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GSE10023
Zea mays
39 Downloadable Samples
Affymetrix Maize Genome Array (maize)
Description
The fungal pathogen Ustilago maydis establishes a biotrophic relationship with its host plant maize. Hallmarks of the disease are large plant tumors in which fungal proliferation occurs. Plants have developed various defense pathways to cope with pathogens. We used microarrays to detail the global programme of gene expression during the infection process of Ustilago maydis in its host plant to get insights into the defense programs and the metabolic reprogramming needed to supply the fungus with nutrients.
Publication Title
Ustilago maydis infection strongly alters organic nitrogen allocation in maize and stimulates productivity of systemic source leaves.
Sample Metadata Fields
Specimen part
View Samples- Zea mays
- 9 Downloadable Samples
- Affymetrix Maize Genome Array (maize)
Description
Ustilago maydis is a plant-pathogenic fungus that establishes a biotrophic relationship with its host Zea mays. The biotrophic interaction is initiated upon host penetration, and involves expansion of the host plasma membrane around hyphae, which is thought to facilitate the exchange of nutrients and virulence factors. Transcriptional regulators involved in the establishment of an infectious dikaryon and penetration into the host have been identified, however, regulators involved in the post-penetration stages remained to be elucidated. In the study we report the identification of an Ustilago maydis forkhead transcription factor, Fox1, which is exclusively expressed during biotrophic development. Deletion of fox1 results in reduced virulence and impaired tumour development in planta. fox1 hyphae induce plant defences including the overproduction and accumulation of H2O2 in and around infected cells. This oxidative burst acts as an intercellular signal, which elicits a specific host defence response phenotypically represented by the encasement of proliferating hyphae in extensions of the plant cell wall. Maize microarrays experiments were performed to identify genes involved in the observed plant defence responses on leaf tissue infected with U. maydis strain SG200fox1 4 dpi.
Publication Title
The Ustilago maydis forkhead transcription factor Fox1 is involved in the regulation of genes required for the attenuation of plant defenses during pathogenic development.
Sample Metadata Fields
Specimen part
View Samples- Pseudomonas aeruginosa
- 4 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
In this experiment the transcriptional profile of the Pseudomonas aeruginosa PA14 two-component sensor kinase PA4398 was investigated under swarming conditions using DNA microarrays. To this aim three independent cultures of the PA14 wild-type and the PA4398 mutant were grown until mid-log phase in Luria-Bertani broth following an incubation on BM2-swarm plates containing 0.1 % (wt/vol) casaminoacids and 0.5 % (wt/vol) agar for 20 h at 37 °C. Subsequent total RNA was extracted from the leading edge of dendritic swarm colonies and analyzed by microarrays.
Publication Title
No associated publication
Sample Metadata Fields
No sample metadata fields
View Samples- Pseudomonas aeruginosa
- 4 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
In this experiment the transcriptional response of the opportunistic human pathogen Pseudomonas aeruginosa towards physiological concentrations of the major human host defense peptide LL-37 was investigated using microarrays. To this aim, three independent cultures of P. aeruginosa PAO1 were grown until mid-log phase in Mueller-Hinton broth and subsequently incubated with either sublethal LL-37 concencentrations (20 µg/ml) or without peptide for 2 h at 37 °C following RNA extraction and microarray analysis.
Publication Title
No associated publication
Sample Metadata Fields
Compound
View Samples- Pseudomonas aeruginosa pao1
- 4 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
In this experiment the transcriptional response of the opportunistic human pathogen Pseudomonas aeruginosa to sublethal concentrations of NaClO was investigated. To this aim, four independent cultures of P. aeruginosa PAO1 grown in minimal medium BM2 were treated with NaClO (2 ug/ml) for 1 h at 37 C followed by RNA extraction and microarray analysis. Untreated cultures served as controls.
