Project description:Transcriptome analysis of mRNA samples purified from developing cerebellar granule cells and ES cell-derived granule cells using translating ribosome affinity purification (TRAP) method. Although mechanisms underlying early steps in cerebellar development are known, evidence is lacking on genetic and epigenetic changes during the establishment of the synaptic circuitry. Using metagene analysis, we report pivotal changes in multiple reactomes of epigenetic pathway genes in cerebellar granule cells (GCs) during circuit formation. During this stage, Tet genes are up-regulated and vitamin C activation of Tet enzymes increases the levels of 5-hydroxymethylcytosine (5hmC) at exon start sites of up-regulated genes, notably axon guidance genes and ion channel genes. Knockdown of Tet1 and Tet3 by RNA interference in ex vivo cerebellar slice cultures inhibits dendritic arborization of developing GCs, a critical step in circuit formation. These findings demonstrate a role for Tet genes and chromatin remodeling genes in the formation of cerebellar circuitry. We analyzed gene expression of cerebellar granule cells and ES cell-derived granule cells using the Affymetrix mouse gene 1.0 ST platform. Array data was processed by metagene analysis which was developed by the Broad Institute.
Project description:We investigated the role of Bmi1 in Shh-mediated shift in gene expression levels Experiment Overall Design: Primary cerebellar granule cell precursors (GCPs) cultures were prepared from P7 Bmi-1-/- or wild type mice as described before {Messer, 1977 #810}. Cells were grown in Dulbecco MEM high Glucose, supplemented with 10% FCS glutamine, 20 mM KCl and penicillinâstreptomycin for 24 hours. Shh (R&D Systems) if appropriate was added for 24 hours to give at final concentration of 3 mg/ml. Experiment Overall Design: We performed 3 biological replicates for both WT and Bmi-1-/- cultures, and 2 biological replicates for both WT and Bmi-1-/- cultures, treated with Shh. Experiment Overall Design: Total RNA was isolated using RNeasy Mini Kit (Qiagen) and reverse-transcribed into double-stranded cDNA with One-Cycle cDNA Synthesis Kit (Affymetrix Inc., P/N 900431, Santa Clara, CA) and labelled biotin. Biotin-labeled cRNA samples were fragmented randomly to 35â200 bp and hybridized to GeneChip® Mouse Genome 430 2.0. An Affymetrix GeneChip Scanner 3000 (Affymetrix Inc., Santa Clara, CA) was used to measure the fluorescent intensity emitted by the labeled target.
Project description:The molecular mechanism(s) leading to Purkinje neuron loss in the neurodegenerative disorder Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS) are limited by the complex morphology of this cell type. Purkinje neurons are notoriously difficult to isolate and maintain in culture presenting considerable difficultly to identify molecular changes in response to riboCGG repeat-containing mRNA that induces neurotoxicity in FXTAS. Several studies have uncovered a number of RNA binding proteins involved in translation that aberrantly interact with the toxic RNA; however, whether these interactions alter the translational profile of cells has not been investigated. Here we employ bacTRAP translational profiling to demonstrate that Purkinje neurons ectopically expressing 90 CGG repeats exhibit a dramatic change in their translational profile even prior to the onset of riboCGG-induced phenotypes. This approach identified nearly 500 transcripts that are differentially associated with ribosomes in r(CGG)90-expressing mice. Functional annotation cluster analysis revealed broad ontologies enriched in the r(CGG)90 list, including RNA binding and response to stress. Intriguingly, a transcript for the Tardbp gene, implicated in a number of other neurodegenerative disorders, exhibits altered association with ribosomes in the presence of r(CGG)90 repeats. We therefore tested and showed that reduced association of Tardbp mRNA with the ribosomes results in a loss of TDP-43 protein expression in r(CGG)90–expressing Purkinje neurons. Furthermore, we showed that TDP-43 could modulate the rCGG repeat-mediated toxicity in a Drosophila model that we developed previously. These findings together suggest translational dysregulation may be an underlying mechanism of riboCGG-induced neurotoxicity and provide insight into the pathogenicity of FXTASBAC-trap studies of Purkinje cels in normal and mutant mice Looking for cell type specific gene expression differences caused by mutation in FMR1 using BAC-Trap RNA capture assay. A cutoff value of 4.5 for mean probe_set mean across all 18 hybridizations was used to determine a cutoff for expression in Purkinje cells. This 16040 corresponded to a mean value of at least 3.4323 in the 4week time point. L7CGG90Fmr1:Pcp2 BAC (r(CGG)90 BAC) and wild-type:L7/Pcp2 BAC (WT BAC) transgenic mice used in this study have a 50% C57B6 and 50% FVB genetic background and were derived from the same parents by crossing L7CGG90Fmr1 heterozygote transgenics (100% C57B6 background) with L7/Pcp2eEGFPL10a BAC homozygous transgenics (100% FVB background). All mice reported were F1 progeny and were therefore hemizygous for one or both transgenes. Littermate wild-type mice were used for all experiments whenever possible.
