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SRP013751
Drosophila melanogaster
13 Downloadable Samples
Illumina HiSeq 2000
Description
In animal gonads, 23-30nt long PIWI interacting RNAs (piRNAs) guarantee genome integrity by guiding the sequence specific silencing of selfish genetic elements such as transposons. Two major branches of piRNA biogenesis, namely primary processing and ping-pong amplification, feed into the PIWI clade of Argonaute proteins. Despite our conceptual understanding of piRNA biogenesis, major gaps exist in the mechanistic understanding of the underlying molecular processes as well as in the knowledge of the involved players. Here, we demonstrate an essential role for the female sterility gene shutdown in the piRNA pathway. Shutdown, an evolutionarily conserved co-chaperone of the immunophilin class is the first piRNA biogenesis factor that is essential for all primary and secondary piRNA populations in Drosophila. Based on these findings, we define distinct groups of piRNA biogenesis factors and reveal the core concept of how PIWI family proteins are hard-wired into piRNA biogenesis processes. Overall design: small-RNA libraries from 2 control samples and 7 knock-down samples of D. mel. ovaries and 2 small-RNA profiles from Piwi IP and Aub IP from OSCs.
Publication Title
The cochaperone shutdown defines a group of biogenesis factors essential for all piRNA populations in Drosophila.
Sample Metadata Fields
Specimen part, Subject
View Samples- Drosophila melanogaster
- 5 Downloadable Samples
- Illumina Genome Analyzer II
Description
In Drosophila, PIWI proteins and bound PIWI interacting RNAs (piRNAs) form the core of a small RNA mediated defense system against selfish genetic elements. Within germline cells piRNAs are processed from piRNA clusters and transposons to be loaded into Piwi/Aubergine/AGO3 and a subset of piRNAs undergoes target dependent amplification. In contrast, gonadal somatic support cells express only Piwi, lack signs of piRNA amplification and exhibit primary piRNA biogenesis from piRNA clusters. Neither piRNA processing/loading nor Piwi mediated target silencing is understood at the genetic, cellular or molecular level. We developed an in vivo RNAi assay for the somatic piRNA pathway and identified the RNA helicase Armitage, the Tudor domain containing RNA helicase Yb and the putative nuclease Zucchini as essential factors for primary piRNA biogenesis. Lack of any of these proteins leads to transposon de-silencing, to a collapse in piRNA levels and to a failure in Piwi nuclear accumulation. We show that Armitage and Yb interact physically and co-localize in cytoplasmic Yb-bodies, which flank P-bodies. Loss of Zucchini leads to an accumulation of Piwi and Armitage in Yb-bodies indicating that Yb-bodies are sites of primary piRNA biogenesis. Overall design: small RNA libraries were prepared from Piwi immuno-precipitates of five different genotypes
Publication Title
An in vivo RNAi assay identifies major genetic and cellular requirements for primary piRNA biogenesis in Drosophila.
Sample Metadata Fields
Subject
View Samples- Zea mays
- 6 Downloadable Samples
- Illumina HiSeq 2000
Description
Gray leaf spot (GLS) disease of maize can be caused by either of two sibling fungal species Cercospora zeina or Cercospora zeae-maydis. These species differ in geographical distribution, for example to date only C. zeina is associated with GLS in African countries, such as South Africa. Maize inbred line B73, which is susceptible to GLS, was planted in the field, and subjected to natural infection with C. zeina. Samples were collected from lower leaves with substantial GLS lesions and younger upper leaves of the same plants with very few immature GLS lesions. The first aim of the experiment was to determine which maize genes are induced in response to C. zeina infection. The second aim was to identify C. zeina genes expressed in planta during a compatible interaction. The third aim was to determine whether the C. zeina cercosporin biosynthetic (CTB) genes are expressed in planta. C. zeina fails to produce cercosporin in vitro in contrast to C. zeae-maydis. Cercosporin is a phytotoxin that is thought to play a role in pathogenicity of several Cercospora spp., however its role in the pathogenicity strategy of C. zeina is currently under investigation. Overall design: To collect material that reflected a difference between C. zeina infected B73 leaves and control B73 leaf material, samples were collected from two lower GLS infected leaves (second and third leaf internode below ear), and two upper leaves with minimal GLS symptoms (second and third internode above ear), respectively. The two lower leaves from each plant were pooled prior to RNA extraction, and the two upper leaves from each plant were pooled prior to RNA extraction. Upper and lower leaf samples from three maize B73 plants were subjected to RNA sequencing individually. The three maize plants were selected randomly as one plant per row from three rows of ten B73 plants each.
