MicroRNAs (miRNA) are small, non-coding RNAs mediating post-transcriptional regulation of gene expression. miRNAs have recently been implicated in hippocampus-dependent functions such as learning and memory, although the roles of individual miRNAs in these processes remain largely unknown. Here, we achieved stable inhibition using AAV-delivered miRNA sponges of individual, highly expressed and brain-enriched miRNAs; miR-124, miR-9 and miR-34, in hippocampal neurons. Molecular and cognitive studies revealed a role for miR-124 in learning and memory. Inhibition of miR-124 resulted in an enhanced spatial learning and working memory capacity, potentially through altered levels of genes linked to synaptic plasticity and neuronal transmission. In contrast, inhibition of miR-9 or miR-34 led to a decreased capacity of spatial learning and of reference memory, respectively. On a molecular level, miR-9 inhibition resulted in altered expression of genes related to cell adhesion, endocytosis and cell death, while miR-34 inhibition caused transcriptome changes linked to neuroactive ligand-receptor transduction and cell communication. In summary, this study establishes distinct roles for individual miRNAs in hippocampal function. Overall design: Three RNA samples containing bilateral entire hippocampi from three different mice, per group. Group 1 were injected with vector containing GFP and a miR34sp/miR9sp and the other group were subjected to a vector expressing GFP only.
Distinct cognitive effects and underlying transcriptome changes upon inhibition of individual miRNAs in hippocampal neurons.
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View SamplesWe established a neuron-specific Argonaute2:GFP-RNA immunoprecipitation followed by high throughput sequencing (AGO2-RIP-seq) to analyse the regulatory role of miRNAs in mouse hippocampal neurons. Using this technique, we identified more than two thousand miRNA target genes in hippocampal neurons, regulating essential neuronal features such as axon guidance and transcription. Furthermore, we found that stable inhibition of the highly expressed miR-124 in hippocampal neurons led to significant changes in the AGO2 binding of target mRNAs, resulting in subsequent upregulation of numerous miRNA target genes. Our data suggest that target redundancies are common among microRNA families. Together, these findings greatly enhance our understanding of the mechanisms and dynamics through which miRNAs regulate their target genes in neurons. Overall design: Analysis of the miRNA targetome in hippocampal neurons after inhibition of 2 different miRNAs. AAV5 injections into the hippocampus of adult C57BL/6 mice producing either of the following under a synapsin promoter: GFP only (Samples beginning with ''GFP124…'' or ''GFP125…''), GFP-miR124sp (Samples beginning with ''miR124…''), GFP-miR125sp (Samples beginning with ''miR125…''), GFP-AGO2-miR292sponge (samples ending with ''…292''), GFP-AGO2-miR124sponge (samples ending with ''…124''), GFP-AGO2-miR125sponge (samples ending with ''…125''). All other samples were sham-injected.
Identification of the miRNA targetome in hippocampal neurons using RIP-seq.
No sample metadata fields
View SamplesMicroRNAs (miRNAs) have been implicated in regulating multiple processes during brain development in various species. However, the function of miRNAs in human brain development remains largely unexplored. Here, we provide a comprehensive analysis of miRNA expression of regionalized neural progenitor cells derived from human embryonic stem cells and human fetal brain. We found mir-92b-3p and mir-130b-5p to be specifically associated with neural progenitors and several miRNAs that display both age-specific and region-specific expression patterns. Among these miRNAs, we identified miR-10 to be specifically expressed in the human hindbrain and spinal cord, while absent from rostral regions. We found that miR-10 regulates a large number of genes enriched for functions including transcription, actin cytoskeleton and ephrin receptor signaling. When overexpressed, miR-10 influences caudalization of human neural progenitors cells. Together, these data confirms a role for miRNAs in establishing different human neural progenitor populations. This data set also provides a comprehensive resource for future studies investigating the functional role of different miRNAs in human brain development. Overall design: Human embryonic stem cells (hESCs) were transduced with lentiviral vectors expressing either miR10a-GFP or miR10b-GFP. The expression of the vectors is Tet-regulated and they will only be expressed in the presence of Doxycycline. In order to detect direct targets of the miR10a and miR10b, we differentiated the trasduced hESCs for 14 days, and added doxycycline to only half of the groups - resulting in groups that are overexpressing miR10a or miR10b and some groups that are not overexpressing these miRNAs.
Comprehensive analysis of microRNA expression in regionalized human neural progenitor cells reveals microRNA-10 as a caudalizing factor.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MicroRNA regulate immune pathways in T-cells in multiple sclerosis (MS).
