A Pandas complex adapted for piRNA-guided transposon silencing (CLIP-seq)
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA533630 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR8929000.fastq.gz | Fastqsanger.gz | |||
| SRR8929001.fastq.gz | Fastqsanger.gz | |||
| SRR8929002.fastq.gz | Fastqsanger.gz | |||
| SRR8929003.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 4 of 4 |
Similar Datasets
Project description:The repression of transposons by the Piwi-interacting RNA (piRNA) pathway is essential to protect animal germ cells. In Drosophila ovaries, Panoramix (Panx) enforces transcriptional silencing by binding to the target-engaged Piwi-piRNA complex, although the precise mechanisms by which this occur remain elusive. Here, we show that Panx functions together with a germline specific paralogue of a nuclear export factor, dNxf2, and its cofactor dNxt1 (p15) as a ternary complex to suppress transposon expression. Structural and functional analysis demonstrate that dNxf2 binds Panx via its UBA domain and play an important role in transposon silencing through binding to transposon transcripts directly. Unexpectedly, dNxf2 interacts directly with dNxf1 (TAP), which is also essential for transposon silencing. Transient tethering of dNxf2 to nascent transcripts leads to their nuclear retention. Therefore, we propose that dNxf2 may function as a Pandas (Panoramix dNxf2 dependent TAP/p15 silencing) complex, which counteracts the canonical RNA exporting machinery (TAP/p15) and restricts transposons to nuclear peripheries. Our finding may have broader implications for understanding how RNA metabolism modulates epigenetic gene silencing and heterochromatin formation.
2019-08-09 | GSE130041 | GEO
Project description:The repression of transposons by the Piwi-interacting RNA (piRNA) pathway is essential to protect animal germ cells. In Drosophila ovaries, Panoramix (Panx) enforces transcriptional silencing by binding to the target-engaged Piwi-piRNA complex, although the precise mechanisms by which this occur remain elusive. Here, we show that Panx functions together with a germline specific paralogue of a nuclear export factor, dNxf2, and its cofactor dNxt1 (p15) as a ternary complex to suppress transposon expression. Structural and functional analysis demonstrate that dNxf2 binds Panx via its UBA domain and play an important role in transposon silencing through binding to transposon transcripts directly. Unexpectedly, dNxf2 interacts directly with dNxf1 (TAP), which is also essential for transposon silencing. Transient tethering of dNxf2 to nascent transcripts leads to their nuclear retention. Therefore, we propose that dNxf2 may function as a Pandas (Panoramix dNxf2 dependent TAP/p15 silencing) complex, which counteracts the canonical RNA exporting machinery (TAP/p15) and restricts transposons to nuclear peripheries. Our finding may have broader implications for understanding how RNA metabolism modulates epigenetic gene silencing and heterochromatin formation.
2019-08-09 | GSE121158 | GEO
Project description:A Pandas complex adapted for piRNA-guided transposon silencing (RNA-seq)
| PRJNA495904 | ENA
Project description:The repression of transposons by the Piwi-interacting RNA (piRNA) pathway is essential to protect animal germ cells. In Drosophila ovaries, Panoramix (Panx) enforces transcriptional silencing by binding to the target-engaged Piwi-piRNA complex, although the precise mechanisms by which this occur remain elusive. Here, we show that Panx functions together with a germline specific paralogue of a nuclear export factor, dNxf2, and its cofactor dNxt1 (p15) as a ternary complex to suppress transposon expression. Structural and functional analysis demonstrate that dNxf2 binds Panx via its UBA domain and play an important role in transposon silencing through binding to transposon transcripts directly. Unexpectedly, dNxf2 interacts directly with dNxf1 (TAP), which is also essential for transposon silencing. Transient tethering of dNxf2 to nascent transcripts leads to their nuclear retention. Therefore, we propose that dNxf2 may function as a Pandas (Panoramix dNxf2 dependent TAP/p15 silencing) complex, which counteracts the canonical RNA exporting machinery (TAP/p15) and restricts transposons to nuclear peripheries. Our finding may have broader implications for understanding how RNA metabolism modulates epigenetic gene silencing and heterochromatin formation.
2019-08-09 | GSE130042 | GEO
Project description:A Pandas complex adapted for piRNA-guided transposon silencing and heterochromatin formation
| PRJNA533628 | ENA
Project description:The repression of transposons by the Piwi-interacting RNA (piRNA) pathway is essential to protect animal germ cells. In Drosophila ovaries, Panoramix (Panx) enforces transcriptional silencing by binding to the target-engaged Piwi-piRNA complex, although the precise mechanisms by which this occurs remain elusive. Here, we show that Panx functions together with a germline specific paralogue of a nuclear export factor, dNxf2, and its cofactor dNxt1 (p15), as a ternary complex to suppress transposon expression. Similar to Panx, dNxf2 is essential for animal fertility. Structural and functional analyses demonstrate that dNxf2 binds Panx via its UBA domain, which plays an important role in transposon silencing. Unexpectedly, dNxf2 interacts directly with dNxf1 (TAP), a general nuclear export factor. As a result, dNxf2 prevents dNxf1 from binding to the FG repeats of the nuclear pore complex, a process required for proper RNA export. Transient tethering of dNxf2 to nascent transcripts leads to their nuclear retention. Thus, dNxf2 functions in a Pandas (Panoramix dNxf2 dependent TAP/p15 silencing) complex, which counteracts the canonical RNA exporting machinery and restricts transposons to the nuclear peripheries. Our findings may have broader implications for understanding how RNA metabolism regulates epigenetic gene silencing and heterochromatin formation.
