The RNase III enzyme dicer is essential for the processing of microRNAs (miRNAs) and small interfering RNAs (siRNAs) from double-stranded RNA precursors. miRNAs and siRNAs regulate chromatin structure, gene transcription, mRNA stability and translation in a wide range of organisms. To provide a model system to explore the role of dicer-generated RNAs in the differentiation of mammalian cells in vivo, we have generated a conditional dicer allele. Deletion of dicer at an early stage of T cell development compromised the survival of lineage cells, while the numbers of -expressing thymocytes were not affected. In developing thymocytes, dicer was not required for the maintenance of transcriptional silencing at pericentromeric satellite sequences (constitutive heterochromatin), the maintenance of cytosine DNA methylation and X chromosome inactivation in female cells (facultative heterochromatin) and the stable shutdown of a developmentally regulated gene (developmentally regulated gene silencing). Most remarkably, given that one-third of mammalian mRNAs are putative miRNA targets, dicer appears to be dispensable for CD4/8 lineage commitment, a process where epigenetic regulation of lineage choice has been well documented. Thus, although dicer appears critical for the development of the early embryo, it may have limited impact on the implementation of lineage-specific gene expression programs.
microRNAs regulate cell-to-cell variability of endogenous target gene expression in developing mouse thymocytes.
Specimen part
View SamplesmiRNA regulate gene expression at the post-transcriptionnal level. To gain further insight into this process, we analysed by Affymetrix microarray, the transcriptome of Dicer WT or Dicer deleted mouse CD4 T cells.
microRNA-mediated regulation of mTOR complex components facilitates discrimination between activation and anergy in CD4 T cells.
Specimen part
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MicroRNAs of the miR-290-295 Family Maintain Bivalency in Mouse Embryonic Stem Cells.
Specimen part
View SamplesThe protein Dicer is required for microRNA (miRNA) biogenesis. Dicer-deficient cells therefore lack almost all mature, functional miRNAs. We investigated the role of miRNAs in regulation of gene expression in mouse
MicroRNAs of the miR-290-295 Family Maintain Bivalency in Mouse Embryonic Stem Cells.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Post-transplant molecularly defined Burkitt lymphomas are frequently MYC-negative and characterized by the 11q-gain/loss pattern.
Sex, Age, Treatment
View SamplesWe performed genomic and transcriptomic analysis of seven cases of molecular Burkitt lymphoma (mBL) developed in immunosuppressed patients who underwent solid organ transplantation. Interestingly, three cases (43%) were MYC-translocation-negative and revealed the 11q-gain/loss aberration recently identified in 3% of mBL developed in immunocompetent hosts.1 Based on array CGH data, minimal gain and loss regions of 11q (MGR/~4Mb and MLR/~13.5Mb, respectively) were defined and integrative genomic and transcriptomic analysis identified 35 differentially expressed genes, when compared with classic BL. All 16 MGR-dysregulated genes were upregulated, including cancer related USP2, CBL and PAFAH1B2. As expected, all 19 MGL-dysregulated genes were downregulated and two of them, TBRG1 and EI24, are potential tumor suppressor genes. Interestingly, the vast majority of dysregulated 11q23-q25 genes are involved in the MYC and TP53 networks. We hypothesize that the 11q-gain/loss aberration represents a molecular variant of t(8q24/MYC) and affects the same pathological pathways as the MYC oncogene.
Post-transplant molecularly defined Burkitt lymphomas are frequently MYC-negative and characterized by the 11q-gain/loss pattern.
Sex, Age, Treatment
View SamplesTransient expression of two factors, or from Oct4 alone, resulted in efficient generation of human iPSCs. The reprogramming strategy described revealed a potential transcriptional signature for human iPSCs yet retaining the gene expression of donor cells in human reprogrammed cells free of viral and transgene interference.
Transcriptional signature and memory retention of human-induced pluripotent stem cells.
Sex, Specimen part
View SamplesA rare complication of multiple myeloma is a secondary extramedullary involvement, and the skin is one of the possible sites, due to the physiological homing of plasma cells (PCs) into the skin. The article reports a case of a relapsed refractory MM patient, who developed a cutaneous localization after 16 months from the diagnosis under Bortezomib treatment without a leukemic phase. Patient was refractory to Bortezomib. We analyzed the gene expression profiles, the immunophenotypic and immunohistochemistry profiles of MM cells across the course of the disease at the bone marrow and skin localization. Data obtained were further expanded by an immunohistochemistry analysis on selected molecules in a large cohort of MM patients with cutaneous localization. In particular we focused on the expression of chemokines and chemokine receptors involved in the PC skin homing.
Cutaneous localization in multiple myeloma in the context of bortezomib-based treatment: how do myeloma cells escape from the bone marrow to the skin?
Sex, Age, Specimen part, Subject, Time
View SamplesThe biological effects of TTR proteins in the vasculature remain unknown.
Transthyretin proteins regulate angiogenesis by conferring different molecular identities to endothelial cells.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Profiling of the transcriptional response to all-trans retinoic acid in breast cancer cells reveals RARE-independent mechanisms of gene expression.
Cell line
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