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Drosophila melanogaster
3 Downloadable Samples
Illumina HiSeq 2000
Description
Although small RNAs efficiently control transposition activity of most transposons in the host genome, such immune system is not always applicable against new transposon's invasions. Here we explored a possibility to introduce potentially mobile copy of the Penelope retroelement previously implicated in hybrid dysgenesis syndrome in Drosophila virilis into the genomes of two distant Drosophila species. The consequences of such introduction were monitored at different phases after experimental colonization as well as in D. virilis species which is apparently in the process of ongoing Penelope invasion. We investigated the expression of Penelope and biogenesis of Penelope-derived small RNAs in D. virilis and D. melanogaster strains originally lacking active copies of this element after experimental Penelope invasion. These strains were transformed by constructs containing intact Penelope copies. We show that immediately after transformation, which imitates the first stage of retroelement invasion, Penelope undergoes transposition predominantly in somatic tissues, and may produce siRNAs that are apparently unable to completely silence its activity. However, at the later stages of colonization Penelope copies may jump into one of the piRNA-clusters, which results in production of homologous piRNAs that are maternally deposited and can silence euchromatic transcriptionally active copies of Penelope in trans and, hence, prevent further amplification of the invader in the host genome. Intact Penelope copies and different classes of Penelope-derived small RNAs were found in most geographical strains of D. virilis collected throughout the world. Importantly, all strains of this species containing full-length Penelope tested do not produce gonadal sterility in dysgenic crosses and, hence, exhibit neutral cytotype. In order to understand whether RNA interference mechanism able to target Penelope operates in related species of the virilis group we correlated the presence of full-length and potentially active Penelope with the occurrence of piRNAs homologous to this TE in the ovaries of species comprising the group. It was demonstrated, that Penelope-derived piRNAs are present in all virilis group species containing full-length but transcriptionally silent copies of this element that probably represent the remnants of its previous invasions taking place in the course of the virilis species divergent evolution. Overall design: piRNA size profile (23-29nt) was examined in D. melanogaster strains, where Penelope-piRNAs are detected by Northern blot
Publication Title
Evolution and dynamics of small RNA response to a retroelement invasion in Drosophila.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Homo sapiens
- 15 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Muscle biopsies from biceps and deltoid were taken from 5 patients with FSHD, 5 asymptomatic carriers and 5 normal controls. The genome-wide expression patterns were compared using Affymetrix U133 Plus 2.0 chips.
Publication Title
Transcriptional regulation differs in affected facioscapulohumeral muscular dystrophy patients compared to asymptomatic related carriers.
Sample Metadata Fields
Sex, Age, Specimen part, Disease
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Objective: Analyze expression patterns of genes located at linkage region of SPOAN syndrome (11q12-13), in order to identify genes differentially expressed in samples of SPOAN individuals compared to healthy controls.
Publication Title
Overexpression of KLC2 due to a homozygous deletion in the non-coding region causes SPOAN syndrome.
Sample Metadata Fields
Specimen part
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GSE10258- Homo sapiens
- 15 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
AML/MDS patients carrying 11q amplifications involving the mixed lineage leukemia gene (MLL) locus are characterized by a later onset, a complex aberrant karyotype (CAK) frequently including deletions within 5q, 17p and 7q, as well as fast progression of the disease with extremely poor prognosis. We and other have shown that the MLL gene is over expressed in amplified cases, however, in most of the cases the amplified region is not restricted to the MLL locus. In the present study we investigated 19 patients with AML/MDS and MLL gain/amplification [15 AML (two secondary, following MDS and PV, and three therapy related) and 4 MDS cases (two therapy related)]. By means of array CGH performed in 12 patients (GSE9928) we were able to delineate the minimal deleted regions within 5q, 17p and 7q and identified three independent regions 11q/I-III that were amplified in all cases. Gene expression profiles established in 15 cases were used to define the candidate genes within these regions. Interestingly, analysis of our data suggests an interdependency of genes influenced by losses of 5q and 17p and expression of genes present in 11q23-25. Additionally, we demonstrate that the gene expression signature can be used to discriminate AML/MDS with MLL amplification from all other types of AML, thus, indicating specific pathogenesis present in this entity.
