The first week of human pre-embryo development is characterized by the induction of totipotency and then pluripotency. The understanding of this delicate process will have far reaching implication for in vitro fertilization and regenerative medicine. Human mature MII oocytes and embryonic stem (ES) cells are both able to achieve the feat of cell reprogramming towards pluripotency, either by somatic cell nuclear transfer or by cell fusion, respectively. Comparison of the transcriptome of these two cell types may highlight genes that are involved in pluripotency initiation. Therefore, based on a microarray compendium of 205 samples, produced in our laboratory or from public databases, we compared the gene expression profile of mature MII oocytes and human ES cells (hESC) to that of somatic tissues. We identified a common oocyte/hESC gene expression profile, which included a strong cell cycle signature, a large chromatin remodelling network (TOP2A, DNMT3B, JARID2, SMARCA5, CBX1, CBX5) and 18 different zinc finger transcription factors, including ZNF84. Strikingly, a large set of genes was found to code for proteins involved in the ubiquitination and proteasome pathway. Upon hESC differentiation into embryoid bodies, the transcription of this pathway declines. In vitro, we observed a selective sensitivity of hESC to the inhibition of the activity of the proteasome, resulting in loss of pluripotency and cell growth at doses without any detectable effects on differentiated cells. Taken together, these results suggest that the proteasome pathway may play a role in initiating and maintaining pluripotency during early development and in hESC.
A gene expression signature shared by human mature oocytes and embryonic stem cells.
No sample metadata fields
View SamplesPluripotent stem cells, which are capable to generate any cell type of the human body, such as human embryonic stem cells (hESC) or human induced pluripotent stem cells (hiPS) are a very promising source of cells for regenerative medicine. However, the genesis, the in vitro amplification and the differentiation of these cells still need improvement before clinical use. This study aimed to improve our knowledge on these critical steps in pluripotent stem cell generation. We derived new hESC lines, generated hiPS and compared these cell types with human foreskin fibroblasts and partially reprogrammed fibroblasts.
A gene expression signature shared by human mature oocytes and embryonic stem cells.
Specimen part, Cell line
View SamplesRecent advances in high density oligonucleotides microarray technology have brought solutions for molecular profiling of human samples at an unprecedented resolution. We mapped whole blood RNA from healthy volunteers and CD34+ from cytapheresis to Human Exon ST 1.0 microarrays. We compared mature blood cells samples with immature CD34+ samples and each of these compartiement with a broad panel of solid tissues. By scanning the expression of over one million known or predicted exons, transcripts such as INPP4B, NEDD9 CD74 and VAV3 were identified as alternatively transcribed between haematopoietic system and solid tissues. The very large combinatorial complexity conveyed by alternative splicing contributes to the specific functional properties of blood cells and haematopoietic stem cells. The gene expression profiles are freely accessible through a dynamic web atlas, providing to the medical and scientific community a simple mean to interrogate and visualize this reference dataset. Finally, the relevance and the precision provided by this exon expression map suggest that exon arrays may be a powerful tool to link specific peripheral whole blood exon signatures modifications to many diseases such as cancer or auto-immune disorders.
Expression map of the human exome in CD34+ cells and blood cells: increased alternative splicing in cell motility and immune response genes.
Specimen part
View SamplesAnalysis of MCF-7 cells treated for 4h with Ethanol, Estradiol (E2), Dexamethasone (Dex), or Estradiol + Dexamethasone (E2 + Dex)
GR and ER Coactivation Alters the Expression of Differentiation Genes and Associates with Improved ER+ Breast Cancer Outcome.
Cell line
View SamplesThis study was performed to test the hypothesis that cigarette smoke extract would alter the responses of primary cultures of human bronchial epithelial cells to infection with purified human rhinovirus 16.
Cigarette smoke modulates expression of human rhinovirus-induced airway epithelial host defense genes.
