RT Journal Article
SR Electronic
T1 Daedalus and Gasz recruit Armitage to mitochondria, bringing piRNA precursors to the biogenesis machinery
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 608018
DO 10.1101/608018
A1 Marzia Munafò
A1 Vera Manelli
A1 Federica A. Falconio
A1 Ashley Sawle
A1 Emma Kneuss
A1 Evelyn L. Eastwood
A1 Jun Wen Eugene Seah
A1 Benjamin Czech
A1 Gregory J. Hannon
YR 2019
UL http://biorxiv.org/content/early/2019/04/13/608018.abstract
AB The piRNA pathway is a small RNA-based immune system that silences mobile genetic elements in animal germlines. piRNA biogenesis requires a specialised machinery that converts long single-stranded precursors into small RNAs of ~25-nucleotides in length. This process involves factors that operate in two different subcellular compartments: the nuage/Yb-body and mitochondria. How these two sites communicate to achieve accurate substrate selection and efficient processing remains unclear. Here, we investigate a previously uncharacterized piRNA biogenesis factor, Daedalus (Daed), that is located on the outer mitochondrial membrane. Daed is essential for Zucchini-mediated piRNA production and for the correct localisation of the indispensable piRNA biogenesis factor, Armitage (Armi). We find that Gasz and Daed interact with each other and likely provide a mitochondrial “anchoring platform” to ensure that Armi is held in place, proximal to Zucchini, during piRNA processing. Our data suggest that Armi initially identifies piRNA precursors in nuage/Yb-bodies in a manner that depends upon Piwi and then moves to mitochondria to present precursors to the mitochondrial biogenesis machinery. These results represent a significant step in understanding a critical aspect of transposon silencing, namely how RNAs are chosen to instruct the piRNA machinery in the nature of its silencing targets.