Specimen part, Disease, Disease stage
View SamplesMicroRNAs are small noncoding RNA molecules that are involved in the control of gene expression. To investigate the role of microRNA in multiple sclerosis (MS), we performed global microarray analyses of mRNA and microRNA in peripheral blood T-cells from relapsing-remitting MS patients and controls. We identified 2,452 regulated genes and 21 regulated microRNA that differed between MS patients and controls. By Kolmogorov-Smirnov test, 20 of 21 regulated microRNA were shown to affect the expression of their target genes, many of which are involved in the immune system. LIGHT (TNFSF14) was a microRNA target gene significantly decreased in MS. The down-regulation of mir-494 and predicted mRNA-target LIGHT was verified by real-time PCR and we could demonstrate decreased serum levels of LIGHT in MS. Thus, regulated microRNA were significantly associated with both gene and protein expression of a molecule in immunological pathways. These findings indicate that microRNA may be important regulatory molecules in T-cells in MS.
MicroRNA regulate immune pathways in T-cells in multiple sclerosis (MS).
Specimen part, Disease, Disease stage
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Identification and validation of single-sample breast cancer radiosensitivity gene expression predictors.
No sample metadata fields
View SamplesPurpose
Identification and validation of single-sample breast cancer radiosensitivity gene expression predictors.
No sample metadata fields
View SamplesThe presence of the PTPN22 risk variant (1858T) is associated to several autoimmune diseases including rheumatoid arthritis (RA). Despite a number of studies exploring the function of PTPN22 in T cells, the exact impact of the PTPN22 risk variant on T cell function in humans is still unclear. In this study, using RNA sequencing, we show that, upon TCR-activation, naïve CD4+ T cells carrying two PTPN22 risk alleles overexpress a limited number of genes including CFLAR and 4-1BB important for cytotoxic T cell differentiation. Moreover, an increased number of cytotoxic EOMES+ CD4+ T cells were observed in PTPN22 risk allele carriers, which negatively correlated with a decreased number of naïve T cells in older individuals. No difference in the frequency of other CD4+ T cell subsets (Th1, Th17, Tfh, Treg) was observed in PTPN22 risk allele carriers and Treg suppressive capacity was not altered. Finally, in synovial fluids of RA patients, an accumulation of EOMES+ CD4+ T cells was observed with a more pronounced production of Perforin-1 in PTPN22 risk allele carriers. Altogether, our data provide a novel mechanism of action of PTPN22 risk variant on CD4+ T-cell differentiation and identify EOMES+ CD4+ T cell as a relevant T cell subset in RA. Overall design: Healthy blood donors were selected based PTPN22 genotype, and RNA-sequencing was done on CD4 T cells
EOMES-positive CD4<sup>+</sup> T cells are increased in PTPN22 (1858T) risk allele carriers.
Sex, Age, Subject
View SamplesBackground: Exosomes are nanovesicles of endocytic origin believed to be involved in communication between cells. Recently, it has been shown that mast cell exosomes contain RNA named "exosomal shuttle RNA". The aim of this study was to evaluate whether exosomal shuttle RNA could play a role in the communication between human mast cells and between human mast cells and human CD34 positive progenitor cells. Results: Exosomes from the human mast cell line HMC-1 contain RNA. The exosomes contain no or very little ribosomal RNA compared to their donor cells. The mRNA and microRNA content in exosomes and their donor cells was examined using microarray analyses. We found 116 microRNA in the exosomes and 134 microRNA in the cells, from which some were expressed at different level. DNA microarray experiments revealed the presence of approximately 1800 mRNAs in the exosomes, which represent 15% of the donor cell mRNA content. Transfer experiments revealed that exosomes and their RNA can transfer to other HMC-1 cells and to CD34 positive progenitors. Conclusions: To conclude, HMC-1 exosomes contain mRNA and microRNA that can be transferred to other mast cells and to CD34 progenitors. This shuttle of exosomal RNA may represent a powerful mode of communication between cells where cells send genetic information to other cells over a distance via exosomes.
Characterization of mRNA and microRNA in human mast cell-derived exosomes and their transfer to other mast cells and blood CD34 progenitor cells.
Cell line
View SamplesThe goal of these studies was to determine the effects of fasting on skeletal muscle mRNA levels in healthy human subjects.
mRNA expression signatures of human skeletal muscle atrophy identify a natural compound that increases muscle mass.
Sex, Age, Specimen part, Treatment, Subject
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