Abstract

The PIWI-interacting RNA (piRNA) pathway is a small RNA-based immune system that controls the expression of transposons and maintains genome integrity in animal gonads. In Drosophila, piRNA-guided silencing is achieved, in part, via co-transcriptional repression of transposons by Piwi. This depends on Panoramix (Panx); however, precisely how an RNA binding event silences transcription remains to be determined. Here we show that Nuclear Export Factor 2 (Nxf2) and its co-factor, Nxt1, form a complex with Panx and are required for co-transcriptional silencing of transposons in somatic and germline cells of the ovary. Tethering of Nxf2 or Nxt1 to RNA results in silencing of target loci and the concomitant accumulation of repressive chromatin marks. Nxf2 and Panx proteins are mutually required for proper localization and stability. We mapped the protein domains crucial for the Nxf2/Panx complex formation and show that the amino-terminal portion of Panx is sufficient to induce transcriptional silencing.

Data availability

Sequencing data reported in this paper has been deposited in GEO under accession number GSE121661. Mass Spectrometry data has been deposited to the PRIDE Archive (accession number PXD011415)

The following data sets were generated

Article and author information

Author details

  1. Martin H Fabry

    Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Filippo Ciabrelli

    Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Marzia Munafò

    Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2689-8432
  4. Evelyn L Eastwood

    Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Emma Kneuss

    Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0662-8539
  6. Ilaria Falciatori

    Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Federica A Falconio

    Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Gregory J Hannon

    Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
    For correspondence
    greg.hannon@cruk.cam.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4021-3898
  9. Benjamin Czech

    Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
    For correspondence
    benjamin.czech@cruk.cam.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8471-0007

Funding

Wellcome (Investigator award 110161/Z/15/Z)

  • Gregory J Hannon

Cancer Research UK

  • Gregory J Hannon

European Molecular Biology Organization (Long-Term Fellowship ALTF 1015-2017)

  • Filippo Ciabrelli

Boehringer Ingelheim Fonds (PhD fellowship)

  • Marzia Munafò

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Torben Heick Jensen, Aarhus University, Denmark

Publication history

  1. Received: April 26, 2019
  2. Accepted: June 19, 2019
  3. Accepted Manuscript published: June 20, 2019 (version 1)
  4. Version of Record published: August 2, 2019 (version 2)

Copyright

© 2019, Fabry et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

Metrics

  • 3,125
    Page views
  • 464
    Downloads
  • 43
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Martin H Fabry
  2. Filippo Ciabrelli
  3. Marzia Munafò
  4. Evelyn L Eastwood
  5. Emma Kneuss
  6. Ilaria Falciatori
  7. Federica A Falconio
  8. Gregory J Hannon
  9. Benjamin Czech
(2019)
piRNA-guided co-transcriptional silencing coopts nuclear export factors
eLife 8:e47999.
https://doi.org/10.7554/eLife.47999

Further reading

    1. Chromosomes and Gene Expression
    2. Neuroscience
    Bradley M Colquitt, Kelly Li ... Michael S Brainard
    Research Article

    Sensory feedback is required for the stable execution of learned motor skills, and its loss can severely disrupt motor performance. The neural mechanisms that mediate sensorimotor stability have been extensively studied at systems and physiological levels, yet relatively little is known about how disruptions to sensory input alter the molecular properties of associated motor systems. Songbird courtship song, a model for skilled behavior, is a learned and highly structured vocalization that is destabilized following deafening. Here, we sought to determine how the loss of auditory feedback modifies gene expression and its coordination across the birdsong sensorimotor circuit. To facilitate this system-wide analysis of transcriptional responses, we developed a gene expression profiling approach that enables the construction of hundreds of spatially-defined RNA-sequencing libraries. Using this method, we found that deafening preferentially alters gene expression across birdsong neural circuitry relative to surrounding areas, particularly in premotor and striatal regions. Genes with altered expression are associated with synaptic transmission, neuronal spines, and neuromodulation and show a bias toward expression in glutamatergic neurons and Pvalb/Sst-class GABAergic interneurons. We also found that connected song regions exhibit correlations in gene expression that were reduced in deafened birds relative to hearing birds, suggesting that song destabilization alters the inter-region coordination of transcriptional states. Finally, lesioning LMAN, a forebrain afferent of RA required for deafening-induced song plasticity, had the largest effect on groups of genes that were also most affected by deafening. Combined, this integrated transcriptomics analysis demonstrates that the loss of peripheral sensory input drives a distributed gene expression response throughout associated sensorimotor neural circuitry and identifies specific candidate molecular and cellular mechanisms that support the stability and plasticity of learned motor skills.

    1. Chromosomes and Gene Expression
    Sarah E London
    Insight

    In songbirds, deafening leads to changes in gene expression which have now been mapped at the single-cell level across the neural circuit involved in song production.