Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Specialization of the Drosophila nuclear export family protein, Nxf3, for piRNA precursor export

ABSTRACT: The piRNA pathway is a conserved small RNA-based immune system that protects animal germ cell genomes from the harmful effects of transposon mobilisation. In Drosophila ovaries, most piRNAs originate from dual-strand clusters, which generate piRNAs from both genomic strands. Dual-strand clusters use non-canonical transcription mechanisms. Although transcribed by RNA polymerase II, cluster transcripts lack splicing signatures and polyA tails. mRNA processing is important for general mRNA export mediated by Nuclear export factor 1. Although UAP56, a component of the transcription and export complex, has been implicated in piRNA precursor export, it remains unknown how dual-strand cluster transcripts are specifically targeted for piRNA biogenesis by export from the nucleus to cytoplasmic processing centers. Here we report that dual-strand cluster transcript export requires CG13741/Bootlegger and the Drosophila Nuclear export factor family protein, Nxf3. Bootlegger is specifically recruited to piRNA clusters and in turn brings Nxf3. We find that Nxf3 specifically binds to piRNA precursors and is essential for their export to piRNA biogenesis sites, a process that is critical for germline transposon silencing. Our data shed light on how dual-strand clusters bypass canonical mRNA features to be specifically exported via Nxf3, ensuring proper piRNA production.

ORGANISM(S): Drosophila melanogaster

PROVIDER: GSE133528 | GEO | 2019/07/27

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Specialization of the Drosophila nuclear export family protein, Nxf3, for piRNA precursor export

Project description:The piRNA pathway is a conserved small RNA-based immune system that protects animal germ cell genomes from the harmful effects of transposon mobilisation. In Drosophila ovaries, most piRNAs originate from dual-strand clusters, which generate piRNAs from both genomic strands. Dual-strand clusters use non-canonical transcription mechanisms. Although transcribed by RNA polymerase II, cluster transcripts lack splicing signatures and polyA tails. mRNA processing is important for general mRNA export mediated by Nuclear export factor 1. Although UAP56, a component of the transcription and export complex, has been implicated in piRNA precursor export, it remains unknown how dual-strand cluster transcripts are specifically targeted for piRNA biogenesis by export from the nucleus to cytoplasmic processing centers. Here we report that dual-strand cluster transcript export requires CG13741/Bootlegger and the Drosophila Nuclear export factor family protein, Nxf3. Bootlegger is specifically recruited to piRNA clusters and in turn brings Nxf3. We find that Nxf3 specifically binds to piRNA precursors and is essential for their export to piRNA biogenesis sites, a process that is critical for germline transposon silencing. Our data shed light on how dual-strand clusters bypass canonical mRNA features to be specifically exported via Nxf3, ensuring proper piRNA production

2019-07-29 | PXD014472 | Pride

Requirement of Nuclear Pore Complex subunits for transposon silencing in Drosophila

Project description:The piRNA pathway is a small RNA-based immune system that silences mobile genetic elements in animal germlines. In Drosophila ovaries, piRNAs are produced from discrete genomic loci, called piRNA clusters, which are composed of inactive transposon copies and fragments and thus constitute a genetically encoded memory of past transposon challenges. Two types of piRNA clusters exist in flies: dual-strand clusters, expressed only in the germline via a highly specialised machinery, and uni-strand cluster, which are predominantly expressed in the somatic follicle cells. Flamenco (flam) is the major uni-strand piRNA cluster in Drosophila, giving rise to the majority of somatic piRNAs. Flam resembles a canonical RNA polymerase II transcriptional unit, nonetheless it can be specifically recognised by the piRNA pathway and directed to the biogenesis machinery. Recent work has implicated the RNA helicase Yb in the licensing of somatic piRNA production, however a detailed understanding of the molecular mechanisms underlying flam export and specification is still lacking. Here, we show that flam export triggers the assembly of peri-nuclear condensates of Yb and provide evidence that piRNA production from flam specifically requires subunits of the Nuclear Pore Complex (NPC). In the absence of some NPC subunits, transposons become de-silenced and piRNA biogenesis is compromised exclusively from flam. We also show that Yb transiently associates with the NPC to promote flam export. Taken together, our data shed light on how the export of uni-strand cluster transcripts is achieved and suggest the evolution of a specialised machinery that couples transcription, nuclear export and piRNA production.