Publication Title
No associated publication
Sample Metadata Fields
Compound
View Samples- Mus musculus
- 77 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
L-3,4-dihydroxyphenylalanine (levodopa) treatment is the major pharmacotherapy for Parkinson's disease. However, almost all patients receiving levodopa eventually develop debilitating involuntary movements (dyskinesia). While it is known that striatal spiny projection neurons (SPNs) are involved in the genesis of this movement disorder, the molecular basis of dyskinesia is not understood. In this study, we identify distinct cell-type-specific gene expression changes that occur in sub-classes of SPNs upon induction of a parkinsonian lesion followed by chronic levodopa treatment. We identify several hundred genes whose expression is correlated with levodopa dose, many of which are under the control of AP-1 and ERK signaling. In spite of homeostatic adaptations involving several signaling modulators, AP-1-dependent gene expression remains highly dysregulated in direct pathway SPNs (dSPNs) upon chronic levodopa treatment. We also discuss which molecular pathways are most likely to dampen abnormal dopaminoceptive signaling in spiny projection neurons, hence providing potential targets for antidyskinetic treatments in Parkinson's disease.
Publication Title
Molecular adaptations of striatal spiny projection neurons during levodopa-induced dyskinesia.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 41 Downloadable Samples
- Illumina HumanHT-12 V3.0 expression beadchip
Description
This study explores the impact of lifestyle and environment on gene expression through whole transcriptome profiling of peripheral blood samples in Fijian population (native Melanesians and Indians) living in the rural and urban areas.
Publication Title
Using blood informative transcripts in geographical genomics: impact of lifestyle on gene expression in fijians.
Sample Metadata Fields
Sex, Age, Specimen part, Subject
View Samples- Mus musculus
- 32 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Ebf1 is a transcription factor with documented, and dose dependent, functions in both normal and malignant B-lymphocyte development. In order to understand more about the role of Ebf1 in malignant transformation, we have investigated the impact of reduced functional Ebf1 dose on early B-cell progenitors. Gene expression analysis in loss and gain of function analysis suggested that Ebf1 was involved in the regulation of genes of importance for DNA repair as well as cell survival. Investigation of the level of DNA damage in steady state as well as after induction of DNA damage by UV light supported that pro-B cells lacking one functional allele of Ebf1 display a reduced ability to repair DNA damage. This was correlated to a reduction in expression of Rad51 and combined analysis of published 4C and chromatin Immuno precipitation data suggested that this gene is a direct target for Ebf1. Even though the lack of one allele of Ebf1 did not result in any dramatic increase of tumor formation, we noted a dramatic increase in the formation of pro-B cell leukemia in mice carrying a combined heterozygote mutation in the Ebf1 and Pax5 genes. Even though the tumors were phenotypically similar and stable, we noted a large degree of molecular heterogeneity well in line with a mechanism involving impaired DNA repair. Our data support the idea that Ebf1 controls homologous DNA repair in a dose dependent manner and that this may explain the frequent involvement of Ebf1 in human leukemia
Publication Title
Ebf1 heterozygosity results in increased DNA damage in pro-B cells and their synergistic transformation by Pax5 haploinsufficiency.
Sample Metadata Fields
Specimen part, Cell line, Time
View Samples- Homo sapiens
- 27 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Samples of primary tumors collected from 23 ovarian cancer patients
Publication Title
Machine learning predicts individual cancer patient responses to therapeutic drugs with high accuracy.
Sample Metadata Fields
Sex, Specimen part, Disease
View Samples- Homo sapiens
- 28 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
MicroRNAs (miRNAs) are short (~22 nucleotides) regulatory RNAs that can modulate gene expression and are aberrantly expressed in many diseases including cancer. Previous studies have shown that miRNAs inhibit the translation and facilitate the degradation of their targeted mRNAs making them attractive candidates for use in cancer therapy. However, the potential clinical utility of miRNAs in cancer therapy rests heavily upon our ability to understand and accurately predict the consequences of fluctuations in levels of miRNAs within the context of complex tumor cells. To evaluate the predictive power of current models, levels of miRNAs and their targeted messenger RNAs (mRNAs) were measured in laser captured micro-dissected (LCM) ovarian cancer epithelial cells (CEPI) and compared with levels present in ovarian surface epithelial cells (OSE). We found that the predicted inverse correlation between changes in levels of miRNAs and levels of their mRNA targets held for only ~6-11% of predicted target mRNAs. Our results underscore the complexities of miRNA-mediated regulation in vivo and caution against the widespread clinical application of miRNAs and miRNA inhibitors until the basis of these complexities is more fully understood.
Publication Title
Evidence for the complexity of microRNA-mediated regulation in ovarian cancer: a systems approach.
Sample Metadata Fields
Cell line
View Samples