Deregulated intracellular Ca2+ homeostasis underlies synaptic dysfunction and is a common feature in neurodegenerative processes, including Huntington's disease (HD). DREAM/calsenilin/KChIP-3 is a multifunctional Ca2+ binding protein that controls the expression level and/or the activity of several proteins related to Ca2+ homeostasis, neuronal excitability and neuronal survival. We found that expression of endogenous DREAM (DRE antagonist modulator) is reduced in the striatum of R6 mice, in STHdh-Q111/111 knock in striatal neurons and in HD patients. DREAM down regulation in R6 striatum occurs early after birth, well before the onset of motor coordination impairment, and could be part of an endogenous mechanism of neuroprotection, since i) R6/2 mice hemizygous for the DREAM gene (R6/2xDREAM+/-) showed delayed onset of locomotor impairment and prolonged lifespan, ii) motor impairment after chronic administration of 3-NPA was reduced in DREAM knockout mice and enhanced in daDREAM transgenic mice and, iii) lentiviral-mediated DREAM expression in STHdh-Q111/111 knock in cells sensitizes them to oxidative stress. Transcriptomic analysis showed that changes in gene expression in R6/2 striatum were notably reduced in R6/2xDREAM+/- striatum. Chronic administration of repaglinide, a molecule able to bind to DREAM in vitro and to accelerate its clearance in vivo, delayed the onset of motor dysfunction, reduced striatal loss and prolonged the lifespan in R6/2 mice. Furthermore, exposure to repaglinide protected STHdh-Q111/111 knock in striatal neurons sensitized to oxidative stress by lentiviral-mediated DREAM overexpression. Thus, genetic and pharmacological evidences disclose a role for DREAM silencing in early neuroprotective mechanisms in HD.
Activating transcription factor 6 derepression mediates neuroprotection in Huntington disease.
Specimen part
View SamplesObesity is a chronic, complex and multifactorial disease that has reached pandemia levels and is becoming a serious health problem. Intestinal microbiota is considered a main factor that affects body weight and fat mass, which points toward a critical role in the development of obesity. In this sense, probiotic bacteria might modulate the intestinal microbiota and the mucosal-associated lymphoid tissue. The aim of this study was to investigate the effects of L. paracasei, L. rhamnosus and B. breve feeding on the intestinal mucosa gene expression in a genetic animal model of obesity.
Adamdec1, Ednrb and Ptgs1/Cox1, inflammation genes upregulated in the intestinal mucosa of obese rats, are downregulated by three probiotic strains.
Specimen part
View SamplesHepatic iron overload is a risk factor for progression of hepatocellular carcinoma (HCC), although the molecular mechanisms underlying this association have remained unclear. We now show that the iron-sensing ubiquitin ligase FBXL5 is previously unrecognized oncosuppressor in liver carcinogenesis in mice. Hepatocellular iron overload evoked by FBXL5 ablation gives rise to oxidative stress, tissue damage, inflammation and compensatory proliferation in hepatocytes and to consequent promotion of liver carcinogenesis induced by exposure to a chemical carcinogen. The tumor-promoting effect of FBXL5 deficiency in the liver is also operative in a model of virus-induced HCC. FBXL5-deficient mice thus constitute the first genetically engineered mouse model of liver carcinogenesis induced by iron overload. Dysregulation of FBXL5-mediated cellular iron homeostasis was also found to be associated with poor prognosis in human HCC, implicating FBXL5 plays a significant role in defense against hepatocarcinogenesis. Overall design: Total RNA was extracted from the nontumor and tumor tissue of an Alb-Cre/Fbxl5F/F male mouse (nontumor, n = 5; tumor, n = 5) or two littermate control Fbxl5F/F mice (nontumor, n = 6; tumor, n = 6) at 45 weeks of age.
Disruption of FBXL5-mediated cellular iron homeostasis promotes liver carcinogenesis.
Specimen part, Cell line, Subject
View SamplesYeast lacking the H3 or H4 amino termini, and corresponding wild type strains, were grown in synthetic media. These conditions induce Gcn4-activated transcription.
Contribution of the histone H3 and H4 amino termini to Gcn4p- and Gcn5p-mediated transcription in yeast.
