Transcription and pre-mRNA alternative splicing are highly regulated processes that play major roles in modulating eukaryotic gene expression. It is increasingly apparent that other pathways of RNA metabolism, including small RNA biogenesis, can regulate these processes. However, a direct link between alternative pre- mRNA splicing and small RNA pathways has remained elusive. Here we show that the small RNA pathway protein Argonaute-2 (Ago-2) regulates alternative pre-mRNA splicing patterns of specific transcripts in the Drosophila nucleus using genome-wide methods in conjunction with RNAi in cell culture and Ago-2 deletion or catalytic site mutations in Drosophila adults. Moreover, we show that nuclear Argonaute-2 binds to specific chromatin sites near gene promoters and negatively regulates the transcription of the Ago-2-associated target genes. These transcriptional target genes are also bound by Polycomb group (PcG) transcriptional repressor proteins and change during development, implying that Ago-2 may regulate Drosophila development. Impor- tantly, both of these activities were independent of the catalytic activity of Ago-2, suggesting new roles for Ago-2 in the nucleus. Finally, we determined the nuclear RNA-binding profile of Ago-2, found it bound to several splicing target transcripts, and identified a G-rich RNA-binding site for Ago-2 that was enriched in these transcripts. These results suggest two new nuclear roles for Ago-2: one in pre-mRNA splicing and one in transcriptional repression. Overall design: 2 Ago2 mutants, 51B and V966M, heterozygotes and homozygotes of both each sequenced in duplicate
Two new and distinct roles for Drosophila Argonaute-2 in the nucleus: alternative pre-mRNA splicing and transcriptional repression.
Sex, Subject
View SamplesThe aim of this experiment was to investigate differential gene expression in splenocytes stimulated with BCG from nave and BCG vaccinated mice. The differences between nave and BCG vaccinated mice might indicate the mechanisms by which BCG vaccination confers an enhanced ability of splenocytes from BCG vaccinated mice to inhibit growth of BCG in splenocyte cultures as compared with splenocytes from naive animals.
Mycobacterial growth inhibition in murine splenocytes as a surrogate for protection against Mycobacterium tuberculosis (M. tb).
Sex, Age, Specimen part
View SamplesTransient expression of two factors, or from Oct4 alone, resulted in efficient generation of human iPSCs. The reprogramming strategy described revealed a potential transcriptional signature for human iPSCs yet retaining the gene expression of donor cells in human reprogrammed cells free of viral and transgene interference.
Transcriptional signature and memory retention of human-induced pluripotent stem cells.
Sex, Specimen part
View SamplesHuman medulloblastoma (MB) can be segregated into four major categories based on gene expression patterns: Hedgehog (HH) subtype, Wnt subtype, Group 3, and Group 4. However, they all exhibit strikingly different gene expression profiles from Atypical Teratoid/Rhabdoid Tumor (AT/RT). We re-analyzed published gene expression microarray dataset of pediatric brain tumors to identify a gene expression profile that clearly distinguished human AT/RT from human MB. We used this profile, choosing only genes that have clear murine orthologs, to compare tumors from Snf5F/Fp53L/LGFAP-Cre mice (in C57Bl/6 strain background) with MB from Ptc1+/- mice (in mixed C57Bl/6 and 129Sv strain background). Snf5F/Fp53L/LGFAP-Cre tumors are clearly very different from mouse MB and the markers that distinguish human AT/RT from human MB also distinguish the mouse tumors.
Generation of a mouse model of atypical teratoid/rhabdoid tumor of the central nervous system through combined deletion of Snf5 and p53.
No sample metadata fields
View SamplesFour vehicle-treated and four HhAntag-treated pancreatic xenograft tumors were profiled for gene expression changes using Affymetrix U133 Plus 2.0 and Affymetrix Mouse Genome 430 2.0 arrays.
A paracrine requirement for hedgehog signalling in cancer.
No sample metadata fields
View SamplesAbout 10% of all NSCLC patients respond to gefitnib treatment and all of these patients will acquire resistance to the EGFR TKI.
Rapidly acquired resistance to EGFR tyrosine kinase inhibitors in NSCLC cell lines through de-repression of FGFR2 and FGFR3 expression.
Cell line, Treatment
View SamplesPeripherally derived macrophages infiltrate the brain after bone marrow transplantation and during central nervous system (CNS) inflammation. It was initially suggested that these engrafting cells were newly derived microglia and that irradiation was essential for engraftment to occur. However, it remains unclear whether brain-engrafting macrophages (beMfs) acquire a unique phenotype in the brain, whether long-term engraftment may occur without irradiation, and whether brain function is affected by the engrafted cells. In this study, we demonstrate that chronic, partial microglia depletion is sufficient for beMfs to populate the niche and that the presence of beMfs does not alter behavior. Furthermore, beMfs maintain a unique functional and transcriptional identity as compared with microglia. Overall, this study establishes beMfs as a unique CNS cell type and demonstrates that therapeutic engraftment of beMfs may be possible with irradiation-free conditioning regimens. Overall design: Microglia were isolated from the brains of adult male c57BL/6 mice given bone marrow tranplants (BMT) with or without head shield. All mice received PLX5622 for 2 weeks, then placed and normal chow to recoever. Some mice were then challenged with LPS. Cells were isolated by MACS using CD11b magnetic beads.
Peripherally derived macrophages can engraft the brain independent of irradiation and maintain an identity distinct from microglia.
Age, Specimen part, Cell line, Treatment, Subject
View SamplesPeripherally derived macrophages infiltrate the brain after bone marrow transplantation and during central nervous system (CNS) inflammation. It was initially suggested that these engrafting cells were newly derived microglia and that irradiation was essential for engraftment to occur. However, it remains unclear whether brain-engrafting macrophages (beMfs) acquire a unique phenotype in the brain, whether long-term engraftment may occur without irradiation, and whether brain function is affected by the engrafted cells. In this study, we demonstrate that chronic, partial microglia depletion is sufficient for beMfs to populate the niche and that the presence of beMfs does not alter behavior. Furthermore, beMfs maintain a unique functional and transcriptional identity as compared with microglia. Overall, this study establishes beMfs as a unique CNS cell type and demonstrates that therapeutic engraftment of beMfs may be possible with irradiation-free conditioning regimens. Overall design: Mice were given 1000rad whole body irradiation, followed by bone marrow transplant with UBC-GFP bone marrow at 8 weeks of age. Engraftment was allowed to occur for 8 months, then engrafting macrophages and microglia were isolated from whole brains for RNA-Seq.
Peripherally derived macrophages can engraft the brain independent of irradiation and maintain an identity distinct from microglia.
Age, Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A Long Noncoding RNA Regulates Sister Chromatid Cohesion.
Cell line
View SamplesLong noncoding RNAs (lncRNAs) have appeared to be involved in the most diverse cellular processes through multiple mechanisms. Here we describe a previously uncharacterized human lncRNA, CONCR (cohesion regulator noncoding RNA), transcriptionally activated by MYC, which is upregulated in multiple cancer types. The expression of CONCR is cell cycle-regulated, and it is required for cell cycle progression and DNA replication. Moreover, cells depleted of CONCR show severe defects in sister chromatid cohesion, suggesting an essential role for CONCR in cohesion establishment during cell division. CONCR interacts with and regulates the activity of DDX11, a DNA-dependent ATPase and helicase involved in DNA replication. These findings suggest a novel mechanism of action for CONCR in the modulation of DDX11 enzymatic activity, unveiling the direct involvement of a lncRNA in the establishment of sister chromatid cohesion.
A Long Noncoding RNA Regulates Sister Chromatid Cohesion.
Cell line
View Samples