2021-04-16 | PXD019671 | Pride

Requirement of Nuclear Pore Complex subunits for transposon silencing in Drosophila

2021-07-02 | PXD019674 | Pride

Requirement of Nuclear Pore Complex Subunits for transposon silencing in Drosophila

2021-04-15 | PXD019670 | Pride

A heterochromatin-specific RNA export pathway facilitates piRNA production

Project description:PIWI-interacting RNAs (piRNAs) guide transposon silencing in animals. The 22-30nt piRNAs are processed in the cytoplasm from long non-coding RNAs. How piRNA precursors, which often lack RNA processing hallmarks of export-competent transcripts, achieve nuclear export is unknown. Here, we uncover the RNA export pathway specific for piRNA precursors in the Drosophila germline. This pathway requires Nxf3-Nxt1, a variant of the hetero-dimeric mRNA export receptor Nxf1-Nxt1. Nxf3 interacts with UAP56, a nuclear RNA helicase essential for mRNA export, and CG13741/Bootlegger, which recruits Nxf3-Nxt1 and UAP56 to heterochromatic piRNA source loci. Upon RNA cargo binding, Nxf3 achieves nuclear export via the exportin Crm1, and accumulates together with Bootlegger in peri-nuclear nuage, suggesting that after export, Nxf3-Bootlegger delivers precursor transcripts to the piRNA processing sites. Our findings indicate that the piRNA pathway bypasses nuclear RNA surveillance systems to achieve export of heterochromatic, unprocessed transcripts to the cytoplasm, a strategy also exploited by retroviruses.

2019-03-28 | GSE126578 | GEO

A heterochromatin specific RNA export pathway facilitates piRNA production

Project description:PIWI-interacting RNAs (piRNAs), a class of small RNAs that guide transposon silencing in animals, are processed in the cytoplasm from RNA Polymerase II transcripts. How piRNA precursors, which often lack RNA maturation signatures and thereby violate quality control checkpoints, achieve nuclear export is unknown. Here, we uncover a germline-specific RNA export pathway in Drosophila, that escorts piRNA precursors from their heterochromatic origins to nuage, the cytoplasmic piRNA processing centres. This pathway connects canonical nuclear export factors—the RNA helicase UAP56, the NXF cofactor Nxt1/p15, and the exportin Crm1/Xpo1—with Nxf3, a variant of the mRNA exporter Nxf1/Tap. Nxf3 recruitment to nascent piRNA precursors occurs via the heterochromatin protein 1-variant Rhino and CG13741/Bootlegger, a new piRNA pathway factor, thereby making piRNA precursor export independent of RNA processing events. Thus, similar to retroviral hijacking of cellular export factors, piRNA precursor export evolved to bend canonical gene expression rules through bypassing nuclear RNA surveillance mechanisms.

2019-03-29 | PXD012717 | Pride

UAP56 couples piRNA clusters to the perinuclear transposon silencing machinery [tiling array]

Project description:The transposon silencing piRNAs are produced from precursors that are encoded by heterochromatic clusters and processed in the perinuclear nuage. We show that the Drosophila nuclear DEAD box protein UAP56, previously implicated in mRNA splicing and nuclear export, co-localizes with the cluster-associated HP1 homologue Rhino. Prominent nuclear foci containing Rhi and UAP56 localize directly across the nuclear envelope from Vasa, a conserved DEAD box protein and core nuage component that is required for piRNA production, and piRNA precursors immunoprecipitate with both UAP56 and Vasa. A uap56 point mutation that prevents UAP56 protein co-localization with Rhino also disrupts nuage organization, transposon silencing, and expression of dual strand piRNA clusters. By contrast, this allele significantly increases ectopic piRNAs from protein coding genes. We therefore propose that UAP56 and Vasa organize a piRNA-processing compartment that spans the nuclear envelope, increasing the efficiency and specificity of piRNA biogenesis. 3 replicates of each sample (uap56, vasa), total RNA samples hybridized to tiling array.

2012-11-28 | E-GEOD-35636 | biostudies-arrayexpress

UAP56 couples piRNA clusters to the perinuclear transposon silencing machinery [RNA-Seq and RIP-Seq]

Project description:The transposon silencing piRNAs are produced from precursors that are encoded by heterochromatic clusters and processed in the perinuclear nuage. We show that the Drosophila nuclear DEAD box protein UAP56, previously implicated in mRNA splicing and nuclear export, co-localizes with the cluster-associated HP1 homologue Rhino. Prominent nuclear foci containing Rhi and UAP56 localize directly across the nuclear envelope from Vasa, a conserved DEAD box protein and core nuage component that is required for piRNA production, and piRNA precursors immunoprecipitate with both UAP56 and Vasa. A uap56 point mutation that prevents UAP56 protein co-localization with Rhino also disrupts nuage organization, transposon silencing, and expression of dual strand piRNA clusters. By contrast, this allele significantly increases ectopic piRNAs from protein coding genes. We therefore propose that UAP56 and Vasa organize a piRNA-processing compartment that spans the nuclear envelope, increasing the efficiency and specificity of piRNA biogenesis. RNA-Seq: 3 samples examined: w1118, uap56 mutant un-oxidized, uap56 mutant oxidized RIP-Seq: 6 samples: UAP56-Venus, sz-Venus, and wild type w1 with anti-flag and input control each.

2012-11-28 | E-GEOD-35637 | biostudies-arrayexpress

UAP56 couples piRNA clusters to the perinuclear transposon silencing machinery [RNA-Seq and RIP-Seq]

2012-11-28 | GSE35637 | GEO