2019-08-06 | PXD014926 |
Project description:PIWI-clade Argonaute proteins silence transposon expression in animal gonads. Their target specificity is defined by bound ~23-30nt piRNAs that are processed from single-stranded precursor transcripts via two distinct pathways. Primary piRNAs are defined by the endo-nuclease Zucchini, while biogenesis of secondary piRNAs depends on piRNA-guided transcript cleavage and results in piRNA amplification. Here, we analyze the inter-dependencies between these piRNA biogenesis pathways in the developing Drosophila ovary. We show that secondary piRNA-guided target slicing is the predominant mechanism that specifies transcripts—including those from piRNA clusters—as primary piRNA precursors and that defines the spectrum of Piwi-bound piRNAs in germline cells. Post-transcriptional silencing in the cytoplasm therefore enforces nuclear, transcriptional target silencing, which ensures the tight suppression of transposons during oogenesis. As target slicing also defines the nuclear piRNA pool during mouse spermatogenesis, our findings uncover an unexpected conceptual similarity between the mouse and fly piRNA pathways.
2015-08-31 | GSE71775 | GEO
Project description:PIWI-clade Argonaute proteins silence transposon expression in animal gonads. Their target specificity is defined by bound ~23-30nt piRNAs that are processed from single-stranded precursor transcripts via two distinct pathways. Primary piRNAs are defined by the endo-nuclease Zucchini, while biogenesis of secondary piRNAs depends on piRNA-guided transcript cleavage and results in piRNA amplification. Here, we analyze the inter-dependencies between these piRNA biogenesis pathways in the developing Drosophila ovary. We show that secondary piRNA-guided target slicing is the predominant mechanism that specifies transcripts—including those from piRNA clusters—as primary piRNA precursors and that defines the spectrum of Piwi-bound piRNAs in germline cells. Post-transcriptional silencing in the cytoplasm therefore enforces nuclear, transcriptional target silencing, which ensures the tight suppression of transposons during oogenesis. As target slicing also defines the nuclear piRNA pool during mouse spermatogenesis, our findings uncover an unexpected conceptual similarity between the mouse and fly piRNA pathways. To understand the hierarchical order of primary versus secondary piRNA biogenesis in Drosophila ovaries, we sequenced piRNAs bound to total-Piwi, germline-Piwi, Aubergine and Argonaute3 from ovaries of germline specific knockdowns of control, piwi, aub, ago3 single knockdowns and aub/ago3 double knockdowns. To determine changes in Transposable Element (TE) transcription or TE RNA steady state in perturbed piRNA pathway conditions, we performed Pol2-ChIP-sequencing and polyA bound RNA-sequencing from ovaries of multiple germline knockdown genotypes. We also sequenced genomic DNA from ovaries of control knockdowns to experimentally estimate the TE copy number in our genetic background. Finally, we used CAP-seq from germline specific Piwi depletions to identify the Transcriptional Start Sites (TSS) in TEs in a deregulated background. Replicates are labeled with R1, R2, R3, R4 where indicated.
2015-08-31 | E-GEOD-71775 | biostudies-arrayexpress
Project description:PIWI-clade Argonaute proteins repress transposable elements in animal gonads. Their sequence specificity is conferred via bound ~23-30nt long piRNAs, which are processed from single stranded precursor RNAs. How transcripts are specified as precursors and processed into stereotypical piRNA populations are central unresolved questions. Here we show that piRNA-guided RNA cleavage in Drosophila results not only in generation of a ping-pong partner piRNA but further triggers efficient 3′ directed and phased primary piRNA biogenesis. Phasing is a feature of primary piRNAs in somatic and germline cells and a consequence of consecutive endo-nucleolytic cleavage events catalyzed by Zucchini. Formation of 3′ and 5′ ends of flanking piRNAs is therefore tightly coupled. Zucchini also participates in 3′ end formation of secondary piRNAs but its function can be bypassed by additional downstream piRNA-guided cleavages and subsequent precursor trimming. Hallmarks of Zucchini-dependent phased piRNA biogenesis are also evident in mouse testes, pointing to an evolutionarily conserved mechanism of piRNA biogenesis. This study aims at understanding how piRNA biogenesis is intiated in the Drosophila germline and understanding the role of the nuclease Zucchini/MitoPLD in piRNA biogenesis in Drosophila/Mouse by analysing small RNA sequencing data of various genotypes and sensor constructs.
2015-06-07 | E-GEOD-64802 | biostudies-arrayexpress
Project description:PIWI-clade Argonaute proteins repress transposable elements in animal gonads. Their sequence specificity is conferred via bound ~23-30nt long piRNAs, which are processed from single stranded precursor RNAs. How transcripts are specified as precursors and processed into stereotypical piRNA populations are central unresolved questions. Here we show that piRNA-guided RNA cleavage in Drosophila results not only in generation of a ping-pong partner piRNA but further triggers efficient 3′ directed and phased primary piRNA biogenesis. Phasing is a feature of primary piRNAs in somatic and germline cells and a consequence of consecutive endo-nucleolytic cleavage events catalyzed by Zucchini. Formation of 3′ and 5′ ends of flanking piRNAs is therefore tightly coupled. Zucchini also participates in 3′ end formation of secondary piRNAs but its function can be bypassed by additional downstream piRNA-guided cleavages and subsequent precursor trimming. Hallmarks of Zucchini-dependent phased piRNA biogenesis are also evident in mouse testes, pointing to an evolutionarily conserved mechanism of piRNA biogenesis.
2015-06-07 | GSE64802 | GEO