No sample metadata fields
View SamplesAbf1 and Rap1 are General Regulatory Factors that contribute to transcriptional activation of a large number of genes, as well as to replication, silencing, and telomere structure in yeast. In spite of their widespread roles in transcription, the scope of their functional targets genome-wide has not been previously determined. We have used microarrays to examine the contribution of these essential GRFs to transcription genome-wide, by using ts mutants that dissociate from their binding sites at 37 C. We combined this data with published ChIP-chip studies and motif analysis to identify probable direct targets for Abf1 and Rap1. We also identified a substantial number of genes likely to bind Rap1 or Abf1, but not affected by loss of GRF binding. Interestingly, the results strongly suggest that Rap1 can contribute to gene activation from farther upstream than can Abf1. Also, consistent with previous work, more genes that bind Abf1 are unaffected by loss of binding than those that bind Rap1. Finally, we showed for several such genes that the Abf1 C-terminal region, which contains the putative activation domain, is not needed to confer this peculiar "memory effect" that allows continued transcription after loss of Abf1 binding.
Genome-wide analysis of transcriptional dependence and probable target sites for Abf1 and Rap1 in Saccharomyces cerevisiae.
No sample metadata fields
View SamplesSignal intensity data for rpd3 delete, H3delta(1-28), H3(K4,9,14,18,23,27Q), H4delta(2-26), H4(K5,8,12,16Q), rpd3 delete H3delta(1-28), and rpd3 delete H4(K5,8,12,16Q) yeast grown in rich (YPD) media
Genome-wide analysis of the relationship between transcriptional regulation by Rpd3p and the histone H3 and H4 amino termini in budding yeast.
No sample metadata fields
View SamplesDifferential gene expression between groups of homogenous cell types is a biological question whose time has come. RNA can be extracted from small numbers of cells, such as those isolated by laser capture microdissection, but the small amounts obtained often require amplification to enable whole genome transcriptome profiling by technologies such as microarray analysis and RNA-seq. Recently, advances in amplification procedures make amplification directly from whole cell lysates possible. The aim of this study was to compare two amplification systems for variations in observed RNA abundance attributable to the amplification procedure for use with small quantities of cells isolated by laser capture microdissection. Arabidopsis root cells undergoing giant cell formation due to nematode infestation and un-infested control root cells were laser captured and used to evaluate 2 amplification systems. One, NuGEN's WT-Ovation Pico amplification system, uses total RNA as starting material while the other, NuGEN's WT-One-Direct Amplification system, uses lysate containing the captured cells. The reproducibility of whole genome transcript profiling and correlations of both systems were investigated after microarray analysis. The NuGEN WT-Ovation One-Direct system was less reproducible and more variable than the NuGEN WT-Ovation Pico system. The NuGEN WT-Ovation Pico Amplification kit resulted in the detection of thousands of genes differentially expressed genes between giant cells and control cells. This is in marked contrast to the relatively few genes detected after amplification with the NuGEN WT-Ovation One-Direct Amplification kit.
Comparison between NuGEN's WT-Ovation Pico and one-direct amplification systems.
Specimen part, Time
View SamplesFzd2 is a Wnt receptor expressed in the embryonic lung. We made a conditional knockout of Fzd2 to specifically address the role of signaling through Fzd2 in lung epithelial development.
Wnt ligand/Frizzled 2 receptor signaling regulates tube shape and branch-point formation in the lung through control of epithelial cell shape.
Specimen part
View SamplesWe analysed the genexpression of dental follicle cells (DFCs) after 3 days osteogenic differentiation with BMP2 after transfection with a DLX3 plasmid (pDLX3) and after transfection with an empty plasmid (pEV)
A protein kinase A (PKA)/β-catenin pathway sustains the BMP2/DLX3-induced osteogenic differentiation in dental follicle cells (DFCs).
Specimen part
View SamplesConditional IRF8 KO mice (mice with a conditional allele of Irf8 crossed with CD19-Cre mice) showed increased numbers of both Gene expression data spleen marginal zone (MZ) and Gene expression data spleen follicular (FO) B cells compared to control mice.
IFN regulatory factor 8 restricts the size of the marginal zone and follicular B cell pools.
No sample metadata fields
View Samples