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SRP035281
Caenorhabditis elegans
33 Downloadable Samples
Illumina Genome Analyzer II, Illumina HiSeq 2000
Description
In animals, piRNAs, and their associated Piwi proteins, guard germ cell genomes against mobile genetic elements via an RNAi-like mechanism. In C. elegans, 21U-RNAs comprise the piRNA class and these collaborate with 22G RNAs, via unclear mechanisms, to discriminate self from non-self and selectively and heritably silence the latter. Recent work indicates that 21U-RNAs are post-transcriptional processing products of individual transcription units that produce ~26 nucleotide capped precursors. Yet, nothing is known of how the expression of precursors is controlled or of how primary transcripts give rise to mature small RNAs. We conducted a genome-wide RNAi screen to identify components of the 21U biogenesis machinery. Screening by direct, qPCR-based measurements of mature 21U-RNA levels, we identified 22 genes important for 21U-RNA production, termed TOFUs (Twenty-One-u Fouled Up). We also identified 7 genes that normally repress 21U production. By measuring mature 21U-RNA and precursor levels for the 7 strongest hits from the screen, we have assigned factors to discrete stages of 21U-RNA production. Our work has identified factors separately required for the transcription of 21U precursors, and the processing of these precursors into mature 21U-RNAs, thereby providing an essential resource for studying the biogenesis of this important small RNA class. Overall design: Small RNA and capped small RNA sequencing from total RNA of C. elegans subjected to different RNAi and different C. elegans mutants
Publication Title
A genome-wide RNAi screen identifies factors required for distinct stages of C. elegans piRNA biogenesis.
Sample Metadata Fields
Age, Subject
View Samples- Zea mays
- 10 Downloadable Samples
- Illumina HiSeq 2000, Illumina Genome Analyzer IIx
Description
Maize LEAFBLADELESS1 (LBL1) and Arabidopsis SUPPRESSOR OF GENE SILENCING3 (SGS3) play orthologous roles in the biogenesis of 21 nucleotide trans-acting short-interfering RNAs (tasiRNAs). The phenotypes conditioned by mutation of lbl1 and SGS3 are, however, strikingly different, suggesting that the activities of these small RNA biogenesis components, or the tasiRNAs and their targets might not be entirely conserved. To investigate the basis for this phenotypic variation, we compared the small RNA content between wild-type and lbl1 seedling apices. We show that LBL1 affects all major classes of small RNAs, and reveal unexpected crosstalk between tasiRNA biogenesis and other small RNA pathways regulating miRNAs, retrotransposons, and DNA transposons. We further identified genomic regions generating phased siRNAs, including numerous loci generating 22-nt phased small RNAs from long hairpin RNAs or overlapping antisense transcripts not previously described in other plant species. By combining both analyses, we identified nine TAS loci, all belonging to the conserved TAS3 family. Contrary to other plant species, no TAS loci targeted by a single miRNA were identified. Information from target prediction, RNAseq, and PARE analyses identified the tasiARFs as the major functional tasiRNAs in the maize vegetative apex where they regulate expression of ARF3 homologs. As such, divergence in TAS pathways is unlikely to account for the distinct phenotypes of tasiRNA biogenesis mutants in Arabidopsis and maize. Instead, the data suggests variation in the spatiotemporal regulation of ARF3, or divergence in its function, as a plausible basis for the dramatic phenotypic differences observed upon mutation of SGS3/lbl1 in Arabidopsis and maize. Overall design: An analysis of tasiRNA biogenesis, activity, and contribution to developmental phenotypes in the maize leaf. Data generated includes small RNA sequencing data and mRNA sequencing data. All data was generated in both wild type and lbl1 mutant maize leaf apices. Three replicates were generated for each genotype for the small RNA data. Two of these replicates were also used for the RNA-seq data.
Publication Title
Genome-wide analysis of leafbladeless1-regulated and phased small RNAs underscores the importance of the TAS3 ta-siRNA pathway to maize development.
Sample Metadata Fields
Age, Specimen part, Subject
View Samples- Mus musculus
- 8 Downloadable Samples
- Illumina Genome Analyzer
Description
In germ cells, Piwi proteins interact with a specific class of small non-coding RNAs, piwi-interacting RNAs (piRNAs). Together, these form a pathway that represses transposable elements, thus safeguarding germ cell genomes. While basic models describe the operation of piRNA pathways, neither the protein compositions of Piwi complexes, the critical protein-protein interactions that drive small RNA production and target recognition, or the precise molecular consequences of conserved localization to germline structures, call nuage, is well understood. We purified the three murine Piwi family proteins, Mili, Miwi, and Miwi2, from mouse germ cells and characterized their interacting protein partners. Piwi proteins were found in complex with Prmt5/Wdr77, an enzyme that di-methylates arginine residues. By immunoprecipitation with specific antibodies and by mass spectrometry, we found that Piwi proteins are arginine methylated at conserved positions in their amino termini. These modifications are essential to direct complex formation with specific Tudor-domain proteins, whose interactions with Piwis can be required for localization of RNP complexes in cytoplasmic nuage, proper piRNA expression, and transposon silencing. Considered together, our findings indicate that arginine methylation drives the assembly of multi-protein machines whose integrity and specific sub-cellular localization is necessary for efficient function of the piRNA pathway. Keywords: gene regulation study Overall design: Total small RNA in embryonic and post-birth mouse testes of tdrd1 and tdrd6 mutants
Publication Title
RNF17 blocks promiscuous activity of PIWI proteins in mouse testes.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 4 Downloadable Samples
- NextSeq 500
Description
Cell fate specification of neural stem/progenitor cells (NSCs) is an intricate developmental process that determines neural cell identity. While transcriptional mechanisms undoubtedly affect this process, translational mechanisms are much less understood. Here we show that deficiency of the chromatin remodeler Chromodomain Helicase DNA binding protein 5 (Chd5) causes transcriptional de-repression of multiple ribosomal subunit genes, increases protein synthesis, and expands the activated stem cell pool leading to perturbation of NSC fate. Compromised H3K27me3 in Chd5 deficient NSCs during early cell fate specification underlies the generation of excessive astrocytes at the expense of neurons at later stages of differentiation. Chd5 expression rescues these cell fate defects while simultaneously reestablishing H3K27me3, and inhibition of the H3K27me3-specific demethylase Utx restores appropriate cell fate specification in NSCs lacking Chd5. These findings define a Chd5-Utx-H3K27me3 axis pivotal in ribosome biogenesis and translation during neurogenesis, consistent with compromised CHD5 being implicated in glioma. Overall design: mRNA profiles of primary neural/stem progenitor cells (NSCs) of wild type (+/+) and Chd5-/- mice were generated, in duplicate, using Illumina NextSeq 500.
