Project description:Development of meso-diencephalic dopamine (mdDA) neurons requires the combined actions of the orphan nuclear receptor Nurr1 and the paired-like homeobox transcription factor Pitx3. Whereas all mdDA neurons require Nurr1 for expression of Th and survival, dependence on Pitx3 is only displayed by the mdDA subpopulation that will form the substantia nigra (SNc). Previously, we demonstrated that Pitx3-/- embryos lack the expression of the retinoic acid (RA)-generating enzyme Ahd2, which is normally selectively expressed in the Pitx3-dependent DA neurons of the SNc. Restoring RA-signaling in Pitx3-/- embryos revealed a selective dependence of SNc neurons on the presence of RA for differentiation into Th-positive neurons and maintenance throughout embryonic development. Whereas these data are suggestive of an important developmental role for RA in neurons of the SNc, it remained unclear whether other Nurr1 and Pitx3 target genes depend on RA signaling in a manner similar to Th. In search for genes that were affected in Pitx3-deficient mdDA neurons and restored upon embryonic RA treatment, we provide evidence that Delta-like 1, D2R (Drd2) and TH are regulated by Pitx3 and RA signaling, influencing the mdDA terminal differentiated phenotype. Furthermore, we show that regulation of Ahd2-mediated RA-signaling represents only one aspect of the Pitx3 downstream cascade, since Vmat2, Dat, Ahd2 (Aldh1a1), En1, En2 and Cck were unaffected by RA treatment and are (subset) specifically modulated by Pitx3. In conclusion, our data reveal several RA-dependent and -independent aspects of the Pitx3-regulated gene cascade suggesting that Pitx3 acts on multiple levels in the molecular subset-specification of mdDA neurons. RNA was isolated from dissected ventral midbrains of E14.5 Pitx3-/- and Pitx3+/+ mouse embryos. 3 Experimental samples each consisting of 3 Pitx3-/- ventral midbrains were hybridized to reference RNA derived from 10 Pitx3+/+ ventral midbrains
Project description:Induced pluripotent stem cells (iPSCs) hold great promise for in vitro disease modeling and cell replacement therapy for Parkinson’s disease (PD). Both applications crucially require an in-depth profiling of the disease-relevant, iPSC-derived cell type. Midbrain dopaminergic (mDA) neurons derived from pluripotent stem cells are of substantial interest because of their instrumental value for PD therapy. IPSC-derived mDA neuron-like cells have been generated, however, detailed genetic and epigenetic characterization of strictly purified in vitro generated DA neurons has so far lagged behind. We generated mouse Pitx3gfp/+ iPSC-derived DA neurons that, after fluorescent activated cell sorting (FACS) allowed comprehensive comparison to mesodiencephalic dopaminergic (mdDA) neurons from Fac-sorted Pitx3gfp/+ ventral midbrains. We performed detailed analysis of global gene expression and genome-scale DNA methylation of CpG islands (CGIs) by reduced representation bisulfite sequencing. The reprogramming pathway from fibroblasts to iPSCs left parental cell footprints for both gene expression and DNA methylation. However, most gene expression patterns of iPSC-derived DA neurons closely resembled that of primary mdDA neurons with the strongest correlations for mdDA specific genes. Also, for DNA methylation patterns, high similarities were found for the vast majority of CGIs when comparing primary mdDA neurons with iPSC-derived DA neurons. Additionally, we found de novo DNA methylation during in vitro differentiation for hundreds of genes specifically in lineage-committed neural precursors that persisted in iPSC-derived DA neurons. Our study provides novel detailed characteristics of iPSC-derived DA neurons in comparison to the primary cell type. These findings add important information to our knowledge about these biomedically highly valuable, in vitro generated neurons. Microarray expression study comparing 3 samples of facs-sorted, Pitx3-gfp positive cells from each experimental group to a common reference consisting of adult mouse midbrain RNA. Each sample was analysed in normal and opposite dye orientation.