Publication Title
AML/MDS with 11q/MLL amplification show characteristic gene expression signature and interplay of DNA copy number changes.
Sample Metadata Fields
Sex, Age, Specimen part, Disease
View Samples- Homo sapiens
- 6 Downloadable Samples
- Illumina HiSeq 4000
Description
Connections between RNA polymerase II (RNAPII) transcription stress, R-loops, and genome instability have been established however, the underlying mechanisms remain poorly understood. Here we used a mutant version of elongation factor TFIIS (TFIISmut) to specifically induce increased levels of RNAPII pausing, arrest, and/or backtracking in human cells. TFIISmut expression results in slower elongation rates, relative depletion of polymerases from the end of genes, and increased levels of stopped RNAPII. It affects mRNA splicing and termination as well. Remarkably, however, TFIISmut expression also dramatically increases R-loops, which may form at the anterior end of backtracked RNAPII and trigger genome instability, including DNA strand breaks. These results shed new light on the relationship between transcription stress and R-loops, and suggest that different classes of R-loops exist, potentially with distinct consequences for genome instability. Overall design: To study RNAPII backtracking and its effects in human cells, we used HEK293 TREX cells in which we overexpressed, under the control of a dox-promoter, a dominant negative form of TFIIS (TFIIS mut), an elongation factor necessary for stimulating RNAPII intrinsic cleavage activity. TFIISmut cells were maintained in the presence of Dox to ensure over-expression for 48 hours prior to harvest..
Publication Title
Elongation Factor TFIIS Prevents Transcription Stress and R-Loop Accumulation to Maintain Genome Stability.
Sample Metadata Fields
Cell line, Treatment, Subject
View Samples- Homo sapiens
- 6 Downloadable Samples
- Illumina HiSeq 1500
Description
Purpose: The goal of this study is to investigate the role of CBS enzyme in colorectal carcinogenesis Methods: RNA-Seq transcriptome analysis of CBS-overexpression in NCM356 cels compared to control vector cells Overall design: RNA-seq transcriptome profiling of NCM356-CBS overexpressing cells vs. vector cells
Publication Title
Upregulation of Cystathionine-β-Synthase in Colonic Epithelia Reprograms Metabolism and Promotes Carcinogenesis.
Sample Metadata Fields
Subject
View Samples- Homo sapiens
- 38 Downloadable Samples
- Illumina Genome Analyzer IIx
Description
MiRNAs are discussed as diagnostic and therapeutic molecules. However, effective miRNA drug treatments with miRNAs are so far hampered by the complexity of the miRNA networks. To identify potential miRNA drugs in colorectal cancer, we profiled miRNA and mRNA expression in matching normal, tumor and metastasis tissues of eight patients by Illumina sequencing. We identified miRNA-1 as top candidate differentially expressed in tumor and metastasis. Furthermore, miRNA-1 was de-regulated in 16 additional tumor entities underscoring its central role in tumor pathogenesis. Functional analyses showed an additive effect of miRNA-1 with camptothecin treatment. We used a systems-biology simulation of cellular cancer models implemented in PyBios to investigate miRNA-1 function and assessed the effects of depletion as well as overexpression in terms of miRNA-1 as a potential treatment option. In this system miRNA-1 treatment reverted the disease phenotype with different effectiveness among the patients. Scoring the gene expression changes obtained through mRNA-Seq from the same patients we show that the combination of deep sequencing and systems biological modeling can help to identify patient-specific responses to miRNA treatments. We present this data as guideline for future pre-clinical assessments of new and personalized therapeutic options. Overall design: Examination of miRNA expression values by Illumina sequencing of matched benign, tumor and metastasis tissues of 8 colorectal cancer patients. For 4 of these patients all tissues have been resequenced to obtain mRNA expression values.
Publication Title
High-throughput miRNA and mRNA sequencing of paired colorectal normal, tumor and metastasis tissues and bioinformatic modeling of miRNA-1 therapeutic applications.
Sample Metadata Fields
Sex, Age, Specimen part, Disease, Disease stage, Subject
View Samples