Drosophila S2 cells were treated with Heat-shock protein 90 (Hsp90) inhibitor radicicol for 15min, 30min and 1h. Poly(A) RNA was isolated and sequenced. Overall design: Kinetics of transcriptional response to Hsp90 inhibition
Hsp90 globally targets paused RNA polymerase to regulate gene expression in response to environmental stimuli.
Specimen part, Cell line, Subject, Time
View SamplesNeural precursor cells (NPCs) are multipotent cells that can generate neurons, astrocytes, and oligodendrocytes in the mammalian central nervous system. Although Zbtb20 was expressed in NPCs, its functions in neural development are not fully understood. We performed microarray analysis to examine changes in gene expression between control and Zbtb20-overexpressed NPCs.
Zbtb20 promotes astrocytogenesis during neocortical development.
Specimen part
View SamplesMagnaporthe oryzae causes rice blast, the most devastating foliar fungal disease of cultivated rice. During disease development the fungus simultaneously maintains both biotrophic and necrotrophic growth corresponding to a hemi-biotrophic life style. The ability of M. oryzae to also colonize roots and subsequently develop blast symptoms on aerial tissue has been recognized. The fungal root infection strategy and the respective host responses are currently unknown. Global temporal expression analysis suggested a purely biotrophic infection process reflected by the rapid induction of defense response-associated genes at the early stage of root invasion and subsequent repression coinciding with the onset of intracellular fungal growth. The same group of down-regulated defense genes was increasingly induced upon leaf infection by M. oryzae where symptom development occurs shortly post tissue penetration. Our molecular analysis therefore demonstrates the existence of fundamentally different tissue-specific fungal infection strategies and provides the basis for enhancing our understanding of the pathogen life style.
Tissue-adapted invasion strategies of the rice blast fungus Magnaporthe oryzae.
Specimen part
View SamplesThe Photo-Activatable Ribonucleoside-enhanced CrossLinking and ImmunoPrecipitation (PAR-CLIP) method was recently developed for global identification of RNAs interacting with proteins. The strength of this versatile method results from induction of specific T to C transitions at sites of interaction. However, current analytical tools do not distinguish between non-experimentally and experimentally induced transitions. Furthermore, geometric properties at potential binding sites are not taken into account. To surmount these shortcomings, we developed a two-step algorithm consisting of a non-parametric two-component mixture model and a wavelet-based peak calling procedure. Our algorithm can reduce the number of false positives up to 24% thereby identifying high confidence interaction sites. We successfully employed this approach in conjunction with a modified PAR-CLIP protocol to study the functional role of nuclear MOV10, a putative RNA helicase interacting with Argonaute2 and Polycomb. Our method, available as the R package wavClusteR, is generally applicable to any substitution-based inference problem in genomics. Overall design: The data comprises one MOV10 PAR-CLIP data file and one nuclear RNA-seq file
Mixture models and wavelet transforms reveal high confidence RNA-protein interaction sites in MOV10 PAR-CLIP data.
Cell line, Subject
View SamplesThe molecular chaperone heat shock protein 90 (HSP90) is thought to buffer genetic variation uncoupling phenotypic outcome from individual genotypes. HSP90 thus acts as an evolutionary capacitor by facilitating an accumulation of natural genetic variation. The molecular mechanism underlying the buffering ability is unclear, and HSP90-contingent genetic variation maps both to coding and non-coding parts of the genome. Our genome-wide data indicate that a compromised chaperoning activity of HSP90 causes derepression of endogenous retroviruses (ERVs) in mouse somatic cells. This results in an upregulation of host genes located in the neighborhood of pre-existing ERVs insertion sites. We provide genetic and biochemical evidence that HSP90 cooperates with KAP1/ SETDB1 histone methyltranferase pathway to repress ERVs. Individual mouse strains have unique integration sites of ERVs in their genomes. Consequently distinct genes are responsive to HSP90 inhibitor in different mouse strains depending on the position of the genes vis-Ã -vis strain-specific ERV insertion sites. Since ERVs have been exapted to drive novel transcriptional networks during mammalian evolution, HSP90 may have acted as a capacitor by buffering variation caused by ERV in non-coding regions of the genome. Our studies provide the first molecular framework by which HSP90 can mitigate genetic variation in gene-regulatory regions affecting gene expression and phenotypes. Overall design: We have performed RNA-seq in mouse embryonic stem cells, neuronal progenitor cells and bone-marrow-derived macrophages treated with NVP-AUY922 in triplicates.
The evolutionary capacitor HSP90 buffers the regulatory effects of mammalian endogenous retroviruses.