Project description:Inoculation of endophyte-free (E-) Theobroma cacao leaves with Colletotrichum tropicale (E+), the dominant foliar fungal endophyte in healthy T. cacao, induced significant changes in the expression of hundreds of host genes. Further, E+ leaves exhibit enhanced pathogen resistance, increased lignin and cellulose content, reduced maximum rates of photosynthesis (Amax), and enrichment of nitrogen-15 and carbon-13 isotopes that all correspond to the changes in expression of specific functional genes in related pathways. Moreover, a cacao gene highly up-regulated in E+ leaves increases pathogen resistance apart from any direct endophyte effects. Thus, benefits of increased pathogen resistance in E+ plants are partially due to enhanced induction of intrinsic host defense pathways, and potential costs include reduced photosynthetic capacity and endophyte metabolism of host tissues. Similar effects are likely to be properties of most plant-endophyte interactions, suggesting general relevance to the design and interpretation of studies of genetic and phenotypic expression in plants. The objective of this experiment was to identify Theobroma cacao genes that are differentially expressed between leaves inoculated with fungal endophyte Colletotrichum tropicale (E+ leaves) and control un-inoculated leaves (E- leaves) 14 days post last endophyte inoculation. The experiment was conducted in a Percival growth chambers (model I35LL, 115 volts, 1/4 Hp, series: 8503122.16, Percival Scientific, Inc., Perry IA) with 12/12 h light/dark photoperiod and temperatures of 30M-BM-:C and 26M-BM-:C respectively. A total of four endophyte spore inoculations (1X10^6 spore/ml) were made by aspersion to a group of T. cacao seedlings and a second group of seedlings were maintained as un-inoculated. Then six biological replicates per treatment (E+ leaves and six E- leaves) each one belonging from a different seedling were collected and processed for a two color oligo microarray analysis. A total of six arrays were processed, each one hybridized to an inoculated and a control un-inoculated sample in a dye swap design.
Project description:Development of meso-diencephalic dopamine (mdDA) neurons requires the combined actions of the orphan nuclear receptor Nurr1 and the paired-like homeobox transcription factor Pitx3. Whereas all mdDA neurons require Nurr1 for expression of Th and survival, dependence on Pitx3 is only displayed by the mdDA subpopulation that will form the substantia nigra (SNc). Previously, we demonstrated that Pitx3-/- embryos lack the expression of the retinoic acid (RA)-generating enzyme Ahd2, which is normally selectively expressed in the Pitx3-dependent DA neurons of the SNc. Restoring RA-signaling in Pitx3-/- embryos revealed a selective dependence of SNc neurons on the presence of RA for differentiation into Th-positive neurons and maintenance throughout embryonic development. Whereas these data are suggestive of an important developmental role for RA in neurons of the SNc, it remained unclear whether other Nurr1 and Pitx3 target genes depend on RA signaling in a manner similar to Th. In search for genes that were affected in Pitx3-deficient mdDA neurons and restored upon embryonic RA treatment, we provide evidence that Delta-like 1, D2R (Drd2) and TH are regulated by Pitx3 and RA signaling, influencing the mdDA terminal differentiated phenotype. Furthermore, we show that regulation of Ahd2-mediated RA-signaling represents only one aspect of the Pitx3 downstream cascade, since Vmat2, Dat, Ahd2 (Aldh1a1), En1, En2 and Cck were unaffected by RA treatment and are (subset) specifically modulated by Pitx3. In conclusion, our data reveal several RA-dependent and -independent aspects of the Pitx3-regulated gene cascade suggesting that Pitx3 acts on multiple levels in the molecular subset-specification of mdDA neurons.
Project description:Expression analysis of Drosophila embryos with mnn overexpression, and adults with mnn deletion. Keywords: Expression analysis Described in Cerrato et al, Dev Biol. 2006 Oct 1;298(1):59-70.
