GEO DataSets

(Submitter supplied) Transgenes containing a fragment of I transposon represent a powerful model of piRNA cluster de novo formation in the Drosophila germline. We revealed that the same transgenes located at different genomic loci form piRNA clusters with various capacity of small RNA production. Transgenic piRNA clusters are not established in piRNA pathway mutants. However, in wild-type context, the endogenous ancestral I-related piRNAs are sufficient to heterochromatinize and convert the I-containing transgenes into piRNA-producing loci. more...

Organism:

Drosophila melanogaster

Type:

Expression profiling by high throughput sequencing; Non-coding RNA profiling by high throughput sequencing; Other

Platforms:

GPL25244 GPL17275

20 Samples

Download data: BW, TXT

(Submitter supplied) Expression of transposable elements in the germline is controlled by Piwi-interacting (pi) RNAs produced by genomic loci termed piRNA clusters and associated with Rhino, a Heterochromatin Protein 1 (HP1) homolog. Previously, we have shown that transgenes containing a fragment of the I retrotransposon form de novo piRNA clusters in the Drosophila germline providing suppression of I-element activity. We noted that identical transgenes located in different genomic sites vary considerably in piRNA production and classified them as “strong” and “weak” piRNA clusters. Here, we investigated what chromatin and transcriptional changes occur at the transgene insertion sites after their conversion into piRNA clusters. We found that the formation of a transgenic piRNA cluster is accompanied by activation of transcription from both genomic strands that likely initiates at multiple random sites. The chromatin of all transgene-associated piRNA clusters contain high levels of trimethylated lysine 9 of histone H3 (H3K9me3) and HP1a, whereas Rhino binding is considerably higher at the strong clusters. None of these chromatin marks was revealed at the “empty” sites before transgene insertion. Finally, we have shown that in the nucleus of polyploid nurse cells, the formation of a piRNA cluster at a given transgenic genomic copy works according to an “all– or– nothing” model: either there is high Rhino enrichment or there is no association with Rhino at all. As a result, genomic copies of a weak piRNA transgenic cluster show a mosaic association with Rhino foci, while the majority of strong transgene copies associate with Rhino and are hence involved in piRNA production.

Organism:

Drosophila melanogaster

Type:

Other; Non-coding RNA profiling by high throughput sequencing

Platforms:

GPL13304 GPL17275

3 Samples

Download data: BW, TXT

(Submitter supplied) In the Drosophila germline, transposable elements (TEs) are silenced by PIWI-interacting RNA (piRNA) that originate from distinct genomic regions termed piRNA clusters and are processed by PIWI-subfamily Argonaute proteins. Here, we explore the variation in the ability to restrain an alien TE in different Drosophila strains. The I-element is a retrotransposon involved in the phenomenon of I-R hybrid dysgenesis in Drosophila melanogaster. more...

Organism:

Drosophila melanogaster

Type:

Non-coding RNA profiling by high throughput sequencing

Platform:

GPL13304

7 Samples

Download data: TXT

(Submitter supplied) Expression profiling of Drosophila neurons visualized with transgenic reporter genes, 7.4 kb Cha-Gal:UAS-GFP or 2.1 kb Gad1(s)-RFP. Keywords: neuronal cell type comparison

Organism:

Drosophila melanogaster

Type:

Expression profiling by array

Platform:

GPL1322

10 Samples

Download data: CEL

(Submitter supplied) We analysed the effect of the deficiency Df(2R)ED3921 and Df(2R)ED50000 on gene expression in embryos (stage 0-11), and wing imaginal discs and brains from 3rd instar larvae. Df(2R)ED3921 and Df(2R)ED50000 were described in Ragab et al. (2005) Genetics 172:1069-1078 2005.

Organism:

Drosophila melanogaster

Type:

Expression profiling by array

Platform:

GPL5016

21 Samples

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