Project description:Thyroid carcinoma (TC) is generally associated with good prognosis, nevertheless no effective treatments are available for aggressive forms not cured by current therapies. We previously identified the coatomer protein complex zeta 1 (COPZ1), as a new putative therapeutic target for TC, since its depletion impairs the viability of tumor cells, leads to abortive autophagy, ER stress, unfolded protein response and apoptosis, and reduces the tumor growth of TC xenograft models. In this study, by combining genomic, proteomic and functional approaches, we provided evidence that COPZ1 silencing stimulates a type I IFN-mediated viral mimicry response, boosts the production of several inflammatory molecules and finally induces immunogenic cell death, which, in turn, promotes dendritic cell maturation and subsequent activation of T cells. Collectively, our findings support the notion that COPZ1 targeting can be exploited as a new strategy to kill cancer cells with the subsequent involvement of an anti-tumor immune response.
Project description:Pig breeds have different attitude to traits like growth rate, carcass composition and reproduction parameters as well as other traits. These traits considered as external traits or end phenotypes are the outcome of complex biological processes and interactions. The main goal of pig breeding programs and the basis for crossbreeding is finding a balance between these traits. In pig production, Large White and Duroc breeds are commonly used to optimise respectively fertility and growth ability and differ on several production traits, indeed the first breed as a high fertility characters whereas Duroc is used as terminal sire for her growth performance and good carcass quality traits. In this study, we have used a quantitative label-free LC-MS proteomics approach to characterise and compare the liver proteome of two heavy Italian pig breeds, Italian Duroc and Italian Large White to identify difference due to their different genetic background. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 703094.
Project description:The intent of the experiment is to compare the transcriptomes of CGNs expressing Zeb1 or Hif1 to determine potential common targets and to determine whether there is a hypoxic signature in CGNs isolated from the early postnatal cerebellum.
Project description:This experiment captures the expression data obtained from mouse cerebellar granule neurons (CGN) at different time points of post-natal development, both in wild type samples (P0, P7, and P15) and in CGN electroporated with vectors expressing transcription factors Zeb1 and Hes1 (both P7).
Project description:Neuronal cultures were treated with candesartan at neuroprotective concentrations followed by excitotoxic glutamate amounts. Candesartan significantly reduced glutamate-induced inflammation. To provide mechanistic insight into the potential targets and pathways that may underlie these benefits, we performed genome wide expression profile analysis and evaluated the data by Ingenuity Pathway Analysis (IPA) and Gene Set Enrichment Analysis (GSEA). We found that the inflammation signal transduction pathways were major components of the neuronal response to glutamate excitotoxicity, and that candesartan significantly ameliorated glutamate-induced alterations in gene expression. Further analysis showed significant associations of these genes with two independent published networks identified by microarray analysis of hippocampal samples obtained post-mortem from brains of patients diagnosed with AD . 8 days old rat Primary cerebellar granule cells (CGCs) were treated with DMSO, Glutamate, Candesartan or Glutamate +candesartan. Four replicates of each treatment were done.
Project description:Medulloblastomas (MBs) are cerebellar tumors that can be classified into molecularly distinct subgroups that differ in pathology and prognosis. The mechanisms that underlie subgroup specification are largely unknown. While human SHH MBs express MYCN, Group3 (G3) MBs are associated with c-MYC (MYC) overexpression and often show metastasis that confers a poor prognosis. Although MYC proteins are thought to be functionally exchangeable, ectopic expression of Myc or N-myc in Trp53-/-;Cdkn2c-/- cerebellar granule neuron progenitors (GNPs) induces G3 and SHH MBs, respectively, demonstrating that each Myc protein has distinct biological properties. We now show that Myc and N-myc differ in their affinity to Miz1 and that Myc, but not N-myc, effectively recruits Miz1 to its target sites on chromatin. The interaction of Myc with Miz1 is required for the genesis of G3 MB. Myc suppresses ciliogenesis and âreprogramsâ the transcriptome of SHH-dependent GNPs to stem-like cells by repressing genes highly expressed in SHH MB via Miz1. Consistently, target genes of Myc/Miz1 are repressed in human G3 MBs but not in other MB subgroups. Collectively, the data show that the interaction of Myc with Miz1 is a defining hallmark of G3 MB development. In this study, we show that Myc and N-myc differ in their affinity for Miz1, and Myc/Miz1 interaction is required for Group3 medulloblastoma (MB). The gene expression profiles of these tumors were compared to our previously published Group3 MB model as well as SHH model of MB (Kawachi et al., 2012, Cancer Cell). Cerebellar granule neuron progenitors (GNPs) [dka220-222] from postnatal (P) 6 Math1-GFP;Trp53-/-;Cdkn2c-/-. For SHH medulloblastomas, [dka204-206] and [blm015-017 or dka050-dka051], spontaneous medulloblastomas from Cdkn2c-/-;Trp53Fl/Fl;Nestin-Cre (Kawachi et al., 2012, Cancer Cell) and Ptch1+/-;Cdkn2c-/- (Uziel et al., 2005, Genes Dev) were used, respectively. Myc- [dka201-203] and MycV394D (termed MycVD thereafter)- [bvo017-bvo023] tumors were from Trp53-/-;Cdkn2c-/- cerebella of P6-P7 pups. Myc/ÎPOZ tumors [bvo002-bvo006] were obtained from Trp5Fl/Fl;Miz1ÎPOZ/POZ;Nestin-Cre cerebella of P6-P7 pups.