In the mammalian central nervous system (CNS) an important contingent of dopaminergic neurons are localized in the substantia nigra and in the ventral tegmental area of the ventral midbrain. They constitute an anatomically and functionally heterogeneous group of cells involved in a variety of regulatory mechanisms, from locomotion to emotional/motivational behavior. Midbrain dopaminergic neuron (mDA) primary cultures represent a useful tool to study molecular mechanisms involved in their development and maintenance. Considerable information has been gathered on the mDA neurons development and maturation in vivo, as well as on the molecular features of mDA primary cultures. Here we investigated in detail the gene expression differences between the tissue of origin and ventral midbrain primary cultures enriched in mDA neurons, using microarray technique. We integrated the results based on different re-annotations of the microarray probes. By using knowledge-based gene network techniques and promoter sequence analysis, we also uncovered mechanisms that might regulate the expression of CNS genes involved in the definition of the identity of specific cell types in the ventral midbrain. We integrate bioinformatics and functional genomics, together with developmental neurobiology. Moreover, we propose guidelines for the computational analysis of microarray gene expression data. Our findings help to clarify some molecular aspects of the development and differentiation of DA neurons within the midbrain.
Comparison of gene expression profile in embryonic mesencephalon and neuronal primary cultures.
Specimen part, Disease
View SamplesTo identify novel Nurr1 target genes we have used microarrays strategies in rat midbrain primary cultures, enriched in dopaminergic neurons, by the action of basic fibroblast growth factor (bFGF, 20ng/ml) and Sonic hedgedog (SHH), following upregulation of Nurr1 expression by depolarization.To this aim we have treated the cultures after 9 days in vitro for 2h with high KCl and collected 30 min or 2 h after the end of depolarization (2h + 30 min or 2h + 2h). With this experimental protocol we have identify a putative Nurr1 regulator and Nurr1 target
Bdnf gene is a downstream target of Nurr1 transcription factor in rat midbrain neurons in vitro.
Specimen part
View SamplesThese cultures were grown to examine the differences in Agr-regulated virulence factor gene expression between wild-type S. aureus FRI1169 and a non-hemolytic variant isolated from a biofilm inoculated with FRI1169. The study is described more thoroughly in the paper "Generation of virulence factor variants in Staphylococcus aureus biofilms", Yarwood et al., J. Bacteriol. 2007.
Generation of virulence factor variants in Staphylococcus aureus biofilms.
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View SamplesDentatorubral-pallidoluysian Atrophy (DRPLA) is a human polyQ disease caused by the expansion of a CAG strech in the atrophin-1 (at-1) gene. In all vertebrates, a second atrophin gene (at-2) is present and it encodes a related protein void of polyQ tracks. In D.melanogaster there is one conserved Atrophin (Atro) gene, ubiquitously expressed, which contains all functional domains of vertebrate Atrophins, including two polyQ stretches. To understand to what extent transcriptional alterations cause neurodegeneration and are linked to the normal functions of Atrophin, we performed a genome wide transcriptional profiling in our Drosophila models, focusing on primary events that precede neurodegeneration.
Polyglutamine Atrophin provokes neurodegeneration in Drosophila by repressing fat.
No sample metadata fields
View SamplesLow levels of MYB promote the development of myeloproliferative neoplasm (MPN). The cell type identified that can transplant the MPN phenotype has been identified as expressing KIT, CD11b and low levels of lineage markers (K11bL).
Transcriptional regulation of SPROUTY2 by MYB influences myeloid cell proliferation and stem cell properties by enhancing responsiveness to IL-3.
Sex, Age, Specimen part
View SamplesMicrogravity as well as chronic muscle disuse are two causes of low back pain originated at least in part from paraspinal muscle deconditioning. At present no study investigated the complexity of the molecular changes in human or mouse paraspinal muscles exposed to microgravity. The aim of this study was to evaluate longissimus dorsi and tongue (as a new potential in-flight negative control) adaptation to microgravity at global gene expression level. C57BL/N6 male mice were flown aboard the BION-M1 biosatellite for 30 days (BF) or housed in a replicate flight habitat on ground (BG). . Global gene expression analysis identified 89 transcripts differentially regulated in longissimus dorsi of BF vs. BG mice (False Discovery Rrate < 0,05 and fold change < -2 and > +2), while only a small number of genes were found differentially regulated in tongue muscle ( BF vs. BG = 27 genes).
Microgravity-Induced Transcriptome Adaptation in Mouse Paraspinal <i>longissimus dorsi</i> Muscle Highlights Insulin Resistance-Linked Genes.
Specimen part
View SamplesMicrogravity exposure as well as chronic muscle disuse are two of the main causes of physiological adaptive skeletal muscle atrophy in humans and murine animals in physiological condition. The aim of this study was to investigate, at both morphological and global gene expression level, skeletal muscle adaptation to microgravity in mouse soleus and extensor digitorum longus (EDL). Adult male mice C57BL/N6 were flown aboard the BION-M1 biosatellite for 30 days on orbit (BF) or housed in a replicate flight habitat on Earth (BG) as reference flight control.
Gene Expression Profiling in Slow-Type Calf Soleus Muscle of 30 Days Space-Flown Mice.
Sex, Specimen part
View SamplesWe present a microarray analysis of primary mouse astrocytes exposed to HIV-1 in culture. Results are compared with previous genomic studies of HIV-1 effect in human astrocytes and human and macaque brains.
Gene expression profiles of HIV-1-infected glia and brain: toward better understanding of the role of astrocytes in HIV-1-associated neurocognitive disorders.
Specimen part, Treatment
View SamplesMutations altering the normal function of C/EBPa are frequent in acute myeloid leukaemia with normal karyotype. MYB, a cooperating partner of C/EBPa, is likewise heavily implicated in AML. Here we investigate how the relative requirement for the transcription factor MYB in AML relates to the particular combinations of wild type and mutated alleles of CEBPA. Through knockdown of Myb in murine cell lines modelling the spectrum of CEBPA mutations we show that the consequences of reduced Myb depend on the mutational status of Cebpa. Importantly, Myb knockdown fails to override the block in myeloid differentiation in cells with biallelic N-terminal C/EBPa mutations, demonstrating for the first time that the dependency on Myb observed in AML is much lower in leukaemia with this combination of mutations. By comparing genome-wide analyses of gene expression following Myb knockdown and ChIP-seq data for the binding of C/EBPa isoforms, we provide evidence for a functional cooperation between C/EBPa and Myb in the maintenance of the leukaemia state. This co-dependency breaks down when both alleles of CEBPA harbour N-terminal mutations, as a subset of C/EBPa-regulated genes only bind the short p30 C/EBPa isoform and, unlike other C/EBPa regulated genes, do so without a requirement for Myb. Overall design: Gene expression analysis of FMH9, KL and LL cells with and without Myb knockdown
Dependence on Myb expression is attenuated in myeloid leukaemia with N-terminal CEBPA mutations.
Subject
View SamplesMutant embryos lacking maternal and zygotic HOW exhibit defects in mesoderm development. How is an RNA binding protein that regulates the levels of mRNAs by controling RNA metabolism.
Post-transcriptional repression of the Drosophila midkine and pleiotrophin homolog miple by HOW is essential for correct mesoderm spreading.
No sample metadata fields
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