RNase Y of Bacillus subtilis is a key member of the degradosome and important for bulk mRNA turnover. In contrast to B. subtilis, the RNase Y homologue (rny/cvfA) of Staphylococcus aureus is not essential for growth. Here we found that RNase Y plays a major role in virulence gene regulation. Accordingly, rny deletion mutants demonstrated impaired virulence in a murine bacteraemia model. RNase Y is important for the processing and stabilisation of the immature transcript of the global virulence regulator system SaePQRS. Moreover, RNase Y is involved in the activation of virulence gene expression at the promoter level. This control is independent of both the virulence regulator agr and the saePQRS processing and may be mediated by small RNAs some of which were shown to be degraded by RNase Y. Besides this regulatory effect, mRNA levels of several operons were significantly increased in the rny mutant and the half-life of one of these operons was shown to be extremely extended. However, the half-life of many mRNA species was not significantly altered. Thus, RNase Y in S. aureus influences mRNA expression in a tightly controlled regulatory manner and is essential for coordinated activation of virulence genes.
RNase Y of Staphylococcus aureus and its role in the activation of virulence genes.
No sample metadata fields
View SamplesWe investigated the association between subgingival bacterial profiles and gene expression patterns in gingival tissues of patients with periodontitis.
Subgingival bacterial colonization profiles correlate with gingival tissue gene expression.
Specimen part
View SamplesWe examined gene expression signatures in healthy and diseased gingival tissues in 90 patients. Analysis of the gingival tissue transcriptome in states of periodontal health and disease may reveal novel insights of the pathobiology of periodontitis.
Transcriptomes in healthy and diseased gingival tissues.
Specimen part
View SamplesThe goal of the microarray experiment was to do a head-to-head comparison of the U1 Adaptor technology with siRNA in terms of specificity at the genome-wide level. U1 Adaptors represent a novel gene silencing method that employs a mechanism of action distinct from antisense and RNA interference (RNAi). The U1 Adaptor is a bifunctional oligonucleotide having a Target Domain that is complementary to a site in the target gene's terminal exon and a U1 Domain that binds to the U1 small nuclear RNA (snRNA) component of the U1 small nuclear ribonucleoprotein (U1 snRNP) splicing factor. Tethering of U1 snRNP to the target pre-mRNA inhibits 3' end processing (i.e., polyA tail addition) leading to degradation of that RNA species within the nucleus thereby reducing mRNA levels. We demonstrate that U1 Adaptors can specifically inhibit both reporter and endogenous genes. Further, targeting the same gene either with multiple U1 Adaptors or with U1 Adaptors and small interfering RNAs (siRNAs), strongly enhances gene silencing, the latter as predicted from their distinct mechanisms of action. Such combinatorial targeting requires lower amounts of oligonucleotides to achieve potent silencing.
Gene silencing by synthetic U1 adaptors.
No sample metadata fields
View SamplesObjective
A subset of metastatic pancreatic ductal adenocarcinomas depends quantitatively on oncogenic Kras/Mek/Erk-induced hyperactive mTOR signalling.
No sample metadata fields
View SamplesThe objective of this study was the assessment of transcriptional dysregulation in particular with regard to B-cell differentiation factors. Most studies focus on cross-section analyses of various leukemia subtypes to identify differentially regulated genes lacking suitable reference models. Here we applied comparative intraindividual transcriptome analysis of B-precursor ALL of childhood, which introduces a side-by-side analysis of leukemic cells and matched normal lymphoblasts from the same individual in complete continuous remission after the end of re-induction therapy. This approach reduces noise by eliminating interindividual variability.
Aberrant ZNF423 impedes B cell differentiation and is linked to adverse outcome of ETV6-RUNX1 negative B precursor acute lymphoblastic leukemia.
Specimen part, Subject
View SamplesProduction of functional proteins requires multiple steps including gene transcription and post-translational processing. MicroRNAs (miRNA) can regulate individual stages of these processes. Despite the importance of the cystic fibrosis transmembrane conductance regulator (CFTR) channel for epithelial anion transport, how its expression is regulated remains uncertain. We discovered that microRNA-138 regulates CFTR expression through its interactions with the transcriptional regulatory protein SIN3A. Treating airway epithelia with a miR-138 mimic increased CFTR mRNA and also enhanced CFTR abundance and transepithelial Cl- permeability independently of elevated mRNA levels. A miR-138 anti-miR had the opposite effects. Importantly, miR-138 altered the expression of many genes encoding proteins that associate with CFTR and may influence its biosynthesis. The most common CFTR mutation, F508, causes protein misfolding, degradation, and cystic fibrosis. Remarkably, manipulating the miR-138 regulatory network also improved biosynthesis of CFTR-F508 and restored Cl- transport to cystic fibrosis airway epithelia. This novel miRNA-regulated network directs gene expression from the chromosome to the cell membrane, indicating that an individual miRNA can control a cellular process broader than previously recognized. This discovery also provides new therapeutic avenues for restoring CFTR function to cells affected by the most common cystic fibrosis mutation.
A microRNA network regulates expression and biosynthesis of wild-type and DeltaF508 mutant cystic fibrosis transmembrane conductance regulator.
Specimen part, Cell line
View SamplesInterferon gamma treatment of macrophages results in hundreds if not thousands of alterations in gene expression and an antiviral state being established in these cells. Little is known about relationship between transcript synthesis, abundance and decay in macrophages during the first hours after interferon gamma treatment and how these factors influence the antiviral cellular phenotype.
An Interferon Regulated MicroRNA Provides Broad Cell-Intrinsic Antiviral Immunity through Multihit Host-Directed Targeting of the Sterol Pathway.
Age, Specimen part
View Samplesgamma delta intraepithelial lymphocytes were isolated from the colons of DSS-treated and untreated mice. Total RNAs were isolated and compared by Affymetrix DNA microarray.
Reciprocal interactions between commensal bacteria and gamma delta intraepithelial lymphocytes during mucosal injury.
No sample metadata fields
View SamplesThe adult pancreas is capable of limited regeneration after injury, but has no defined stem cell population. The cell types and molecular signals that govern the production of new pancreatic tissue are not well understood. Here we show that inactivation of the SCF-type E3 ubiquitin ligase substrate recognition component Fbw7 induces pancreatic ductal cells to reprogram into -cells. The induced -cells resemble islet -cells in morphology and histology, express genes essential for -cell function, and release insulin upon glucose challenge. Thus, loss of Fbw7 appears to reawaken an endocrine developmental differentiation program in adult pancreatic ductal cells. Our study highlights the plasticity of seemingly differentiated adult cells, identifies Fbw7 as a master regulator of cell fate decisions in the pancreas, and reveals adult pancreatic duct cells as a latent multipotent cell type.
Loss of Fbw7 reprograms adult pancreatic ductal cells into α, δ, and β cells.
Specimen part, Treatment
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