction in mice has pronounced effects on gene expression in newborn offspring's liver and skeletal muscle; protective effect of taurine.
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View SamplesRetinoic acid (RA), an active derivative of the liposoluble vitamin A (retinol), acts as an important signaling molecule during embryonic development, regulating phenomenons as diverse as anterior-posterior axial patterning, forebrain and optic vesicle development, specification of hindbrain rhombomeres, pharyngeal arches and second heart field, somitogenesis, and differentiation of spinal cord neurons. This small molecule directly triggers gene activation by binding to nuclear receptors (RARs), switching them from potential repressors to transcriptional activators. The repertoire of RA-regulated genes in embryonic tissues is poorly characterized. We performed a comparative analysis of the transcriptomes of murine wild-type and Retinaldehyde Dehydrogenase 2 null-mutant (Raldh2-/-) embryos - unable to synthesize RA from maternally-derived retinol - using Affymetrix DNA microarrays. Transcriptomic changes were analyzed in two embryonic regions: anterior tissues including forebrain and optic vesicle, and posterior (trunk) tissues, at early stages preceding the appearance of overt phenotypic abnormalities. Several genes expected to be downregulated under RA deficiency appeared in the transcriptome data (e.g. Emx2, Foxg1 anteriorly, Cdx1, Hoxa1, Rarb posteriorly), whereas reverse-transcriptase-PCR and in situ hybridization performed for additional selected genes validated the changes identified through microarray analysis. Altogether, the affected genes belonged to numerous molecular pathways and cellular/organismal functions, demonstrating the pleiotropic nature of RA-dependent events. In both tissue samples, genes upregulated were more numerous than those downregulated, probably due to feedback regulatory loops. Bioinformatic clustering analysis allowed us to extract groups of genes displaying similar behaviors in mutant tissue samples. These data give an overview of the gene expression changes occurring under a state of embryonic RA deficiency, and provide new candidate genes and pathways for a better understanding of retinoid-dependent molecular events.
Transcriptomic analysis of murine embryos lacking endogenous retinoic acid signaling.
Specimen part
View SamplesAnalysis of newborn mouse epidermis lacking the expression of Insulin receptor (IR) and Insulin like growth factor 1 receptor (IGF-1R). Results show that IR/IGF-1R signalling control epidermal morphogenesis.
Insulin/IGF-1 controls epidermal morphogenesis via regulation of FoxO-mediated p63 inhibition.
No sample metadata fields
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