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bioRxiv · 10.1101/2020.05.20.105924

Endogenous viral element-derived piRNAs are not required for production of ping-pong-dependent piRNAs from Diaphorina citri densovirus

Nigg, J. C.·Kuo, Y.-W.·Falk, B. W.
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Abstract

Partial integrations of DNA and non-retroviral RNA virus genomes, termed endogenous viral elements (EVEs), are abundant in arthropod genomes and often produce PIWI-interacting RNAs (piRNAs) speculated to target cognate viruses through the ping-pong cycle, a post-transcriptional RNA silencing mechanism. Here we describe a Diaphorina citri densovirus (DcDV)-derived EVE in the genome of Diaphorina citri. We found that this EVE gives rise to DcDV-specific primary piRNAs and is unevenly distributed among D. citri populations. Unexpectedly, we found that DcDV is targeted by ping-pong-dependent viral piRNAs (vpiRNAs) in D. citri lacking the DcDV-derived EVE, while four naturally infecting RNA viruses of D. citri are not targeted by vpiRNAs. Furthermore, a recombinant Cricket paralysis virus containing a portion of the DcDV genome corresponding to the DcDV-derived EVE was not targeted by vpiRNAs during infection in D. citri harboring the EVE. These results represent the first report of ping-pong-dependent vpiRNAs outside of mosquitoes.

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Nigg, J. C., Kuo, Y.-W., Falk, B. W.. 2020-05-20. Endogenous viral element-derived piRNAs are not required for production of ping-pong-dependent piRNAs from Diaphorina citri densovirus. https://doi.org/10.1101/2020.05.20.105924

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