Publication Title
Complementation of CTB7 in the Maize Pathogen Cercospora zeina Overcomes the Lack of In Vitro Cercosporin Production.
Sample Metadata Fields
Specimen part, Subject
View Samples- Mus musculus
- 3 Downloadable Samples
Illumina MouseWG-6 v2.0 expression beadchip
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Dnmt3L antagonizes DNA methylation at bivalent promoters and favors DNA methylation at gene bodies in ESCs.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 3 Downloadable Samples
- Illumina MouseWG-6 v2.0 expression beadchip
Description
The de novo DNA methyltransferase 3-like (Dnmt3L) is a catalytically inactive DNA methylase that has been previously shown to cooperate with Dnmt3a and Dnmt3b to methylate DNA. Dnmt3L is highly expressed in mouse embryonic stem cells (ESC) but its function in these cells is unknown. We here report that Dnmt3L is required for the differentiation of ESC into primordial germ cells (PGC) through activation of the homeotic gene Rhox5. By genome-wide analysis we found that Dnmt3L is a positive regulator of methylation at gene bodies of housekeeping genes and a negative regulator of methylation at promoters of bivalent genes. We demonstrate that Dnmt3L interacts with the Polycomb PRC2 complex in competition with the DNA methyl transferases Dnmt3a and Dnmt3b to maintain low the methylation level at H3H27me3 regions. Thus in ESC, Dnmt3L counteracts the activity of de novo DNA methylases to keep low the level of DNA methylation at developmental gene promoters.
Publication Title
Dnmt3L antagonizes DNA methylation at bivalent promoters and favors DNA methylation at gene bodies in ESCs.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 8 Downloadable Samples
- Illumina Genome Analyzer II
Description
PIWI proteins and their bound piRNAs form the core of a gonad specific small RNA silencing pathway in animals that protects the genome against the deleterious activity of transposable elements. Recent studies linked the piRNA pathway to TUDOR biology, where TUDOR domains of various proteins recognize and bind symmetrically methylated Arginine residues in PIWI proteins. We systematically analyzed the Drosophila TUDOR protein family and identified three previously not characterized TUDOR domain-containing genes (CG4771, CG14303 and CG11133) as essential piRNA pathway members. We characterized CG4771 (Avocado) in detail and demonstrate a critical role for this protein during primary piRNA biogenesis in somatic and germline cells of the ovary. Avocado physically and/or genetically interacts with the primary pathway components Piwi, Armitage, Yb and Zucchini. Avocado also interacts with the Tdrd12 orthologs CG11133 and CG31755, which are essential for primary piRNA biogenesis in the germline and probably functionally replace the related and soma specific factor Yb. Overall design: small RNA libraries were prepared from total RNA isolation of 8 different genotypes
Publication Title
A systematic analysis of Drosophila TUDOR domain-containing proteins identifies Vreteno and the Tdrd12 family as essential primary piRNA pathway factors.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 2 Downloadable Samples
- IlluminaHiScanSQ
Description
Ten eleven translocation (TET) enzymes catalyse the oxidative reactions of 5-methylcytosine (5mC) to promote the demethylation process. The reaction intermediate 5-hydroxymethylcytosine (5hmC) has been shown to be abundant in embryonic stem cells and tissues, but strongly depleted in human cancers. Genetic mutations of TET2 gene were associated with lleukemia, whereas TET1 downregulation has been shown to promote malignancy in breast cancer. Here, we report that TET1 is downregulated in colon tumours from the initial stage. TET1 silencing in primary epithelial colon cells increase their cellular proliferation while its re-expression in colon cancer cells inhibits their proliferation and the growth of tumour xenografts even at later stages. We found that TET1 binds and maintains hypomethylated the promoter of the DKK genes inhibitors of the WNT signalling to promote their expression. Downregulation of TET1 during colon cancer initiation leads to repression, by DNA methylation the promoters of the inhibitors of the WNT pathway resulting in a constitutive activation of the WNT pathway. Thus the DNA hydroxymethylation mediated by TET1 controlling the WNT signalling is a key player of tumour growth. These results provide new insights for understanding how tumours escape cellular controls Overall design: Transcriptome analysis of Caco-2 cell line expressing TET1 protein.