Project description:Macrophage death in advanced atherosclerotic lesions is a key event in the conversion of benign lesions to vulnerable plaques. One fundamental transcription factor that has been shown to play a pivotal role in cell death/survival is nuclear factor kB (NF-kB). Still, the relevance of this key transcription factor for macrophage-derived foam cell survival has not been unequivocally resolved at the molecular level. THP-1 monocytic cell lines were generated in which NF-kB activation is specifically inhibited by overexpression of a trans-dominant, non-degradable form of IkBa (IkBa (32A/36A)) under control of the macrophage-specific SR-A promoter. A diminished lipid loading during NF-κB inhibition during foam cell formation was accompanied by increased cell death. A genome-wide expression profile of NF-kB-dependent genes during foam cell formation was established showing a widespread effect on the macrophage transcriptome. The three largest functional gene clusters identified and validated by independent techniques, were those involved in lipid metabolism, apoptosis and oxidative stress. The net result of these complex gene expression changes invoked by inhibition of NF-κB activation during lipid loading is a reduction of foam cell survival through caspase-dependent apoptosis. Thus, the NF-kB-dependent gene repertoire seems essential for sustained macrophage survival during the process of pathological lipid loading. Keywords: genetic modification, lipid loading, timecourse THP-1 cells and two different THP-1 IkB mutants (A3 and A12) were exposed to PMA to induce macrophage differentiation and subsequently loaded with oxidized LDL or vehicle for 5 or 8 days. One replicate per array, a total of 15 arrays. A common reference pool, composed of an equimolar mixture of all samples, was labeled with Cy3 and hybridized against the Cy5-labeled experimental sample.
Project description:Meso-diencephalic dopaminergic (mdDA) neurons are critical for motor control and cognitive functioning and their loss or dysfunction is associated with disorders such as Parkinson’s disease (PD), schizophrenia and addiction. However, relatively little is known about the molecular mechanisms underlying mdDA neuron development and maintenance. Here, we determined the spatiotemporal map of genes involved in the development of mdDA neurons to gain further insights into their molecular programming. Genome-wide gene expression profiles of the developing ventral mesencephalon (VM) were compared at different developmental stages leading to the identification of novel regulatory roles of neuronal signaling through nicotinic acthylcholine receptors (Chrna6 and Chrnb3 subunits) and the identification of novel transcription factors (OC1 and 2)) involved in the generation of mdDA neuronal field. We show here that Pitx3 in cooperation with Nurr1 are the critical components in the activation of the Chrna6 and b3 subunits in mdDA neurons. Furthermore, we provide evidence of two divergent regulatory pathways resulting in the expression of Chrna6 and Chrnb3 respectively. Embryonic ventral midbrain (VM) tissue was used to generate RNA samples for microarray analysis. Each sample consists of pooled RNA from three embryonic VMs, and is hybridized twice (in both dye orientations) against a common reference RNA (KC001-ref) consisting of pooled RNA from adult VMs. Each embryonic stages E10.5, E11.5, E12.5 and E13.5 is analysed from three independant samples.
Project description:The goal of this study is to explore genes that are differentially expressed in E. coli C strains (wt and a butanol-tolerant mutant) after 1-butanol treatment. The butanol-tolerant mutant strain PKH5000 (denoted by 'E' for 'evolved') were derived from KCTC 2571 (wt) (denoted by 'A' for 'ancestral') by proton beam irradiation. 0 and 1 in sample title mean before and after butanol treatment, respectively. All microarray experiments were carried out in triplicate (rep1-3). Probes were spotted in duplicate on separate area of each microarray slide, which produces two GPR files (a and b suffixes).
Project description:Will be added/updated once the manuscript is finalized. Cardiocondyla obscurior queens. Three treatments: virgin queens, queens mated by real males, queens sham-mated (by sterile males). Queens collected 1 week and 8 week after mating. seven loops for queens collected 1 week after mating; nine loops for queens collected 8 weeks after mating. Five direct comparisons (with dye-swaps... so 10 arrays) were done of between 1 week and 8 week samples of queens mated by real males. Each sample is RNA from two queens (from different colonies). Samples were hybridized against Solenopsis invicta microarrays (signal was detectable for most clones!)