The Nuclear Pore Complex (NPC) is the principal gateway between nucleus and cytoplasm that enables exchange of macromolecular cargo. Composed of multiple copies of ~30 different nucleoporins (Nups), the NPC acts as a selective portal, interacting with factors which individually license passage of specific cargo classes. Here we show that two Nups of the inner channel, Nup54 and Nup58, are essential for transposon silencing via the PIWI-interacting RNA (piRNA) pathway in the Drosophila ovary. In ovarian follicle cells, loss of Nup54 and Nup58 results in compromised piRNA biogenesis exclusively from the flamenco locus, whereas knockdowns of other NPC subunits have widespread consequences. This provides evidence that some nucleoporins can acquire specialised roles in tissue-specific contexts. Our findings consolidate the idea that the NPC has functions beyond simply constituting a barrier to nuclear/cytoplasmic exchange, as genomic loci subjected to strong selective pressure can exploit NPC subunits to facilitate their expression.
Sequencing data have been deposited in GEO under accession number GSE152297. Mass Spectrometry data have been deposited to the PRIDE Archive under accessions PXD019670 and PXD019671. Source data files have been provided for Figure 4.
Channel Nuclear Pore Complex subunits are required for transposon silencing in DrosophilaNCBI Gene Expression Omnibus, GSE152297.
Channel Nuclear Pore Complex subunits are required for transposon silencing in DrosophilaPRIDE Archive, PXD019671.
Channel Nuclear Pore Complex subunits are required for transposon silencing in DrosophilaPRIDE Archive, PXD019670.
- Gregory J Hannon
- Gregory J Hannon
- Gregory J Hannon
- Marzia Munafò
- Matthias Soller
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Karsten Weis, ETH Zurich, Switzerland
© 2021, Munafò 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.
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