Project description:We identify a brain-specific microRNA—miR-128—that represses Nonsense Mediated mRNA Decay (NMD) and thereby controls batteries of transcripts in neural cells. miR-128 represses NMD by targeting the RNA helicase UPF1 and the exon-junction complex core component MLN51. We employed exon arrays for this analysis, as this platform detects expression levels of individual exons and thus allows detection of not only differentially expressed transcripts (DETs), but also alternative isoform transcripts (AITs). The latter is particularly relevant to our study because alternative RNA processing events (e.g., RNA splicing, alternative promoter usage, and alternative polyadenylation-site usage) often place a translation termination codon in a premature context and thereby trigger NMD. Compare different expressed genes and transcript isoforms in mouse NSCs miR-128 positive vs miR-128 negative (Control). Mouse NSCs, that do not normally express miR-128, were nucleofected with either miR-128 (biological triplicates were analysed) or miR-Control (biological triplicates). RNA was extracted 72hrs later, and Exon Array was performed to identify target genes.
Project description:Circular RNAs (circRNAs), a diverse class of ncRNAs highly enriched in developing neurons, play roles in local protein synthesis and synaptic plasticity. However, distinguishing functional from non-functional circRNAs is challenged by their abundance, tissue specificity and splicing variability. To address this, we conducted a RNAi knockdown screen targeting 32 highly expressed, conserved circRNAs enriched in dendritic processes. circRERE isoforms emerged as regulators of dendritic synapse density and electrophysiological characteristics. mRNA-seq supports the dysregulation of synaptic genes, particularly miR-128-3p-sensitive transcripts. MiR-128-3p activity and expression are reduced, with circRERE possessing multiple miR-128-3p binding sites, suggesting a protective interaction supported by a rescue of the synaptic phenotype upon miR-128-3p overexpression. Conversely, circRERE overexpression with intact miR-128-3p sites rescued the synaptic phenotype and independently increased miR-128-3p levels. These findings demonstrate the necessity for the broad characterization of circRNAs in the nervous system to comprehensively understand their influence on essential non-coding RNA regulatory networks.
Project description:Circular RNAs (circRNAs), a diverse class of ncRNAs highly enriched in developing neurons, play roles in local protein synthesis and synaptic plasticity. However, distinguishing functional from non-functional circRNAs is challenged by their abundance, tissue specificity and splicing variability. To address this, we conducted a RNAi knockdown screen targeting 32 highly expressed, conserved circRNAs enriched in dendritic processes. circRERE isoforms emerged as regulators of dendritic synapse density and electrophysiological characteristics. mRNA-seq supports the dysregulation of synaptic genes, particularly miR-128-3p-sensitive transcripts. MiR-128-3p activity and expression are reduced, with circRERE possessing multiple miR-128-3p binding sites, suggesting a protective interaction supported by a rescue of the synaptic phenotype upon miR-128-3p overexpression. Conversely, circRERE overexpression with intact miR-128-3p sites rescued the synaptic phenotype and independently increased miR-128-3p levels. These findings demonstrate the necessity for the broad characterization of circRNAs in the nervous system to comprehensively understand their influence on essential non-coding RNA regulatory networks.
Project description:RNAseq analysis of purified splenic CD19+ B lymphocytes from the hRORxTCL1 mouse model treated with 2A2-miR-29b-ILP or 2A2-scramble-ILP. Moreover, 128 of the 233 differentially expressed genes are related to cell growth and proliferation.