Specimen part, Subject
View SamplesTo identify candidate genes involved in enhanced tumorigenicity and metastasis of CD90+ esophageal tumor-initiating cells.
A CD90(+) tumor-initiating cell population with an aggressive signature and metastatic capacity in esophageal cancer.
Specimen part, Cell line
View SamplesThe tumor suppressor p53 is a transcription factor that coordinates the cellular response to DNA damage. Here we provide an integrated analysis of p53 genomic occupancy and p53-dependent gene regulation in the splenic B and non-B cell compartments of mice exposed to whole-body ionizing radiation, providing insight into general principles of p53 activity in vivo. In unstressed conditions, p53 bound few genomic targets; induction of p53 by ionizing radiation increased the number of p53 bound sites, leading to highly overlapping profiles in the different cell types. Comparison of these profiles with chromatin features in unstressed B cells revealed that, upon activation, p53 localized at active promoters, distal enhancers, and a smaller set of unmarked distal regions. At promoters, recognition of the canonical p53 motif as well as binding strength were associated with p53-dependent transcriptional activation, but not repression, indicating that the latter was most likely indirect. p53-activated targets constituted the core of a cell type-independent response, superimposed onto a cell type-specific program. Core response genes included most of the known p53-regulated genes, as well as many new ones. Our data represent a unique characterization of the p53-regulated response to ionizing radiation in vivo. Overall design: Total RNA profiling of gene expression in the splenic B and non-B cell compartments of wild-type and Trp53-/-mice exposed to whole-body ionizing radiation by Illumina sequencing
p53 transcriptional programs in B cells upon exposure to genotoxic stress in vivo: Computational analysis of next-generation sequencing data.
No sample metadata fields
View SamplesTranscriptomic studies revealed that hundreds of mRNAs show differential expression in the brains of sleeping versus awake rats, mice, flies, and sparrows. Although these results have offered clues regarding the molecular consequences of sleep and sleep loss, their functional significance thus far has been limited. This is because the previous studies pooled transcripts from all brain cells, including neurons and glia.
Transcriptome profiling of sleeping, waking, and sleep deprived adult heterozygous Aldh1L1 - eGFP-L10a mice.
Disease
View SamplesActivity-dependent transcriptional profiling was performed in the basolateral amygdala in order to identify unique genetic markers for functionally distinct neuronal populations
Antagonistic negative and positive neurons of the basolateral amygdala.
No sample metadata fields
View SamplesUsing a CML mouse model, we identified differences in gene expression between leukemic compared with non-leukemic LTHSC, including increased expression of the thrombopoietin (THPO) receptor MPL. LTHSC expressing high levels of MPL showed enhanced JAK/STAT signaling and proliferation in response to THPO in vitro, and increased leukemogenic capacity in vivo compared to LTHSC with low MPL expression. Although both G0 and S-phase subpopulations were increased in MPL expressing LTHSC, LSC capacity was restricted to quiescent cells. Inhibition of MPL expression in CML LTHSC resulted in reduced THPO-induced JAK/STAT signaling and leukemogenic potential. Similar observations were made with LTHSC from CML patients. MPL expressing LTHSC demonstrated reduced sensitivity to BCR-ABL TKI treatment but demonstrated increased sensitivity to JAK inhibitors. Our studies identify MPL expression levels as a key determinant of heterogeneous leukemia-initiating capacity and drug sensitivity of CML LTHSC, and suggest that MPL-expressing CML stem cells are critical targets for therapy. Overall design: To evaluate heterogeneity in LSC potential, donor LTHSC from SCL-tTA/BCR-ABL mice (200 cells/mouse) were transplanted into a cohort of congenic FVBN mice. Recipient mice were followed for engraftment of donor CML cells and development of CML. LTHSCs were isolated from leukemic and non-leukemic recipient mice and global gene expression was analyzed using RNA-Seq.
Heterogeneity of leukemia-initiating capacity of chronic myelogenous leukemia stem cells.
Specimen part, Subject
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