Vertical transmission inCaenorhabditisnematodes of RNA molecules encoding a viral RNA-dependent RNA polymerase

• DOI: 10.1073/pnas.1903903116
• Publication Date: 2019-11-19T01:25:18Z
• Authors: Aurélien Richaud; Lise Frézal; Stephen Tahan; Hongbing Jiang; Joshua A. Blatter; Guoyan Zhao; Taniya Kaur; David Wang; Marie-Anne Félix
• Keywords: RNA Silencing

Here, we report on the discovery in Caenorhabditis nematodes of multiple vertically transmitted RNAs coding for putative RNA-dependent RNA polymerases. Their sequences share similarity to distinct viruses, including bunyaviruses, narnaviruses, and sobemoviruses. The are present exclusively as not found DNA form. persist progeny after bleach treatment adult animals, indicating vertical transmission RNAs. We tested one infected strains an uninfected strain that mating animals with resulted progeny. By situ hybridization, detected several these cytoplasm male female germline nematode host. hosts were defective degrading exogenous double-stranded RNAs, which may explain retention viral-like Strikingly, strain, QG551, harbored three virus-like elements. Specific patterns small complementary different observed, suggesting differentially recognized by interference (RNAi) machinery. While viruses family Narnaviridae, known capsidless has been described fungi, observations provide evidence multicellular animal cells harbor similar viruses.