A high-resolution time series study of transcriptome dynamics following antimiR--mediated inhibition of miR-9 in a Hodgkin lymphoma cell-line revealed both general and miR-9 specific aspects of the miRNA--mediated post--transcriptional dynamic response.MiR-9 inhibition induced a multiphasic gene response, with an initial direct response at approximately 4 hours and multiple later responses which showed transcription factor enrichments indicative of indirect causally downstream responses, and an overall shift of gene product function from predominantly mRNA processing at early time points to translation at later time points.
Transcriptome dynamics of the microRNA inhibition response.
Cell line, Treatment, Time
View SamplesThe main cell of origin of the Sonic hedgehog (SHH) subgroup of medulloblastoma (MB) is granule cell precursors (GCPs), a SHH-dependent transient amplifying population in the developing cerebellum. SHH-MBs can be further subdivided based on molecular and clinical parameters, as well as location since SHH-MBs occur preferentially in the lateral cerebellum (hemispheres). Our analysis of adult patient data suggests that tumors with Smoothened (SMO) mutations form more specifically in the hemispheres than those with Patched 1 (PTCH1) mutations. Using sporadic mouse models of SHH-MB with the two mutations commonly seen in adult MB, constitutive activation of Smo (SmoM2) or loss-of-Ptch1, we found that regardless of timing of induction or type of mutation, tumors developed primarily in the hemispheres with SmoM2-mutants indeed showing a stronger specificity. We further uncovered that GCPs in the hemispheres are more susceptible to high level SHH signaling compared to GCPs in the medial cerebellum (vermis), as more SmoM2 or Ptch1-mutant hemisphere cells remain undifferentiated and show increased tumorigenicity when transplanted. Finally, we identified location-specific GCP gene expression profiles, and found that deletion of the genes most highly expressed in the hemispheres (Nr2f2) or vermis (Engrailed1) showed opposing effects on GCP differentiation. Our studies thus provide new insights into intrinsic differences within GCPs that impact on SHH-MB progression.
Lateral cerebellum is preferentially sensitive to high sonic hedgehog signaling and medulloblastoma formation.
Specimen part
View SamplesWe identified miR-95 in a screen for miRNAs which functionally affect
A non-conserved miRNA regulates lysosomal function and impacts on a human lysosomal storage disorder.
Cell line
View SamplesPiwi-interacting RNAs (piRNAs) are ~24-30 nucleotide regulatory RNAs that are abundantly expressed in gonads. The most well-understood piRNAs mediate post-transcriptional defense against transposable elements (TEs), and derive from sense or antisense strands as a consequence of "ping-pong" amplification of complementary sequences of active TEs and piRNA master control transcripts. Another class of piRNAs, such as those expressed in pachytene testis, derive from large intergenic clusters that are strictly single-stranded. Here, we report a third substrate that generates abundant primary piRNAs. In somatic follicle cells of Drosophila ovaries, we cloned >1 million piRNAs from thousands of messenger RNAs, and these were quite preferentially derived from 3' untranslated regions. This segregation implies a competition between the translation machinery and primary piRNA biogenesis machinery for mRNA access.
No associated publication
Specimen part, Cell line
View SamplesCis-natural antisense transcripts (cis-NATs) have been speculated to be substrates for endogenous RNA interference (RNAi), but little experimental evidence for such a pathway in animals has been reported. Analysis of massive Drosophila melanogaster small RNA data sets now reveals that endogenous small interfering RNAs (siRNAs) are produced via bidirectional transcription. >100 cis-NATs with overlapping 3' exons generate 21-nt, Dicer-2 (Dcr-2)dependent, 3'-end modified siRNAs.
No associated publication
No sample metadata fields
View SamplesExpression profiling of a panel of 101 adult male germ cell tumors and 5 normal testis specimens was performed on Affymetrix U133A and U133B microarrays. This data has been used to:
Down-regulation of stem cell genes, including those in a 200-kb gene cluster at 12p13.31, is associated with in vivo differentiation of human male germ cell tumors.
No sample metadata fields
View SamplesThis series represents expression profiles of 34 non-seminoma germ cell tumors (NSGCTs) from patients who received cisplatin based chemotherarpy for treatment of their disease for whom full clinical follow-up information was available. These specimens were used as a validation set to test outcome prediction models using a subset of previously profiled GCT specimens (see GEO accession #GSE3218).
Identification and validation of a gene expression signature that predicts outcome in adult men with germ cell tumors.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Dissecting the unique role of the retinoblastoma tumor suppressor during cellular senescence.
Cell line
View SamplesThe action of RB as a tumor suppressor has been difficult to define, in part, due to the redundancy of the related proteins p107 and p130. By coupling advanced RNAi technology to suppress RB, p107 or p130 with a genome wide analysis of gene expression in growing, quiescent or ras-senescent cells, we identified a unique and specific activity of RB in repressing DNA replication as cells exit the cell cycle into senescence, a tumor suppressive program.
Dissecting the unique role of the retinoblastoma tumor suppressor during cellular senescence.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
H3K4 demethylation by Jarid1a and Jarid1b contributes to retinoblastoma-mediated gene silencing during cellular senescence.
Specimen part, Cell line
View Samples