Publication Title
TET1 is a tumour suppressor that inhibits colon cancer growth by derepressing inhibitors of the WNT pathway.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 44 Downloadable Samples
Description
The incidence of pulmonary nontuberculous mycobacterial (PNTM) disease is increasing, but host susceptibility factors are not fully understood. We infected air-liquid interface (ALI) primary respiratory epithelial cell cultures with Mycobacterium avium complex (MAC) or Mycobacterium abscessus (MAB) and performed transcriptome sequencing (RNA-Seq) to identify relevant gene expression differences. We used cells from 4 different donors in order to try to obtain generalizable data. The differentiated respiratory epithelial cells in ALI were infected with MAC or MAB at MOI of 100:1 or 1000:1, and RNA-seq was performed at 1 and 3 days after infection. We found downregulation of ciliary genes, including several identified with polymorphisms in previous PNTM cohorts. The cytokine IL-32, the superpathway of cholesterol biosynthesis and downstream targets within the IL-17 signaling pathway were all elevated. The integrin signaling pathway was more upregulated by MAB than MAC infection. Working with primary respiratory epithelial cells infected with nontuberculous mycobacteria at ALI, we identified ciliary function, cholesterol biosynthesis, chemokine production and the IL-17 pathway as major targets of host responses to infection. Some of these pathways may be amenable to therapeutic manipulation. Overall design: 44 strand-specific RNA libraries for high-throughput sequencing were prepared (samples from 4 different donors, 57F, 75M, 69F, and 42F, for each condition) using the TruSeq Stranded mRNA Sample Preparation Kit with 750ng of total RNA according to manufacturer's instructions.
Publication Title
Transcriptional Response of Respiratory Epithelium to Nontuberculous Mycobacteria.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 11 Downloadable Samples
- Illumina HiScanSQ
Description
Phenotypic changes induced by extracellular vesicles (EVs) have been implicated in the recovery of acute kidney injury (AKI) induced by mesenchymal stromal cells (MSCs). miRNAs are potential candidates for cell reprogramming towards a pro-regenerative phenotype. The aim of the present study was to evaluate whether miRNA de-regulation inhibits the regenerative potential of MSCs and derived-EVs in a model of glycerol-induced AKI in SCID mice. For this purpose, we generated MSCs depleted of Drosha, a critical enzyme of miRNA maturation, to alter miRNA expression within MSCs and EVs. Drosha knock-down MSCs (MSC-Dsh) maintained the phenotype and differentiation capacity. They produced EVs that did not differ from those of wild type cells in quantity, surface molecule expression and internalization within renal tubular epithelial cells. However, EVs derived from MSC-Dsh (EV-Dsh) showed global down-regulation of miRNAs. Whereas, wild type MSCs and derived EVs were able to induce morphological and functional recovery in AKI, MSC-Dsh and EV-Dsh were ineffective. RNA sequencing analysis showed that genes deregulated in the kidney of AKI mice were restored by treatment with MSCs and EVs but not by MSC-Dsh and EV-Dsh. Gene Ontology analysis showed that down-regulated genes in AKI were associated with fatty acid metabolism. The up-regulated genes in AKI were involved in inflammation, ECM-receptor interaction and cell adhesion molecules. These alterations were reverted by treatment with wild type MSCs and EVs, but not by the Drosha counterparts. In conclusion, miRNA depletion in MSCs and EVs significantly reduced their intrinsic regenerative potential in AKI, suggesting a critical role of miRNAs. Overall design: RNA-seq
Publication Title
AKI Recovery Induced by Mesenchymal Stromal Cell-Derived Extracellular Vesicles Carrying MicroRNAs.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 298 Downloadable Samples
- Illumina HumanWG-6 v3.0 expression beadchip
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
A comprehensive analysis of adiponectin QTLs using SNP association, SNP cis-effects on peripheral blood gene expression and gene expression correlation identified novel metabolic syndrome (MetS) genes with potential role in carcinogenesis and systemic inflammation.
Sample Metadata Fields
Sex, Age, Race
View Samples