Specimen part, Subject
View SamplesAnalysis of sol2 mutant. SOL2 protein is a receptor-like kinase
The receptor-like kinase SOL2 mediates CLE signaling in Arabidopsis.
No sample metadata fields
View SamplesWe report RNA-sequencing data from zebrafish embryos lacking both maternal and zygotic expression of udu (which encodes Gon4l) (MZudu) at tailbud (TB) stage. Transcripts were compared to stage-matched wild-type (WT) embryos to identify differentially expressed genes. Overall design: Sequencing of polyadenylated mRNAs from MZudu mutant and control WT embryos with 2 biological and 2 technical replicates per genotype - each with 3 lanes per sample.
Gon4l regulates notochord boundary formation and cell polarity underlying axis extension by repressing adhesion genes.
No sample metadata fields
View SamplesProductive rearrangement of the immunoglobulin heavy chain locus triggers a major developmental checkpoint that promotes limited clonal expansion of pre-B cells, culminating in cell cycle arrest and rearrangement of the kappa () or lambda () light-chain loci. B lineage cells lacking the related transcription factors IRF-4 and IRF-8 undergo a developmental arrest at the cycling pre-B cell stage and are blocked for light-chain recombination. Using Irf-4,8-/- pre-B cells we demonstrate that two pathways converge to synergistically drive light-chain rearrangement, a process that is not simply activated by cell cycle exit. One pathway is directly dependent on IRF-4, whose expression is elevated by pre-BCR signaling. IRF-4 targets the 3 and enhancers to increase locus accessibility and positions a kappa allele away from pericentromeric heterochromatin. The other pathway is triggered by attenuation of IL-7 signaling and results in activation of the intronic enhancer via binding of the transcription factor, E2A. Intriguingly, IRF-4 regulates the expression of CXCR4 and promotes the migration of pre-B cells in response to the chemokine CXCL12. We propose that IRF-4 coordinates the two pathways regulating light-chain recombination by positioning pre-B cells away from IL-7 expressing stromal cells.
Regulation of immunoglobulin light-chain recombination by the transcription factor IRF-4 and the attenuation of interleukin-7 signaling.
No sample metadata fields
View SamplesPlasmacytoid dendritic cells (pDCs) rapidly produce type I interferon (IFN-I) in response to viruses and are essential for antiviral immune responses. Although related to classical dendritic cells (cDCs) in their development and expression profile, pDCs possess many distinct features. Unlike cDCs, pDCs develop in the bone marrow (BM) and emerge into peripheral lymphoid organs and tissues as fully differentiated cells. We now report that pDCs specifically express Runx2, a Runt family transcription factor that is essential for bone development. Runx2-deficient murine pDCs developed normally in the BM but were greatly reduced in the periphery. The defect was cell-intrinsic and was associated with the retention of mature Ly49Q+ pDCs in the BM. Runx2 was required for the expression of several pDC-enriched genes including chemokine receptors Ccr2 and Ccr5. Mature pDCs expressed high levels of Ccr5 at the surface, and Ccr5-deficient pDCs in a competitive setting were reduced in the periphery relative to the BM. Thus, Runx2 is required for the emergence of mature BM pDCs into the periphery, in a process that is partially dependent on Ccr5. These results establish Runx2 as a lineage-specific regulator of immune system development.
Transcription factor Runx2 controls the development and migration of plasmacytoid dendritic cells.
Specimen part
View SamplesOver the last decade, small noncoding RNA molecules such as microRNAs (miRNAs) have emerged as critical regulators in the expression and function of eukaryotic genomes. It has been suggested that viral infections and neurological disease outcome may also be shaped by the influence of small RNAs. This has prompted us to suggest that HIV infection alters the endogenous miRNA expression patterns, thereby contributing to neuronal deregulation and AIDS dementia. Therefore, using primary cultures and neuronal cell lines, we examined the impact of a viral protein (HIV-1 Tat) on the expression of miRNAs due to its characteristic features such as release from the infected cells and taken up by noninfected cells. Using microRNA array assay, we demonstrated that Tat deregulates the levels of several miRNAs. Interestingly, miR-34a was among the most highly induced miRNAs in Tat-treated neurons. Tat also decreases the levels of miR-34a target genes such as CREB protein as shown by real time PCR. The effect of Tat was neutralized in the presence of anti-miR-34a. Using in situ hybridization assay, we found that the levels of miR-34a increase in Tat transgenic mice when compared with the parental mice. Therefore, we conclude that deregulation of neuronal functions by HIV-1 Tat protein is miRNA-dependent.
HIV-1 Tat protein promotes neuronal dysfunction through disruption of microRNAs.
Specimen part, Cell line, Treatment
View Samples