Publication Title
Chromatin-mediated translational control is essential for neural cell fate specification.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Rattus norvegicus
- 12 Downloadable Samples
Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Vasoregression is a hallmark of vascular eye diseases but the mechanisms involved are still largely unknown. We have recently characterized a rat ciliopathy model which develops primary photoreceptor degeneration and secondary vasoregression. To improve the understanding of secondary vasoregression in retinal neurodegeneration, we used microarray techniques to compare gene expression profiles in this new model before and after retinal vasoregression. Differential gene expression was validated by quantitative RT-PCR, Western blot and immunofluorescence. Of the 374 genes regulated more than twofold, the MHC class II invariant chain CD74 yielded the strongest upregulation, and was allocated to activated microglial cells close to the vessels undergoing vasoregression. Pathway clustering identified genes of the immune system, inflammatory signaling, and components of the complement cascade upregulated during vasoregression. Furthermore, macroglial cells were markedly activated. Together, our data suggest that glial cells involved in retinal immune response participate in the initiation of vasoregression in the retina.
Publication Title
Gene expression profiling of vasoregression in the retina--involvement of microglial cells.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 18 Downloadable Samples
- Illumina HiSeq 2500
Description
To uncover genes regulated by mTORC1 and estradiol in uterine Tsc2-null LAM like cells, we performed RNAseq on uteri from 12-week old wild-type (WT) and uterine-specific Tsc2-null (KO) mice that were either untreated (intact), oopherectomized (ovx) or oopherectomized + treated with 17ß-estradiol pellets (E2) for 8 weeks. We identified genes that were both estradiol- and TSC2-mediated. Overall design: Uterine mRNA profiles of 12 week old wild type (WT) and uterine-specific Tsc2-null (KO) mice in the presence or absence of estradiol were generated using Illumina HiSeq2500
Publication Title
Estrogen maintains myometrial tumors in a lymphangioleiomyomatosis model.
Sample Metadata Fields
Age, Specimen part, Cell line, Treatment, Subject
View Samples- Mus musculus
- 17 Downloadable Samples
- Affymetrix Mouse Gene 2.0 ST Array (mogene20st)
Description
Hyperglycemic memory is part of the pathogenesis of diabetic retinopathy. We established a novel mouse model of intermediate-term hyperglycemic memory and demonstrated that changes in gene expression and microvascular damage in the neurovascular unit of the diabetic retina persist after euglycemic reentry, indicating memory.
Publication Title
Hyperglycaemic memory affects the neurovascular unit of the retina in a diabetic mouse model.
Sample Metadata Fields
Specimen part, Disease
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The endocytic receptor megalin constitutes the main pathway for clearance of plasma proteins from the glomerular filtrate in the proximal tubules. However, little is know about the mechanisms that control receptor activity. A widely discussed hypothesis states that the intracellular domain (ICD) of megalin, released upon ligand binding, acts as a transcription regulator to suppress receptor expression - a mechanism proposed to safeguard the proximal tubules from protein overload. Here, we have put this hypothesis to the test by generating a mouse model co-expressing the soluble ICD and the full-length receptor. Despite pronounced expression in the proximal tubules, the ICD failed to exert any effects on renal proximal tubular function such as megalin expression, protein retrieval, or renal gene transcription. Thus, our data argue that the ICD does not play a role in regulation of megalin activity in vivo in the proximal tubules.
Publication Title
The soluble intracellular domain of megalin does not affect renal proximal tubular function in vivo.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Gene 2.1 ST Array (mogene21st)
Description
Long-term pharmacological glucocorticoid therapy causes atrophy and hypofunction of the adrenal cortex. Following glucocorticoids withdrawal, a functional and anatomic regeneration take place, whose cellular and molecular mechanisms are poorly understood
Publication Title
Sonic Hedgehog and WNT Signaling Promote Adrenal Gland Regeneration in Male Mice.
Sample Metadata Fields
Age, Specimen part
View Samples- Homo sapiens
- 52 Downloadable Samples
- Illumina HumanRef-8 v3.0 expression beadchip, Illumina HumanHT-12 V4.0 expression beadchip
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Immunopathology of childhood celiac disease-Key role of intestinal epithelial cells.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples