piRNA-like small RNAs target transposable elements in a Clade IV parasitic nematode

Mona Suleiman, Asuka Kounosu, Ben Murcott, Mehmet Dayi, Rebecca Pawluk, Akemi Yoshida, Mark Viney, Taisei Kikuchi, Vicky L Hunt

Research output: Contribution to journalArticlepeer-review

4 Citations (SciVal)


The small RNA (sRNA) pathways identified in the model organism Caenorhabditis elegans are not widely conserved across nematodes. For example, the PIWI pathway and PIWI-interacting RNAs (piRNAs) are involved in regulating and silencing transposable elements (TE) in most animals but have been lost in nematodes outside of the C. elegans group (Clade V), and little is known about how nematodes regulate TEs in the absence of the PIWI pathway. Here, we investigated the role of sRNAs in the Clade IV parasitic nematode Strongyloides ratti by comparing two genetically identical adult stages (the parasitic female and free-living female). We identified putative small-interfering RNAs, microRNAs and tRNA-derived sRNA fragments that are differentially expressed between the two adult stages. Two classes of sRNAs were predicted to regulate TE activity including (i) a parasite-associated class of 21-22 nt long sRNAs with a 5' uridine (21-22Us) and a 5' monophosphate, and (ii) 27 nt long sRNAs with a 5' guanine/adenine (27GAs) and a 5' modification. The 21-22Us show striking resemblance to the 21U PIWI-interacting RNAs found in C. elegans, including an AT rich upstream sequence, overlapping loci and physical clustering in the genome. Overall, we have shown that an alternative class of sRNAs compensate for the loss of piRNAs and regulate TE activity in nematodes outside of Clade V.

Original languageEnglish
Article number10156
JournalScientific Reports
Issue number1
Early online date16 Jun 2022
Publication statusPublished - 31 Dec 2022

Bibliographical note

Funding Information:
VLH was funded by an Elizabeth Blackwell Institute fellowship, a Japanese Society for the Promotion of Science Fellowship (PE16024) and a Wellcome Trust Sir Henry Dale Fellowship (211227/Z/18/Z). For the purpose of Open Access, the author has applied a CC BY public copyright licence to any Author Accepted Manuscript version arising from this submission. MS was funded by a URSA University of Bath PhD studentship. TK was funded by Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Numbers 19H03212 and 17KT0013, and JST CREST Grant Number JPMJCR18S7.

ASJC Scopus subject areas

  • General


Dive into the research topics of 'piRNA-like small RNAs target transposable elements in a Clade IV parasitic nematode'. Together they form a unique fingerprint.

Cite this