Project description:<p>RNA sequencing was performed on human DRGs and relative gene abundances were calculated.</p> <p>Various analyses were performed:</p> <p> <ol> <li>Human DRG gene expression profiles were contrasted with a panel of gene expression profiles of relevant tissues in human and mouse ( integrating, among other sources, datasets from ENCODE and GTex ) in order to identify.</li> <ol type="a"> <li>DRG-enriched gene expression, co-expression modules of DRG-expressed genes, and key transcriptional regulators in humans.</li> <li>Contrasting the human and mouse DRG transcriptomes to identify DRG-enriched gene expression patterns that were conserved between human and mouse, identifying putative cell types of expression of these genes, and potential known drugs that might target the corresponding gene products.</li> <li>Characterization of non-coding RNA profile of human and mouse DRGs.</li> <li>Characterization of DRG-enriched alternative splicing and alternative transcription start site usage based transcript variants in humans and mouse, and the overlap between these two species.</li> <li>Contrasting of human DRG and GTex human tibial nerve samples to identify putative axonally transported mRNAs in sensory neurons.</li> </ol> <li>Human DRG transcriptomes from donors suffering from neuropathic and/or chronic pain were contrasted with controls to identify.</li> <ol type="a"> <li>Differentially expressed genes, pathways and regulators path play a potential role in neuronal plasticity, electrophysiological activity, immune signaling and response.</li> <li>Predictive models (Random Forests) were built to jointly predict the sex and pain state of samples based on information contained solely in autosomal gene expression profile.</li> <li>Gene co-expression modules were identified and gene set enrichment analysis performed.to identify sample - pathway associations, and to broadly characterize plasticity in human DRG cell types.</li> </ol> </ol> </p>
Project description:Tuberous Sclerosis Complex (TSC) is a rare genetic disorder that results from a mutation in the TSC1 or TSC2 genes leading to constitutive activation of the mechanistic target of rapamycin complex 1 (mTORC1). TSC is associated with autism, intellectual disability and severe epilepsy. Cortical tubers are believed to represent the neuropathological substrates of these disabling manifestations in TSC. In the presented study we used high-throughput RNA sequencing in combination with systems-based computational approaches to investigate the complexity of the TSC molecular network. Overall we detected 438 differentially expressed genes and 991 differentially expressed small non-coding RNAs in cortical tubers compared to autopsy control brain tissue. We observed increased expression of genes associated with inflammatory, innate and adaptive immune responses. In contrast, we observed a down-regulation of genes associated with neurogenesis and glutamate receptor signaling. MicroRNAs represented the largest class of over-expressed small non-coding RNA species in tubers. In particular, our analysis revealed that the miR-34 family (including miR-34a, miR-34b and miR-34c) was significantly over-expressed. Functional studies demonstrated the ability of miR-34b to modulate neurite outgrowth in mouse primary hippocampal neuronal cultures. This study provides new insights into the TSC transcriptomic network along with the identification of potential new treatment targets.
Project description:MicroRNA regulates protein expression of cells by repressing translation of specific target messenger transcripts. Loss of the neuron specific microRNA miR-128 in Dopamine D1-receptor expressing neurons in the murine striatum (D1-MSNs) lead to increased neuronal excitability, locomotor hyperactivity and fatal epilepsy. To examine expression changes in the absence of miR-128 in D1-MSNs, we used mice expressing EGFP-tagged ribosomes in D1-MSNs with either D1-MSN-specific homozygous deletion of miR-128-2 locus or no deletion. Transcripts co-immunoprecipitated with tagged ribosomes were analyzed by microarray.
Project description:MicroRNA regulates protein expression of cells by repressing translation of specific target messenger transcripts. Loss of the neuron specific microRNA miR-128 in Dopamine D1-receptor expressing neurons in the murine striatum (D1-MSNs) lead to increased neuronal excitability, locomotor hyperactivity and fatal epilepsy. To examine expression changes in the absence of miR-128 in D1-MSNs, we used mice expressing EGFP-tagged ribosomes in D1-MSNs with either D1-MSN-specific homozygous deletion of miR-128-2 locus or no deletion. Transcripts co-immunoprecipitated with tagged ribosomes were analyzed by microarray. 9 mutant animals ( D1-MSN-tagged ribosome; D1-MSN specific miR-128-2 homozygous deletion) and 7 age matched littermate control animals (D1-MSN-tagged ribosome only).
Project description:About half of all human and mouse miRNA genes are located within introns of protein-coding genes. Despite this, little is known about functional interactions between miRNAs and their host genes. The intronic miRNA miR-128 regulates neuronal excitability and controls dendrite outgrowth of projection neurons during development of the mouse cerebral cortex. Its host genes R3hdm1 and Arpp21 encode highly conserved, putative RNA-binding proteins. Here we use iCLIP to describe the RNA-binding activity of ARPP21, which recognizes uridine-rich sequences with exquisite sensitivity for 3UTRs. Surprisingly, ARPP21 antagonizes miR-128 activity by co-regulating a subset of miR-128 target mRNAs enriched for neurodevelopmental functions. In contrast to miR-128, we show that ARPP21 acts as a positive post-transcriptional regulator, at least in part through interaction with the eukaryotic translation initiation complex eIF4F. This molecular antagonism is also reflected in inverse activities during dendritogenesis: miR-128 overexpression or knockdown of ARPP21 reduces dendritic complexity; ectopic ARPP21 leads to an increase. The regulatory interaction between ARPP21 and miR-128 is a unique example of convergent function by two products of a single gene.